Am J Med, 2001 Dec 17, 111 Suppl 9A, 19S - 24S Epidemiology of sinusitis in the primary care setting: results from the 1999-2000 respiratory surveillance program; Sokol W; The Respiratory Surveillance Program (RESP) was undertaken over a 10-month period (July to April) during the 1999-2000 respiratory infection season . A total of 16,213 nasal swab samples were taken by primary care physicians in outpatient settings from patients diagnosed as having acute bacterial rhinosinusitis . The samples were sent to a central laboratory where a pathogen was identified and antibiotic susceptibilities were determined . A pathogen could be isolated from 34% of the samples submitted . Four pathogens accounted for 79.7% of all identifiable isolates: Streptococcus pneumoniae (11.3%), Haemophilus influenzae (21.7%), Moraxella catarrhalis (28.9%), and Staphylococcus aureus (17.9%) . Resistance to penicillin was found for S pneumoniae (16% fully resistant, 20% intermediate resistance) . S pneumoniae had a 32% to 35% rate of resistance to erythromycin, azithromycin, and clarithromycin . H influenzae showed a high rate of resistance to clarithromycin (36%) . M catarrhalis had a 15% rate of resistance to erythromycin and a 91.5% rate of resistance to penicillin . Low levels of resistance were seen to the newer fluoroquinolones levofloxacin (minimum inhibitory concentration {MIC}(90) = 2 microg/mL) and gatifloxacin (MIC(90) = 0.5 microg/mL), with the 4 major bacterial isolates having a 95% to 100% rate of susceptibility to these medications . The results from the RESP study can give practicing physicians vital information about pathogen profiles and susceptibilities within their communities and help them in making appropriate treatment choices for their patients with acute rhinosinusitis . Patients with previous antibiotic exposure had a higher incidence of nonsusceptible strains than patients who did not receive prior therapy. Am J Med, 2001 Dec 17, 111 Suppl 9A, 4S - 12S; discussion 36S-38S Frequency of pathogen occurrence and antimicrobial susceptibility among community-acquired respiratory tract infections in the respiratory surveillance program study: microbiology from the medical office practice environment; Pfaller MA et al.; Continuing problems of antimicrobial resistance have prompted the initiation of several surveillance programs . Few, if any, of these programs focus on community-acquired respiratory tract infections seen in routine office-based practices . The Respiratory Surveillance Program (RESP; 1999-2000) in 674 community-based physician office practices in the United States determined the frequency of potential bacterial pathogens including Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis in patients diagnosed clinically with community-acquired pneumonia, acute exacerbations of chronic bronchitis, and sinusitis throughout all 9 US census/geographic regions . Susceptibility to the penicillins (ampicillin, penicillin), oral cephalosporins, fluoroquinolones (gatifloxacin, levofloxacin, ciprofloxacin), macrolides (erythromycin, azithromycin, clarithromycin), tetracycline, and trimethoprim/sulfamethoxazole was determined by reference methods . Patients were required to have a culturable focus of infection, and specimens were immediately sent to a reference laboratory . Among 22,689 total specimens (610 community-acquired pneumonia, 4,779 acute exacerbation of chronic bronchitis, 16,213 sinusitis, 1,087 other), H influenzae was the most commonly isolated organism from patients with community-acquired pneumonia (38%) and acute exacerbation of chronic bronchitis (35%) in all nine geographic regions . S pneumoniae was isolated in 18% of community-acquired pneumonia cases, 13% of acute exacerbation of chronic bronchitis cases, and 11% of sinusitis cases . M catarrhalis was most commonly isolated from the nasopharynx of patients with sinusitis (29%) . High-level resistance to penicillin (2 microg/mL or greater; 16% overall) and the macrolides (32% to 35%) among S pneumoniae varied both with site of infection and with geographic region . The greatest resistance was observed among isolates from the nasopharynx of patients with sinusitis and from patients from the East South Central or South Atlantic regions of the United States . Although the susceptibility of H influenzae and M catarrhalis to the tested antimicrobials did not vary with the type of infection, beta-lactamase-mediated resistance to ampicillin among H influenzae ranged from 15% in New England to 32% in the East South Central region . The fluoroquinolones were highly active against these cultured isolates from community-acquired respiratory tract infection patients, with >99% of all S pneumoniae, H influenzae, and M catarrhalis strains susceptible to gatifloxacin (MIC(90), 0.5 microg/mL) and levofloxacin (MIC(90), 2 microg/mL) . The extended-spectrum fluoroquinolones appear well suited for community-acquired respiratory tract infection therapy, including pathogens other than pneumococcus, H influenzae, and M catarrhalis. J Antimicrob Chemother, 2002 Jan, 49(1), 141 - 7 The treatment of Haemophilus influenzae acute otitis media with amoxicillin protects against reinfection but not against structural changes; Westman E et al.; Acute otitis media (AOM) is the most common reason for outpatient antimicrobial therapy today . With increasing problems with antibiotic resistance, a more restrictive use of antibiotics has been advocated for both single and recurrent episodes . The arguments advanced have been immunological as well as ecological . To study the effects of a 5 day course of amoxicillin on recurrent AOM caused by non-typeable Haemophilus influenzae, Sprague-Dawley rats were used . Amoxicillin was introduced at the clinical peak of the first infection . One month later the animals were rechallenged . Local and systemic changes were monitored by otomicroscopy, bacterial cultures, and analyses of systemic IgG responses and histological changes . Antibiotic treatment accelerated the resolution of the primary infection . After resolution, only minor morphological changes were observed . The protective rate at rechallenge was 100% in the treatment group, compared with 80% in the untreated control group . Although the production of serum IgG antibodies was initially slightly impeded by the treatment, it was significantly higher in treated animals after rechallenge . Major structural changes could not be avoided at the second infection, however, and a significantly higher frequency of myringosclerosis was observed in treated animals . These experimental findings constitute support for further studies of antimicrobial drugs and recurrent AOM. Bioinformatics, 2001 Dec, 17(12), 1105 - 12 Tricross : using dot-plots in sequence-id space to detect uncataloged intergenic features; Ray WC et al.; MOTIVATION: The process of determining the functional sequence content of an organism is confounded by several factors . Large protein coding sequences are relatively easy to find by statistical methods . Smaller proteins however may escape detection due to their size falling below some arbitrary researcher-defined minimum cutoff, or the inability to precisely define a promoter, or translational start (Delcher et al., Nucleic Acids Res., 27, 4636-4641, 1999) . Promoter and regulatory sequences themselves are difficult to define due to a significant amount of allowable sequence variation, as well as a probable lack of any completely accurate whole-organismal gene catalogs to date . Finally, certain genes coding functional RNAs may have insufficient structural or sequence constraints to be detectable by normal sequence structure/pattern searching methods (Eddy and Rivas, Bioinformatics, 16, 583-605, 2000) . In those cases where there are multiple closely related organisms that have been sequenced, there is additional information that may be used in the investigation of sequence content-that being the possible conserved nature of functional sequences between the organisms . We present a method for the utilization of this conserved information to detect genes and other potentially functional sequences that may be missed by standard ORF-calling, RNA finding, and pattern matching software . The tricross programs produce a multi-way cross comparison of three sets of sequences, determine which are conserved in all three sets, and produce a graphical (Virtual Reality Modelling Language-VRML; (ISO/IEC 14772-1: 1997, VDC), 1997) representation as well as alignments of all sequence triples found . The software can also be applied to a pair of sequence sets, though the noise in the results increases . RESULTS: Tricross has been used to examine the intergenic-sequence content of the three archaeal Pyrococcus genomes to determine the most highly related sequences remaining between the annotated protein and RNA coding sequences . Set to relatively stringent similarity requirements for the search, tricross found 101 intergenic sequences conserved among the three organisms . Interestingly, 29 of these appear to contain members of a family of small RNA molecules (Kiss-Laszlo et al., EMBO J., 17, 797-807, 1998) only recently discovered in the Archaea (Armbruster, OSU, Diss., 1988; Omer et al., Science, 288, 517-522, 2000; Gaspin et al., J . Mol . Biol., 297, 895-906, 2000) . While some of the remaining 72 appear to be individual highly conserved promoter sequences, others have no currently known biological significance . Although originally developed to facilitate the examination of intergenic sequences, none of the tricross logic is inherently specific to intergenic sequences . The software can also be applied to gene sequences, and has been used to produce inter-genomic gene order dot-plots for Haemophilus influenzae (Fleischmann et al., Science, 269, 496-512, 1995) versus H.ducreyi (unpublished data), and Neisseria meningiditis Z2491 (serogroup A) (Parkhill et al., Nature, 404, 502-506, 2000) versus Neisseria meningiditis Z58 (serogroup B) (Tettelin et al., Science, 287, 1809-1815, 2000) versus Neisseria gonorrhoeae (Lewis et al., 2000) . AVAILABILITY: The tricross software package is available from CONTACT: ray@biosci.ohio-state.edu; daniels.7@osu.edu; munsonr@pediatrics.ohio-state.edu Supplementary information: Additional data from the cross-genomic comparisons examined in the discussion section are linked from http://www.biosci.ohio-state.edu/~ray/bioinformatics/tricross.html. FEMS Immunol Med Microbiol, 2001 Dec, 32(1), 53 - 64 In vivo expression of Neisseria meningitidis proteins homologous to the Haemophilus influenzae Hap and Hia autotransporters; van Ulsen P et al.; The genome sequences of Neisseria meningitidis serogroup B strain MC58 and serogroup A strain Z2491 were systematically searched for open reading frames (ORFs) encoding autotransporters . Eight ORFs were identified, six of which were present in both genomes, whereas two were specific for MC58 . Among the identified ORFs was the gene encoding the known autotransporter IgA1 protease . The deduced amino acid sequences of the other identified ORFs were homologous to known autotransporters and found to contain an N-terminal signal sequence and a C-terminal domain that could constitute a beta-barrel in the outer membrane . The ORFs NMB1985 and NMB0992, encoding homologs of the Hap (for Haemophilus adhesion and penetration protein) and Hia (for Haemophilus influenzae adherence protein) autotransporters of H . influenzae, were cloned from serogroup B strain H44/76 and expressed in Escherichia coli . Western blots revealed that all sera of patients (n=14) and healthy carriers (n=3) tested contained antibodies against at least one of the recombinant proteins . These results indicate that both genes are widely distributed among N . meningitidis isolates and expressed during colonization and infection. Gene, 2001 Dec 27, 281(1-2), 95 - 102 Design and construction of a Haemophilus influenzae conjugal expression system; Daines DA et al.; Haemophilus influenzae is a fastidious Gram-negative coccobacilli that is a common commensal in the human upper respiratory tract . However, certain strains of this bacterium, including those considered to be nontypeable (NTHi), can cause human diseases ranging from otitis media to meningitis . Although naturally competent, NTHi take up plasmids by transformation very inefficiently, if at all . Many clinical isolates have also proven refractory to the introduction of currently available shuttle vectors via electroporation . Further, it has been difficult to determine protein expression from these vectors, unless specific antisera has been raised or a phenotype conferred . To address these problems, we have designed and constructed a set of broad host range vectors that are transferable via intergeneric conjugation with an Escherichia coli strain carrying chromosomally-encoded transfer functions . These vectors provide a site for cloning promoter::MCS regions and carry genes encoding resistance to one of two different antibiotics . This conjugal system allows the expression of marker genes in NTHi strains, enabling researchers to track the microbe's progress either in vivo using the infant rat model of infection, or in vitro through invasions of human tissue culture cell lines. Arch Pediatr Adolesc Med, 2001 Dec, 155(12), 1301 - 6 Predictors of bacterial meningitis in the era after Haemophilus influenzae; Freedman SB et al.; OBJECTIVE: To determine if, in the era after Haemophilus influenzae type b, the cerebrospinal fluid (CSF) white blood cell (WBC) count can be safely used to stratify children suspected of having bacterial meningitis into low- and high-risk groups . DESIGN: Retrospective analysis of CSF samples . SETTING: Tertiary care pediatric center in Toronto, Ontario, between January 1, 1992, and October 1, 1996 . PATIENTS: All CSF samples collected on children aged 2 months to 17 years were included . The final database consisted of 1617 atraumatic samples from children without prior neurologic or immunologic disease who underwent a lumbar puncture to assess the possibility of community-acquired bacterial meningitis . MAIN OUTCOME MEASURES: The predictive values of CSF WBC count, differential, protein, and glucose . RESULTS: There were 44 cases of bacterial meningitis . Five had 3 CSF WBCs per microliter or less, and 6 had 4 to 30 CSF WBCs per microliter . The negative predictive value of CSF specimens with 30 WBCs per microliter or less for bacterial meningitis was 99.3% . Cerebrospinal fluid samples with greater than 30 WBCs per microliter had a likelihood ratio for bacterial meningitis of 10.3 (95% confidence interval, 8.0-13.1) and a positive predictive value of 22.3% . Other significant predictors of bacterial meningitis included age, CSF glucose, protein, gram stain, CSF-serum glucose ratio, and peripheral blood band count . CONCLUSIONS: Given the occurrence of bacterial meningitis in children in the absence of CSF pleocytosis, other factors should be considered when managing children with suspected bacterial meningitis . Children older than 6 months with 30 CSF WBCs per microliter or less are at low risk for bacterial meningitis . If clinically stable and without other laboratory markers of bacterial meningitis, hospital admission and empiric antibiotic therapy may be unwarranted. Clin Infect Dis, 2001 Dec 15, 33 Suppl 4, S334 - 9 Perspectives on the manufacture of combination vaccines; Vose JR; Evolving regulatory requirements in the United States and Europe create major challenges for manufacturers tasked with production of vaccines that contain > or =9 separate antigens capable of protecting against infectious diseases, such as diphtheria, tetanus, pertussis, polio, hepatitis B, and Haemophilus influenza b, in a single shot . This article describes 10 steps that can facilitate the process of licensing these complex vaccines . It also points out problems associated with the use of animal tests for the crucial step of potency testing for batch release caused by the inherent variability of such tests and the difficulties of interpreting their results. Clin Infect Dis, 2001 Dec 15, 33 Suppl 4, S312 - 8 Combination vaccines: defining and addressing current safety concerns; Halsey NA; Combination vaccines have been in use for >50 years . Historical problems with vaccines, including intussusception after rotavirus vaccine, carrier suppression with tetanus toxoid conjugate vaccines, and decreased immunogenicity of some Haemophilus influenzae type b conjugate vaccines when mixed with acellular pertussis-diphtheria-tetanus, have contributed to some misperceptions about current vaccines . There is no evidence that adding additional vaccines through combination products increases the burden on the immune system, which has the capability of responding to many millions of antigens . Combining antigens usually does not increase adverse effects-in fact, it can lead to an overall reduction in adverse events . Combination products simplify immunization and allow for the introduction of new vaccines without requiring the vaccinee to make additional visits to his or her health care provider . Licensed combination vaccines undergo extensive testing before approval by the United States Food and Drug Administration to assure that the new products are safe and effective. Clin Infect Dis, 2001 Dec 15, 33 Suppl 4, S299 - 305 Evaluating the immune response to combination vaccines; Ball LK et al.; Assessment of the immune responses to combination vaccines in the United States has generally been based on randomized, controlled comparative trials, with such studies designed to rule out predefined differences . In designing clinical studies of the immune response to combination products, attention should be directed toward selecting the appropriate immunologic end points and control groups . Acceptable differences in immune responses between combination and control groups should be predefined, and an adequate statistical plan should be developed . In many cases, it may be necessary to evaluate simultaneous administration of other recommended vaccines, assess schedule changes for 1 or more components of a combination, and bridge immunologic data obtained from international studies to the population of the United States . We discuss the use of immunogenicity studies to support the licensure of combination vaccines when field efficacy studies are either not possible or not required and highlight some recent experiences with combination vaccines containing Haemophilus influenzae type b polysaccharide conjugates. Biochemistry, 2001 Dec 25, 40(51), 15631 - 7 Crystallographic and biochemical analyses of the metal-free Haemophilus influenzae Fe3+-binding protein; Bruns CM et al.; The crystal structure of the iron-free (apo) form of the Haemophilus influenzae Fe(3+)-binding protein (hFbp) has been determined to 1.75 A resolution . Information from this structure complements that derived from the holo structure with respect to the delineation of the process of iron binding and release . A 21 degrees rotation separates the two structural domains when the apo form is compared with the holo conformer, indicating that upon release of iron, the protein undergoes a change in conformation by bending about the central beta-sheet hinge . A surprising finding in the apo-hFbp structure was that the ternary binding site anion, observed in the crystals as phosphate, remained bound . In solution, apo-hFbp bound phosphate with an affinity K(d) of 2.3 x 10(-3) M . The presence of this ternary binding site anion appears to arrange the C-terminal iron-binding residues conducive to complementary binding to Fe(3+), while residues in the N-terminal binding domain must undergo induced fit to accommodate the Fe(3+) ligand . These observations suggest a binding process, the first step of which is the binding of a synergistic anion such as phosphate to the C-terminal domain . Next, iron binds to the preordered half-site on the C-terminal domain . Finally, the presence of iron organizes the N-terminal half-site and closes the interdomain hinge . The use of the synergistic anion and this iron binding process results in an extremely high affinity of the Fe(3+)-binding proteins for Fe(3+) (nFbp K'(eff) = 2.4 x 10(18) M(-1)) . This high-affinity ligand binding process is unique among the family of bacterial periplasmic binding proteins and has interesting implications in the mechanism of iron removal from the Fe(3+)-binding proteins during FbpABC-mediated iron transport across the cytoplasmic membrane. Proteins, 2001 Dec 1, 45(4), 397 - 407 Crystal structure of YecO from Haemophilus influenzae (HI0319) reveals a methyltransferase fold and a bound S-adenosylhomocysteine; Lim K et al.; The crystal structure of YecO from Haemophilus influenzae (HI0319), a protein annotated in the sequence databases as hypothetical, and that has not been assigned a function, has been determined at 2.2-A resolution . The structure reveals a fold typical of S-adenosyl-L-methionine-dependent (AdoMet) methyltransferase enzymes . Moreover, a processed cofactor, S-adenosyl-L-homocysteine (AdoHcy), is bound to the enzyme, further confirming the biochemical function of HI0319 and its sequence family members . An active site arginine, shielded from bulk solvent, interacts with an anion, possibly a chloride ion, which in turn interacts with the sulfur atom of AdoHcy . The AdoHcy and nearby protein residues delineate a small solvent-excluded substrate binding cavity of 162 A(3) in volume . The environment surrounding the cavity indicates that the substrate molecule contains a hydrophobic moiety and an anionic group . Many of the residues that define the cavity are invariant in the HI0319 sequence family but are not conserved in other methyltransferases . Therefore, the substrate specificity of YecO enzymes is unique and differs from the substrate specificity of all other methyltransferases sequenced to date . Examination of the Enzyme Commission list of methyltransferases prompted a manual inspection of 10 possible substrates using computer graphics and suggested that the ortho-substituted benzoic acids fit best in the active site . Eur J Immunol, 2001 Dec, 31(12), 3816 - 24 Rationally designed strings of promiscuous CD4(+) T cell epitopes provide help to Haemophilus influenzae type b oligosaccharide: a model for new conjugate vaccines; Falugi F et al.; The age-related and T cell-independent immunological properties of most capsular polysaccharides limit their use as vaccines, especially in children under 2 years of age . To overcome these limitations, polysaccharide antigens have been successfully conjugated to a variety of carrier proteins, such as diphtheria toxoid or tetanus toxoid (TT) and the diphtheria mutant (CRM197) to produce very successful glycoconjugate vaccines . The increasing demand for new conjugate vaccines requires the availability of additional carriers providing high and long-lasting T helper cell immunity . Here we describe the design and construction of three recombinant carrier proteins (N6, N10, N19) constituted by strings of 6, 10 or 19 human CD4(+) T cell epitopes from various pathogen-derived antigens, including TT and proteins from Plasmodium falciparum, influenza virus and hepatitis B virus . Each of these epitopes is defined as universal in that it binds to many human MHC class II molecules . When conjugated to Haemophilus influenzae type b (Hib) oligosaccharide, these carriers elicit a potent anti-Hib antibody response in mice . In the case of the N19-Hib conjugate, this response is at least as good as that observed with CRM197-Hib, a conjugate vaccine currently used for mass immunization . We also show that some of the universal epitopes constituting the recombinant carriers are specifically recognized by two human in vitro systems, suggesting that T cell memory is provided by the selected epitopes . The data indicate that rationally designed recombinant polyepitope proteins represent excellent candidates for the development and clinical testing of new conjugate vaccines. Glycobiology, 2001 Nov, 11(11), 957 - 67 Genetic basis for expression of the major globotetraose-containing lipopolysaccharide from H . influenzae strain Rd (RM118); Hood DW et al.; A genetic basis for the biosynthetic assembly of the globotetraose containing lipopolysaccharide (LPS) of Haemophilus influenzae strain RM118 (Rd) was determined by structural analysis of LPS derived from mutant strains . We have previously shown that the parent strain RM118 elaborates a population of LPS molecules made up of a series of related glycoforms differing in the degree of oligosaccharide chain extension from the distal heptose residue of a conserved phosphorylated inner-core element, L-alpha-D-Hepp-(1-->2)-L-alpha-D-Hepp-(1-->3)-{beta-D-Glcp-(1-->4)-}-L-alpha-D-Hepp-(1-->5)-alpha-Kdo . The fully extended LPS glycoform expresses the globotetraose structure, beta-D-GalpNAc-(1-->3)-alpha-D-Galp-(1-->4)-beta-D-Galp-(1-->4)-beta-D-Glcp . A fingerprinting strategy was employed to establish the structure of LPS from strains mutated in putative glycosyltransferase genes compared to the parent strain . This involved glycose and linkage analysis on intact LPS samples and analysis of O-deacylated LPS samples by electrospray ionization mass spectrometry and 1D (1)H-nuclear magnetic resonance spectroscopy . Four genes, lpsA, lic2A, lgtC, and lgtD, were required for sequential addition of the glycoses to the terminal inner-core heptose to give the globotetraose structure . lgtC and lgtD were shown to encode glycosyltransferases by enzymatic assays with synthetic acceptor molecules . This is the first genetic blueprint determined for H . influenzae LPS oligosaccharide biosynthesis, identifying genes involved in the addition of each glycose residue. Otolaryngol Head Neck Surg, 2001 Dec, 125(6), 593 - 7 Molecular typing of paired bacterial isolates from the adenoid and lateral wall of the nose in children undergoing adenoidectomy: implications in acute rhinosinusitis; Bernstein JM et al.; OBJECTIVE: Recent studies have suggested that the origin of bacteria that enter the lateral wall of the nose and paranasal sinuses arise from the nasopharynx . The purpose of this study was to compare the molecular biological profiles of potential pathogens found in the nasopharynx and lateral wall of the nose concomittantly in children undergoing surgery for upper respiratory tract disease . STUDY DESIGN AND SETTING: Fifty-two children undergoing adenoidectomy for either tonsillectomy or adenoidectomy (hypertrophy) or otitis media with effusion were studied . Bacterial cultures were taken from the crypts of the adenoids and from the lateral wall of the nose under endoscopic control after sterilization of the vestibule and inferior turbinate . Routine cultures of these areas were performed in the bacteriology laboratory of the Children's Hospital of Buffalo . RESULTS: Bacterial pathogens were isolated from 79% of adenoids and 46% of lateral walls of the nose . Molecular typing of pairs of nontypable Haemophilus influenzae, Streptococcus pneumoniae, and Moraxella catarrhalis revealed that in 16 of 18 pairs (89%) the identical strain was present in both sites simultaneously . CONCLUSIONS: These results support the concept that when potential bacterial pathogens that may cause acute bacterial rhinosinusitis are found concomitantly in the nasopharynx and lateral wall of the nose, they are usually identical. FEMS Microbiol Rev, 2001 Dec, 25(5), 531 - 52 Bacterial plasminogen activators and receptors; Lahteenmaki K et al.; Invasive bacterial pathogens intervene at various stages and by various mechanisms with the mammalian plasminogen/plasmin system . A vast number of pathogens express plasmin(ogen) receptors that immobilize plasmin(ogen) on the bacterial surface, an event that enhances activation of plasminogen by mammalian plasminogen activators . Bacteria also influence secretion of plasminogen activators and their inhibitors from mammalian cells . The prokaryotic plasminogen activators streptokinase and staphylokinase form a complex with plasmin(ogen) and thus enhance plasminogen activation . The Pla surface protease of Yersinia pestis resembles mammalian activators in function and converts plasminogen to plasmin by limited proteolysis . In essence, plasminogen receptors and activators turn bacteria into proteolytic organisms using a host-derived system . In Gram-negative bacteria, the filamentous surface appendages fimbriae and flagella form a major group of plasminogen receptors . In Gram-positive bacteria, surface-bound enzyme molecules as well as M-protein-related structures have been identified as plasminogen receptors, the former receptor type also occurs on mammalian cells . Plasmin is a broad-spectrum serine protease that degrades fibrin and noncollagenous proteins of extracellular matrices and activates latent procollagenases . Consequently, plasmin generated on or activated by Haemophilus influenzae, Salmonella typhimurium, Streptococcus pneumoniae, Y . pestis, and Borrelia burgdorferi has been shown to degrade mammalian extracellular matrices . In a few instances plasminogen activation has been shown to enhance bacterial metastasis in vitro through reconstituted basement membrane or epithelial cell monolayers . In vivo evidence for a role of plasminogen activation in pathogenesis is limited to Y . pestis, Borrelia, and group A streptococci . Bacterial proteases may also directly activate latent procollagenases or inactivate protease inhibitors of human plasma, and thus contribute to tissue damage and bacterial spread across tissue barriers. HIV Clin Trials, 2001 Nov-Dec, 2(6), 453 - 9 Presence of macrolide resistance in respiratory flora of HIV-Infected patients receiving either clarithromycin or azithromycin for Mycobacterium avium complex prophylaxis; Aberg JA et al.; Clarithromycin 500 mg po bid or azithromycin 1200 mg po weekly is recommended as first line prophylaxis for Mycobacterium avium complex (MAC) in patients with HIV infection whose CD4 counts are <50 cells/microL . HIV-infected patients with CD4+ T-cell counts <200 cells/microL were randomized to receive either clarithromycin 500 mg po bid or azithromycin 1200 mg po weekly for 12 weeks . Nasopharyngeal swabs for Streptococcus pneumoniae and Haemophilus influenzae plus an anterior nare culture for Staphylococcus aureus were obtained at pretreatment, at 6 weeks, and at 12 weeks . A throat culture for oral flora was obtained for susceptibility testing against erythromycin . Minimum inhibitory concentrations (MICs) for clarithromycin and azithromycin were performed on all S . pneumoniae, H . influenzae, and S . aureus isolates . The study was terminated after respiratory flora, from all participants, revealed macrolide resistance . Because results of recent randomized trials indicate minimal efficacy of continuing MAC prophylaxis in patients who respond to potent combination antiretroviral therapy, the observed high incidence of macrolide-resistant bacterial colonization of the respiratory tract in this trial supports the discontinuation of macrolide prophylaxis in all AIDS patients whose CD4 counts have risen above 100 cells/microL. J Infect Dis, 2001 Dec 15, 184(12), 1617 - 20 Epub 2001 Dec 03. Immune response of premature infants to meningococcal serogroup C and combined diphtheria-tetanus toxoids-acellular pertussis-Haemophilus influenzae type b conjugate vaccines; Slack MH et al.; To determine the immune response of premature infants to meningococcal serogroup C capsular polysaccharide (MCC) and combined diphtheria-tetanus toxoids-acellular pertussis-Haemophilus influenzae type b (DTaP-Hib) conjugate vaccines, 105 infants born at <32 weeks' gestation had Hib IgG geometric mean concentrations (GMCs) and MCC serum bactericidal antibody (SBA) geometric mean titers (GMTs) measured 1 month after the third immunization . Term infants served as control subjects . Premature infants had Hib GMCs of 0.27 microg/mL, with 21% achieving GMCs >1.0 microg/mL, compared with 0.81 microg/mL and 46% in term infants (P<.001 and P=.003, respectively) . The MCC SBA GMT was 398, with 99% achieving an SBA > or =8, compared with 380 and 98% in term infants (P=.84 and P=1.0, respectively) . Hib IgG was associated with age at third immunization (P<.001) . When combined with the DTaP vaccine used in this study, the Hib GMC of premature infants was extremely low . The SBA GMT to MCC was similar to that of term infants. Clin Infect Dis, 2002 Jan 15, 34(2), 191 - 7 Epub 2001 Dec 07. Concentration and avidity of anti-Haemophilus influenzae type b (Hib) antibodies in serum samples obtained from patients for whom Hib vaccination failed; Breukels MA et al.; Haemophilus influenzae type b (Hib) conjugate vaccines are extremely effective in protecting infants and children from invasive Hib infections; however, vaccine failures do occur . The anti-Hib antibody production was studied both quantitatively and qualitatively in 12 patients who experienced Hib failure, all of whom had normal serum immunoglobulin concentrations and all of whom were without clinical risk factors for invasive Hib disease . Both anti-Hib antibody concentration and immunoglobulin-G2 anti-Hib antibody avidity were significantly lower in patients who experienced Hib failure, at onset of disease and after reconvalescence, when compared with controls . This finding suggests that the patients who developed invasive Hib disease--despite having received 3-4 Hib conjugate vaccinations--were inadequately primed by these vaccinations. Ultraschall Med, 2001 Dec, 22(6), 289 - 92 {Functional hyposplenia after allogenic bone marrow transplantation: a case report}; Wollenberg B et al.; Functional hyposplenia/asplenia is a severe longterm complication after allogeneic stemcell transplantation predominantly seen in patients who suffer from extensive chronic graft versus host disease (cGvHD) . The risk of acquiring an overwhelming infection with encapsulated bacteria is ca . four fold increased in patients with functional hyposplenia/asplenia . Therefore follow up of patients who have received allogeneic blood stem cells (bone marrow or peripheral blood stem cells) should embrace screening for functional hyposplenia . When functional hyposplenia is diagnosed triple vaccination against streptococcus pneumonia, Haemophilus influenza type B and Meningococcus neisseria should be considered . Goldstandard in diagnosing functional hyposplenia is hepatosplenic scintigraphy . We present the case of 37 year old female in whom sonography was indicative of functional hyposplenia . The diagnosis was confirmed by scintigraphy . Sonography including color coded duplex sonography is a safe and cost saving procedure . Sensitivity, Specificity and predictive value of the following sonographic finding: a) decreasing splenic size and b) diminished or absent parenchymal blood flow are currently evaluated in a prospective study. Blood, 2001 Dec 15, 98(13), 3505 - 12 Immunity of patients surviving 20 to 30 years after allogeneic or syngeneic bone marrow transplantation; Storek J et al.; The duration of immunodeficiency following marrow transplantation is not known . Questionnaires were used to study the infection rates in 72 patients surviving 20 to 30 years after marrow grafting . Furthermore, in 33 of the 72 patients and in 16 donors (siblings who originally donated the marrow) leukocyte subsets were assessed by flow cytometry . T-cell receptor excision circles (TRECs), markers of T cells generated de novo, were quantitated by real-time polymerase chain reaction . Immunoglobulin G(2) (IgG(2)) and antigen-specific IgG levels were determined by enzyme-linked immunosorbent assay . Infections diagnosed more than {corrected} 15 years after transplantation occurred rarely . The average rate was 0.07 infections per patient-year (one infection every 14 years), excluding respiratory tract infections, gastroenteritis, lip sores, and hepatitis C . The counts of circulating monocytes, natural killer cells, B cells, CD4 T cells, and CD8 T cells in the patients were not lower than in the donors . The counts of TREC(+) CD4 T cells in transplant recipients younger than age 18 years (at the time of transplantation) were not different from the counts in their donors . In contrast, the counts of TREC(+) CD4 T cells were lower in transplant recipients age 18 years or older, even in those with no history of clinical extensive chronic graft-versus-host disease, compared with their donors . The levels of total IgG(2) and specific IgG against Haemophilus influenzae and Streptococcus pneumoniae were similar in patients and donors . Overall, the immunity of patients surviving 20 to 30 years after transplantation is normal or near normal . Patients who received transplants in adulthood have a clinically insignificant deficiency of de novo-generated CD4 T cells, suggesting that in these patients the posttransplantation thymic insufficiency may not be fully reversible. Am J Respir Crit Care Med, 2001 Dec 1, 164(11), 2114 - 9 Nontypeable Haemophilus influenzae in the lower respiratory tract of patients with chronic bronchitis; Bandi V et al.; The frequency of colonization and intracellular localization of nontypeable Haemophilus influenzae (NTHi) in the lower respiratory tract was determined in healthy adults and in clinically stable and acutely ill chronic bronchitis (CB) patients . NTHi was recovered from bronchial wash or bronchial brush specimens in 6 of 23 (26%) stable CB patients and in 1 of 15 (7%) CB patients with a respiratory exacerbation . No NTHi (0 of 26) was recovered from lower tract specimens of healthy adults undergoing anesthesia for elective surgery . Molecular typing of NTHi strains revealed that five of nine patients with stable CB had different strains in upper respiratory tract and bronchial wash/brush specimens collected simultaneously . Four stable patients with CB had different strains recovered on repeat bronchoscopy . These results demonstrate the frequent colonization of the lower airways of stable CB patients with multiple strains of NTHi . Bronchial biopsies also were examined for intracellular NTHi by in situ hybridization and immunofluorescence microscopy . Intracellular NTHi were found in 0 of 7 healthy adults, 8 of 24 patients with clinically stable CB, and 13 of 15 acutely ill CB patients . This observation suggests a role for intracellular infection by NTHi in the pathogenesis of exacerbations of CB. Vaccine, 2001 Dec 12, 20(5-6), 826 - 37 Maternal immunization with pneumococcal polysaccharide vaccine in the third trimester of gestation; Munoz FM et al.; In a randomized, double blinded study, 23-valent pneumococcal polysaccharide vaccine (PSV) or conjugate Haemophilus influenzae type b (HbOC) vaccine was administered to 60 healthy women in the third trimester of gestation . Total IgG, IgG1, and IgG2 antibodies to pneumococcal serotypes 6B, 14, 19F and 23F were measured by ELISA in mothers prior to immunization, at delivery and 7 months after delivery, and in infants at birth (cord blood), 2 and 7 months after delivery . IgA was evaluated in breast milk at 2 and 7 months, and opsonophagocytic activity in cord blood . PSV was safe and immunogenic in pregnant women . Transplacental transmission of vaccine-specific antibodies was efficient . Maternal immunization with PSV resulted in significantly higher concentrations of pneumococcal antibodies in infants at birth and at 2 months of age, and greater functional opsonophagocytic activity of passively acquired IgG antibody. Vaccine, 2001 Dec 12, 20(5-6), 647 - 50 Materno-foetal transfer of H . influenzae and pneumococcal antibodies is influenced by prematurity and low birth weight: implications for conjugate vaccine trials; Okoko BJ et al.; The influence of prematurity and low birth weight (LBW) on transplacental transfer of Haemophilus influenza type B and Streptococcus pneumoniae antibodies was assessed in 213 mothers and their neonates from Gambia . Paired maternal and cord serum samples were tested for specific IgG antibody titres for H . influenza and S . pneumococcus antigens using enzyme linked immunosorbent assay . Prematurity and LBW was significantly associated with reduced placental antibody transfer for these antigens.The reduced materno-foetal transfer of these antibodies in this vulnerable population of babies may further predispose them to more bacterial infections . These findings are of practical importance to the vaccination strategies. Int J Pediatr Otorhinolaryngol, 2002 Jan 11, 62(1), 17 - 23 A nasal spray with alpha-haemolytic streptococci as long term prophylaxis against recurrent otitis media; Tano K et al.; Previous studies have shown that children with recurrent acute otitis media (rAOM) have significantly lower quantities of alpha-haemolytic streptococci (AHS) in the nasopharynx than healthy children . Furthermore children with otitis media have AHS with lower inhibitory activity in vitro on Streptococcus pneumoniae and non-typable Haemophilus influenzae compared with healthy children . A randomised, placebo controlled and double blind clinical study among children with rAOM was designed to determine whether or not a nasal spray, containing AHS with very good inhibitory activity on the three most common OM pathogens, could be an alternative to tympanostomy tube insertion . Forty three children under 4 years of age were included in the study . The children sprayed once daily for 4 months and were monitored for 6 months . Sixteen children in the active group and 20 children in the placebo group were evaluated . The result showed no significant differences regarding the number of episodes of AOM, with seven recurrences in the active group and eight in the placebo group . No significant changes of the nasopharyngeal flora could be detected during the study period regarding the OM pathogens . Nasal spray according to the performed schedule is not yet an alternative to tympanostomy tubes in children with rAOM . The possibility of increasing the efficacy of this ecological treatment, by using pre-treatment antibiotics, more adhesive bacteria and alternative treatment schedules is discussed. Int J Antimicrob Agents, 2001 Dec, 18(6), 497 - 502 Epidemiological aspects of antibiotic resistance in respiratory pathogens; Mlynarczyk G et al.; Respiratory infections are the most frequent reason for primary health care consultation . The main causes of respiratory tract infections in children are viruses and the most common types are upper respiratory tract infections: common cold, pharyngitis, otitis media and sinusitis . Pneumonia is much more serious . As well as viruses, bacteria are often involved in respiratory tract infections . Three bacterial species are most commonly isolated: Streptococcus pneumoniae, non-encapsulated Haemophilus influenzae and Moraxella (Branhamella) catarrhalis . The most common bacterial cause of pharyngitis is Streptococcus pyogenes . Bacteria isolated from community-acquired infection usually are sensitive to the majority of suitable drugs, but during the past two decades, significant antibiotic resistance has emerged . Resistance to penicillins has spread among H . influenzae and S . pneumoniae . The mechanism of penicillin resistance in H . influenzae is mainly by production of beta-lactamases TEM-1 and ROB-1, whereas in S . pneumoniae resistance is an effect of the changes in penicillin binding proteins . Among respiratory pathogens, resistance to tetracyclines, macrolides, trimethoprim-sulphamethoxazole and fluoroquinolones has also appeared . Several mechanisms depending on changes in target, active efflux and modifying enzymes are involved. Structure (Camb), 2001 Dec, 9(12), 1135 - 41 Structure of the universal stress protein of Haemophilus influenzae; Sousa MC et al.; BACKGROUND: The universal stress protein UspA is a small cytoplasmic bacterial protein whose expression is enhanced several-fold when cellular viability is challenged with heat shock, nutrient starvation, stress agents which arrest cell growth, or DNA-damaging agents . UspA enhances the rate of cell survival during prolonged exposure to such conditions, suggesting that it asserts a general "stress endurance" activity . However, neither the structure of UspA nor the biochemical mechanism by which it protects cells from the broad spectrum of stress agents is known . RESULTS: The crystal structure of Haemophilus influenzae UspA reveals an asymmetric dimer with a tertiary alpha/beta fold similar to that of the Methanococcus jannaschi MJ0577 protein, a protein whose crystal structure revealed a novel ATP binding motif . UspA differs significantly from the MJ0577 structure in several details, including the triphosphate binding loop of the ATP binding motif; UspA shows no ATP binding activity . CONCLUSIONS: Within the universal stress protein family that is delineated by sequence similarity, UspA is the only member which has been correlated with a cellular activity, and MJ0577 is the only member which has been assigned a biochemical activity, i.e., ATP binding . UspA has a similar fold to the MJ0577 protein but does not bind ATP . This suggests that members of this protein family will segregate into two groups, based on whether or not they bind ATP . By implication, one subset of the universal stress proteins presumably has an ATP-dependent function, while another subset functions in ATP-independent activities. Clin Microbiol Infect, 2001 Nov, 7(11), 589 - 96 Optimisation of antimicrobial therapy using pharmacokinetic and pharmacodynamic parameters; Jacobs MR; To understand the relationship between drug dose and efficacy, pharmacokinetic (PK) and pharmacodynamic (PD) characteristics need to be integrated . Patterns of antimicrobial activity fall into one of two major patterns: time-dependent killing and concentration-dependent killing . Time-dependent killing is characteristic of many antibiotic classes, such as beta-lactams and macrolides, and seeks to optimise the duration of exposure of a pathogen to an antimicrobial . The major PK/PD parameter correlating with efficacy of time-dependent antimicrobials is the serum concentration present for 40-50% of the dosing interval, and this concentration is the susceptibility limit or breakpoint for the dosing regimen used . The second pattern, concentration-dependent killing, seeks to maximise antimicrobial concentration and is seen with aminoglycosides, quinolones and azalides . The major PK/PD parameter correlating with efficacy of these agents is the 24-h area under the curve to MIC ratio, which should be > or =25 for less severe infections or in immunocompetent hosts, and > or =100 in more severe infections or in immunocompromised hosts . PK/PD breakpoints for concentration-dependent agents can therefore be calculated from the formula AUC divided by 25 . This enables development of PK/PD breakpoints based on the above parameters for time- and concentration-dependent agents for defined dosing regimens . For an antimicrobial to be useful empirically, the MIC90s of the agent against the common pathogens responsible for the disease being treated should be below the PK/PD breakpoint . This is particularly important for oral dosing regimens for treating emerging resistant respiratory tract pathogens, where efficacy against the predominant pathogens, Streptococcus pneumoniae and Haemophilus influenzae, is required. Paediatr Drugs, 2001, 3(11), 793 - 801 Prevention and management of infection in children with sickle cell anaemia; Wong WY; Sickle cell anaemia (SCA) predisposes a child to infections for various reasons, including increased bone marrow turnover, poor perfusion and functional asplenia leading to decreased opsonisation of polysaccharide encapsulated organisms . Bacteria and viruses that most frequently cause serious infections in children with sickle cell disease are Streptococcus pneumoniae, Haemophilus influenzae type b, Salmonella spp., Escherichia coli, Staphylococcus aureus, Mycoplasma pneumoniae, Chlamydia pneumoniae, parvovirus B19 and hepatitis A, B and C viruses . Penicillin prophylaxis has decreased the incidence of infection-related morbidity and mortality significantly in children with SCA . Children <3 years of age are administered oral penicillin 125mg twice daily, and the dose is increased to 250mg twice daily for the >3 to 5 year age group . Adherence to the penicillin prophylactic regimen is recommended for children with SCA who are >5 years of age . For children with SCA who have recurrent invasive pneumococcal infections, an effort is made to keep the child on penicillin prophylaxis indefinitely . The administration of various childhood vaccines has also made an appreciable impact on the overall morbidity and mortality associated with infection in children with SCA . The administration of the heptavalent conjugate pneumococcal vaccine (PCV7) has provided control of invasive pneumococcal infections, and the prophylactic use of the H . influenzae type b conjugate vaccine has reduced the incidence of septicaemia and meningitis caused by this organism . Other vaccines used prophylactically in children with SCA include hepatitis A and B, and vaccines against influenza and varicella viruses . The immediate administration of intravenous antibacterials, after appropriate blood and urine cultures, is of great importance in the treatment of the febrile child with SCA . Ceftriaxone and cefotaxime have been recommended for the treatment of septic episodes in SCA associated with S . pneumoniae, Haemophilus and Salmonella spp . Infection with Yersinia enterocolitica may be treated with cefotaxime or an aminoglycoside . The prevalence of Helicobacter pylori infection in SCA is unknown . Effective therapies include metronidazole, tetracycline or amoxicillin . Parvovirus infections require supportive care and specific antiviral therapy is not indicated . The judicious use of antimicrobials is encouraged in view of the worldwide emergence of multidrug-resistant strains . The long term sequelae associated with infections in children with SCA can be decreased with the implementation of immunisation programmes and effective and prompt treatment with appropriate antibacterials. CNS Drugs, 2001, 15(12), 909 - 19 Bacterial meningitis: current controversies in approaches to treatment; Williams AJ et al.; Acute bacterial meningitis continues to be a disease with unacceptably high mortality and morbidity rates in both adults and children worldwide, despite advances in antibacterial therapy . Death or permanent disability occurs frequently . The causative organism varies with age, immune function and immunisation status . Infection with Neisseria meningitidis, Streptococcus pneumoniae and Haemophilus influenzae type b (Hib) is associated with the majority of cases, with Listeria monocytogenes and Streptococcus agalactiae being more prevalent pathogens at the extremes of age (<3 months or >50 years) . Antibacterial resistance is an increasing problem, particularly in pneumococcal bacteria but increasingly in other organisms . The increasing prevalence of resistance of pneumococcus to penicillin and the cephalosporins complicates therapy and may have an important impact on treatment outcome . Increased understanding of the pathophysiology has allowed advances in diagnosis and therapy . The use of adjunctive corticosteroids remains controversial, but is probably beneficial in reducing neurological sequelae in children . In adults the evidence is less clear . Vaccination has virtually eradicated Hib meningitis in some countries . Recent introduction of a conjugate vaccine against serogroup C meningococci in the UK has caused a dramatic reduction in the incidence of invasive disease due to this organism . A 7-valent pneumococcal vaccine promises a similar reduction in the incidence of invasive pneumococcal disease . In the meantime, the emergence of widespread resistance of organisms to antibacterial agents, in particular among the common organisms causing bacterial meningitis, remains the biggest challenge in therapy. Pediatr Infect Dis J, 2001 Sep, 20(9), 829 - 37 Bacteriologic and clinical efficacy of high dose amoxicillin/clavulanate in children with acute otitis media; Dagan R et al.; OBJECTIVES: To determine the bacteriologic and clinical efficacy of high dose amoxicillin/clavulanate (90/6.4 mg/kg/day) against common bacterial pathogens causing acute otitis media (AOM), including penicillin-resistant Streptococcus pneumoniae (PRSP) . METHODS: In this open label multicenter study, 521 infants and children with AOM {mean age, 18.6 months; age < 24 months, n = 375 (72%)} were treated with amoxicillin/clavulanate 90/6.4 mg/kg/day in two divided doses for 10 days . Bilateral otitis media, previous episodes of AOM, antibiotic treatment within 3 months and day-care attendance were recorded in 60.1, 35.7, 50.2 and 38.2% of the children, respectively . Tympanocentesis was performed before the first dose and repeated on Days 4 to 6 for all children with S . pneumoniae at 22 centers and for all children with any pathogen at 3 centers . Clinical response was assessed at end of therapy . RESULTS: Pathogens were isolated from 355 (68%) of 521 enrolled children; 180 children underwent repeat tympanocentesis and were bacteriologically evaluable . Baseline pathogens were S . pneumoniae (n = 122 enrolled/93 bacteriologically evaluable), Haemophilus influenzae (n = 160/51), both (n = 37/32) and others (n = 36/4) . Pathogens were eradicated from 172 (96%) of 180 bacteriologically evaluable children . Overall 122 (98%) of 125 isolates of S . pneumoniae were eradicated, including 31 (91%) of 34 PRSP isolates (penicillin MICs 2 to 4 micrograms/ml) . Seventy-eight (94%) of 83 isolates of H . influenzae were eradicated . Symptoms and otoscopic signs of acute inflammation were completely resolved or improved on Days 12 to 15 in 263 (89%) of 295 clinically evaluable children with bacteriologically documented AOM . CONCLUSIONS: On the basis of bacteriologic outcome on Days 4 to 6 and clinical outcome on Days 12 to 15, we found that high dose amoxicillin/clavulanate (90/6.4 mg/kg/day) was highly efficacious in children with AOM, including those most likely to fail treatment, namely children < 24 months of age and those with infectious caused by PRSP. Pediatr Infect Dis J, 2001 Aug, 20(8), 779 - 84 Nasopharyngeal colonization by Haemophilus influenzae in children living in an orphanage; Raymond J et al.; AIM: To study colonization and transmission of Haemophilus influenzae in a cohort of children <2 years old living in the unique epidemiologic conditions of a closed community of an orphanage . METHODS: Fifty-three children, ages 0 to 24 months, were followed for 1 year . All children >2 months were vaccinated against H . influenzae serotype b . Nasopharyngeal cultures were collected monthly or, in children <6 months of age, every 2 weeks . Antibiotic susceptibility, serotype, biotype and genotype (pulsed field gel electrophoresis) of each isolate were determined . As control, 39 H . influenzae isolates were recovered from various regions in France . RESULTS: The mean monthly rate of carriage was 45% ranging from 17 to 70% . Most isolates belonged to biotype II (62%), 4 isolates to serotype f (3.6%) and none to serotype b, and 60% of the 111 isolates produced beta-lactamase . A complete concordance was found among biotype, serotype, pulsotype and antimicrobial susceptibility . On average children were sequentially colonized by 3 different isolates . The mean duration of carriage for a given isolate was approximately 1.4 months . In younger children the mean age of primary colonization was 2 months . Contrasting with the high genetic heterogeneity of 39 control isolates, most isolates (82%) belonged to only 5 pulsotypes . Three main H . influenzae clones rapidly spread in the community and colonized children in waves . CONCLUSION: During early life nasopharyngeal colonization by H . influenzae is a dynamic phenomenon with sequential carriage of various clones spreading in the community. Pediatr Infect Dis J, 2001 Aug, 20(8), 767 - 74 Haemophilus influenzae type b disease: impact and effectiveness of diphtheria-tetanus toxoids-acellular pertussis (-inactivated poliovirus)/H . influenzae type b combination vaccines; Schmitt HJ et al.; BACKGROUND: Since 1996 in Germany primary infant immunization against Haemophilus influenzae has been most commonly given in the form of diphtheria-tetanus toxoids-acellular pertussis/H . influenzae type b (DTaP/Hib) or diphtheria-tetanus toxoids-acellular pertussis (-inactivated poliovirus)/H . influenzae type b (DTaP-IPV/Hib) combination vaccines . These combination vaccines elicit lower anti-Hib antibody concentrations than the equivalent Hib conjugate administered as a separate injection, but the clinical relevance of this phenomenon is unknown . METHODS AND FINDINGS: To assess the impact of DTaP/Hib combination vaccines on the incidence of invasive Hib disease in Germany, two independent surveillance systems, one hospital- and one laboratory-based, were used during 1998 and 1999 for detection of cases . Vaccination histories of all cases detected were obtained by telephone contact with parents or health care providers . During the 2-year study period invasive H . influenzae disease in the <5-year age group continued to fall, with a mean annual incidence of 1.01/100 000 children . National vaccination coverage rates revealed that only 70% of children given DTaP/Hib or DTaP-IPV/Hib received the recommended three doses in their first year of life, but the overall effectiveness of these vaccines was high at 97.5% (95% confidence interval, 96.3 to 98.4) for those who had received at least one dose . In subjects who received the full 3-dose schedule, effectiveness was 98.8% (95% confidence interval, 98.2 to 99.3) . CONCLUSION: Although it is well-documented that DTaP/Hib vaccines elicit lower anti-Hib titers than separate vaccines, such combinations are effective in reducing the incidence of invasive H . influenzae type b disease. Pediatr Infect Dis J, 2001 Nov, 20(11), 1039 - 42 Short term oral cefixime therapy for treatment of bacterial conjunctivitis; Wald ER et al.; BACKGROUND: There have been few controlled studies evaluating treatment of bacterial conjunctivitis beyond the newborn period . Topical therapy of bacterial conjunctivitis achieves a clinical cure but does not prevent acute otitis media (AOM) . OBJECTIVES: The aim of this study was to compare systemic antibiotic therapy (cefixime) with topical therapy with polymyxin-bacitracin for treatment of acute bacterial conjunctivitis with regard to clinical and bacteriologic cure and prevention of AOM . METHODS: This study was a randomized, double blind, placebo-controlled trial of polymyxin-bacitracin ointment and oral placebo vs . topical placebo and oral cefixime in children with presumed acute bacterial conjunctivitis . Topical therapy was administered for 7 days; oral therapy was administered for 3 days . Bacterial cultures were obtained at entry and on Day 3 of treatment . Children were examined on Days 3 and 10 or if they worsened within 15 days of entry . RESULTS: Eighty children were enrolled in the study . Bacterial cultures of the conjunctiva were positive in 70% of children: Haemophilus influenzae (53.7%); Streptococcus pneumoniae (13.8%); H . influenzae and S . pneumoniae (1.2%); and Moraxella catarrhalis (1.3%) . There were 7 (17.5%) bacteriologic failures among children receiving topical antibiotic and oral placebo and 15 (37.5%) bacteriologic failures among children receiving topical placebo and oral cefixime (P = 0.07 with Yates correction) . There was no difference between study groups with regard to either clinical cure or the development of AOM . Nine children (11%), 5 who received active topical therapy and 4 who received active oral drug, developed AOM either during or within 15 days of study entry . CONCLUSION: Cefixime was not more effective than topical polymyxin-bacitracin in either the eradication of conjunctival colonization with respiratory pathogens or the prevention of AOM in children with acute bacterial conjunctivitis. Pediatr Infect Dis J, 2001 Nov, 20(11), 1017 - 21 Microbiology of acute otitis media recently treated with aminopenicillins; Block SL et al.; INTRODUCTION: Sparse recent data are available in the United States regarding the pathogens of acute otitis media (AOM) most likely to be recovered from children recently treated with the two most frequently prescribed antibiotics, amoxicillin or amoxicillin/clavulanate (AMC) . METHODS: Of the 704 rural Kentucky children with culture-positive AOM who underwent a single tympanocentesis or culture of otorrhea between 1992 and 1998, 96 pathogens were recovered from 90 children during therapy or within 7 days posttherapy with an aminopenicillin . Identification and susceptibility testing of AOM pathogens were performed by routine National Committee for Clinical Laboratory Standards methods . RESULTS: Pathogens recovered from children with AOM recently treated (0 to 7 days) with amoxicillin (n = 38) and AMC (n = 58), respectively, were as follows: Haemophilus influenzae (beta-lactamase-negative), 16 and 29%; H . influenzae (beta-lactamase-positive), 11 and 22%; penicillin-susceptible Streptococcus pneumoniae, 26 and 12%; intermediately penicillin-nonsusceptible S . pneumoniae (PNSP), 20 and 10%; resistant PNSP 13 and 17%; Moraxella catarrhalis (beta-lactamase-positive), 13 and 7%; and Streptococcus pyogenes, 3 and 2% . H . influenzae was also isolated from 8 (75%) of 12 children treated with high dose AMC ( approximately 80 mg/kg/day amoxicillin component) . Significantly fewer children recently treated with amoxicillin were otitis-prone than those given AMC (24% vs . 74%, P < 0.0001) . CONCLUSIONS: The predominant pathogen recovered from children with AOM recently treated with amoxicillin was S . pneumoniae (59%) rather than beta-lactamase-producing organisms (24%) . H . influenzae was the predominant (51%) pathogen, rather than PNSP (27%), recovered from children recently treated with AMC. Med Clin (Barc), 2001 Nov 24, 117(17), 657 - 9 {Etiology of community-acquired pneumonia in ambulatory patients . Usefulness of a diagnostic investigation protocol using detection of Streptococcus pneumoniae and Legionella pneumophila antigens in urine samples}; Mirete Ferrer C et al.; BACKGROUND: To determine the etiology of community-acquired pneumonia (CAP) in ambulatory patients and to assess the efficiency of a diagnostic protocol by using tests to detect bacterial antigens in urine samples . PATIENTS AND METHOD: One-year prospective study that included blood and sputum cultures, serologic studies, and detection of Legionella pneumophila and Streptococcus pneumoniae urinary antigens . RESULTS: 49 patients were recruited and an etiological diagnosis was attained in 34 (69%) . Microorganisms most frequently isolated were S . pneumoniae (12 cases), Mycoplasma pneumoniae (7), Haemophilus influenzae (4), respiratory viruses (4) and Coxiella burnetii (3 cases) . CONCLUSIONS: By means of a non-invasive protocol with urinary antigen tests, a microbial etiology can be established in two thirds of patients with mild CAP . S . pneumoniae is the main cause of mild CAP. S Afr Med J, 2001 Oct, 91(10), 864 - 9 A new combined DTP-HBV-Hib vaccine--strategy for incorporation of Hib vaccination into childhood immunisation programmes; Ramkissoon A et al.; OBJECTIVES: To evaluate the immunogenicity and reactogenicity of a pentavalent vaccine prepared by extemporaneously mixing diphtheria-tetanus pertussis-hepatitis B vaccine (DTP-HBV) and lyophilised Haemophilus influenzae type B (Hib)-tetanus conjugate vaccines in the same syringe, compared with the same vaccines given as separate, concomitant administrations . DESIGN: Open, randomised comparative study . SETTING: Durban, South Africa . SUBJECTS: A total of 120 healthy male and female infants were enrolled in the trial and randomised into two groups; group 1 received the combined administration (DTP-HBV-Hib), and group 2 received separate administrations of DTP-HBV and Hib vaccines . Vaccines were given as a three-dose primary vaccination course at 2, 4 and 6 months {corrected} of age . OUTCOME MEASURES: Antibody levels were measured using standard techniques and local and general solicited symptoms were recorded using diary cards . RESULTS: All subjects had seroprotective titres against diphtheria and tetanus; and antipolyribose-ribitol phosphate (PRP) titres > or = 0.15 microgram/ml 1 month after the final dose . A vaccine response (defined as post-vaccination titres > or = 15 ELISA (EL).U/ml in initially seronegative subjects; and as post-vaccination titres > or = pre-vaccination titres in initially seropositive subjects) against the pertussis component was seen in 83% and 85% of subjects in the groups receiving combined and separate administration . No differences were seen in any of the geometric mean titres (GMTs) between the two administrations either 2 months after the second dose or 1 month after the final dose . There was no observed increase in reactogenicity in the group receiving the mixed administration . CONCLUSIONS: The results demonstrate that combined DTP-HBV-Hib vaccine is well tolerated and immunogenic. Pediatrics . 2001 Dec;108(6):E112. Childhood vaccinations, vaccination timing, and risk of type 1 diabetes mellitus; DeStefano F et al.; OBJECTIVES: To evaluate suggested associations between childhood vaccinations, particularly against hepatitis B and Haemophilus influenzae type b, and risk of developing type 1 diabetes; and to determine whether timing of vaccination influences risk . METHODS: We conducted a case-control study within 4 health maintenance organizations (HMOs) that participate in the Vaccine Safety Datalink project of the Centers for Disease Control and Prevention . Study eligibility was restricted to children who met the following criteria: 1) born during 1988 through 1997; 2) HMO member since birth; 3) continuously enrolled for first 6 months of life; and 4) at least 12 months of HMO membership before diabetes incidence date (or index date for controls) unless incidence date was before 12 months of age . All 4 HMOs maintain registries of their members who have diabetes, and we used the registries to identify potential cases of diabetes . We conducted chart reviews to verify that potential cases met the World Health Organization epidemiologic case definition for type 1 diabetes mellitus (ie, a physician's diagnosis of diabetes plus treatment with daily insulin injections) . We defined the incidence date of diabetes as the first date that the child received a diagnosis of diabetes . We attempted to match 3 controls to each case . Controls had the same eligibility criteria as cases and were matched to individual cases on HMO, sex, date of birth (within 7 days), and length of health plan enrollment (up to the incidence or index date) . The index date for controls was defined as the incidence date of the case to which the control was matched . Chart abstraction was performed by trained chart abstractors using standardized forms . In addition to complete vaccination histories, the chart abstraction forms for both cases and controls included information on sociodemographic characteristics, selected medical conditions, history of breastfeeding, and family medical history . We used conditional logistic regression to estimate the odds ratio (OR) of diabetes associated with vaccination, with vaccine exposure defined as before the diabetes incidence date (or index date for controls) . RESULTS: Two hundred fifty-two confirmed cases of diabetes and 768 matched controls met the study eligibility criteria . The OR (95% confidence interval) for the association with type 1 diabetes was 0.28 (0.07-1.06) for whole cell pertussis vaccine (predominantly in combination as diphtheria, tetanus toxoids and pertussis vaccine), 1.36 (0.70-2.63) for measles-mumps-rubella, 1.14 (0.51-2.57) for Haemophilus influenzae type b, 0.81 (0.52-1.27) for hepatitis B vaccine, 1.16 (0.72-1.89) for varicella vaccine, and 0.92 (0.53-1.57) for acellular pertussis-containing vaccines . Compared with children who had not received hepatitis B vaccine, the OR of diabetes was 0.51 (0.23-1.15) for children vaccinated at birth and 0.86 (0.54-1.35) for those first vaccinated against hepatitis B at 2 months of age or later . Race and ethnicity and family history of diabetes were independently associated with risk of type 1 diabetes, but adjustment for these factors did not materially alter the ORs for any of the vaccines . CONCLUSIONS: In this large, population-based, case-control study, we did not find an increased risk of type 1 diabetes associated with any of the routinely recommended childhood vaccines . Our study adds to previous research by providing data on newer vaccines, including hepatitis B, acellular pertussis, and varicella vaccines . For the older vaccines, our results are generally in agreement with previous studies in not finding any increased risks . Ours is the first epidemiologic study to evaluate the possibility that timing of vaccination is related to risk of clinical diabetes in children . Our results on hepatitis B vaccine do not support the hypothesis; risk of type 1 diabetes was not different between infants vaccinated at birth and those who received their first vaccination later in life . The results of our study and the preponderance of epidemiologic evidence do not support an association between any of the recommended childhood vaccines and an increased risk of type 1 diabetes . Suggestions that diabetes risk in humans may be altered by changes in the timing of vaccinations also are unfounded. Clin Ther, 2001 Oct, 23(10), 1683 - 706 Diagnosis and treatment of upper respiratory tract infections in the primary care setting; Fendrick AM et al.; BACKGROUND: Acute respiratory tract infections such as acute exacerbations of chronic bronchitis (AECB), acute otitis media (AOM), and acute bacterial rhinosinusitis (ABRS) account for approximately 75% of antibiotic prescriptions written and are among the leading reasons for physician office visits in the United States . Resistance of the predominant pathogens in respiratory tract infections (Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis) to available antibiotics has led clinicians to reevaluate the diagnosis and management of these infections . OBJECTIVE: The purpose of this review is to provide primary care practitioners with an accessible combined resource for the management of AECB, AOM, and ABRS . METHODS: This review was based on discussions from a roundtable meeting (sponsored by an educational grant from GlaxoSmithKline) that convened clinicians versed in the management of upper and lower respiratory tract infections . In addition, primary articles were identified by a MEDLINE search and through secondary sources . RESULTS: To reduce the prevalence of resistance, judicious and appropriate use of antibiotics must be implemented in clinical practice . With accurate diagnosis of bacterial and nonbacterial conditions, and patient education on antibiotic use and misuse, the excessive use of antibiotics and ensuing resistance can be reduced . The incorporation of pharmacokinetic and pharmacodynamic data with minimum inhibitory concentration values can provide a more comprehensive assessment of antibiotic activity in vivo . Stratification of patients with AECB according to patient characteristics and frequency of exacerbation can be used to determine which patients will benefit from antibiotic treatment and to guide clinicians in their choice of antibiotic . The Drug-Resistant Streptococcus pneumoniae Therapeutic Working Group has issued recommendations on the management of AOM based on prior antibiotic therapy, which is a risk factor for antimicrobial resistance . The Sinus and Allergy Health Partnership guidelines for the treatment of ABRS in adults and children are based on the predicted efficacy of various antibiotics as well as patient age, severity of disease, likelihood of bacterial infection, likelihood of spontaneous resolution, and in vitro susceptibility of the predominant pathogens based on pharmacokinetic and pharmacodynamic breakpoints . CONCLUSIONS: Guidelines for the management of AECB, AOM, and ABRS emphasize the importance of differentiating between bacterial and nonbacterial infections, choosing an antibiotic based on the likelihood of infection with resistant pathogens, and providing coverage against the predominant pathogens . The judicious use of antibiotics also has been identified as an instrumental part of controlling unnecessary antibiotic use and subsequent resistance. J Clin Microbiol, 2001 Dec, 39(12), 4283 - 7 Standardization of broth microdilution and disk diffusion susceptibility tests for Actinobacillus pleuropneumoniae and Haemophilus somnus: quality control standards for ceftiofur, enrofloxacin, florfenicol, gentamicin, penicillin, tetracycline, tilmicosin, and trimethoprim-sulfamethoxazole; McDermott PF et al.; Quality control (QC) standards for the in vitro antimicrobial susceptibility testing of two fastidious veterinary pathogens, Actinobacillus pleuropneumoniae and Haemophilus somnus, were developed in a multilaboratory study according to procedures established by the National Committee for Clinical Laboratory Standards for broth microdilution and disk diffusion testing . The medium recommended for the broth microdilution testing is cation-adjusted Mueller-Hinton broth supplemented with 2% lysed horse blood, 2% yeast extract, and 2% supplement C . This medium has been designated veterinary fastidious medium . The medium recommended for the disk diffusion testing is chocolate Mueller-Hinton agar . The recommended QC organisms are A . pleuropneumoniae ATCC 27090 and H . somnus ATCC 700025 . The QC MICs of ceftiofur, enrofloxacin, florfenicol, gentamicin, penicillin, tetracycline, tilmicosin, and trimethoprim-sulfamethoxazole were determined for each isolate, as were the zone size ranges . Of the results from the participating laboratories, 94.0% of the zone diameter results and 97.0% of the MIC results fell within the suggested QC ranges for all compounds . These QC guidelines should allow greater accuracy in interpreting results when testing these antimicrobial agents against fastidious pathogens. Int J Infect Dis, 2001, 5(3), 139 - 43 Incidence of Chlamydia trachomatis and other potential pathogens in neonatal conjunctivitis; Di Bartolomeo S et al.; OBJECTIVE: Ocular infection in neonatology is a permanent and important health problem . To improve primary attention, prevention, and control, the study of the potential bacterial etiology of all consecutive cases of conjunctivitis was incorporated as a regular procedure in primary care from July 1995 to December 1998 . MATERIALS AND METHODS: Prof . A . Posadas Hospital (Great Buenos Aires) has an average of 4294 births per year . This report analyzes the results obtained in 332 infants (age range, 0-30 d) with conjunctivitis.Clinical conjunctivitis was diagnosed in inpatients and outpatients by the same specialized staff . Isolation and characterization of bacteria were done by conventional microbiologic methods, including specific search for Neisseria gonorrhoeae and Chlamydia trachomatis . Chlamydia trachomatis was studied by antigen immunodetection and polymerase chain reaction, and genotyped by restriction fragment length polymorphism . RESULTS: Conjunctivitis had an incidence (cases per 1000 live births) of 39.6 in 1995, 25.3 in 1996, 15.4 in 1997, and 15.2 in 1998 . Microbial growth was detected in 167 (50.3%) of 332 cases . Ocular C . trachomatis infection was detected in 26 cases (7.83%) . Five of seven isolates in tissue cultures belonged to type E and two to type G . Bacteria from respiratory ecology were the main isolates: Haemophilus influenzae (16.9%), Streptococcus pneumoniae (12.3%), and Staphylococcus aureus (8.7%) . Haemophilus influenzae isolates were not serotyped and 17.2% of them were b-lactamase producers . In 15 cases both H . influenzae and S . pneumoniae were isolated together . Of S . pneumoniae, 4.9% were oxacillin resistant . CONCLUSIONS: There has been a decline in the total number of cases of neonatal conjunctivitis, but the disease is still an important health problem . Chlamydia trachomatis also shows a decreasing profile with an incidence of (cases per 1000 live births) 4.39 in 1995, 1.85 in 1996, 1.01 in 1997, and 0.78 in 1998, and a tendency to show more incidence in spring-summer and significant accumulation of cases in babies between 7 and 9 days of age . Haemophilus influenzae alone (12.3%) or associated with S . pneumoniae (4.5%) appears as a prevalent potential bacterial pathogen . A significant accumulation of H . influenzae and S . pneumoniae cases occurs in winter . In 47.6% of cases, there was no bacterial growth . No significant seasonal differences in percentage of negative cultures or among the three-day age groups were detected . Neisseria gonorrhoeae was not found associated with ophthalmia neonatorum in this series. Int J Infect Dis, 2001, 5(3), 119 - 25 Impact of human immunodeficiency virus type 1 infection on the epidemiology and outcome of bacterial meningitis in South African children; Madhi SA et al.; OBJECTIVE: To define the impact that the human immunodeficiency virus type 1 (HIV-1) epidemic has had on the burden and outcome of bacterial meningitis in an area with a high prevalence of pediatric HIV-1 infection . METHODS: Children less than 12 years of age with proven or suspected bacterial meningitis were enrolled in this study between March 1997 and February 1999, and their hospital records were retrospectively reviewed for clinical data . RESULTS: Sixty-two (42.2%) of the 147 children tested for HIV-1 infection were infected . Streptococcus pneumoniae (Pnc) exceeded Haemophilus influenzae type b (Hib) as the most important cause of meningitis in HIV-1-infected (74.2% vs . 12.9%, respectively) compared with uninfected children (29.4% vs . 42.3%, respectively, P less than 10(-5)) . The estimated relative risk of Pnc meningitis was greater in HIV-1-infected than in uninfected children under 2 years of age (relative risk {RR} = 40.4; 95% confidence intervals {CI} = 17.7-92.2) . Overall, HIV-1-infected children had a higher rate of mortality than uninfected children (30.6% vs . 11.8%, respectively, P = 0.01), and in particular, HIV-1-infected children with Pnc meningitis (60.8% vs . 36.0%, respectively, P = 0.04) had a poorer outcome . CONCLUSIONS: Streptococcus pneumoniae has exceeded Hib as the most important pathogen causing bacterial meningitis in HIV-1-infected compared with uninfected children . Effective vaccination against Hib and Pnc should be evaluated to reduce the overall burden of bacterial meningitis in HIV-1-infected children. Biochemistry, 2001 Dec 4, 40(48), 14621 - 8 Mutagenesis identifies amino acid residues in extracellular loops and within the barrel lumen that determine voltage gating of porin from Haemophilus influenzae type b; Arbing MA et al.; Porin (341 amino acids; M(r) 37 782) of Haemophilus influenzae type b mediates exchange of solutes between the external environment and the periplasm of this Gram-negative bacterium . Positively charged residues in the extracellular loops have been shown to be involved in the voltage gating of this protein . To further elucidate our observations on the functional properties of this channel, we mutated seven lysines (Lys(48), Lys(161), Lys(165), Lys(170), Lys(248), Lys(250), and Lys(253)) to glutamic acid . The selected residues were previously shown to be accessible to chemical modification, and they map to three locations: loop 4 and loop 6, and within the barrel lumen . The seven mutant proteins were purified, and each was reconstituted into planar lipid bilayers to characterize its channel forming properties . The single substitution mutant porins displayed increased single channel conductances in 1 M KCl ranging between 134 and 178% of the single channel conductance for wild-type Hib porin . Six of the seven mutant porins also displayed altered current-voltage relationships when compared to wild-type Hib porin . Whereas Lys(170)Glu had activity similar to wild-type Hib porin, Lys(48)Glu, Lys(248)Glu, and Lys(253)Glu showed substantial voltage gating at both positive and negative polarities . Lys(161)Glu and Lys(250)Glu gated only at negative potentials, and Lys(165)Glu gated only at positive potentials . Rather than ascribing one specific loop in gating, our analyses of these mutant Hib porins suggest that voltage gating can be attributed to contributions from loops 4 and 6 and a residue within the barrel lumen. J Vet Diagn Invest, 2001 Nov, 13(6), 495 - 501 Development of a PCR test to diagnose Haemophilus parasuis infections; Oliveira S et al.; A polymerase chain reaction (PCR) test was developed in order to improve the accuracy and speed of diagnosis of Haemophilus parasuis, an economically important respiratory pathogen that affects swine . The gene sequence of the 16S small subunit ribosomal RNA of H . parasuis (GenBank M75065) was compared with 56 16S sequences of related bacteria, including those frequently isolated from pig tissues . Two species-specific primers were designed: HPS forward and HPS reverse . The predicted size of the amplified PCR product was 821 bp . The PCR test could detect a minimum of 102 bacteria and 0.69 pg of DNA . Thirty-one H . parasuis isolates, including 12 different serovars and 19 field isolates, were positive using the PCR test . No amplification was observed when the test was run using DNA from 15 other bacterial species commonly isolated from swine tissues . A weak band was observed when the PCR test was performed using Actinobacillus indolicus DNA as template . Clinical samples tested by PCR included tissues and swabs from 5 animals naturally infected with H . parasuis and 1 experimentally infected animal . The PCR was positive in 26 of 30 clinical samples . Four samples showed weak bands, and these results were not considered positive . Haemophilus parasuis was isolated from 18 of 30 of these samples . Tissues from specific pathogen-free (SPF) pigs and from unrelated species were negative for H . parasuis isolation and PCR . The developed PCR was successfully used in the diagnosis of H . parasuis infection, especially when compared with traditional microbiology techniques. Clin Infect Dis, 2001 Dec 15, 33 Suppl 4, S278 - 87 Assessing efficacy of Haemophilus influenzae type b combination vaccines; Granoff DM; Regulatory approval of diphtheria and tetanus toxoids and acellular pertussis (DTaP)-based combination vaccines containing Haemophilus influenzae type b (Hib) has been delayed in the US because of difficulty in assessing the effect of lower Hib immunogenicity on vaccine efficacy compared with the immunogenicity of the specific Hib component administered separately . Hib conjugate vaccines confer protection by eliciting serum anticapsular antibody and priming for immunologic memory . Therefore, compelling proof of efficacy would be demonstration that a combination vaccine primes for memory and elicits antibody responses that are not inferior to those elicited by other US-licensed Hib conjugate vaccines, not necessarily the specific Hib component used in the combination . Vaccinated infants also can be considered protected if their serum anticapsular antibody concentrations are > or =0.15 microg/mL immediately before the booster dose given in the second year of life, when antibody concentrations are lowest . These alternative serologic approaches offer a strong scientific and regulatory rationale for licensure of effective DTaP-based Hib combination vaccines. Acta Crystallogr D Biol Crystallogr, 2001 Dec, 57(Pt 12), 1950 - 4 Epub 2001 Nov 21. Structure of Haemophilus influenzae HslV protein at 1.9 A resolution, revealing a cation-binding site near the catalytic site; Sousa MC et al.; The structure of the Haemophilus influenzae HslV protease of the HslUV 'prokaryotic proteasome' has been solved by molecular replacement and refined with data to 1.9 A resolution . The protease is a 'double donut' of hexameric rings; two alternative sets of intermolecular interactions between protomers in the rings result in 'quasi-equivalent' packing within the assembly . Anomalous scattering data from crystals with potassium present in the mother liquor reveal a K(+) ion bound with octahedral coordination near the active-site Thr1 residue . The site also binds Na(+) ions and is likely to bind Mg(2+), suggesting that monovalent and divalent metal ions may influence the catalytic activity of the protease. J Bacteriol, 2001 Dec, 183(24), 7206 - 12 Redox signal transduction by the ArcB sensor kinase of Haemophilus influenzae lacking the PAS domain; Georgellis D et al.; The Arc (anoxic redox control) two-component signal transduction system of Escherichia coli, which comprises the tripartite ArcB sensor kinase and the ArcA response regulator, modulates the expression of numerous operons in response to redox conditions of growth . We demonstrate that the arcA and arcB genes of Haemophilus influenzae specify a two-component system . The Arc proteins of the two bacterial species sufficiently resemble each other that they can participate in heterologous transphosphorylation in vitro . Moreover, the Arc system of H . influenzae mediates transcriptional control according to the redox condition of growth both autologously in its own host and homologously in E . coli, indicating a high degree of functional conservation of the signal transduction system . The H . influenzae ArcB, however, lacks the PAS domain present in the region of E . coli ArcB linking the transmembrane to the cytosolic catalytic domains . Because the PAS domain participates in signal reception in a variety of sensory proteins, including sensors of molecular oxygen and redox state, a similar role was previously ascribed to it in ArcB . Our results demonstrate that the ArcB protein of H . influenzae mediates signal transduction in response to redox conditions of growth despite the absence of the PAS domain. J Pediatr, 2001 Nov, 139(5), 624 - 9 An analysis of the immunization status of preschool children enrolled in a statewide Medicaid managed care program; Vivier PM et al.; OBJECTIVES: To measure immunization coverage rates for children enrolled in a statewide Medicaid managed care program and determine the impact of sociodemographic characteristics and the type of primary care provider site on immunization coverage . STUDY DESIGN: A random sample of 2000 was chosen from children between the ages of 19 and 35 months who had been continuously enrolled in the Medicaid managed care program for 1 year . Sociodemographic data and a list of primary care providers for the study children were obtained from administrative databases . Immunization histories were determined by medical record review . RESULTS: Vaccine-specific immunization rates for diphtheria-tetanus-pertussis, polio, Haemophilus influenzae type b, hepatitis B, and measles-mumps-rubella ranged from 87% to 94%, with an overall coverage rate of 75% . Overall immunization status varied by primary care provider site as follows: office-based, 72%; community health center, 75%; hospital-based clinic, 79%; and staff model health maintenance organization, 85% (chi(2) test, P =.008) . CONCLUSIONS: Immunization rates compare favorably with national rates for this low-income group . Sociodemographic characteristics were not important predictors of underimmunization, but rates did vary by the type of primary care provider site. Bioorg Med Chem, 2001 Dec, 9(12), 3243 - 53 Carbon-carbon-linked (pyrazolylphenyl)oxazolidinones with antibacterial activity against multiple drug resistant gram-positive and fastidious gram-negative bacteria; Lee CS et al.; In an effort to expand the spectrum of activity of the oxazolidinone class of antibacterial agents to include Gram-negative bacteria, a series of new carbon-carbon linked pyrazolylphenyl analogues has been prepared . The alpha-N-substituted methyl pyrazole (10alpha) in the C3-linked series exhibited very good Gram-positive activity with MICs <or=0.5-1 microg/mL and moderate Gram-negative activity with MICs=2-8 microg/mL against Haemophilus influenzae and Moraxella catarrhalis . This analogue was also found to have potent in vivo activity with an ED(50)=1.9 mg/kg . Beta-substitution at the C3-linked pyrazole generally results in a loss of activity . The C4-linked pyrazoles are slightly more potent than their counterparts in the C3-linked series . Most of the analogues in the C4-linked series exhibited similar levels of activity in vitro, but lower levels of activity in vivo than 10alpha . In addition, incorporation of a thioamide moiety in selected C4-linked pyrazole analogues results in an enhancement of in vitro activity leading to compounds several times more potent than eperezolid, linezolid and vancomycin . The thioamide of the N-cyanomethyl pyrazole analogue (34) exhibited an exceptional in vitro activity with MICs of <or= 0.06-0.25 microg/mL against Gram-positive pathogens and with MICs of 1 microg/mL against fastidious Gram-negative pathogens. Antimicrob Agents Chemother, 2001 Dec, 45(12), 3613 - 5 Postantibiotic effects of ABT-773 and amoxicillin-clavulanate against Streptococcus pneumoniae and Haemophilus influenzae; Neuhauser MM et al.; This study determined the postantibiotic effect (PAE) of ABT-773 versus that of amoxicillin-clavulanate against clinical isolates of Streptococcus pneumoniae and Haemophilus influenzae . The PAEs of ABT-773 and amoxicillin-clavulanate ranged from 2.3 to 6.0 h and 0 to 2.2 h against S . pneumoniae and from 2.7 to 9.1 h and 0 to 0.8 h against H . influenzae, respectively. Antimicrob Agents Chemother, 2001 Dec, 45(12), 3437 - 44 P-113D, an antimicrobial peptide active against Pseudomonas aeruginosa, retains activity in the presence of sputum from cystic fibrosis patients; Sajjan US et al.; Antimicrobial peptides are a source of novel agents that could be useful for treatment of the chronic lung infections that afflict cystic fibrosis (CF) patients . Efficacy depends on antimicrobial activity against the major pathogens of CF patients, Pseudomonas aeruginosa, Staphylococcus aureus, and Haemophilus influenzae, in the environment of the CF patient's airway . We describe the in vitro efficacies of derivatives of histatins, which are histidine-rich peptides produced by the salivary glands of humans and higher primates . P-113, a peptide containing 12 of the 24 amino acid residues of the parent molecule, histatin 5, retained full antibacterial activity and had a good spectrum of activity in vitro against the prominent pathogens of CF patients . However, P-113 was not active in the presence of purulent sputum from CF patients . In contrast, P-113D, the mirror-image peptide with the amino acid residues in the D configuration, was stable in sputum, was as active as P-113 against pathogens of CF patients in the absence of sputum and retained significant activity in the presence of sputum from CF patients . Recombinant human DNase, which effectively liquefies sputum, enhanced the activity of P-113D in undiluted sputum against both exogenous (added) bacteria and endogenous bacteria . Because of its properties, P-113D shows potential as an inhalant in chronic suppressive therapy for CF patients. Can Vet J, 2001 Nov, 42(11), 857 - 60 The immunohistochemical detection of Mycoplasma bovis and bovine viral diarrhea virus in tissues of feedlot cattle with chronic, unresponsive respiratory disease and/or arthritis; Haines DM et al.; The purpose of this study was to determine the frequency of selected pathogens in the tissues of a group of feedlot cattle with chronic disease (most often respiratory disease and/or arthritis) . Samples of lung and joint tissues from 49 feedlot animals that had failed to respond to antibiotic therapy were tested by immunohistochemical staining for the antigens of Mycoplasma bovis, Haemophilus somnus, Pasteurella (Mannheimia) hemolytica, and bovine viral diarrhea virus (BVDV) . Mycoplasma bovis was demonstrated in over 80% of cases, including in 45% of joints and 71% of lungs tested . Mycoplasma bovis was the only bacterial pathogen identified in the joints . Haemophilus somnus and Pasteurella (Mannheimia) haemolytica were found in 14% and 23% of cases, respectively, and were confined to the lungs in all instances . Infection with BVDV was demonstrated in over 40% of cases . Mycoplasma bovis and BVDV were the most common pathogens persisting in the tissues of these animals that had failed to respond to antibiotic therapy. Infect Immun, 2001 Dec, 69(12), 7293 - 303 Nonimmune binding of human immunoglobulin A (IgA) and IgG Fc by distinct sequence segments of the EibF cell surface protein of Escherichia coli; Sandt CH et al.; The eib genes of Escherichia coli encode surface-exposed proteins which bind immunoglobulins (Ig) such as the Fc fragment of human IgG (IgG Fc) in a nonimmune manner . The Eib proteins belong to a family which includes YadA of Yersinia, UspA2 of Moraxella, and DsrA of Haemophilus ducreyi . This family of surface-exposed proteins shares several features, such as the ability to impart resistance to human serum complement and a tendency to exist as stable multimers . Four genes, eibA, eibC, eibD and eibE, were previously identified and cloned from ECOR-9, a strain from the E . coli reference collection . EibC, -D, and -E bind human serum IgA in addition to IgG, but no IgA binding has been observed for EibA . Here, we report the cloning of a new eib gene, eibF, from a second strain of E . coli, ECOR-2 . The product, EibF, has a relatively strong preference for IgA . Like the other eib genes, eibF attenuates serum sensitivity, occurs as a stable multimer, and is associated with a prophage . By subcloning portions of the eibA and eibF genes, we have identified distinct sequence segments sufficient to cause Ig binding, multimerization, and discrimination between IgA and IgG . The ability to multimerize is associated with a sequence close to the C terminus that is homologous to other family members such as YadA . Binding of IgG Fc is associated with a sequence that is highly conserved among all Eib proteins but otherwise unique . Binding of IgA is associated with a sequence of EibF that is not similar to any EibA sequence. Neth J Med, 2001 Nov, 59(5), 213 - 7 Capnocytophaga canimorsus sepsis presenting as an acute abdomen in an asplenic patient; Depres-Brummer P et al.; Acute abdominal symptoms are frequently caused by surgical intra-abdominal problems . However, the differential diagnosis also includes several internal diseases . Overwhelming infections may present with acute abdominal signs, particularly in the immunocompromised host . Asplenic patients are highly susceptible to infections with encapsulated bacteria such as Streptococcus pneumoniae, Haemophilus influenzae and Neisseria meningitidis . Severe infections due to Capnocytophaga canimorsus (DF2), are also common in this group . C . canimorsus is a Gram-negative rod, present as a commensal organism in cat and dog saliva . We describe the atypical presentation of a fatal C . canimorsus-sepsis in a 46-year-old man, who underwent traumatic splenectomy two decades earlier. Pediatr Infect Dis J, 2001 Nov, 20(11 Suppl), S45 - 56 "Reverse engineering" a formulary selection algorithm to determine the economic value of pentavalent and hexavalent combination vaccines; Sewell EC et al.; INTRODUCTION: Combination vaccines with overlapping, noncomplementary components are being introduced to reduce the number of separate injections required to immunize children . A vaccine selection algorithm using operations research techniques was developed as a tool for vaccine purchasers to assemble formularies of monovalent and combination vaccines that would satisfy the recommended immunization schedule . The algorithm weighs distinguishing features of economic consequence among competing vaccines to achieve the lowest overall cost to payers and/or to society for immunization . This method was adapted here to solve for the purchase price of several hypothetical future pentavalent and hexavalent combination vaccines that would permit each to "win" a place in such a lowest cost formulary . METHODS: Integer programming and an iterative bisection search method determined the maximum "inclusion price" of 4 vaccines not licensed in the United States as of September, 2001 {diphtheria-tetanus-acellular pertussis (DTPa)-Haemophilus influenzae type b (HIB)-hepatitis B (HBV), DTPa-HIB-inactivated polio vaccine (IPV), DTPa-HBV-IPV and DTPa-HIB-HBV-IPV}, in competition with 15 existing formulations of licensed vaccines for these diseases at their March, 2000, federal contract discount prices . Both 5-visit and 6-visit scenarios were studied . Different preparation costs were assigned to lyophilized powder ($1.50), liquid ($0.75) and prefilled-syringe ($0.25) formulations/packaging . Injection costs were varied stepwise from $5 through $45 for each dose administered, shifting from a payer's to a societal perspective . RESULTS: Overall inclusion prices (maximum price for each candidate vaccine to be included in a lowest cost formulary) ranged from $9 to $129 per dose depending on cost assumptions and usage frequency (values would be higher if competing against private-sector vaccine prices) . The range was $27 to $68 per dose for DTPa-HIB-HBV, at optimal utilization to avoid extra vaccination . Similarly, as injection costs varied from $5 to $45, DTPa-HIB-IPV ranged from $28 to $75 . With the same assumptions, DTPa-HBV-IPV would earn a place in a best value formulary at prices from $35 to $76 . As expected the inclusion prices for hexavalent DTPa-HIB-HBV-IPV, $40 to $123, were higher (reflecting more economic value) than for pentavalents . When the assumed injection costs rose to > or = $8, the more expensive HIB-HBV and DTPa-HIB tended to appear in lowest cost formularies, because their cost premium over separate monovalent and trivalent products was outweighed by the savings from one fewer injection . CONCLUSION: Reverse engineering the vaccine selection algorithm provides a tool to demonstrate the economic value of new combination vaccines and to make pricing decisions. Pediatr Infect Dis J, 2001 Nov, 20(11 Suppl), S30 - 3 Hepatitis B vaccination coverage among United States children; Yusuf H et al.; BACKGROUND: In 1991 the Advisory Committee on Immunization Practices recommended vaccination of all infants with three doses of hepatitis B virus vaccine (HepB) by 18 months of age as a key component of a comprehensive strategy to eliminate hepatitis B virus transmission in the United States . The American Academy of Pediatrics and the American Academy of Family Physicians published similar recommendations soon afterward . METHODS: Data were obtained from the National Immunization Survey, a survey that began in 1994 and is conducted quarterly by the Centers for Disease Control and Prevention to estimate vaccination coverage among noninstitutionalized US children 19 to 35 months of age . RESULTS: The 1999 National Immunization Survey data indicate that approximately 88.1% (95% confidence interval, 87.4, 88.8) of children 19 to 35 months of age had received at least three doses of HepB (HepB3) . There has been a consistent increase in HepB3 coverage since 1994 . However, the rate of increase has slowed in recent years and HepB3 coverage remains lower than coverage attained with three doses of diphtheria-tetanus-pertussis and Haemophilus influenzae vaccines . HepB3 coverage varied slightly by race/ethnicity and was highest among white and Asian children (89%) . Coverage also varied by state; 26 states had levels of at least 90% . CONCLUSIONS: Since the 1991 recommendations for universal hepatitis B vaccination, there has been a dramatic increase in coverage levels among children 19 to 35 months of age . However, the Childhood Immunization Initiative goal of 90% coverage has not been reached . Therefore continued efforts are needed to protect US children against this serious but preventable infection. Pediatr Infect Dis J, 2001 Nov, 20(11 Suppl), S23 - 9 Interchangeability of vaccines; Feldman S; BACKGROUND: The delivery of childhood immunizations can be complex, often requiring numerous injections over months or years to complete the recommended schedule . The ability to interchange similar vaccines from different manufacturers during a vaccination series is important because the product administered previously may be unknown or no longer available . METHODS: The current vaccine literature was reviewed to identify available data and determine the consensus on the interchangeability of current vaccines . RESULTS: In the instance of diphtheria-tetanus toxoids-acellular pertussis (DTPa) vaccine, no serologic markers of protective efficacy against Bordetella pertussis exist; therefore it is difficult to evaluate interchangeability of available products . Consequently the ACIP, AAP and AAFP have recommended that the same DTPa product be used for the first three doses of the immunization series . However, if the previously administered product is unknown or not readily available, any licensed DTPa product may be used . More recent data suggest that at least some of the DTPa products have similar immunogenicity and appear to be interchangeable . For other families of vaccines, such as those designed to prevent infection with hepatitis B virus, poliovirus and Haemophilus influenzae type b, there is good evidence attesting to sustained immunogenicity when products from different manufacturers are used to complete a series . CONCLUSIONS: The use of approved combination vaccine products whenever possible is advocated by the ACIP, AAP and AAFP because such products decrease the number of injections needed to complete the recommended immunizations and may reduce health care costs, improve program performance and aid in documentation of administered vaccines. Pediatr Infect Dis J, 2001 Nov, 20(11 Suppl), S10 - 8 Principles of pediatric combination vaccines and practical issues related to use in clinical practice; Decker MD; BACKGROUND: During the past two decades the number of injections that are required per office visit to fulfill the recommended childhood immunization schedule has increased dramatically . METHODS: By reviewing the literature, the principles associated with pediatric combination vaccines are discussed, and practical issues related to their use in clinical practice are evaluated . RESULTS: The ideal combination vaccine is safe, effective and easy to store and use, and its antigenic components fit within the recommended immunization schedule . The ideal combination is associated with fewer adverse reactions than the separately administered antigens, with improved efficacy and higher immune responses compared with its component vaccines . An acceptable combination vaccine must provide comparable efficacy and safety to its component vaccines . Although there are a limited number of combination vaccines already available {diphtheria-tetanus-pertussis, inactivated poliovirus vaccine (IPV) and measles-mumps-rubella}, effort is being focused on combining these vaccines with other routine vaccines of infancy including Haemophilus influenzae type b (Hib) and hepatitis B vaccine (HepB) . Currently under review by the Food and Drug Administration are diphtheria-tetanus-acellular pertussis (DTPa)-HepB-IPV and DTPa-Hib-IPV combination vaccines, and two DTPa-HepB-IPV-Hib vaccines have been licensed in Europe . As more combination vaccines become available, issues such as interchangeability and administration of extra doses are raised; however, it is important not to miss a vaccination opportunity . CONCLUSIONS: The number of injections required to fulfill the recommended childhood immunization schedule at each visit creates problems for patients and practitioner, sometimes risking a missed opportunity for vaccination . The development of combination vaccines will circumvent this problem and increase compliance and vaccination coverage rates. Rev Panam Salud Publica, 2001 Sep, 10(3), 169 - 73 {Impact of vaccination against Haemophilus influenzae type b in Cuba}; Dickinson FO et al.; OBJECTIVE: To assess the effectiveness of mass vaccination in Cuba of children under 2 years of age against Haemophilus influenzae type b (Hib), the most common causative pathogen of bacterial meningitis . METHODS: The availability of effective Hib conjugate vaccines led to a nationwide vaccination program in 1999 targeting all children under 2 years of age, with a 97% coverage rate achieved . To assess the program's impact, data from 1998 and 1999 from the National Bacterial Meningitis Reporting System were used . RESULTS: Vaccination efficacy was estimated at 99% . The overall incidence of Hib meningitis declined 46.1%, from 1.3 to 0.6 cases per 100,000 population . The greatest overall reduction, of 56.1%, occurred among children under 5 years of age . Among children under 1 year of age, the reduction was 70.5%, and among the rest of the age groups of children under 5, incidence decreased between 25.9% and 49.6% . In the group targeted for vaccination, incidence decreased 61.1% . Among children in the target group who contracted Hib meningitis, only 8 cases (24.2%) had been vaccinated, most with a single dose applied 1 month before becoming ill . CONCLUSIONS: Hib vaccination of all children under 2 years of age in Cuba greatly reduced the incidence of Hib meningitis, as measured by the National Bacterial Meningitis Reporting System. Annu Rev Genomics Hum Genet, 2000, 1, 99 - 116 How many genes can make a cell: the minimal-gene-set concept; Koonin EV; Several theoretical and experimental studies have endeavored to derive the minimal set of genes that are necessary and sufficient to sustain a functioning cell under ideal conditions, that is, in the presence of unlimited amounts of all essential nutrients and in the absence of any adverse factors, including competition . A comparison of the first two completed bacterial genomes, those of the parasites Haemophilus influenzae and Mycoplasma genitalium, produced a version of the minimal gene set consisting of approximately 250 genes . Very similar estimates were obtained by analyzing viable gene knockouts in Bacillus subtilis, M . genitalium, and Mycoplasma pneumoniae . With the accumulation and comparison of multiple complete genome sequences, it became clear that only approximately 80 genes of the 250 in the original minimal gene set are represented by orthologs in all life forms . For approximately 15% of the genes from the minimal gene set, viable knockouts were obtained in M . genitalium; unexpectedly, these included even some of the universal genes . Thus, some of the genes that were included in the first version of the minimal gene set, based on a limited genome comparison, could be, in fact, dispensable . The majority of these genes, however, are likely to encode essential functions but, in the course of evolution, are subject to nonorthologous gene displacement, that is, recruitment of unrelated or distantly related proteins for the same function . Further theoretical and experimental studies within the framework of the minimal-gene-set concept and the ultimate construction of a minimal genome are expected to advance our understanding of the basic principles of cell functioning by systematically detecting nonorthologous gene displacement and deciphering the roles of essential but functionally uncharacterized genes. IUBMB Life, 2001 May, 51(5), 321 - 7 Remarkable conservation of translation initiation factors: IF1/eIF1A and IF2/eIF5B are universally distributed phylogenetic markers; Sorensen HP et al.; Initiation of protein biosynthesis is an essential process occurring in cells throughout the three phylogenetic domains, Bacteria, Archaea, and Eucarya . IF1/eIF1A and IF2/eIF5B, two conserved translation initiation factors are involved in this important step of protein biosynthesis . The essentiality, universal distribution, conservation, and interspecies functional homology of both factors are a unique combination of properties ideal for molecular phylogenetic studies as demonstrated by the extensively compared SSU rRNAs . Here, we assess the use of IF1/eIF1A and IF2/eIF5B in universal and partial phylogenetic studies by comparison of sequence information from species within all three phylogenetic domains and among closely related strains of Haemophilus parainfluenzae . We conclude that the amino acid sequence of IF1/eIF1A-IF2/eIF5B is a universal phylogenetic marker and that the nucleotide sequence of the IF2/eIF5B G-domain is more credible than SSU rRNA for the construction of partial phylogenies among closely related species and strains . Because of these two application levels, IF1/eIF1A-IF2/eIF5B is a phylogenetic "dual level" marker. J Biol Chem, 2002 Jan 11, 277(2), 949 - 57 Epub 2001 Nov 06. Novel cytoplasmic proteins of nontypeable Haemophilus influenzae up-regulate human MUC5AC mucin transcription via a positive p38 mitogen-activated protein kinase pathway and a negative phosphoinositide 3-kinase-Akt pathway; Wang B et al.; Nontypeable Haemophilus influenzae (NTHi) is an important human pathogen that causes chronic otitis media with effusion (COME) in children and exacerbation of chronic obstructive pulmonary disease (COPD) in adults . Mucin overproduction, a hallmark of both diseases, has been shown to directly cause conductive hearing loss in COME and airway obstruction in COPD . The molecular mechanisms underlying mucin overproduction in NTHi infections still remain unclear . Here, we show that NTHi strongly up-regulates MUC5AC mucin transcription only after bacterial cell disruption . Maximal up-regulation is induced by heat-stable bacterial cytoplasmic proteins, whereas NTHi surface membrane proteins induce only moderate MUC5AC transcription . These results demonstrate an important role for cytoplasmic molecules from lysed bacteria in the pathogenesis of NTHi infections, and may well explain why many patients still have persistent symptoms such as middle ear effusion in COME after intensive antibiotic treatment . Furthermore, our results indicate that activation of p38 mitogen-activated protein kinase is required for NTHi-induced MUC5AC transcription, whereas activation of phosphoinositide 3-kinase-Akt pathway leads to down-regulation of NTHi-induced MUC5AC transcription via a negative cross-talk with p38 mitogen-activated protein kinase pathway . These studies may bring new insights into molecular pathogenesis of NTHi infections and lead to novel therapeutic intervention for COME and COPD. J Biomol Struct Dyn, 2001 Oct, 19(2), 201 - 13 Computer modeling of small heat-shock metalloprotease of the human malaria parasite Plasmodium vivax; Kothekar V et al.; We present here computer generated model of N-terminal fragment, amino acids (aa) 36-245, of a Plasmodium vivax heat shock metalloprotease called PVHSP28, whose gene was cloned and characterised earlier . The fragment showed homology with HSPs from many organisms, including Escherichia coli and Haemophilus influenzae . PVHSP28 had the signature sequence 'HEXXH' and 'EXXXD' of Zinc metalloproteases . Being the first malarial HSP possessing metalloprotease activity, PVHSP28 is an ideal target for the design of new anti-malarial drugs . However, except for a small region (aa 62-132) which had 24.6% sequence similarity with 1TAQ (a DNA polymerase), it did not show sequence similarity with any published structures in protein data bank . Hence it could not be modelled using any automated modeling programs . We modelled 36-245 aa of PVHSP28 using predicted secondary structure as well as experimentally determined and predicted properties of the protein on the basis of its amino acid sequence, using various Internet tools and in-house package MODEL . The model was energy minimised using Sander's module of AMBER 5.0, working on a Silicon Graphics machine, with all atom force field. Pediatrics, 2001 Nov, 108(5), 1169 - 74 Lumbar puncture in pediatric bacterial meningitis: defining the time interval for recovery of cerebrospinal fluid pathogens after parenteral antibiotic pretreatment; Kanegaye JT et al.; OBJECTIVE: Despite the lack of evidence defining a time interval during which cerebrospinal fluid (CSF) culture yield will not be affected by previous antibiotic therapy, recent publications cite a "minimum window" of 2 to 3 hours for recovery of bacterial pathogens after parenteral antibiotic administration . We conducted a retrospective review of children with bacterial meningitis to describe the rate at which parenteral antibiotic pretreatment sterilizes CSF cultures . METHODS: The medical records of pediatric patients who were discharged from a tertiary children's hospital during a 5-year period with the final diagnosis of bacterial meningitis or suspected bacterial meningitis were reviewed . The decay in yield of CSF cultures over time was evaluated in patients with lumbar punctures (LP) delayed until after initiation of parenteral antibiotics and in patients with serial LPs before and after initiation