Appl Environ Microbiol, 1999 Jan, 65(1), 221 - 30 Production of wax esters during aerobic growth of marine bacteria on isoprenoid compounds Rontani JF, Bonin PC, Volkman JK. This paper describes the production of isoprenoid wax esters during the aerobic degradation of 6,10,14-trimethylpentadecan-2-one and phytol by four bacteria (Acinetobacter sp . strain PHY9, Pseudomonas nautica {IP85/617}, Marinobacter sp . strain CAB {DSMZ 11874}, and Marinobacter hydrocarbonoclasticus {ATCC 49840}) isolated from the marine environment . Different pathways are proposed to explain the formation of these compounds . In the case of 6,10, 14-trimethylpentadecan-2-one, these esters result from the condensation of some acidic and alcoholic metabolites produced during the biodegradation, while phytol constitutes the alcohol moiety of most of the esters produced during growth on this isoprenoid alcohol . The amount of these esters formed increased considerably in N-limited cultures, in which the ammonium concentration corresponds to conditions often found in marine sediments . This suggests that the bacterial formation of isoprenoid wax esters might be favored in such environments . Although conflicting evidence exists regarding the stability of these esters in sediments, it seems likely that, under some conditions, bacterial esterification can enhance the preservation potential of labile compounds such as phytol. Med Dosw Mikrobiol, 1998, 50(1-2), 9 - 19 {Utilization of siderophores from the Acinetobacter genus by staphylococcal bacilli}; Szarapinska-Kwaszewska J et al.; The ability of iron utilizing by means of siderophores produced by donor strains--the members of the genus Acinetobacter (8 strains) by 24 staphylococcal strains was investigated . All the donor strains synthesized hydroxamate class siderophores and six strains also catecholate class . The majority of staphylococcal strains could utilize these siderophores . Most strains utilized siderophores from A . juni 321 and A . johnsonii 349 strains . Only three staphylococcal strains were not be able to utilize siderophores from all donor strains. Zentralbl Veterinarmed B, 1998 Nov, 45(9), 551 - 9 {Model investigations of the impedance effectiveness conerning bacterial relevant to food hygiene}; Schulenburg J et al.; The impedance technique mostly meets today's requirements of microbiological rapid methods . At relatively high prime cost for the equipment the advantages are marked by low personnel and material costs as well as swiftness combined with highly flexible usage . The method is applicable for both quantitative and qualitative examinations but can fail occasionally in total count determination, especially if the sample material contains heterogeneous microbes . In model investigations with 53 strains of 17 different genera Enterobacteriaceae strains, Aeromonads and Enterococcus strains proved to be highly impedance effective . Lactobacillus strains and Pseudomonads as well as Staphylococcus aureus strains showed a low impedance effectiveness . Several strains, for example of the genera Micrococcus, Acinetobacter and Brochothrix, did not show any changes of the medium impedance under the chosen conditions . Criterion for characterization of impedance effectiveness was the impedance detection time starting with identical initial counts (10(3) cfu/ml) . Impedance effectiveness of microbes was determined at highly varying degree by the parameters of generation time, lag-phase duration and relative activity . This can lead either to wrong negative (underestimations) or wrong positive (overestimations) results of bacterial count. Rev Assoc Med Bras, 1998 Oct-Dec, 44(4), 283 - 8 {In vitro antimicrobial activity of cefpirome compared to other broad-spectrum beta-lactam drugs against 804 clinical isolates from 9 Brazilian hospitals}; Sader HS et al.; OBJECTIVE: To evaluate the in vitro activity of the fourth-generation cephalosporin cefpirome in comparison to that of ceftazidime, ceftriaxone, cefotaxime and imipenem in a multicenter study involving nine hospitals from six cities (four States) . MATERIAL AND METHOD: A total of 804 isolates from patients hospitalized in either intensive care units or Oncology/Hematology units was evaluated . The isolates were collected between June and November of 1995, i.e . before cefpirome became commercially available in Brazil, and susceptibility tested by broth microdilution following the NCCLS procedures . All isolates resistant to cefpirome were retested by E-test . RESULTS: Against Enterobacteriaceae (n = 344), cefpirome demonstrated an activity 2 to 32-fold higher than that of the third-generation cephalosporins (TGCs) and similar to that of imipenem . The percentages of Enterobacteriaceae susceptible were: 88%, 69% and 96% for cefpirome, TGCs and imipenem, respectively . The cefpirome spectrum was greater or equal than that of imipenem against Citrobacter freundii, Enterobacter aerogenes, Morganella morganii and Serratia marcescens . Against Acinetobacter sp . (n = 77), cefpirome was slightly more active than ceftazidime; however, the percentages of isolates resistant to these compounds were high (84% and 88%, respectively) . The activities of cefpirome, ceftazidime and imipenem were very similar against P . aeruginosa isolates (n = 128), with MIC50(mg/ml)/percent susceptible of 8/59%, 8/62% and 4/62% respectively . Against aerobic gram-positive bacteria, the cefpirome activity was 4 to 16-fold higher than that of TGCs but 2 to 8-fold lower than that of imipenem . CONCLUSION: The results suggest that, in Brazil, cefpirome has a spectrum of activity which is higher than that of the TGCs against aerobic gram-negative (Enterobacteriaceae and non-Enterobacteriaceae) and gram-positive bacteria and similar to that of imipenem against some Enterobacteriaceae species and P . aeruginosa. Acta Microbiol Pol, 1998, 47(2), 213 - 7 Electron-microscopic observation of adherence of Acinetobacter baumannii to red blood cells; Gospodarek E et al.; It is now recognized that Acinetobacter spp . play a significant role in the colonization and infection of patients admitted to hospitals . The virulence factors of A . baumannii remains largery unknown . In this study, the adherence of A . baumannii to several species of red blood cells was investigated . The ruthenium red staining was used for electron microscopic studies . The results obtained in electron microscopy and the hemagglutination studies suggested that the thin and long fimbriae of A . baumannii participated in adhesion of these bacteria to red blood cells. Am J Infect Control, 1998 Dec, 26(6), 552 - 7 Low-level colonization and infection with ciprofloxacin-resistant gram-negative bacilli in a skilled nursing facility; Lee YL et al.; BACKGROUND: We report a 1-year surveillance study that evaluates colonization and infection with ciprofloxacin-resistant gram-negative bacilli (CR GNB) and the relation to quinolone use and other possible risk factors in a proprietary skilled nursing facility (SNF) with no history of outbreaks . METHODS: Rectal swabs obtained quarterly were streaked on MacConkey agar with ciprofloxacin discs (5 microg) to screen for CR GNB and later were speciated and the antimicrobial susceptibilities were confirmed by standardized disc-diffusion tests . RESULTS: The mean prevalence of CR GNB colonization was 2.6% (range 0.9% to 5.3%) . The colonization frequency was higher in the last survey than it was in the first survey . CR GNB-colonized strains included Pseudomonas species (21%), but more than half were non-Pseudomonas enterics such as Acinetobacter baumannii (25%), Proteus mirabilis (17%), and Providencia stuartii (13%) . None of the patients who had colonization with CR GNB had subsequent infections with the same species . Patients with colonization had more exposure to ciprofloxacin and they were more likely to have been recently admitted from an acute-care hospital and have decubitus ulcers . During the study period, of 336 patients surveyed, 98 (29%) patients developed suspected infections and cultures were done; the infection rate was 4.7 per 1000 patient days . Of these infected patients, 59 (60%) were infected by GNBs; the infection rate was 2.3 per 1000 patient days . Nineteen percent of the GNB infections were treated with a quinolone . (Overall, quinolones constituted about 17% of antibiotic usage in the SNF) . Only 3 (5%) of the patients infected with GNB were infected with CR GNB, including Pseudomonas and Providenci a species . The CR GNB infections involved multiple sites, multiple organisms, and long length of stay in the SNF . CONCLUSIONS: The findings indicate that in this community SNF, a low frequency of colonization or infection with CR GNB existed . Whether continued moderate use of quinolones will lead to increasing levels of CR GNB will require further study. Am J Infect Control, 1998 Dec, 26(6), 544 - 51 Methicillin-resistant Staphylococcus aureus and Acinetobacter baumannii: an unexpected difference in epidemiologic behavior; Bernards AT et al.; BACKGROUND: The Dutch guideline on hospital policy for the prevention of nosocomial spread of methicillin-resistant Staphylococcus aureus (MRSA) states that patients transferred from hospitals abroad must be placed in strict isolation immediately on admission to a hospital in the Netherlands . Three patients colonized with both MRSA and a multiresistant Acinetobacter were transferred from hospitals in Mediterranean countries to 3 different hospitals in the Netherlands . Despite isolation precautions, Acinetobacter spread in 2 of the 3 hospitals, whereas nosocomial spread of MRSA did not occur . METHODS: For outbreak analysis, the Acinetobacter isolates, identified as Acinetobacter baumannii by the use of amplified ribosomal DNA restriction analysis, were comparatively typed by 4 methods . Comparison of isolation measures in the hospitals was performed retrospectively . RESULTS: In the 2 hospitals in which nosocomial spread of Acinetobacter occurred, most of the epidemiologically related isolates were indistinguishable from the index strains . In these 2 hospitals, isolation measures were in concordance with those recommended for the prevention of contact transmission . The precautions of the hospital in which no outbreak occurred included the prevention of airborne transmission . CONCLUSIONS: Precautions recommended for multiresistant gram-negative organisms are insufficient for the prevention of nosocomial spread of multiresistant Acinetobacter . The airborne mode of spread of acinetobacters should be taken into account, and guidelines should be revised accordingly. Rev Med Chil, 1998 Aug, 126(8), 978 - 80 {Priapism in a patient with chronic myeloid leukemia}; Rojas B et al.; Priapism is a rare complication of hematological diseases . Among leukemia, it is most frequently seen in patients with chronic myeloid leukemia, due to the high leukocyte counts that these patients achieve . We report a 22 years old male who presented with a priapism lasting more than 24 hours . Thirty six hours after admission and subsequent to a leukopheresis, penile relaxation was obtained . Despite good hematological response to therapy, an extensive penile and uretral necrosis, associated to an Acinetobacter infection, ensued between the fourth and fifth day of admission, that required surgical treatment. Clin Infect Dis, 1998 Nov, 27(5), 1286 - 90 Suppurative Acinetobacter baumanii thyroiditis with bacteremic pneumonia: case report and review; Yu EH et al.; Suppurative thyroiditis is rare, and the major pathogens are Staphylococcus and Streptococcus species . We present a case caused by Acinetobacter baumanii, which has never before been reported . We review another 191 cases from the English-language literature (1980 to April 1997) and make a comparison with a review of 224 cases (1900-1980) . As the numbers of immunocompromised patients increase, cases of suppurative thyroiditis are increasing . Pneumocystis carinii has become an important pathogen . Most patients (83.1%) with bacterial infections were euthyroid, whereas those with fungal or mycobacterial infections tended to be hypothyroid (62.5%) and hyperthyroid (50%), respectively. Antibiot Khimioter, 1998, 43(10), 19 - 23 {Selection of antibacterial therapy for treatment of infections in elderly patients}; Belousov IuB et al.; Examination of 60 elderly outpatients with lower respiratory tract infections (LRTI) revealed that 73 per cent of the patients isolated the pathogen associations and only 27 per cent isolated the monocultures . Grampositive cocci including Streptococcus pneumoniae were isolated from 70 per cent of the patients, Haemophilus influenzae and H.parainfluenzae were isolated from 20 per cent of the patients and Acinetobacter spp., Citrobacter spp., Enterobacter spp., Proteus spp . and Pseudomonas aeruginsa were isolated from 10 per cent of the patients . The patients were treated with ciprofloxacin, cefaclor or amoxycillin/clavulanic acid . Ciprofloxacin proved to be the most efficient agent . The regimens of the ofloxacin use in a dose of 400 mg orally once a day or in a dose of 200 mg intravenously twice a day for 2-4 days followed by the oral use for 6-8 days in the treatment of 24 patients with LRTI hospitalized into a therapeutic unit were compared . it was shown (pharmacokinetically as well) that the regiment with the drug use in the single dose was more efficient . Lomefloxacin was suggested to be the most advantageous drug in the treatment of elderly patients with LRTI because of its easy use, practically no dependence of the pharmacokinetics on the patient age and almost no nephrotoxic action. Diagn Microbiol Infect Dis, 1998 Oct, 32(2), 101 - 5 Antimicrobial activity of merocyanine 540: a photosensitizing dye; Dunne WM Jr et al.; The antimicrobial activity of merocyanine 540 (MC 540), a photosensitizing dye previously used to purge malignant cells from autologous bone marrow grafts, was evaluated against a panel of Gram-positive and Gram-negative bacteria and Candida albicans in the presence and absence of light . In the absence of light, MC 540 demonstrated no antibacterial activity against any of the organisms tested . When combined with increasing intervals of photoillumination, growth inhibition was observed with all Gram-positive organisms tested except Mycobacterium fortuitum . Photosensitizing growth inhibition was also observed with Moraxella catarrhalis but not with any other Gram-negative bacilli including members of the Enterobacteriaceae, Pseudomonas aeruginosa, Acinetobacter baumannii, Stenotrophomonas maltophila, or Burkhoderia cepacia . These results suggested that differences in cell wall structure confer resistance to the photodamaging effects of the dye . MC 540 exhibited no antimicrobial activity against C . albicans in the presence or absence of light. J Infect, 1998 Jan, 36(1), 5 - 15 Bacteriophages show promise as antimicrobial agents; Alisky J et al.; The emergence of antibiotic-resistant bacteria has prompted interest in alternatives to conventional drugs . One possible option is to use bacteriophages (phage) as antimicrobial agents . We have conducted a literature review of all Medline citations from 1966-1996 that dealt with the therapeutic use of phage . There were 27 papers from Poland, the Soviet Union, Britain and the U.S.A . The Polish and Soviets administered phage orally, topically or systemically to treat a wide variety of antibiotic-resistant pathogens in both adults and children . Infections included suppurative wound infections, gastroenteritis, sepsis, osteomyelitis, dermatitis, empyemas and pneumonia; pathogens included Staphylococcus, Streptococcus, Klebsiella, Escherichia, Proteus, Pseudomonas, Shigella and Salmonella spp . Overall, the Polish and Soviets reported success rates of 80-95% for phage therapy, with rare, reversible gastrointestinal or allergic side effects . However, efficacy of phage was determined almost exclusively by qualitative clinical assessment of patients, and details of dosages and clinical criteria were very sketchy . There were also six British reports describing controlled trials of phage in animal models (mice, guinea pigs and livestock), measuring survival rates and other objective criteria . All of the British studies raised phage against specific pathogens then used to create experimental infections . Demonstrable efficacy against Escherichia, Acinetobacter, Pseudomonas and Staphylococcus spp . was noted in these model systems . Two U.S . papers dealt with improving the bioavailability of phage . Phage is sequestered in the spleen and removed from circulation . This can be overcome by serial passage of phage through mice to isolate mutants that resist sequestration . In conclusion, bacteriophages may show promise for treating antibiotic resistant pathogens . To facilitate further progress, directions for future research are discussed and a directory of authors from the reviewed papers is provided. J Clin Microbiol, 1998 Dec, 36(12), 3674 - 9 Comparison of phenotypic and genotypic techniques for identification of unusual aerobic pathogenic gram-negative bacilli; Tang YW et al.; Rapid and accurate identification of bacterial pathogens is a fundamental goal of clinical microbiology, but one that is difficult or impossible for many slow-growing and fastidious organisms . We used identification systems based on cellular fatty acid profiles (Sherlock; MIDI, Inc., Newark, Del.), carbon source utilization (Microlog; Biolog, Inc., Hayward, Calif.), and 16S rRNA gene sequence (MicroSeq; Perkin-Elmer Applied Biosystems Division, Foster City, Calif.) to evaluate 72 unusual aerobic gram-negative bacilli isolated from clinical specimens at the Mayo Clinic . Compared to lengthy conventional methods, Sherlock, Microlog, and MicroSeq were able to identify 56 of 72 (77.8%), 63 of 72 (87.5%), and 70 of 72 (97.2%) isolates to the genus level (P = 0.002) and 44 to 65 (67.7%), 55 of 65 (84.6%), and 58 of 65 (89.2%) isolates to the species level (P = 0.005), respectively . Four Acinetobacter and three Bordetella isolates which could not be identified to the species level by conventional methods were identified by MicroSeq . In comparison to the full 16S rDNA sequences, the first 527 bp provided identical genus information for all 72 isolates and identical species information for 67 (93.1%) isolates . These data show that MicroSeq provides rapid, unambiguous identification of clinical bacterial isolates . The improved turnaround time provided by genotypic identification systems may translate into improved clinical outcomes. Scand J Infect Dis, 1998, 30(4), 421 - 3 Appearance of resistance to meropenem during the treatment of a patient with meningitis by Acinetobacter; Nunez ML et al.; A case is reported of a patient who developed Acinetobacter meningitis after an external ventricular drainage system had been fitted for control of intracranial pressure . During the process, nine strains of Acinetobacter isolated from her cerebrospinal fluid were indistinguishable by analysis of total genomic DNA by pulse-field gel electrophoresis . The first eight strains were sensitive to meropenem and imipenem (MICs < 1 g/l) . The MIC of the last one, which had been recovered after 32 days during two courses of treatment with meropenem, increased to > 32 g/l for meropenem, while with imipenem the increase was minimal (MIC = 1.5 g/l) . The microorganism persisted in the central nervous system despite the administration of different antimicrobials, including intraventricular aminoglycosides and six changes in the external ventricular system . The patient died 68 days after admission to the intensive care unit from bilateral cerebral ischemic lesions, intraventricular hemorrhage and cerebral edema with endocraneal hypertension, the Acinetobacter ventriculitis also contributing to this state. J Urol, 1998 Dec, 160(6 Pt 1), 2229 - 31 Polymerase chain reaction amplification of bacterial 16S rRNA genes from cold-cup biopsy forceps; Keay S et al.; PURPOSE: In looking for a possible infectious cause for interstitial cystitis (IC), we previously determined that bladder tissue specimens from both IC patients and controls were uniformly positive by polymerase chain reaction assay (PCR) for bacterial 16S ribosomal RNA genes from various genera including Escherichia, Propionobacterium, Acinetobacter, and Salmonella . We therefore determined whether the biopsy forceps might be contaminated with bacterial DNA . MATERIALS AND METHODS: A total of 23 samples were obtained following disinfection of 6 cold-cup bladder biopsy forceps (2 to 5 specimens from each forceps over a period of 19 months) . DNA was extracted from each sample, and PCR performed using nested primers from a highly conserved region of the bacterial 16S rRNA gene . Amplified DNA was purified and sequenced, and the sequences obtained were compared with bacterial rRNA gene sequences recorded in GenBank . RESULTS: Thirteen of 23 forceps specimens were positive by PCR for bacterial DNA, including at least one rinse from each of the 6 forceps . In comparison, none of 9 negative control specimens (sterile distilled water put into tubes and processed in the same manner as forceps rinses) had detectable bacterial DNA . Sequence data indicated the presence of a predominant organism in 12 of the 13 positive specimens, with >95% homology to DNA from several different genera of bacteria including Escherichia, Propionobacterium, Stenotrophomonas and Pseudomonas . CONCLUSIONS: These data indicate that reusable bladder biopsy forceps are frequently contaminated with bacterial DNA . Tissue specimens procured with such instruments therefore are inappropriate sources to look for the presence of bacterial pathogens by PCR. J Bacteriol, 1998 Nov, 180(22), 5822 - 7 Expression of alkane hydroxylase from Acinetobacter sp . Strain ADP1 is induced by a broad range of n-alkanes and requires the transcriptional activator AlkR; Ratajczak A et al.; In Acinetobacter sp . strain ADP1, alkane degradation depends on at least five essential genes . rubAB and xcpR are constitutively transcribed . Here we describe inducible transcription of alkM, which strictly depends on the presence of the transcriptional activator AlkR . alkR itself is expressed at a low level, while a chromosomally located alkM::lacZ fusion is inducible by middle-chain-length alkanes from heptane to undecane, which do not support growth of ADP1, and by long-chain-length alkanes from dodecane to octadecane, which are used as sources of carbon and energy . The putative AlkM substrate 1-dodecene is also an effective inducer . Products of alkane hydroxylase activity like 1-dodecanol prevent induction of alkM expression . alkM is expressed only in stationary phase, suggesting its dependence on at least one other regulatory mechanism. Zentralbl Bakteriol, 1995 Oct, 282(4), 372 - 83 Comparative classification of Acinetobacter baumannii strains using seven different typing methods; Seltmann G et al.; A group of 49 Acinetobacter baumannii strains obtained from several hospital outbreaks and some sporadic cases were typed by biotyping, antimicrobial susceptibility testing, pulsed-field gel electrophoresis (PFGE), plasmid typing, multilocus enzyme electrophoresis, whole-cell protein profile, and Fourier-transform infrared (FT-IR) spectroscopy . All these methods have shown a high degree of reproducibility and are capable of recognising strains from the same epidemiological event . However, their power to discriminate between epidemiologically unrelated strains varies, with PFGE being superior to the other methods investigated . FT-IR spectroscopy, which has not yet been used for typing of Acinetobacter strains, proved to be a very rapid and highly reproducible method, but was somewhat limited in its discriminating power. Zentralbl Bakteriol, 1998 Oct, 288(2), 175 - 80 Serotyping of clinical isolates of Acinetobacter baumannii and genospecies 13 capable of growth at 44 degrees C: detection of four new serovars; Traub WH; Four new serovars (sv 35-38) were detected among clinical isolates of Acinetobacter baumannii and the unnamed genospecies 13 capable of growth at 44 degrees C . Polyclonal rabbit antisera were serovar-specific . None of them cross-reacted with 34 previously recognized servars of A . baumannii and genospecies 13 nor with 26 serovars of genospecies 3. Rev Esp Cardiol, 1998 Sep, 51(9), 769 - 71 {Dehiscence of a composite aortic graft (Bono and Bentall technique) secondary to Acinetobacter endocarditis}; Alvarez J et al.; Acinetobacter sp . are gram-negative bacteria and usually resistant to multiple antibiotics . They are a customary cause of nosocomial infections, but are uncommon etiologic agents of endocarditis . We present a case of endocarditis caused by Acinetobacter iwoffi in a composite aortic graft with a St . Jude prosthetic valve, using the Bono and Bentall procedure, complicated with multiple graft dehiscenses causing first a peritube pseudoaneurysm and finally severe paraprosthetic valve regurgitation to the left ventricle which required emergency surgery. Res Microbiol, 1998 Sep, 149(8), 557 - 66 Characterization of oligonucleotide probes for the identification of Acinetobacter spp., A . baumannii and Acinetobacter genomic species 3; Lagatolla C et al.; The 16S-23S intergenic spacer regions of four Acinetobacter genomic species belonging to the A . calcoaceticus-A . baumannii (Acb) complex, i.e . genomic species 1 (A . calcoaceticus), genomic species 2 (A . baumannii), genomic species 3 and Tjernberg and Ursing (TU) genomic species 13, have been cloned and sequenced . Sequence analysis led to the discovery of a single copy of IIe and Ala tRNA genes within each spacer . Sequence comparison allowed the identification of a 192-base-pair long highly conserved sequence between the 3' end of the 16S rRNA and the 5' end of the tRNA(Ala) genes . Moreover, two short regions, which were specific to, respectively, genomic species 2 and 3, could be identified . Oligonucleotides corresponding to these sequences were constructed and tested for the ability to hybridize with chromosomal DNA extracted from Acinetobacter belonging to different genomic species and with chromosomal DNA of other bacterial genera . One of these oligonucleotides was demonstrated to be useful as a sensitive and specific probe for A . baumannii . A less sensitive probe for Acinetobacter genomic species 3 was also developed. Biol Chem, 1998 Aug-Sep, 379(8-9), 1207 - 11 PQQ as redox shuttle for quinoprotein glucose dehydrogenase; Jin W et al.; The role of pyrroloquinoline quinone (PQQ) as a redox shuttle between an electrode and the active site of soluble quinoprotein glucose dehydrogenase (sGDH) from Acinetobacter calcoaceticus has been investigated using both electrochemical and spectrophotometric methods . Reversible redox behavior of PQQ was observed at cystamine-modified gold electrodes . sGDH is able to reduce free PQQ, i.e . PQQ that is not bound to the enzyme and therefore could act as a mediator between the enzyme and the cystamine-modified electrode . The second order rate constants for the reduction of PQQ by sGDH are 6 x 10(3) M(-1) S(-1) and 64 M(-1) S(-1) in the absence and in the presence of calcium ions, respectively . Similarly, the interaction with a second redox protein is realized via the PQQ shuttle . Using DC voltammetry, the reduction rate of cytochrome c (cyt c) by PQQH2 was determined to be on the order of 10(4) M(-1) S(-1) Syst Appl Microbiol, 1998 Mar, 21(1), 33 - 9 Evaluation of amplified ribosomal DNA restriction analysis for identification of Acinetobacter genomic species; Dijkshoorn L et al.; Further to a previous study, the usefulness of amplified ribosomal DNA restriction analysis (ARDRA) for identification of Acinetobacter genomic species (DNA groups) was tested . A set of 202 Acinetobacter strains of 18 described genomic species and 17 unclassified strains were used . Restriction patterns obtained with a standard panel of restriction enzymes CfoI, AluI, MboI, RsaI and MspI allowed for separation of 11 DNA groups . With the additional use of restriction enzymes BfaI and BsmAI, five other (genomic) species could be differentiated, leaving only A . haemolyticus and DNA group 13BJ/14TU unseparated . With the standard panel of enzymes, ten new ARDRA profiles were noted in 14 unclassified strains . Two other unclassified strains had a profile in common with DNA group 15BJ, but were differentiated from this DNA group by restriction with bfaI . One remaining unclassified strain could not be differentiated from DNA group 17 by the standard panel of enzymes or by the enzymes BfaI and BsmAI . Results demonstrate the utility of ARDRA for identification of most genomic species of Acinetobacter . Furthermore, new ARDRA profiles that were shared by several unclassified strains may indicate so far undescribed genomic species in the genus. Gen Physiol Biophys, 1998 Jun, 17(2), 105 - 16 Binding modes of PCBs to a degrading enzyme: a receptor-mapping study; Hornak V et al.; The binding site of a PCB-degrading enzyme was mapped using the published data on biodegradation rates of individual PCB congeners by the Acinetobacter P6 strain . For this purpose an approach allowing for multiple binding modes of individual congeners, resulting from the symmetry of the biphenyl skeleton, was used . The effect of substitution patterns and conformational flexibility of individual congeners on their binding to a protein were investigated . The resulting map of the binding site is described by three parameters that indicate the importance of positions 4, 5', 5, 2' in a basic substitution pattern, the first two being favourable while the other two unfavourable for binding . An incorporation of conformational energy dependences of individual ligands into the model showed that ligand's conformation is either not a limiting factor for binding or that ligands bind in their relaxed conformations. J Hosp Infect, 1998 Sep, 40(1), 27 - 34 The prognostic factors of adult gram-negative bacillary meningitis; Lu CH et al.; Seventy-seven patients with Gram-negative bacillary meningitis (GNBM), 57 males and 20 females, aged 17-86 years, were identified at Kaohsiung Chang Gung Memorial Hospital, over an 11-year period . Fifty-four infections were community-acquired, and 23 were nosocomial; 49 were spontaneous and 28 occurred after head surgery or neurosurgery . The organisms most frequently involved were Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli, and Acinetobacter . Rarer pathogens included Citrobacter species, Serratia marcescens, Enterobacter cloacae, and Proteus mirabilis . All patients who did not receive appropriate antibiotic therapy died . The mortality in those treated with appropriate antibiotics was 28% . Other statistically significant prognostic factors included septic shock, initial level of consciousness, hyperosmolar hyperglycemic nonketotic coma, disseminated intravascular coagulation, high cerebrospinal fluid lactate levels and leucocytosis . In the multiple logistic regression analysis, only appropriate antimicrobial therapy and septic shock were strongly associated with mortality even after adjusting for other potentially confounding factors . Despite the high mortality, management can be improved by early diagnosis, early use of appropriate antibiotics, and correction of underlying and associated medical derangement. J Clin Microbiol, 1998 Nov, 36(11), 3415 - 6 In vitro activities of ampicillin-sulbactam and amoxicillin-clavulanic acid against Acinetobacter baumannii; Pandey A et al.; In vitro susceptibility patterns of newer beta-lactamase-inhibiting antibiotics ampicillin-sulbactam (A/S) and amoxicillin-clavulanic acid (A/C) for 100 consecutive isolates of Acinetobacter baumannii obtained from various clinical samples were studied . The A/C MIC for 86% of the strains was more than 16/8 microgram/ml, whereas there was an A/S MIC of more than 16/8 microgram/ml for only 38% of the strains . This showed that A/S has significantly superior in vitro activity compared to A/C against A . baumannii, although, theoretically, both should have similar activities . The therapeutic superiority of A/S over A/C needs to be studied, or else the breakpoints for these agents in in vitro tests need to be redefined. J Biol Chem, 1998 Oct 23, 273(43), 28122 - 31 Characterization of a novel branched tetrasaccharide of 3-deoxy-D-manno-oct-2-ulopyranosonic acid . The structure of the carbohydrate backbone of the lipopolysaccharide from Acinetobacter baumannii strain nctc 10303 (atcc 17904); Vinogradov EV et al.; For the first time, the tetrasaccharide Kdoalpha2-->5Kdoalpha2-->5(Kdoalpha2-->4)Kdo (Kdo is 3-deoxy-D-manno-oct-2-ulopyranosonic acid) has been identified in a bacterial lipopolysaccharide (LPS), i.e . in the core region of LPS from Acinetobacter baumannii NCTC 10303 . The LPS was analyzed using compositional analysis, mass spectrometry, and NMR spectroscopy . The disaccharide D-GlcpNbeta1-->6D-GlcpN, phosphorylated at O-1 and O-4', was identified as the carbohydrate backbone of the lipid A . The Kdo tetrasaccharide is attached to O-6' of this disaccharide and is further substituted by short L-rhamnoglycans of varying length and by the disaccharide D-GlcpNAcalpha1-->4D-GlcpNA (GlcpNA, 2-amino-2-deoxy-glucopyranosuronic acid) . The core region is not substituted by phosphate residues and represents a novel core type of bacterial LPS . The complete carbohydrate backbone of the LPS is shown in Structure I as follows: where Rha is rhamnose . Except were indicated, monosaccharides possess the D-configuration . Sugars marked with an asterisk are present in non-stoichiometric amounts. Pathol Biol (Paris), 1998 Apr, 46(4), 245 - 52 {Bacteria of the Acinetobacter genus}; Joly-Guillou ML; Bacteria of the Acinetobacter genus received little attention for many years because of their weak pathogenic potential and changing taxonomy . Since the introduction starting in the 1980s of an ever increasing number of antimicrobials, these organisms have demonstrated their ability to adapt . They are causing an increasing number of nosocomial infections, most notably in intensive care units . The selection pressure exerted by antimicrobials and the use of increasingly invasive diagnostic and therapeutic procedures are the main factors that promote emergence of Acinetobacter in high-risk patients . Acinetobacter exhibit a high level of resistance to antimicrobials and are capable of persisting in hostile environments (humidity or dryness, presence of some antiseptics) . As a result, they can cause nosocomial outbreaks . Identification of carriers and colonized patients, rigorous isolation, and scrupulous cleaning procedures are effective control measures . Despite these efforts, however, Acinetobacter baumannii now contributes a significant proportion of nosocomial infections. Pathol Biol (Paris), 1998 Jun, 46(6), 385 - 94 {An Acinetobacter baumanii outbreak at the Versailles Hospital Center}; Pina P et al.; A . baumannii is a multiresistant bacteria which is recognised as responsible for nosocomial infections and hospital outbreaks . The control of these outbreaks depends on the strain's typing and on the fight's policy against nosocomial infections . An outbreak of A . baumannii is occurred to patients who were hospitalized in Centre Hospitalier de Versailles . To investigate this outbreak, we have determined the biotype (Bouvet's method), the succeptibility pattern (disk diffusion and agar dilution results were analysed with the hierarchical classification and main component analysis) and the total DNA macrorestriction pattern (Pulse Field Gel Electrophoresis using SmaI restriction enzyme) . A risk factors for A . baumannii acquisition were delineated in case-control study . During 2 years, 38 patients have been infected or colonized to A . baumannii . Thirty two patients were hospitalized in ICU . We studied 38 non repetitive clinical isolates and 9 strains of the patient's rooms . Four biotypes were defined by the Bouvet's typing method . Fourteen groups were obtained when succeptibility results were analysed with the hierarchical classification and 6 with the main composant analysis . The molecular typing permit us to define 4 epidemic and 6 sporadic strains . All the epidemic strains were isolated on ICU hospitalized patients . Our study has shown wide contamination in patient's rooms (Water tap, dry surfaces, patient's mattresses...) . Environmental objects have been a major risk factor for A . baumannii acquisition . The control of this outbreak has been possible by application of hygienic measures (hands washing, isolment, meticulous cleaning of the ICU and environmental controls) . No new case is occurred in the last year . Typing methods and case-control study are necessary to investigate cross-infections and take efficient measures against these outbreaks. Pathol Biol (Paris), 1998 Jun, 46(6), 380 - 4 {Bacteria isolated from protected bronchopulmonary samples: variation as a function of the previous length of stay in the recovery room}; Bert F et al.; We retrospectively reviewed the variation of the organisms recovered from 403 protected bronchopulmonary specimens in three surgical intensive care units according to the time elapsed from admission . The predominant pathogens during the four first days were Haemophilus influenzae (33.3%), Staphylococcus aureus (18.2%), mostly methicillin susceptible strains, and Streptococcus pneumoniae (14.3%) . After the fourth day, they were progressively replaced by typical nosocomial bacteria such as methicillin resistant Staphylococcus aureus, Pseudomonas aeruginosa and Acinetobacter baumannii . For Pseudomonas aeruginosa and cephalosporinase-producing Enterobacteriaceae, strains resistant to third generation cephalosporins occurred significantly later than the susceptible strains . These results indicate that the time elapsed from intensive care unit admission has a major influence on the bacteriology of respiratory tract infections, but no clear cut-off point between early-onset and late onset pneumonia is evident. Res Microbiol, 1997 Dec, 148(9), 777 - 84 PCR-amplified 16S and 23S rDNA restriction analysis for the identification of Acinetobacter strains at the DNA group level; Garcia-Arata MI et al.; The genus Acinetobacter is phenotypically rather homogeneous, but genotypically heterogeneous . In this study, a simple method based on restriction analysis of a PCR-amplified large fragment (4.5 kb) of most of the ribosomal operon (16S and 23S ribosomal genes and the spacer in-between) was investigated . Sixty-seven collection strains belonging to the 20 DNA groups proposed until 1993 were studied . Using the enzyme Sau3AI, 25 DNA profiles were obtained . Strains belonging to DNA groups 1, 3, 6, TU13 and TU15 showed two profiles each, and DNA groups 4, 5 and 7 showed profiles with variants showing less intensive additional bands . The remaining 12 groups showed 12 different profiles . The profiles obtained were DNA-group-specific except for one profile which was shared between the unnamed DNA group 3 and a rarely encountered genotypically related DNA group . These two DNA groups could be separated by using the enzyme Hinf1 . Twenty-five additional clinical isolates previously characterized by standard DNA-DNA hybridization were selected in a double-blind fashion for identification at the DNA group level to check the reliability of the assay . All strains were correctly identified at the DNA group level . PCR-amplified 16S and 23S rDNA restriction analysis is both an accurate and rapid method for the identification of Acinetobacter at the DNA group level. Res Microbiol, 1997 Mar-Apr, 148(3), 237 - 49 Molecular characterization of an n-alkane-degrading bacterial community and identification of a new species, Acinetobacter venetianus; Di Cello F et al.; Twenty-five bacterial strains isolated from the Venice lagoon and implicated in the degradation of n-alkanes, n-alkanols, n-alkanals and n-alkanoates were characterized in molecular and physiological terms . The isolates were grouped by amplified ribosomal DNA restriction analysis (ARDRA) into seven clusters, corresponding to seven species, six of which were identified on the basis of 16S rDNA sequencing . Genetic variability among strains was shown by random amplified polymorphic DNA (RAPD) . Only strains of the new species Acinetobacter venetianus grew with n-alkanes (C10, C14 and C20) and their respective oxidation products as sole carbon sources . Strains of the other three species identified thrived on n-alkane oxidation products (n-alkanols, n-alkanals, n-alkanoates) . The other three species were not able to grow on any of the substrates tested . Analysis of plasmid content showed that only A . venetianus strains harboured plasmids . These plasmids contained sequences homologous to the Pseudomonas oleovorans alkBFGH genes. Eur J Clin Microbiol Infect Dis, 1998 Jun, 17(6), 377 - 84 Bacteraemia in the adult intensive care unit of a teaching hospital in Nottingham, UK, 1985-1996; Crowe M et al.; Bacteraemia is an important cause of morbidity and mortality in the intensive care unit . In this study the distribution of organisms causing bacteraemic episodes in patients in the adult intensive care unit of a large teaching hospital was determined . Particular emphasis was placed on the type of organisms isolated from community- and hospital-acquired bacteraemia, the suspected source of infection, the possible risk factors associated with bacteraemia, and outcome . The incidence of bacteraemia and fungaemia increased from 17.7 per 1000 admissions in 1985 to 80.3 in 1996 . A total of 315 episodes of bacteraemia and fungaemia were documented over a 12-year period, of which 18% were considered community-acquired and 82% hospital-acquired . Gram-positive and gram-negative bacteria accounted for 46.9% and 31.5% of the episodes, respectively . Polymicrobial infection accounted for 17.8% and fungi for 3.8% of the episodes . Staphylococcus aureus (22.5%), Staphylococcus epidermidis (7.6%), and Streptococcus pneumoniae (7.9%) were the predominant gram-positive bacteria implicated, whereas Escherichia coli (6%), Enterobacter cloacae (7%), Klebsiella aerogenes (3.8%), Pseudomonas aeruginosa (5.1%), and Acinetobacter spp . (3.8%) were the predominant gram-negative bacteria isolated . The two most common sources of infection were the respiratory tract (39.7%) and an intravascular line (24.5%), but in 8.9% of episodes the focus of infection remained unknown . Bacteraemic patients stayed in the unit for a longer period (12 days) than did non-bacteraemic patients (3 days) . The overall mortality related to bacteraemia and candidaemia was 44.4% . Surveillance of bacteraemia in the intensive care unit is important in detecting major changes in aetiology, e.g., the increasing incidence of gram-positive bacteraemia, the emergence of methicillin-resistant Staphylococcus aureus in 1995, and the emergence of Enterobacter cloacae . It is of value in determining empirical antimicrobial therapy to treat presumed infection pending a microbiological diagnosis and in directing the development of guidelines for infection prevention, e.g., guidelines for central venous catheter care. Antimicrob Agents Chemother, 1998 Oct, 42(10), 2759 - 61 Characterization of IS18, an element capable of activating the silent aac(6')-Ij gene of Acinetobacter sp . 13 strain BM2716 by transposition; Rudant E et al.; Insertion sequence IS18 was detected by analysis of the spontaneous aminoglycoside resistant mutant Acinetobacter sp . 13 strain BM2716-1 . Insertion of the element upstream from the silent acetyltransferase gene aac(6')-Ij created a hybrid promoter that putatively accounts for the expression of the aminoglycoside resistance gene . The 1, 074-bp IS18 element contained partially matched (20 out of 26 bases) terminal inverted repeats, one of which overlapped the 3' end of a 935-bp open reading frame potentially encoding a protein related to the transposases of the IS30 family . IS18 was found in 6 out of 29 strains of Acinetobacter sp . 13 but not in 10 strains each of A . baumannii and A . haemolyticus. J Bacteriol, 1998 Oct, 180(19), 5058 - 69 Mutation analysis of PobR and PcaU, closely related transcriptional activators in acinetobacter; Kok RG et al.; Acinetobacter PobR and PcaU are transcriptional activators that closely resemble each other in primary structure, DNA-binding sites, metabolic modulators, and physiological function . PobR responds to the inducer-metabolite p-hydroxybenzoate and activates transcription of pobA, the structural gene for the enzyme that converts p-hydroxybenzoate to protocatechuate . This compound, differing from p-hydroxybenzoate only in that it contains an additional oxygen atom, binds to PcaU and thereby specifically activates transcription of the full set of genes for protocatechuate catabolism . Particular experimental attention has been paid to PobR and PcaU from Acinetobacter strain ADP1, which exhibits exceptional competence for natural transformation . This trait allowed selection of mutant strains in which pobR function had been impaired by nucleotide substitutions introduced by PCR replication errors . Contrary to expectation, the spectrum of amino acids whose substitution led to loss of function in PobR shows no marked similarity to the spectrum of amino acids conserved by the demand for continued function during evolutionary divergence of PobR, PcaU, and related proteins . Surface plasmon resonance was used to determine the ability of mutant PobR proteins to bind to DNA in the pobA-pobR intergenic region . Deleterious mutations that strongly affect DNA binding all cluster in and around the PobR region that contains a helix-turn-helix motif, whereas mutations causing defects in the central portion of the PobR primary sequence do not seem to have a significant effect on operator binding . PCR-generated mutations allowing PobR to mimic PcaU function invariably caused a T57A amino acid substitution, making the helix-turn-helix sequence of PobR more like that of PcaU . The mutant PobR depended on p-hydroxybenzoate for its activity, but this dependence could be relieved by any of six amino acid substitutions in the center of the PobR primary sequence . Independent mutations allowing PcaU to mimic PobR activity were shown to be G222V amino acid substitutions in the C terminus of the 274-residue protein . Together, the analyses suggest that PobR and PcaU possess a linear domain structure similar to that of LysR transcriptional activators which largely differ in primary structure. Zhonghua Min Guo Wei Sheng Wu Ji Mian Yi Xue Za Zhi, 1994 Aug, 27(3), 133 - 9 {Assessment of a new four-hour diagnostic kit--RapID onE system for the identification of enteric bacteria}; Lee JH et al.; RapID onE System is a newly developed four-hour rapid diagnostic kit for the identification of enteric bacteria . To know the effectiveness of this system, we used 125 strains of oxidase-negative, gram-negative bacilli for this evaluation . Except for Acinetobacter calcoaceticus, all the bacilli belong to family Enterobacteriaceae . The bacterial strains of this assessment belong to 12 genera and 20 species . Among them, 84 strains were freshly isolated from clinical specimens and 41 strains were frozen (-70 degrees C) stock clinical isolates . The results show that 115 (92.0%) strains were correctly identifed to the species level . It yielded 92.9% and 90.2% of correct identification of fresh isolates and frozen stocks, respectively . In this paper, the reading criteria of RapID onE System would also be discussed. Klin Padiatr, 1998 Jul-Aug, 210(4), 256 - 60 {Bacteremic episodes in pediatric oncologic patients, especially caused by the Streptococcus viridans group}; Berner R et al.; BACKGROUND: The management of infectious complications plays a major role in the care for pediatric cancer patients . The majority of infections in the neutropenic patient present as fever of unknown origin without recovering a pathogen from the blood stream . The careful evaluation of bacteremic episodes is essential, since knowledge of the bacterial spectrum expected is crucial for the successful anti-infective treatment . PATIENTS AND METHODS: From 1985 to 1995 all bacteremic episodes in pediatric oncology patients at the University Children's Hospital Freiburg were retrospectively analyzed with respect to the pathogens encountered, the antibiotic susceptibility profile and the underlying conditions . RESULTS: Overall, 113 bacteremic episodes were encountered in pediatric oncology patients, 68 of them in patients with hematological malignancies, and 45 in patients with solid tumors . In both patient groups, gram-positive bacteria were predominant with 72% and 58%, respectively . In patients with hematological malignancies, viridans streptococci were the most frequently isolated pathogens (35%) with a relevant morbidity (29% of patients developed a severe sepsis syndrome and/or ARDS), but were found only in 9% of patients with solid tumors . In 28% of patients with leukemia or lymphoma, gram-negative rods were cultured, in 6% Pseudomonas spec., in 4% Acinetobacter spec., and in 18% enterobacteria . In patients with solid tumors, in 38% gram-negative rods were isolated, 7% Pseudomonas spec., 16% Acinetobacter spec., 16% enterobacteria . In 3 patients, fungemia was observed . The antibiotic susceptibility profile was quite favorable in both, gram-positive and -negative bacteria: none of the gram-positive isolates was resistant to vancomycin, none of the Staphylococcus aureus isolates was resistant to oxacillin . All gram-negative bacteria were fully susceptible to ceftazidime, imipenem and ciprofloxacin . CONCLUSION: Gram-positive bacteria account for 2/3 of all bacteremic episodes in pediatric oncology patients . Streptococcus viridans was the most important pathogen in hematological malignancies accounting for a significant, pathogen-specific morbidity. FEMS Microbiol Lett, 1998 Aug 15, 165(2), 357 - 62 Comparison of ARDRA and recA-RFLP analysis for genomic species identification of Acinetobacter spp; Jawad A et al.; The genus Acinetobacter is subdivided into genospecies on the basis of DNA relatedness of strains . Phenotypic tests are insufficient to identify the genospecies to which an isolate belongs . The effectiveness of two previously described PCR-based methods for genospeciating Acinetobacter spp . was compared using a group of 32 well-characterised strains representing six genospecies . Amplified ribosomal DNA restriction analysis (ARDRA) correctly identified all 32 strains . Using restriction fragment length polymorphism (RFLP) of recA PCR amplimers, only six of the 32 strains were correctly identified . Heterogeneity in the recA gene sequence was demonstrated within five of the genospecies . ARDRA proved to be a reliable method whereas analysis of recA RFLP profiles did not enable the genospecies of most of the isolates of Acinetobacter spp . to be determined. Southeast Asian J Trop Med Public Health, 1998 Mar, 29(1), 96 - 9 Bacterial pathogens (non-Mycobacterium) from sputum culture and antimicrobial susceptibility; Srifuengfung S et al.; Sputum culture of patients at Siriraj Hospital, Bangkok was 49.84% positive for bacterial pathogens in 1994 and 40.95% in 1995 . The average incidence of gram-negative rods was 3.11 fold more than the combination of gram-positive cocci and gram-negative cocci . The most common gram-negative rod was Pseudomonas aeruginosa, followed by either Klebsiella pneumoniae or Acinetobacter anitratus depending on year . The most common coccus was Staphylococcus aureus . From both years, the number of Haemophilus influenzae, Streptococcus pneumoniae, Burkholderia pseudomallei and Nocardia spp isolated were 122, 93, 13 and 11 strains respectively . For antimicrobial susceptibility, P . aeruginosa was sensitive to ceftazidime, imipenem, gentamicin, amikacin, netilmicin, ciprofloxacin (range 56-89%) . S . aureus (MSSA) was sensitive to common used drugs . S . aureus (MRSA) was sensitive to co-trimoxazole, fosfomycin, vancomycin (range 57-100%) and resistant to most drugs. JPEN J Parenter Enteral Nutr, 1998 Sep-Oct, 22(5), 291 - 6 Total nutrient admixtures appear safer than lipid emulsion alone as regards microbial contamination: growth properties of microbial pathogens at room temperature; Didier ME et al.; BACKGROUND: The extraordinary growth properties of most microorganisms in 10% and 20% lipid emulsions has led to the Centers for Disease Control and Prevention recommendation that if lipids are given through an i.v . line, the administration set should be replaced every 24 hours rather than the usual 72-hour interval used for crystalloid solutions, including those used for conventional total parenteral nutrition . For nearly 15 years, parenteral alimentation has been given as a total nutrient admixture (TNA), with the glucose, amino acids, and lipid mixed within the same bag and infused continuously over 24 hours . METHODS: We prospectively studied in a representative TNA (17.6% glucose, 5% amino acids, 4% lipid; pH 5.6, osmolality 1778) and in a control solution, 5% dextrose-in-water (D5%/W), the growth properties at 4, 25, and 35 degrees C of three isolates each of Staphylococcus epidermidis, Staphylococcus aureus, Enterobacter cloacae, Klebsiella oxytoca, Serratia marcescens, Acinetobacter calcoaceticus, Stenotrophomonas maltophilia, Pseudomonas aeruginosa, Burkholderia cepacia, Flavobacterium spp, and Candida albicans, and two isolates of Staphylococcus saprophyticus, the species that are most likely to contaminate TNA during preparation or administration and that have been implicated in >95% of all outbreaks and sporadic cases of nosocomial bloodstream infections traced to contaminated parenteral admixtures reported in the world literature . RESULTS: Growth in TNA at 25 and 35 degrees C occurred with only two species, C . albicans and S . saprophyticus, and only after 24 to 48 hours; D5%/W allowed growth at 25 degrees C of two gram-negative species, S . marcescens and B . cepacia . CONCLUSIONS: We conclude that TNA is a poor growth medium for most nosocomial pathogens and is no better than D5%/W . The need to replace administration sets every 24 hours with TNA should be reconsidered and ideally be studied in a prospective randomized trial. J Antimicrob Chemother, 1998 Aug, 42(2), 161 - 9 Comparison of the modified Stokes' method of susceptibility testing with results obtained using MIC methods and British Society of Antimicrobial Chemotherapy breakpoints; Gosden PE et al.; The majority of clinical microbiology laboratories in the UK use comparative disc diffusion methods based on the Stokes' method to determine antibiotic susceptibility . The technical validity of the results obtained from the modified Stokes' method of disc testing and how they relate to MIC data are not known . We studied susceptibility testing using a modified Stokes' disc diffusion method for a wide range of clinical isolates against which MICs had been determined by collaborators not involved with the disc testing evaluation . Results indicated that for 1301 organism-antibiotic combinations the number of major errors (where resistant strains were reported as sensitive) was 21/468 (4.4%) and the number of minor errors (where sensitive strains were reported as resistant) was 14/713 (1.9%) using ciprofloxacin breakpoints of 0.5 and 2 mg/L . There was good correlation between the disc susceptibility test and the MIC for 119 isolates of Enterobacteriaceae tested with the exception of Serratia spp . Excluding Serratia spp . the number of major errors for Enterobacteriaceae was 1/200 (0.5%) . Data revealed 2/25 (8%) major errors for Pseudomonas aeruginosa and 1/45 (2.2%) for Acinetobacter spp . Haemophilus influenzae showed a number of unexpected categorization errors . The modified Stokes' method performed accurately for Staphylococcus aureus and coagulase-negative staphylococci when tested for susceptibility to gentamicin, erythromycin, teicoplanin and vancomycin . No major errors were reported for Streptococcus pneumoniae and beta-haemolytic streptococci . Problems occurred with the detection of antibiotic resistance in Enterococcus spp . Major errors were seen for ampicillin (2/12 strains), teicoplanin (5/6 strains) and vancomycin (5/13 strains) using a 30 microg disc but only 1/13 strains using a 5 microg disc . Overall, from our data, the modified Stokes' disc diffusion antibiotic susceptibility test showed an unacceptable number of major errors but an acceptable number of minor errors. Appl Environ Microbiol, 1998 Sep, 64(9), 3499 - 502 Antibiotic resistance in Acinetobacter spp . isolated from sewers receiving waste effluent from a hospital and a pharmaceutical plant; Guardabassi L et al.; The possible increase of antibiotic-resistant bacteria in sewage associated with the discharge of wastewater from a hospital and a pharmaceutical plant was investigated by using Acinetobacter species as environmental bacterial indicators . The level of susceptibility to six antimicrobial agents was determined in 385 Acinetobacter strains isolated from samples collected upstream and downstream from the discharge points of the hospital and the pharmaceutical plant . Results indicated that while the hospital waste effluent affected only the prevalence of oxytetracycline resistance, the discharge of wastewater from the pharmaceutical plant was associated with an increase in the prevalence of both single- and multiple-antibiotic resistance among Acinetobacter species in the sewers. Appl Environ Microbiol, 1998 Sep, 64(9), 3290 - 9 Substrate specificity of and product formation by muconate cycloisomerases: an analysis of wild-type enzymes and engineered variants; Vollmer MD et al.; Muconate cycloisomerases play a crucial role in the bacterial degradation of aromatic compounds by converting cis,cis-muconate, the product of catechol ring cleavage, to (4S)-muconolactone . Chloromuconate cycloisomerases catalyze both the corresponding reaction and a dehalogenation reaction in the transformation of chloroaromatic compounds . This study reports the first thorough examination of the substrate specificity of the muconate cycloisomerases from Pseudomonas putida PRS2000 and Acinetobacter "calcoaceticus" ADP1 . We show that they transform, in addition to cis,cis-muconate, 3-fluoro-, 2-methyl-, and 3-methyl-cis, cis-muconate with high specificity constants but not 2-fluoro-, 2-chloro-, 3-chloro-, or 2,4-dichloro-cis,cis-muconate . Based on known three-dimensional structures, variants of P . putida muconate cycloisomerase were constructed by site-directed mutagenesis to contain amino acids found in equivalent positions in chloromuconate cycloisomerases . Some of the variants had significantly increased specificity constants for 3-chloro- or 2,4-dichloromuconate (e.g., A271S and I54V showed 27- and 22-fold increases, respectively, for the former substrate) . These kinetic improvements were not accompanied by a change from protoanemonin to cis,cis-dienelactone as the product of 3-chloro-cis,cis-muconate conversion . The rate of 2-chloro-cis,cis-muconate turnover was not significantly improved, nor was this compound dehalogenated to any significant extent . However, the direction of 2-chloro-cis,cis-muconate cycloisomerization could be influenced by amino acid exchange . While the wild-type enzyme discriminated only slightly between the two possible cycloisomerization directions, some of the enzyme variants showed a strong preference for either (+)-2-chloro- or (+)-5-chloromuconolactone formation . These results show that the different catalytic characteristics of muconate and chloromuconate cycloisomerases are due to a number of features that can be changed independently of each other. Pediatr Infect Dis J, 1998 Aug, 17(8), 716 - 22 Outbreak of Acinetobacter spp . bloodstream infections in a nursery associated with contaminated aerosols and air conditioners; McDonald LC et al.; BACKGROUND: Acinetobacter spp . are multidrug-resistant bacteria that grow well in water and cause infections with unexplained, increased summer prevalence . In August, 1996, eight infants acquired Acinetobacter spp . bloodstream infection (A-BSI) while in a nursery in the Bahamas; three infants died and an investigation was initiated . METHODS: A case patient was defined as any newborn in the nursery during August 6 to 13, 1996, with A-BSI . To identify risk factors for A-BSI we conducted a retrospective cohort study and performed environmental cultures and air sampling using settle plates . The genetic relatedness of environmental isolates was assessed by pulsed field gel electrophoresis . RESULTS: Of 33 patients in the nursery 8 (24%) met the case definition . Patients with peripheral iv catheters were more likely to develop A-BSI (8 of 21 vs . O of 10, P < 0.05) . Multivariate analysis among patients with iv catheters indicated that only exposure to one nurse was an independent risk factor for developing A-BSI (P < 0.005) . Nursery settle plates were more likely to grow Acinetobacter spp . than were settle plates from other hospital areas (8 of 9 vs . 0 of 5, P < 0.005); cultures from nursery air conditioners also grew Acinetobacter spp . Environmental isolates were genetically diverse . After installation of a new air conditioner in May, 1995, A-BSIs occurred more frequently during months of increased absolute humidity or environmental dew point . CONCLUSIONS: Acinetobacter spp . may cause nosocomial BSI and death among infants during periods of polyclonal airborne dissemination; breaks in aseptic technique during i.v . medication administration may facilitate transmission from the environment to the patient . Environmental conditions that increase air conditioner condensate may predispose to airborne dissemination via contaminated aerosols and increase the risk of nosocomial A-BSI. J Bacteriol, 1998 Sep, 180(17), 4466 - 74 Similarities between the antABC-encoded anthranilate dioxygenase and the benABC-encoded benzoate dioxygenase of Acinetobacter sp . strain ADP1; Bundy BM et al.; Acinetobacter sp . strain ADP1 can use benzoate or anthranilate as a sole carbon source . These structurally similar compounds are independently converted to catechol, allowing further degradation to proceed via the beta-ketoadipate pathway . In this study, the first step in anthranilate catabolism was characterized . A mutant unable to grow on anthranilate, ACN26, was selected . The sequence of a wild-type DNA fragment that restored growth revealed the antABC genes, encoding 54-, 19-, and 39-kDa proteins, respectively . The deduced AntABC sequences were homologous to those of class IB multicomponent aromatic ring-dihydroxylating enzymes, including the dioxygenase that initiates benzoate catabolism . Expression of antABC in Escherichia coli, a bacterium that normally does not degrade anthranilate, enabled the conversion of anthranilate to catechol . Unlike benzoate dioxygenase (BenABC), anthranilate dioxygenase (AntABC) catalyzed catechol formation without requiring a dehydrogenase . In Acinetobacter mutants, benC substituted for antC during growth on anthranilate, suggesting relatively broad substrate specificity of the BenC reductase, which transfers electrons from NADH to the terminal oxygenase . In contrast, the benAB genes did not substitute for antAB . An antA point mutation in ACN26 prevented anthranilate degradation, and this mutation was independent of a mucK mutation in the same strain that prevented exogenous muconate degradation . Anthranilate induced expression of antA, although no associated transcriptional regulators were identified . Disruption of three open reading frames in the immediate vicinity of antABC did not prevent the use of anthranilate as a sole carbon source . The antABC genes were mapped on the ADP1 chromosome and were not linked to the two known supraoperonic gene clusters involved in aromatic compound degradation. J Chemother, 1998 Aug, 10(4), 320 - 5 Bacteremia due to multiresistant gram-negative bacilli in neutropenic cancer patients: a case controlled study; Krcmery V Jr et al.; The aim of this study was to see if multiresistant Gram-negative bacteremias (MRGNB) are associated with specific risk factors and/or higher mortality in comparison to sensitive GNB (SGNB) . Both groups, 51 patients and 102 controls, were matched for sex, age, underlying disease and neutropenia . In addition there were no significant differences in the incidence of cytotoxic chemotherapy administered, vascular catheter insertion and catheter as source of bacteremia and etiology of bacteremia . The proportion of Klebsiella-Enterobacter, Pseudomonas aeruginosa, Acinetobacter spp . and Stenotrophomonas maltophilia was similar in both groups . Prior surgery (21.6% vs 7.6%, p<0.02) was significantly associated with SGNB . Previous prophylaxis with quinolones (45.1% vs 24.5%, p<0.045), and prior therapy with broad spectrum antibiotics (41.2% vs 27.5%, p<0.05) were significantly more frequently observed among patients than controls . Patients with bacteremia due to MRGNB were also significantly more frequently infected with resistant bacteria . Attributable mortality was similar (15.7% vs 13.75%, NS) in both groups, however cure rates were lower among MRGNB patients . Crude mortality was higher among patients (35.3% vs 13.75%, p<0.01) in comparison to controls . In conclusion, prior antimicrobial prophylaxis and therapy with several classes of antimicrobials represents a significant risk for development of resistance . Mortality due to multiresistant Gram-negative bacteremias was higher in comparison to bacteremias due to susceptible organisms. Microbiology, 1998 Aug, 144 ( Pt 8), 2085 - 93 rRNA-targeted fluorescent in situ hybridization analysis of bacterial community structure in river water; Kenzaka T et al.; An improved in situ hybridization technique, HNPP-FISH, using 2-hydroxy-3-naphthoic acid 2'-phenylanilide phosphate (HNPP) and Fast Red TR was applied to analyse the community structure of planktonic bacteria in river water . Oligonucleotide probes specific for the domain Bacteria (EUB338) and five bacterial groups {Flavobacterium-Cytophaga; Burkholderia-Pseudomonas (rRNA III)-authentic Alcaligenes; Vibrio-Aeromonas; Pseudomonas (rRNA I): the genus Acinetobacter} were used to investigate the bacterial community structure at two sites differing in organic carbon pollution level . At the eutrophic site, 54-68% of all cells visualized by staining with DAPI (4',6-diamidino-2-phenylindole) could be detected with probe EUB338 . In samples from the oligotrophic site, 39-45% of the total cells hybridized with EUB338 . At the eutrophic site, approximately 50% of the total cells were identified with the five group-specific probes; the bacterial community structure was dominated by the Flavobacterium-Cytophaga group and Burkholderia-Pseudomonas (rRNA III)-authentic Alcaligenes group . At the oligotrophic site, only 26-38% of the total cells were identified with the five group-specific probes . The community structure at the oligotrophic site was similar to that at the eutrophic site, although the percentage of EUB338-detectable cells differed . No appreciable change was found in the community structure during the sampling period at either site . The improved HNPP-FISH technique should be a useful tool for the analysis of microbial community composition. J Appl Microbiol, 1998 Jun, 84(6), 1069 - 84 Microbial communities of printing paper machines; Vaisanen OM et al.; The microbial content of printing paper machines, running at a temperature of 45-50 degrees C and at pH 4.5-5, was studied . Bacteria were prevalent colonizers of the machine wet end and the raw materials . A total of 390 strains of aerobic bacteria were isolated and 86% of these were identified to genus and species by biochemical, chemotaxonomic and phylogenetic methods . The most common bacteria found at the machine wet end were Bacillus coagulans and other Bacillus species, Burkholderia cepacia, Ralstonia pickettii, and in pink slimes, accumulating in the wire area and press section, species of Deinococcus, aureobacterium and Brevibacterium . Paper-making chemicals also contained species of Aureobacterium, B . cereus, B . licheniformis, B . sphaericus, Bordetella, Hydrogenophaga, Klebsiella pneumoniae, Pantoea agglomerans, Pseudomonas stutzeri, Staphylococcus and sometimes other enteric bacteria, but these did not colonize the process water . Yeasts and moulds were not present in significant numbers . A total of 131 strains were tested for their potential to degrade paper-making raw materials; 91 strains were found to have degradative activity, mainly species of Burkholderia and Ralstonia, Sphingomonas and Bacillus, and enterobacteria produced enzymes which degraded paper-making chemicals . Stainless steel adhering strains occurred in slimes and wire water and were identified as Burkholderia cepacia, B . coagulans and Deinococcus geothermalis . Coloured slimes were formed on the machine by species of Deinococcus, Acinetobacter and Methylobacterium (pink), Aureobacterium, Pantoea and Ralstonia (yellowish) and Microbulbifer-related strains (brown) . The impact of the strains and species found in the printing paper machine community on the technical quality of paper, machine operation, and as a potential biohazard (Hazard Group 2 bacteria), is discussed. Clin Infect Dis, 1998 Aug, 27 Suppl 1, S117 - 24 Clinical problems posed by multiresistant nonfermenting gram-negative pathogens; Quinn JP; In this review I will briefly survey the role of Pseudomonas aeruginosa, Acinetobacter baumanii, Stenotrophomonas maltophilia, and Burkholderia cepacia as opportunistic pathogens . A common feature of these organisms is intrinsic resistance to multiple antibiotics . All of these organisms can be recovered from the environment, commonly cause device-related infections, are often resistant to disinfectants, and have the potential to spread from patient to patient via fomites or the hands of medical personnel . Newer clinical syndromes will be emphasized, including the increasing importance of P . aeruginosa infections in patients with AIDS, as well as the role of carbapenems in selecting for A . baumanii and S . maltophilia and the unique niche of B . cepacia in patients with cystic fibrosis. Clin Infect Dis, 1998 Aug, 27 Suppl 1, S93 - 9 Resistance mechanisms in Pseudomonas aeruginosa and other nonfermentative gram-negative bacteria; Hancock RE; Nonfermentative gram-negative bacilli are still a major concern in compromised individuals . By far the most important of these organisms is Pseudomonas aeruginosa, although Acinetobacter baumannii (previously Acinetobacter calcoaceticus), Stenotrophomonas maltophilia (previously Pseudomonas and Xanthomonas maltophilia), and Burkholderia cepacia (previously Pseudomonas cepacia) are also of substantative concern because of their similar high intrinsic resistances to antibiotics . The basis for the high intrinsic resistance of these organisms is the lower outer-membrane permeability of these species, coupled with secondary resistance mechanisms such as an inducible cephalosporinase or antibiotic efflux pumps, which take advantage of low outer-membrane permeability . Even a small change in antibiotic susceptibility of these organisms can result in an increase in the MIC of a drug to a level that is greater than the clinically achievable level . In this review, the major mechanisms of resistance observed in the laboratory and clinic are summarized. J Food Prot, 1998 Jun, 61(6), 700 - 3 Bacterial populations associated with the dirty area of a South African poultry abattoir; Geornaras I et al.; Bacterial populations associated with three sample types from the neck region of poultry carcasses in the dirty area of an abattoir were characterized . Sample types before and after scalding were skin only, feathers only, and a skin and feather combination . The neck skin of carcasses after the defeathering processing stage was also sampled . Bacterial populations associated with water from the scald tank, rubber fingers at the exit of the defeathering machine, and air in the dirty area were also characterized . Bacterial colonies (751) were randomly isolated from yeast extract-supplemented tryptone soya agar plates exhibiting 30 to 300 colonies . Micrococcus spp . were isolated in the highest proportion from pre-and postscalded carcass samples (63.5 to 86.1% of isolates), regardless of the sample type . Conversely, Enterobacteriaceae (40.3%), Acinetobacter (19.4%), and Aeromonas/Vibrio (12.5%) species predominated on neck skin samples taken from mechanically defeathered carcasses . Isolates from the rubber fingers were, however, predominantly Micrococcus spp . (94.4%) . Bacterial groups isolated in the highest proportion from scald tank water samples were Micrococcus spp . (38.3%), species of Enterobacteriaceae (29.1%), and lactic acid bacteria (17.0%) . Corynebacterium spp., species of Enterobacteriaceae, and Micrococcus spp . were dominant on air settle plates. Indian Pediatr, 1998 Jan, 35(1), 27 - 32 Acinetobacter sepsis in newborns; Mishra A et al.; OBJECTIVE: To evaluate the clinico-epidemiological profile of Acinetobacter sepsis in neonates . DESIGN: Retrospective study . SETTING: Level II Neonatal Care Unit . SUBJECTS: 79 neonates with blood culture positive for Acinetobacter . METHODS: Relevant information was collected on a predesigned proforma from the case records and analyzed for clinical and epidemiological characteristics . RESULTS: The incidence of Acinetobacter septicemia was 11.1/1000 live births . Fifty-five babies were hospital born, 24 were outborn . Out of these, 64.6% babies were born at term and 40.5% had a birth weight of 2500 g or more . A cluster of 53 cases was seen between May and September 1995 . In cases with early onset sepsis (onset < 7 days of postnatal age), difficulty in breathing (n = 54), chest retraction (n = 35) and refusal to feed (n = 46) were seen more commonly as compared to late onset sepsis (p < 0.05) . Complications observed included meningitis, bleeding manifestations and necrotising enterocolitis in three, six and five babies, respectively . The organism was sensitive to ciprofloxacin (96.2%), amikacin (92.4%) and gentamicin (87.3%) . A response rate of 52.4% was observed with Ciprofloxacin in babies not responding to cefotaxime and amikacin combination . The overall mortality was 13.9% . CONCLUSION: Nosocomial Acinetobacter sepsis may affect fullterm, appropriate for gestational age babies . Clinical presentation is indistinguishable from Gram negative septicemia . Life threatening complications can also occur . Ciprofloxacin may prove to be useful drug in resistant cases. Eur J Clin Microbiol Infect Dis, 1998 Apr, 17(4), 282 - 5 Carbapenem resistance mediated by beta-lactamases in clinical isolates of Acinetobacter baumannii in Spain; Lopez-Hernandez S et al.; Four patients colonized/infected with carbapenem-resistant strains of Acinetobacter baumannii are described . The first patient had a decubitus ulcer infection and had been on intravenous imipenem for 50 days . Two other patients, from whom Acinetobacter baumannii was isolated from urine, were hospitalized in the same ward as the first patient . The fourth patient had been mechanically ventilated in the intensive care unit for 4 month and had nosocomial pneumonia . He had been on intravenous meropenem for 1 month . Minimum inhibitory concentrations (MICs) of imipenem (128 mg/l) and meropenem (> 128 mg/l) were the same for the isolates from the first three patients, and all of these isolates had the same repetitive extragenic palindromic polymerase chain reaction (rep-PCR) pattern . The MICs of carbapenems were lower for patient 4's isolate, which also had a different rep-PCR pattern . Beta-lactamases that hydrolyzed imipenem were detected in all four isolates; isoelectric points were 8.6-7.7 in the first three isolates and 6.8-7 in the fourth isolate. Eur J Clin Microbiol Infect Dis, 1998 Apr, 17(4), 247 - 53 Detection of bacteraemia in patients with fever and neutropenia using 16S rRNA gene amplification by polymerase chain reaction; Ley BE et al.; Episodes of fever and neutropenia are common complications of treatment for cancer . The use of prophylactic and early empirical antibiotics has reduced mortality but decreases the sensitivity of diagnostic tests based on culture . The aim of this study was to determine the potential of a broad diagnostic approach (eubacterial) based on 16S rRNA gene amplification and sequencing to augment cultural methods of diagnosis of bacteraemia in patients with fever and neutropenia in a regional paediatric oncology centre . One hundred eleven patient-episodes of fever and neutropenia were evaluated during the study period, 17 of which were associated with positive blood cultures, as follows: Staphylococcus epidermidis (n = 6 episodes), Enterococcus faecium (n = 2), Streptococcus sanguis (n = 3), Streptococcus mitis (n = 3), Staphylococcus aureus (n = 1), Micrococcus spp . (n = 1), and Stenotrophomonas maltophilia (n = 1) . Eubacterial polymerase chain reaction (PCR) detected bacterial DNA in nine of 11 blood culture-positive episodes for which a sample was available for PCR; the species identified by sequence analysis were identical to those derived from the conventional identification of the cultured isolates . Bacterial DNA was detected in 20 episodes (21 bacterial sequences) associated with negative blood cultures, 18 of which occurred in patients who were receiving antibiotics at the time of sample collection . The species presumptively identified by partial 16S rRNA gene sequencing were as follows: Pseudomonas spp . (n = 6 episodes), Acinetobacter spp . (n =5 ); Escherichia spp . (n = 3); Moraxella spp . (n = 3); Staphylococcus spp . (n = 2); Neisseria spp . (n = 1); and Bacillus spp . (n = 1) . The results of this study suggest that molecular techniques can augment cultural methods in the diagnosis of bacteraemia in patients who have been treated with antibiotics. J Clin Microbiol, 1998 Sep, 36(9), 2522 - 9 Comparison of amplified ribosomal DNA restriction analysis, random amplified polymorphic DNA analysis, and amplified fragment length polymorphism fingerprinting for identification of Acinetobacter genomic species and typing of Acinetobacter baumannii; Koeleman JG et al.; Thirty-one strains of Acinetobacter species, including type strains of the 18 genomic species and 13 clinical isolates, were compared by amplified ribosomal DNA restriction analysis (ARDRA), random amplified polymorphic DNA analysis (RAPD), and amplified fragment length polymorphism (AFLP) fingerprinting . ARDRA, performed with five different enzymes, showed low discriminatory power for differentiating Acinetobacter at the species and strain level . The standardized commercially available RAPD kit clearly enabled the discrimination of all Acinetobacter genomic species but showed great polymorphism between isolates of Acinetobacter baumannii . AFLP fingerprinting with radioactively as well as fluorescently labelled primers showed high discriminatory power for the identification of 18 Acinetobacter genomic species and typing of 13 clinical Acinetobacter isolates . Compared to radioactive AFLP, fluorescent AFLP was technically fast and simple to perform, and it permitted analysis with an automated DNA sequencer . Fluorescent AFLP seems particularly well suited for studying the epidemiology of nosocomial infections and outbreaks caused by Acinetobacter species. Zhonghua Yi Xue Za Zhi (Taipei), 1998 Jul, 61(7), 408 - 13 Activity of cefepime compared with other antibiotics against gram-positive bacteria and cefuroxime-resistant gram-negative bacteria; Wang FD et al.; BACKGROUND: Cefepime is a new, parenteral, fourth-generation antibiotic that is stable in the presence of Bush group 1 beta-lactamases . In vitro activity of cefepime, cefuroxime, ceftazidime, ciprofloxacin and imipenem against Gram-positive cocci and cefuroxime-resistant Gram-negative bacilli was studied . METHODS: The agar dilution method described by the US National Committee for Clinical Laboratory Standards was used to determine the minimum inhibitory concentrations of antibiotics tested . These included cefepime, cefuroxime, ceftazidime, ciprofloxacin and imipenem . The tested clinical isolates included Gram-positive cocci (methicillin-sensitive coagulase-negative staphylococci, methicillin-resistant coagulase-negative staphylococci, methicillin-sensitive Staphylococcus aureus, methicillin-resistant S aureus, Streptococcus pyogenes, viridans streptococci, Streptococcus pneumoniae, group D enterococci) and cefuroxime-resistant Gram-negative bacilli (Escherichia coli, Klebsiella pneumoniae, Acinetobacter spp, Pseudomonas aeruginosa, Enterobacter cloacae, Serratia marcescens, Burkholderia cepacia and Xanthomonas maltophilia) . RESULTS: The activity of cefepime against most Gram-negative bacilli other than B cepacia and X maltophilia is better than that of ceftazidime . However, cefepime is less active against these Gram-negative bacilli than ciprofloxacin and imipenem . The activity of cefepime against B cepacia and X maltophilia is less than that of ceftazidime or ciprofloxacin . Among Gram-positive cocci, cefepime was active against most isolates of methicillin-sensitive staphylococci, S pyogenes, viridans streptococci and S pneumoniae . However, cefepime has poor activity against methicillin-resistant S aureus and enterococci . CONCLUSIONS: Due to its extended spectrum of activity, cefepime has potential use as suitable empiric monotherapy for the treatment of a variety of community- and hospital-acquired infections. J Hosp Infect, 1998 Jul, 39(3), 235 - 40 Exceptional desiccation tolerance of Acinetobacter radioresistens; Jawad A et al.; The taxonomy of the genus Acinetobacter, which includes several important nosocomial pathogens, has been confused due to a lack of discriminatory phenotypic characteristics for identification . Molecular methods such as amplified ribosomal DNA restriction analysis (ARDRA) now enable the accurate identification of species . Ten clinical isolates of Acinetobacter radioresistens had genospecies confirmed by ARDRA but the APJ 20NE system, commonly used in clinical microbiology laboratories, mis-identified them as Acinetobacter lwoffii . Desiccation resistance of Acinetobacter spp . is an important attribute for their survival in the clinical environment . We investigated the ability of A . radioresistens to survive desiccation using an established glass surface model and compared the results to A . lwoffii and Acinetobacter baumannii . The 10 strains of A . radioresistens were extremely resistant to desiccation and survived for an average of 157 days at 31% relative humidity (RH) . In contrast, two strains of A . lwoffii and three strains of A . baumannii survived for an average of three and 20 days respectively, at 31% RH, which was used as an approximation to climatic conditions in UK hospitals . A . radioresistens is thus well adapted for survival in the hospital environment and carriage on human skin and yet it is reported less frequently than A . lwoffii amongst clinical isolates . Cases of A . radioresistens infection may be under-reported due to mis-identification as A . lwoffii and further studies that use molecular identification methods are required to elucidate the role of A . radioresistens in human disease. J Hosp Infect, 1998 Jul, 39(3), 195 - 206 Changing bacterial ecology during a five-year period of selective intestinal decontamination; Lingnau W et al.; The development of bacterial resistance during selective decontamination of the digestive tract (SDD) is controversial . We studied effects on bacterial resistance one year before and during a randomized, placebo-controlled trial of SDD in a surgical intensive care unit . We randomized patients within two different topical regimens (PTA, PCA) or placebo, administered four-times daily to both the oropharynx and gastrointestinal tract . All patients received intravenous ciprofloxacin (200 mg b.d.) for four days . Both SDD regimens successfully reduced aerobic Gram-negative intestinal colonization . There was no increase in resistance of Enterobacteriaceae or Pseudomonas aeruginosa . Acinetobacter calcoaceticus developed multi-resistance over one year, but differences between groups were not significant . We detected a shift towards Gram-positive organisms . Oxacillin-resistant Staphylococcus aureus increased in concert with ciprofloxacin resistance, from 17 to 80.7%, and frequencies of resistance were significantly higher in SDD patients (P < 0.001) . Resistance of coagulase-negative staphylococci (CNS) to oxacillin increased initially (25 to 66.9%), but values returned to baseline in controls . Ciprofloxacin resistance in CNS remained higher (P < 0.001) in SDD-treated patients (52.5 vs . 23.3%) . The incidence of late respiratory tract infections was unaltered by the prophylactic regimen (SDD 35.2%; Placebo 41.2%; n.s.) . We cannot recommend SDD as a prophylactic tool in critically ill patients. Ann Intern Med, 1998 Aug 1, 129(3), 182 - 9 Nosocomial Acinetobacter baumannii infections: microbiological and clinical epidemiology; Villers D et al.; BACKGROUND: Acinetobacter baumannii is an important opportunistic pathogen that is rapidly evolving toward multidrug resistance and is involved in various nosocomial infections that are often severe . It is difficult to prevent A . baumannii infection because A . baumannii is ubiquitous and the epidemiology of the infections it causes is complex . OBJECTIVE: To study the epidemiology of A . baumannii infections and assess the relation between fluoroquinolone use and the persistence of multidrug-resistant clones . DESIGN: Three case-control studies and a retrospective cohort study . SETTING: A 20-bed medical and surgical intensive care unit . PATIENTS: Acinetobacter baumannii was isolated from 45 patients in urine (31%), the lower respiratory tract (26.7%), wounds (17.8%), blood (11.1%), skin (6.7%), cerebrospinal fluid (4.4%), and sinus specimens (2.2%) . One death was due to A . baumannii infection . MEASUREMENTS: Antimicrobial resistance pattern and molecular typing were used to characterize isolates . The incidence of A . baumannii infection and the use of fluoroquinolones were calculated annually . RESULTS: Initially, 28 patients developed A . baumannii infection . Eleven isolates had the same antimicrobial susceptibility profile, genotypic profile, or both (epidemic cases), and 17 were heterogeneous (endemic cases) . A surgical procedure done in an emergency operating room was the main risk factor for epidemic cases, whereas previous receipt of a fluoroquinolone was the only risk factor for endemic cases . The opening of a new operating room combined with the restriction of fluoroquinolone use contributed to a transitory reduction in the incidence of infection . When a third epidemiologic study was done, previous receipt of a fluoroquinolone was again an independent risk factor and a parallel was seen between the amount of intravenous fluoroquinolones prescribed and the incidence of endemic infection . CONCLUSION: Epidemic infections coexisted with endemic infections favored by the selection pressure of intravenous fluoroquinolones. Eur J Biochem, 1998 Jul 1, 255(1), 255 - 61 Negative cooperativity in the steady-state kinetics of sugar oxidation by soluble quinoprotein glucose dehydrogenase from Acinetobacter calcoaceticus; Olsthoorn AJ et al.; Steady-state-kinetics investigations were carried out for the oxidation of aldose sugars by soluble quinoprotein glucose dehydrogenase (GDH) from Acinetobacter calcoaceticus using N-methylphenazonium methyl sulfate (PMS) as artificial electron acceptor . As is not uncommon for a dye-linked dehydrogenase, the enzyme showed ping-pong behaviour and double-substrate inhibition . However, under conditions that avoided its masking by sugar-substrate inhibition as much as possible, negative kinetic cooperativity with respect to sugar substrate oxidation by this enzyme was demonstrated . Arguments are presented that exclude trivial factors as a cause for the phenomenon observed . Experimental data could be fitted with an equation accounting for biphasic cooperativity containing two sets of apparent kinetic parameters, V1 and K1, and V1 and K2, representing the enzyme's Michaelis-Menten behaviour at low and high substrate concentrations, respectively . Assuming that subunit interaction causes the cooperativity effect, the sets express the performance of soluble GDH's two subunits in two states of mutual interaction . From fitting the experimental data for several sugars with this equation, it appeared that their V1 values were similar, although their K1 values varied considerably . This showed that the cooperativity effect dramatically changes the performance of soluble GDH, as reflected by the V2 and K2 values for glucose (in phosphate buffer) being about 10-fold and 100-fold higher than the V1 and K1 values, respectively . Substituting the Ca2+ involved in activation of pyrroloquinoline quinone (PQQ) in soluble GDH by Sr2+ affected the cooperativity effect (an increase of the K1 value) but not the two turnover rates of the hybrid enzyme for glucose . The data suggest that the two catalytic cycles of soluble GDH have different rate-limiting steps compared with that of PQQ-containing methanol dehydrogenase. Carbohydr Res, 1998 Jan, 306(1-2), 257 - 63 Structure of the O-7 antigen from Acinetobacter baumannii; Haseley SR et al.; The polymeric O-antigen was isolated from the lipopolysaccharide of the reference of the reference strain for Acinetobacter baumannii serogroup O-7 . Both the lipopolysaccharide and the isolated polymer reacted with the homologous antiserum . Monosaccharide analyses and NMR spectra showed that the polymer had a hexasaccharide repeating unit constructed from residues of L-rhamnose (4) and N-acetyl-D-glucosamine (2) . The following structure for the repeating unit was established by means of detailed interpretation of the NMR spectra, methylation analysis, and chemical degradations . The tetrasaccharide backbone is identical to that for the O-10 antigen of A . baumannii, which has alpha-D-ManpNAc as the lateral substituent in place of the disaccharide present in the O-7 antigen . {formula: see text} Burns, 1998 Jun, 24(4), 354 - 61 Burn septicaemia: an analysis of 79 patients; Bang RL et al.; Out of 943 patients treated from June 92 to May 96 at the burns unit of the Al-Babtain Centre for Plastic Surgery and Burns, Kuwait, 280 (30%) required admission to the burns intensive care unit (ICBU) and were studied retrospectively . Seventy-nine (28.2%) developed clinically and microbiologically proven septicaemia . Forty-four (56%) were males, 35 (44%) females with a mean age of 26 years (range 45 days to 75 years) and mean total body surface area burn (TBSA) of 46% (range 10-90%) . Sixty-two had flame burns, 16 a scald and one had an electric burn . These 79 patients had a total of 118 septicaemic episodes . Sixty (76%) had only one and 19 (24%) had multiple episodes of septicaemia . Fifty-four (68%) had their first episode within 2weeks, though the maximum number of episodes was between 6 and 10 days postburn . Septicaemia was also observed in 13% of patients within 3 days postburn . Out of the 118 episodes, 48 were due to methicillin resistant Staphylococcus aureus (MRSA), 17 due to methicillin resistant Staphylococcus epidemidis (MRSE), 15 to Pseudomonas, 12 to Acinetobacter, four to Streptococcus, another four to Enterococci, two to Klebsiella, one due to Serratia and 15 to more than one organism . Once the septicaemia was diagnosed appropriate therapy was instituted . Fifty-six (71%) patients had 143 sessions of skin grafting and the mortality was low in operated patients . Twenty-three (29.1%) patients died . The low mortality rate was probably due to factors such as continuous clinical and microbiological surveillance leading to quick detection of aetiology, appropriate antibiotic therapy, care for nutrition and early wound cover . This study suggests that flame burn patients are more vulnerable to sepsis . Onset of septicaemia may be as early as 3 days and commonly within 2 weeks . A surface wound is the likely source of entry to the blood stream . Gram positive organisms are dominant in the aetiology . Early detection and appropriate treatment including wound coverage result in a better outcome. Appl Environ Microbiol, 1998 Aug, 64(8), 3110 - 3 Specific ribosomal DNA sequences from diverse environmental settings correlate with experimental contaminants; Tanner MA et al.; Phylogenetic analysis of 16S ribosomal DNA (rDNA) clones obtained by PCR from uncultured bacteria inhabiting a wide range of environments has increased our knowledge of bacterial diversity . One possible problem in the assessment of bacterial diversity based on sequence information is that PCR is exquisitely sensitive to contaminating 16S rDNA . This raises the possibility that some putative environmental rRNA sequences in fact correspond to contaminant sequences . To document potential contaminants, we cloned and sequenced PCR-amplified 16S rDNA fragments obtained at low levels in the absence of added template DNA . 16S rDNA sequences closely related to the genera Duganella (formerly Zoogloea), Acinetobacter, Stenotrophomonas, Escherichia, Leptothrix, and Herbaspirillum were identified in contaminant libraries and in clone libraries from diverse, generally low-biomass habitats . The rRNA sequences detected possibly are common contaminants in reagents used to prepare genomic DNA . Consequently, their detection in processed environmental samples may not reflect environmentally relevant organisms. FEMS Microbiol Lett, 1998 Jul 1, 164(1), 169 - 75 Distribution of mevalonate and glyceraldehyde 3-phosphate/pyruvate routes for isoprenoid biosynthesis in some gram-negative bacteria and mycobacteria; Putra SR et al.; Labeling experiments using {1-13C}acetate or {1-13C}glucose were performed with opportunistic pathogenic bacteria, with innocuous bacteria related to pathogenic species or with phytopathogenic species . The labeling pattern was determined in the isoprenic moiety of ubiquinone or menaquinone derivatives . These experiments showed that Acinetobacter, Citrobacter, Erwinia, Pseudomonas, Burkholderia, Ralstonia and Mycobacterium synthesize their isoprenoids via the mevalonate-independent glyceraldehyde 3-phosphate/pyruvate route . Enzymes of this novel bacterial metabolic route, which is apparently absent in vertebrates and man, therefore represent potential targets for a novel type of antibacterial drugs. Lett Appl Microbiol, 1998 May, 26(5), 359 - 62 Detection of carboxypeptidases as taxonomic markers for gram-negative bacteria; Perry JD et al.; The use of seven benzoyl-L-amino acids for the detection of carboxypeptidase activities in strains of Gram-negative aerobic and facultatively anaerobic bacteria is reported . A simple overnight assay was designed using ninhydrin for the demonstration of the amino acid released by hydrolysis . Detection of carboxypeptidase activity was shown to have some taxonomic relevance within the Enterobacteriaceae; it was also useful for differentiation within the genus Acinetobacter and for distinction between Pseudomonas aeruginosa and Pseudomonas fluorescens. Arch Virol, 1997, 142(12), 2329 - 45 A catalogue of T4-type bacteriophages; Ackermann HW et al.; The T4-type of bacteriophages is broadly defined on the basis of particle morphology . It occurs in enterobacteria (125 representatives), acinetobacters, aeromonads, pseudomonads, and vibrios (16 isolates) . In addition, 18 apparently unrelated phages with prolate heads and contractile tails are found in a wide range of bacteria . A descriptive catalogue of these phages is presented . The T4-type probably originated in precursors of enterobacteria. J Chemother, 1998 Jun, 10(3), 236 - 42 Bacteremia and fungemia in pediatric versus adult cancer patients after chemotherapy: comparison of etiology, risk factors and outcome; Krupova I et al.; One hundred and eighteen (118) episodes of bacteremia and fungemia in children with cancer were compared to 401 episodes of bacteremia and fungemia in adults with cancer to assess differences in etiology, risk factors and outcome . A retrospective univariate analysis was performed of all episodes of bacteremia in national pediatric and adult cancer institutions appearing in 1990-1996 . A total of 519 episodes of bacteremia were assessed and compared . Both cancer centers differed in prophylactic antibiotic policies . About 50% of adults but less than 5% of children received quinolone prophylaxis during neutropenia, even though the empiric antibiotic therapeutic strategy was similar . There were differences in etiology between the groups: staphylococci and Stenotrophomonas maltophilia were more frequently observed in children (P<0.01), Pseudomonas aeruginosa and Acinetobacter spp . in adults (P<0.05) . Gram-positive bacteremia was surprisingly more commonly observed in adults (65.7% vs 33.3%, P<0.01) . Mixed polymicrobial bacteremia occurred more commonly in adults (31.8% vs 7.6%, P<0.001) than in children . Analysis of risk factors did not observe differences in risk factors except for underlying disease (acute leukemia was more frequently observed in children -48.3% vs adults 33.7%, P<0.05 and prophylaxis: (prior prophylaxis with quinolones was more common in adults (47.5%) than in children (2.5%) P<0.0001) . Overall and attributable mortality in pediatric bacteremia was significantly lower than in adults (P<0.03). J Chemother, 1998 Jun, 10(3), 215 - 20 Further studies of transferable antibiotic resistance in strains of Pseudomonas aeruginosa from four clinical settings in three countries; Blahova J et al.; This paper describes transferability of antibiotic resistance determinants in clinical isolates of Pseudomonas aeruginosa resistant to imipenem, cefotaxime and ceftazidime obtained from different clinical settings in three different countries . Two strains of Enterobacteriaceae (Escherichia coli K-12 and Proteus mirabilis P-38) and two strains of P . aeruginosa (PAO and ML) were used as recipient strains . The conjugative transfer of resistance was very specific, i.e . donor strains of P . aeruginosa transferred individual resistance determinants either to recipient strains E . coli K-12 and P . mirabilis P-38, or to P . aeruginosa PAO or ML . In a case when three different species (P . aeruginosa, Acinetobacter calcoaceticus, Stenotrophomonas maltophilia) were isolated from a single patient, a block of resistance determinants was transferred both to Enterobacteriaceae and P . aeruginosa recipients . A single plasmid with rather specific properties was suspected of being exchanged among strains of these different species . It was recommended to study the overall situation of transferability of individual resistance determinants in bacterial strains belonging to various species of nosocomial bacteria, especially of P . aeruginosa, by using a rather specific methodology. J Chemother, 1998 Jun, 10(3), 208 - 14 In vitro activity of piperacillin/tazobactam versus other broad-spectrum antibiotics against nosocomial gram-negative pathogens isolated from burn patients; Mokaddas E et al.; Burn patients are at high risk for nosocomial infections due to multiresistant bacteria, a large proportion of which are gram-negative . Tazobactam, a potent inhibitor of beta-lactamases, extends the spectrum of piperacillin to include many beta-lactamase producing bacteria . Consequently, it was decided to evaluate the activity of piperacillin/tazobactam in comparison with that of eight other antibiotics that are usually used for therapy against gram-negative bacterial infections in our burn unit . All consecutive gram-negative isolates from wounds, blood, respiratory tract, urine etc . from burn patients considered to be clinically significant were tested for their susceptibility to piperacillin/tazobactam, piperacillin, ceftazidime, cefotaxime, ceftriaxone, ciprofloxacin, gentamicin, amikacin and imipenem, determined by disk diffusion test . The zone inhibition was interpreted according to NCCLS recommendations . A total of 948 strains, isolated during the period of July, 1994 to September, 1995, made up of Pseudomonas spp (326), Acinetobacter spp (268) and Enterobacteriaceae (354), were tested . Overall piperacillin/tazobactam showed superior activity over the other antibiotics except for imipenem . Of the 948 isolates, 87% were susceptible to the combination, 56% to the three third generation cephalosporins, 69% to ciprofloxacin, 59% to the aminoglycosides and 97% to imipenem . Piperacillin/tazobactam showed strikingly superior activity over piperacillin alone against Acinetobacter spp followed by Enterobacteriaceae and the least against Pseudomonas . The emergence of Acinetobacter spp as a dominant gram-negative pathogen in burn patients and its high level of resistance against most of the antibiotics tested except piperacillin/tazobactam (87%) and imipenem (100%) were significant in light of the epidemiology of burn infections and treatment . This study suggests that piperacillin/tazobactam holds good promise against gram-negative infections in burn patients. Eur J Clin Microbiol Infect Dis, 1998 Mar, 17(3), 171 - 6 Surveillance of an adult intensive care unit for long-term persistence of a multi-resistant strain of Acinetobacter baumannii; Webster CA et al.; Sporadic infections with Acinetobacter spp., punctuated with prolonged outbreaks of infection involving larger numbers of patients and a particular epidemic strain of Acinetobacter baumannii, have occurred in the adult intensive care unit (ICU) of Nottingham University Hospital since 1985 . The aim of this study was to screen patients admitted to the ICU for three or more days during a non-outbreak period in 1994-1995 and to use DNA fingerprinting techniques to compare any isolates of Acinetobacter spp . with isolates obtained from the same ICU during the previous ten years . In the present study, almost 20% of the ICU patients screened during 1994-1995 became colonized with Acinetobacter spp . The commonest species isolated from patients was Acinetobacter baumannii; five different strains were identified by random amplified polymorphic DNA fingerprinting, including the epidemic strain responsible for outbreaks of infection in 1985-1986 and 1992-1993 . Environmental sampling yielded Acinetobacter spp . from one or more samples on four occasions; Acinetobacter radioresistens was the commonest species isolated, and Acinetobacter baumannii (not the epidemic strain) was isolated on only one occasion from the environment . The long-term persistence of a potentially epidemic strain in the ICU, even during a non-outbreak period, indicates a need for continued vigilance . Consequently, periodic patient and environmental surveillance, combined with typing of isolates, is recommended for ICUs where significant outbreaks of Acinetobacter infection have occurred in the past. Blood Coagul Fibrinolysis, 1998 Apr, 9(3), 227 - 32 Reconstituted recombinant factor VIII can be safely infused continuously for at least three days: it is a poor microbial growth medium; Didier ME et al.; Reconstituted recombinant factor VIII (FVIIIrec) loses little biologic activity at room temperature for up to seven days and continuous infusion is convenient, effective hemostatically and requires less FVIIIrec concentrate than treatment by conventional bolus injections . However, the potential for bacterial contamination, with proliferation to high levels that can cause bacteremia, is a concern with continuous infusion . We studied the growth properties at 4, 25 and 35 degrees C in reconstituted FVIIIrec (Kogenate) and at 25 degrees C in 5% dextrose in water (D5%W) of three isolates each of Staphylococcus epidermidis, Staphylococcus aureus, Enterobacter cloacae, Klebsiella oxytoca, Serratia marcescens, Acinetobacter calcoaceticus, Stenotrophomonas maltophilia, Pseudomonas aeruginosa, Burkholderia cepacia, Flavobacterium spp . and Candida albicans, species most likely to contaminate infusate during preparation or administration and which have been implicated in more than 95% of all outbreaks and sporadic cases of nosocomial bloodstream infection traced to contaminated admixtures, biologic agents or medications administered parenterally . Reconstituted FVIIIrec allowed growth of only three species at 25 degrees C and 35 degrees C: S . marcescens, S . maltophilia and P . aeruginosa; logarithmic growth appeared only after 24-48 h . D5%W allowed growth of two gram-negative species, S . marcescens and B . cepacia . We conclude that reconstituted FVIIIrec (Kogenate) is a poor growth medium for most nosocomial pathogens, comparable with D5%W . If reconstituted aseptically, continuous infusion of reconstituted FVIIIrec should be safe, and it should not be necessary to replace the container or tubing more frequently than every 3 days, an administration schedule that can provide effective hemostasis at lower cost. Eur J Biochem, 1998 Jun 1, 254(2), 404 - 12 Cloning and characterization of 3-deoxy-D-manno-oct-2-ulosonic acid (Kdo) transferase genes (kdtA) from Acinetobacter baumannii and Acinetobacter haemolyticus; Bode CE et al.; 3-Deoxy-D-manno-oct-2-ulosonic acid (Kdo) transferases (KdtA) are multifunctional glycosyltransferases with primary structures of low similarity . Totally degenerated primers were deduced from two stretches of identical amino acids between known KdtA sequences and used to amplify by PCR a kdtA-specific fragment from Acinetobacter baumannii ATCC 15308 DNA which was then applied as a probe for the cloning and sequencing of the complete Kdo transferase gene . With conserved PCR primers for this structural gene from A . baumannii ATCC 15308, also kdtA genes of A . baumannii ATCC 19606 and A . haemolyticus ATCC 17906 were obtained, cloned from the chromosome and sequenced . The genes coded for proteins with similarities to known Kdo transferases . Within the genus Acinetobacter, the identity and similarity of the deduced amino acid sequences were 71% and 84.5%, respectively . The kdtA sequences of both A . baumannii strains were identical and possessed a TTG start codon, whereas ATG was found in the case of A . haemolyticus . The genes from Acinetobacter and kdtA from Escherichia coli K-12 were expressed in the Gram-positive bacterium Corynebacterium glutamicum . In vitro tests confirmed the function of the gene products as Kdo transferases, which transferred mainly two Kdo residues to a synthetic lipid A precursor of E . coli . Also, no differences between the cloned kdtA genes from A . baumanniii, A . haemnolyticus and E . coli were observed when tetraacyl or hexaacyl lipid A were tested, since all transferases acted more efficiently on the former . With limiting amounts of acceptor, all Kdo transferases were able to transfer a third Kdo residue with varying efficiency. New Horiz, 1998 May, 6(2 Suppl), S30 - 45 Ventilator-associated bacterial pneumonia: challenges in diagnosis, treatment, and prevention; Craven DE et al.; Ventilator-associated pneumonia (VAP) is a common infection in intensive care unit patients that results in high mortality and morbidity and increased duration of hospital stay . Clinical diagnostic methods are sensitive, but lack specificity . Quantitative analysis of specimens from the lower respiratory tract increases specificity . Bacteria causing VAP may originate from the patient's endogenous flora, other patients or hospital personnel, or from environmental sources . Aspiration or direct inoculation are the major routes of bacterial entry into the lower respiratory tract . The bacterial inoculum and host response in the lung are important factors for pathogenesis . Late-onset nosocomial pneumonia is often caused by Pseudomonas aeruginosa, Acinetobacter species, and Staphylococcus aureus . Streptococcus pneumoniae and Haemophilus influenzae, however, are the more common pathogens in early-onset disease . Oropharyngeal and gastric colonization with bacteria, cross-infection, as well as the indiscriminate use of antibiotics or invasive devices substantially increase the risk of VAP . An understanding of the epidemiology and pathogenesis of VAP, along with implementation of appropriate preventive measures, are needed to decrease the incidence, morbidity, and mortality associated with VAP. J Clin Microbiol, 1998 Jul, 36(7), 1938 - 41 Survival of Acinetobacter baumannii on dry surfaces: comparison of outbreak and sporadic isolates; Jawad A et al.; Acinetobacter spp . are important nosocomial pathogens reported with increasing frequency in outbreaks of cross-infection during the past 2 decades . The majority of such outbreaks are caused by Acinetobacter baumannii . To investigate whether desiccation tolerance may be involved in the ability of certain strains of A . baumannii to cause hospital outbreaks, a blind study was carried out with 39 epidemiologically well-characterized clinical isolates of A . baumannii for which survival times were determined under simulated hospital conditions . The survival times on glass coverslips of 22 strains isolated from eight well-defined hospital outbreaks in a German metropolitan area were compared with the survival times of 17 sporadic strains not involved in outbreaks but rather isolated from inpatients in the same geographic area . All sporadic isolates have been shown by pulsed-field gel electrophoresis to represent different strain types . There was no statistically significant difference between the survival times of sporadic strains of A . baumannii and outbreak strains (27.2 versus 26.5 days, respectively; P < or = 0.44) by the Wilcoxon-Mann-Whitney test . All investigated A . baumannii strains, irrespective of their areas of endemicity or epidemic occurrence, have the ability to survive for a long time on dry surfaces . Antimicrobial susceptibility testing showed that A . baumannii outbreak strains were significantly more resistant to various broad-spectrum antimicrobial agents than sporadic strains . Both desiccation tolerance and multidrug resistance may contribute to their maintenance in the hospital setting and may explain in part their propensity to cause prolonged outbreaks of nosocomial infection. Infection, 1998 May-Jun, 26(3), 155 - 9 Gram-negative bacteremia in non-neutropenic patients: a 3-year review; Gikas A et al.; The causative organisms, clinical manifestations, factors influencing prognosis, and other epidemiological charac