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SUMMARYThis study was performed to determine the prevalence, distribution of specimen sources, and antimicrobial susceptibility of the Acinetobacter calcoaceticus-Acinetobacter baumannii (Acb) species complex in Singapore. One hundred and ninety-three non-replicate Acb species complex clinical isolates were collected from six hospitals over a 1-month period in 2006. Of these, 152 (78·7%) were identified as A. baumannii, 18 (9·3%) as 'Acinetobacter pittii' [genomic species (gen. sp.) 3], and 23 (11·9%) as 'Acinetobacter nosocomialis' (gen. sp. 13TU). Carbapenem resistance was highest in A. baumannii (72·4%), followed by A. pittii (38·9%), and A. nosocomialis (34·8%). Most carbapenem-resistant A. baumannii and A. nosocomialis possessed the blaOXA-23-like gene whereas carbapenem-resistant A. pittii possessed the blaOXA-58-like gene. Two imipenem-resistant strains (A. baumannii and A. pittii) had the blaIMP-like gene. Representatives of carbapenem-resistant A. baumannii were related to European clones I and II. [ABSTRACT FROM AUTHOR]

Background: In adults with febrile urinary tract infection (fUTI), data on optimal treatment duration in patients other than non-pregnant women without comorbidities are lacking., Methods: A randomized placebo-controlled, double-blind, non-inferiority trial among 35 primary care centers and 7 emergency departments of regional hospitals in the Netherlands. Women and men aged ≥ 18 years with a diagnosis of fUTI were randomly assigned to receive antibiotic treatment for 7 or 14 days (the second week being ciprofloxacin 500 mg or placebo orally twice daily). Patients indicated to receive antimicrobial treatment for at least 14 days were excluded from randomization. The primary endpoint was the clinical cure rate through the 10- to 18-day post-treatment visit with preset subgroup analysis including sex. Secondary endpoints were bacteriologic cure rate at 10-18 days post-treatment and clinical cure at 70-84 days post-treatment., Results: Of 357 patients included, 200 were eligible for randomization; 97 patients were randomly assigned to 7 days and 103 patients to 14 days of treatment. Overall, short-term clinical cure occurred in 85 (90%) patients treated for 7 days and in 94 (95%) of those treated for 14 days (difference -4.5%; 90% CI, -10.7 to 1.7; P non-inferiority  = 0.072, non-inferiority not confirmed). In women, clinical cure was 94% and 93% in those treated for 7 and 14 days, respectively (difference 0.9; 90% CI, -6.9 to 8.7, P non-inferiority  = 0.011, non-inferiority confirmed) and, in men, this was 86% versus 98% (difference -11.2; 90% CI -20.6 to -1.8, P superiority  = 0.025, inferiority confirmed). The bacteriologic cure rate was 93% versus 97% (difference -4.3%; 90% CI, -9.7 to 1.2, P non-inferiority  = 0.041) and the long-term clinical cure rate was 92% versus 91% (difference 1.6%; 90% CI, -5.3 to 8.4; P non-inferiority  = 0.005) for 7 days versus 14 days of treatment, respectively. In the subgroups of men and women, long-term clinical cure rates met the criteria for non-inferiority, indicating there was no difference in the need for antibiotic retreatment for UTI during 70-84 days follow-up post-treatment., Conclusions: Women with fUTI can be treated successfully with antibiotics for 7 days. In men, 7 days of antibiotic treatment for fUTI is inferior to 14 days during short-term follow-up but it is non-inferior when looking at longer follow-up., Trial Registration: The study was registered at ClinicalTrials.gov [ NCT00809913 ; December 16, 2008] and trialregister.nl [ NTR1583 ; December 19, 2008].

Multidrug resistant Acinetobacter baumannii and its closely related species A. pittii and A. nosocomialis, all members of the Acinetobacter calcoaceticus-baumannii (Acb) complex, are a major cause of hospital acquired infection. In the burn wound center of the Queen Astrid military hospital in Brussels, 48 patients were colonized or infected with Acb complex over a 52-month period. We report the molecular epidemiology of these organisms, their clinical impact and infection control measures taken. A representative set of 157 Acb complex isolates was analyzed using repetitive sequence-based PCR (rep-PCR) (DiversiLab) and a multiplex PCR targeting OXA-51-like and OXA-23-like genes. We identified 31 rep-PCR genotypes (strains). Representatives of each rep-type were identified to species by rpoB sequence analysis: 13 types to A. baumannii, 10 to A. pittii, and 3 to A. nosocomialis. It was assumed that isolates that belonged to the same rep-type also belonged to the same species. Thus, 83.4% of all isolates were identified to A. baumannii, 9.6% to A. pittii and 4.5% to A. nosocomialis. We observed 12 extensively drug resistant Acb strains (10 A. baumannii and 2 A. nosocomialis), all carbapenem-non-susceptible/colistin-susceptible and imported into the burn wound center through patients injured in North Africa. The two most prevalent rep-types 12 and 13 harbored an OXA-23-like gene. Multilocus sequence typing allocated them to clonal complex 1 corresponding to EU (international) clone I. Both strains caused consecutive outbreaks, interspersed with periods of apparent eradication. Patients infected with carbapenem resistant A. baumannii were successfully treated with colistin/rifampicin. Extensive infection control measures were required to eradicate the organisms. Acinetobacter infection and colonization was not associated with increased attributable mortality.

The diagnosis of Pneumocystis pneumonia (PCP) relies on microscopic visualization of Pneumocystis jirovecii organisms or DNA detection in pulmonary specimens. This study aimed to assess the usefulness of (1-3)-β-d-glucan (BG), Krebs von den Lungen-6 antigen (KL-6), lactate dehydrogenase (LDH) and S-adenosyl methionine (SAM) as serologic biomarkers in the diagnosis of PCP. Serum levels of BG, KL-6, LDH and SAM were investigated in 145 Portuguese patients, 50 patients from the Netherlands, 25 Spanish patients and 40 Portuguese blood donors. Data on clinical presentation, chest imaging and gasometry tests were available. PCP cases were confirmed by microscopy and PCR techniques. A cost-effectiveness analysis was performed. BG was found to be the most reliable serologic biomarker for PCP diagnosis, followed by KL-6, LDH and SAM. The BG/KL-6 combination test was the most accurate serologic approach for PCP diagnosis, with 94.3% sensitivity and 89.6% specificity. Although less sensitive/specific than the reference standard classic methods based on bronchoalveolar lavage followed by microscopic or molecular detection of P. jirovecii organisms, the BG/KL-6 test may provide a less onerous procedure for PCP diagnosis, as it uses a minimally invasive and inexpensive specimen (blood), which may be also a major benefit for the patient's care. The BG/KL-6 combination test should be interpreted within the clinical context, and it may be used as a preliminary screening test in patients with primary suspicion of PCP, or as an alternative diagnostic procedure in patients with respiratory failure or in children, avoiding the associated risk of complications by the use of bronchoscopy., (Copyright © 2014 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Objective/purpose: Febrile urinary tract infection (UTI) is a common bacterial disease that may lead to substantial morbidity and mortality especially among the elderly. Little is known about biomarkers that predict a complicated course. Our aim was to determine the role of certain urinary cytokines or antimicrobial proteins, plasma vitamin D level, and genetic variation in host defense of febrile UTI and its relation with bacteremia., Methods: A case-control study. Out of a cohort of consecutive adults with febrile UTI (n = 787) included in a multi-center observational cohort study, 46 cases with bacteremic E.coli UTI and 45 cases with non-bacteremic E.coli UTI were randomly selected and compared to 46 controls. Urinary IL-6, IL-8, LL37, β-defensin 2 and uromodulin as well as plasma 25-hydroxyvitamin D were measured. In 440 controls and 707 UTI patients polymorphisms were genotyped in the genes CXCR1, DEFA4, DEFB1, IL6, IL8, MYD88, UMOD, TIRAP, TLR1, TLR2, TLR5 and TNF., Results: IL-6, IL-8, and LL37 are different between controls and UTI patients, although these proteins do not distinguish between patients with and without bacteremia. While uromodulin did not differ between groups, inability to produce uromodulin is more common in patients with bacteremia. Most participants in the study, including the controls, had insufficient vitamin D and, at least in winter, UTI patients have lower vitamin D than controls. Associations were found between the CC genotype of IL6 SNP rs1800795 and occurrence of bacteremia and between TLR5 SNP rs5744168 and protection from UTI. The rare GG genotype of IL6 SNP rs1800795 was associated with higher β-defensin 2 production., Conclusion: Although no biomarker was able to distinguish between UTI with or without bacteremia, two risk factors for bacteremia were identified. These were inability to produce uromodulin and an IL6 rs1800795 genotype.

Here we report a case of carbapenem resistance in a human clinical isolate that was found to be closely related to the newly described environmental species Acinetobacter indicus. This strain harboured the blaOXA-23 carbapenemase gene located on a conjugative plasmid. Partial sequencing of 16S rDNA and rpoB genes, together with matrix-assisted laser desorption/ionisation time-of-flight (MALDI-TOF) analysis, showed that this strain was distantly related to the Acinetobacter baumannii-calcoaceticus complex and was closely related to A. indicus., (Copyright © 2014. Published by Elsevier B.V.)

Population diversity, susceptibility to antibiotics including carbapenems of 277 Acinetobacter baumannii strains collected in 17 Italian hospitals over a 6-months' period was assessed. Semi-automated rep-PCR was used for screening strains for genotypic relatedness. AFLP analysis and MLST were used as definitive methods for strain, species and/or clone identification. Among the 277 strains, 49 rep-PCR types were distinguished with four types (1-4) predominant, indicating both intra- and interhospital spread. AFLP analysis allowed to distinguish 51 types and largely confirmed rep-typing results. Isolates with predominant rep-types 1 and 2 (in 3 and 9 hospitals) were allocated to EU clones I and II, respectively. Rep-type 3 (8 hospitals) belonged to a new clone ("Italian clone"). Rep-type 4 was found in 2 neighbouring hospitals. Two isolates from 2 locations belonged to EU clone III. Twenty-five isolates were identified by AFLP-analysis to A. pittii, emphasizing misidentification by phenotypic methods. MLST confirmed clone identification by AFLP; demonstrating also that the "Italian clone" was ST78, recently detected in different Mediterranean countries. Multidrug resistance, defined as resistance to 9 out of the 11 drugs tested, was common in 10 out of 17 hospitals. The high prevalence of carbapenem resistance was associated with OXA-58 found in 9 out of the 10 hospitals. A high percentage of noted very major errors in susceptibility testing, especially for amikacin and meropenem, was probably due to heteroresistant strains. The occurrence of carbapenem and multidrug resistance in A. baumannii was mainly confined to a limited number of clonal lineages of A. baumannii., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Acinetobacter genomic species (gen. sp.) 3 and gen. sp. 13TU are increasingly recognized as clinically important taxa within the Acinetobacter calcoaceticus-Acinetobacter baumannii (ACB) complex. To define the taxonomic position of these genomic species, we investigated 80 strains representing the known diversity of the ACB complex. All strains were characterized by AFLP analysis, amplified rDNA restriction analysis and nutritional or physiological testing, while selected strains were studied by 16S rRNA and rpoB gene sequence analysis, multilocus sequence analysis and whole-genome comparison. Results supported the genomic distinctness and monophyly of the individual species of the ACB complex. Despite the high phenotypic similarity among these species, some degree of differentiation between them could be made on the basis of growth at different temperatures and of assimilation of malonate, l-tartrate levulinate or citraconate. Considering the medical relevance of gen. sp. 3 and gen. sp. 13TU, we propose the formal names Acinetobacter pittii sp. nov. and Acinetobacter nosocomialis sp. nov. for these taxa, respectively. The type strain of A. pittii sp. nov. is LMG 1035(T) (=CIP 70.29(T)) and that of A. nosocomialis sp. nov. is LMG 10619(T) (=CCM 7791(T))., (Copyright © 2011 Institut Pasteur. Published by Elsevier SAS. All rights reserved.)

The epidemiology of Acinetobacter baumannii emerging in combat casualties is poorly understood. We analyzed 65 (54 nonreplicate) Acinetobacter isolates from 48 patients (46 hospitalized and 2 outpatient trainees entering the military) from October 2004 to October 2005 for genotypic similarities, time-space relatedness, and antibiotic susceptibility. Clinical and surveillance cultures were compared by amplified fragment length polymorphism (AFLP) genomic fingerprinting to each other and to strains of a reference database. Antibiotic susceptibility was determined, and multiplex PCR was performed for OXA-23-like, -24-like, -51-like, and -58-like carbapenemases. Records were reviewed for overlapping hospital stays of the most frequent genotypes, and risk ratios were calculated for any association of genotype with severity of Acute Physiology and Chronic Health Evaluation II (APACHE II) score or injury severity score (ISS) and previous antibiotic use. Nineteen genotypes were identified; two predominated, one consistent with an emerging novel international clone and the other unique to our database. Both predominant genotypes were carbapenem resistant, were present at another hospital before patients' admission to our facility, and were associated with higher APACHE II scores, higher ISSs, and previous carbapenem antibiotics in comparison with other genotypes. One predominated in wound and respiratory isolates, and the other predominated in wound and skin surveillance samples. Several other genotypes were identified as European clones I to III. Acinetobacter genotypes from recruits upon entry to the military, unlike those in hospitalized patients, did not include carbapenem-resistant genotypes. Acinetobacter species isolated from battlefield casualties are diverse, including genotypes belonging to European clones I to III. Two carbapenem-resistant genotypes were epidemic, one of which appeared to belong to a novel international clone.

The prevalence of the currently known Acinetobacter species and related trends of antimicrobial resistance in a Dutch university hospital were studied. Between 1999 and 2006, Acinetobacter isolates from clinical samples were collected prospectively. Isolates were analyzed by amplified fragment length polymorphism fingerprinting. For species identification, a profile similarity cutoff level of 50% was used, and for strain identification, a cutoff level of 90% was used. Susceptibility for antimicrobial agents was tested by disk diffusion by following the CLSI guideline. The incidences of Acinetobacter isolates ranged from 1.7 to 3.7 per 10,000 patients per year, without a trend of increase, during the study years. Twenty different species were distinguished. Acinetobacter baumannii (27%) and Acinetobacter genomic species (gen. sp.) 3 (26%) were the most prevalent. Other species seen relatively frequently were Acinetobacter lwoffii (11%), Acinetobacter ursingii (4%), Acinetobacter johnsonii (4%), and Acinetobacter junii (3%). One large cluster of A. baumannii, involving 31 patients, and 16 smaller clusters of various species, involving in total 39 patients, with at most 5 patients in 1 cluster, occurred. Overall, 37% of the A. baumannii isolates were fully susceptible to the tested antibiotics. There was a borderline significant (P = 0.059) trend of decreasing susceptibility. A. baumannii was the Acinetobacter species causing the largest burden of multiple-antibiotic resistance and transmissions in the hospital.

The name 'Acinetobacter venetianus' has been used previously to designate three marine hydrocarbon-degrading Acinetobacter strains, of which strain RAG-1 (=ATCC 31012) has industrial applications for the production of the bioemulsifier emulsan. However, to date, the name of this taxon has not been validly published. In this study, five strains were examined to corroborate the delineation of this taxon by means of phenotypic characterization, DNA-DNA hybridization, selective restriction fragment amplification (AFLP), amplified rDNA restriction analysis (ARDRA), rpoB gene sequence analysis and tRNA intergenic spacer length polymorphism analysis (tDNA-PCR) and to emend the description of 'Acinetobacter venetianus' (ex Di Cello et al. 1997). AFLP analysis showed that the five strains formed a tight cluster at 56.8+/-5.0 % genomic relatedness that was separated from strains of other haemolytic species of the genus Acinetobacter and from the type and reference strains of other Acinetobacter species at

Can Escherichia coli be used as an indicator organism for transmission events in hospitals? Perineal and pharyngeal swabs were obtained from patients admitted to a medical or surgical intensive care unit within 24 h of admission and then twice per week. Escherichia coli isolates were typed by random amplification of polymorphic DNA (RAPD) and amplified fragment length polymorphism (AFLP) typing. Based on the typing results, transmission rates for RAPD and AFLP typing were 8.5 and 6.6 per 100 patient-days. Requiring in addition to similarity in genotype parity in time and place for a transmission event, the incidence dropped to 3.8 (RAPD) and 1.7 (AFLP) per 100 patient-days. The two typing methods not only differed with respect to numbers of transmissions identified, but also to individuals involved in transmissions. This study identified a number of problems regarding the use of Escherichia coli as indicator organism for transmission events. The use of Escherichia coli for this purpose cannot be recommended at the moment.

The taxonomic status of 24 haemolytic, non-glucose acidifying Acinetobacter strains that did not belong to any previously described species was investigated by means of a polyphasic approach. Using AFLP fingerprinting, amplified rDNA restriction analysis and phenotypic characterization, the strains were classified into two phenetically coherent groups (comprising 15 and 9 strains) that were distinct from each other and from all known Acinetobacter species. Confirmation that these groups formed two separate lineages within the genus Acinetobacter was obtained from comparative analysis of partial sequences of the gene encoding the beta-subunit of RNA polymerase in all strains and also from 16S rRNA gene sequence analysis of representative strains. Previously published DNA-DNA reassociation data for some of the strains used also supported the species rank for both groups, for which the names Acinetobacter beijerinckii sp. nov. and Acinetobacter gyllenbergii sp. nov. are proposed. The strains of A. beijerinckii sp. nov. originated from human and animal specimens and from various environmental sources, whereas those of A. gyllenbergii sp. nov. were isolated exclusively from human clinical specimens. The phenotypic characteristics most useful for the differentiation of these species from other Acinetobacter species that comprise haemolytic strains were the inability of A. beijerinckii sp. nov. to grow on l-arginine and the ability of A. gyllenbergii sp. nov. to grow on azelate. The type strain of A. beijerinckii sp. nov. is NIPH 838T (=LUH 4759T=CCUG 51249T=CCM 7266T=58aT) and the type strain of A. gyllenbergii sp. nov. is NIPH 2150T (=RUH 422T=CCUG 51248T=CCM 7267T=1271T).

Objectives: The aim of this study was to analyse the emergence of carbapenem resistance among hospital strains of Acinetobacter in the Czech Republic., Methods: Acinetobacter isolates were collected prospectively in 2005-06 from 19 diagnostic laboratories. They were identified to species level by AFLP, typed using AFLP, pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing, and tested for susceptibility to 14 antimicrobials and for the presence of 20 genes associated with antimicrobial resistance., Results: A total of 150 Acinetobacter isolates were obtained from 56 intensive care units of 20 hospitals in 15 cities. They were identified as Acinetobacter baumannii (n = 108) or other species. A. baumannii isolates were allocated to EU clone I (n = 5), EU clone II (n = 66) or other, mostly unique genotypes. Two-thirds of the clone II isolates had nearly identical AFLP and PFGE fingerprints. As many as 85% and 88% isolates were susceptible to meropenem and imipenem (or=8 mg/L were found in 23 A. baumannii isolates, of which 20 belonged to clone II. Isolates with bla(OXA-58-like) (n = 3)(,) bla(OXA-24-like) (n = 1) or ISAba1 adjacent to bla(OXA-51-like) (n = 34) had carbapenem MICs of 2 to >16 mg/L, while those without these elements showed MICs of

Using tDNA-PCR, the type strain CCM 7198T (<--CIP 107470T <--17A04T) of Acinetobacter grimontii was found to be indistinguishable from Acinetobacter junii strains. Therefore, the phenotypic properties, amplified fragment length polymorphism (AFLP) patterns and 16S rRNA and rpoB gene sequences of the type strain of A. grimontii (CCM 7198T) were determined. We found that the strain used l-arginine and l-glutamate, in contrast to the original description and in accordance with the phenotypic properties of A. junii. By AFLP analysis, A. grimontii CCM 7198T clustered at 50.2 % with a set of A. junii strains previously identified by DNA-DNA hybridization, which is in accordance with the previously established intraspecies values of this technique. Sequence similarity of the 16S rRNA gene between the type strains of the two species was found to be 99.9 %. Finally, DNA-DNA relatedness between the type strains of A. junii and A. grimontii was redetermined and was found to be 85 %. These findings were corroborated for a second representative of the A. grimontii type strain, DSM 14968T. These data confirm that Acinetobacter grimontii is a later heterotypic synonym of Acinetobacter junii.

Background: Cross-infection of Pseudomonas aeruginosa has been reported to occur at holiday camps for children with Cystic Fibrosis (CF) with varying frequency. The study aimed to establish the degree of transmission resulting in subsequent infection of P. aeruginosa among CF children (n=80) attending holiday camps in The Netherlands., Methods: The study was performed in the summer of 2001 in four camps organised simultaneously at different locations. Sputum was collected on day 1 of the holiday, and three and six months later. Different morphotypes of P. aeruginosa from sputum were genotyped by AFLP analysis. Criteria were defined for the degree of evidence of transmission., Results: There were 18 cases possible, 2 cases of probable transmission and 1 case of highly probable transmission. Two predominant types of P. aeruginosa were found (types 18 and 23). Type 18 was already prevalent on day 1 mostly in younger children and was involved in eleven cases of transmission; type 23 was involved in six cases of transmission among older children., Conclusions: There was a considerable risk of transmission of P. aeruginosa during holiday camps for CF children in The Netherlands. Two genotypes of P. aeruginosa appeared to be easily transmissible, one of which seemed common in the Dutch CF population.

Objective: To assess the occurrence of the genes of the AdeABC efflux system and their association with antimicrobial resistance in Acinetobacter baumannii., Methods: A set of 116 strains selected for their diversity both in genotypic properties and geographic origin was investigated for the presence of the structural (adeA, adeB and adeC) and regulatory (adeR and adeS) genes of the AdeABC system by PCR, for resistance to 11 antimicrobials by disc diffusion, for MIC of netilmicin and for the presence of aacC2 and aacA4, encoding netilmicin-modifying enzymes., Results: Ninety-five strains were positive for adeA, adeB, adeR and adeS, 10 were positive for 1 to 3 of these genes and 11 were negative for all genes. The adeC gene was found in 49 strains with one or more of the other genes. Forty-one strains were resistant to a maximum of one agent and 75 strains to two or more agents. Netilmicin MICs showed an almost bimodal distribution with respective peaks of 0.5-1 and 8 mg/L; aacC2 or aacA4 was found in six strains with netilmicin MIC of >or=64 mg/L. All 61 strains with netilmicin MICs >or= 4 mg/L were both adeABRS-positive and resistant to two or more agents, whereas netilmicin MICs

An increase in the number of outbreaks of Acinetobacter infection was notified in The Netherlands during 1999-2001. The present study compared the outbreaks at the species and strain levels, and analysed the epidemiology and control measures at the different locations. For each institute, three representative isolates from three patients were identified to the species and strain levels by genotyping methods. A questionnaire investigated the impact of the outbreak, the control measures that were taken, and the possible effects of the measures. Seven outbreaks were associated with Acinetobacter baumannii (three outbreaks with a strain designated strain A, two outbreaks with a strain designated strain B, and one outbreak each with strains designated C and D). An additional outbreak was caused by genomic species 13TU, which is related closely to A. baumannii. Strains B and D were identified as European clones III and II, respectively. Except for two hospitals with outbreaks caused by strain A, there was no known epidemiological link between the participating hospitals. In all hospitals the outbreak occurred on one or several intensive care units, and spread to other departments was noted in two hospitals. The number of patients affected ranged from six to 66 over a period of 2-22 months. In most outbreaks, patients were the likely reservoir from which spread occurred. In all hospitals, a large panel of measures was required to bring the outbreak to an end. Extensive environmental sampling yielded numerous positive samples in most but not all hospitals.

From earlier publications, we noticed that Raman spectra could potentially be used for subspecies identification of microorganisms. Here we evaluated the technique for its use as a typing tool of Acinetobacter species, using a collection of well-characterised strains from five hospital outbreaks. The strains were previously analysed using molecular techniques as cell envelope protein profiling and ribotyping. In this study, we have typed the strains by AFLP analysis and Raman spectroscopy. We compared the results using hierarchical cluster analysis, which showed highly similar groupings by both techniques. There seemed to be some misclassification between two sets of outbreak strains in the Raman analysis. We ascribe this to the clonal relationship between the strains of both outbreaks, described earlier. This results from a highly similar biochemical composition of the strains involved, and hence a highly similar Raman spectrum. We conclude that Raman spectroscopy could be an easy-to-use alternative in epidemiological studies of Acinetobacter strains and a promising starting point for the development of epidemiological studies in general.

In total, 226 individuals from the community were investigated for faecal carriage of Acinetobacter spp. by broth enrichment culture, followed by growth on blood agar and/or Leeds Acinetobacter Medium (LAM). Acinetobacter baumannii was isolated on both LAM and blood agar from one of 100 specimens in the UK and one of 126 specimens in The Netherlands. The predominant species were Acinetobactor johnsonii and genomic sp. 11, which were cultured from 22 and five specimens, respectively. A. baumannii did not seem to be widespread in the faecal flora of individuals in the community.

Two outbreaks of multidrug-resistant Acinetobacter baumannii occurred in our hospital. The outbreak strains were eventually isolated from respiratory ventilators, an apparatus used to cool or warm patients, and four continuous veno-venous hemofiltration machines. Removing dust from the machines and replacing all dust filters brought the outbreaks to an end.

Acinetobacter baumannii isolates collected between 1999 and 2001 from 46 United Kingdom hospitals were compared with previously identified northern European genotypes by amplified-fragment length polymorphism (AFLP) analysis. Two predominant northern European genotypes associated with outbreaks in the mid-1980s had been superseded by new outbreak-associated genotypes.

The taxonomic status of two recently described phenetically distinctive groups within the genus Acinetobacter, designated phenon 1 and phenon 2, was investigated further. The study collection included 51 strains, mainly of clinical origin, from different European countries with properties of either phenon 1 (29 strains) or phenon 2 (22 strains). DNA-DNA hybridization studies and DNA polymorphism analysis by AFLP revealed that these phenons represented two new genomic species. Furthermore, 16S rRNA gene sequence analysis of three representatives of each phenon showed that they formed two distinct lineages within the genus Acinetobacter. The two phenons could be distinguished from each other and from all hitherto-described Acinetobacter (genomic) species by specific phenotypic features and amplified rDNA restriction analysis patterns. The names Acinetobacter ursingii sp. nov. (type strain LUH 3792T = NIPH 137T = LMG 19575T = CNCTC 6735T) and Acinetobacter schindleri sp. nov. (type strain LUH 5832T = NIPH 1034T = LMG 19576T = CNCTC 6736T) are proposed for phenon 1 and phenon 2, respectively. Clinical and epidemiological data indicate that A. ursingii has the capacity to cause bloodstream infections in hospitalized patients.

Bacterial adherence on to several materials with a potential application in reconstructive surgery was studied. Polymer (poly(L-lactide)), composite (hydroxyapatite/poly(L-lactide)) and metal (316L stainless steel) were evaluated both as smooth and sandblasted specimens. All materials were incubated in phosphate-buffered saline, challenged with Staphylococcus aureus or S. epidermidis and evaluated for up to 24 h. S. aureus showed a preference for the metal and composite tested over the polymer used. For S. epidermidis no preference was found for one of the investigated materials. The influence of surface roughness on bacterial growth was demonstrated by increased colonization on the sandblasted specimens.

Using a dilution method (37 degrees C, 42 h), six of ten methicillin-resistant strains of coagulase-negative staphylococci were found to be resistant to cephalothin. Of 20 variations in the method for detection of resistance to methicillin and cephalothin, broth dilution tests at 30 degrees C for 42 h were the most sensitive. Differences are explained by low percentages of cephalothin-resistant clones in methicillin-resistant strains.

Three commercially available test systems for the identification of nonfermentative gram-negative rods were compared: API 20NE, flow N/F and Minitek Nonfermenter System. Two hundred strains were identified by conventional means and by each test system. The rate of correct identification of Acinetobacter, Alcaligenes, Flavobacterium and Moraxella strains to genus level and of the other genera to species level was 92% with API 20NE, 84% with flow N/F and 75% with Minitek Nonfermenter System. The need for these kits in the diagnostic hospital laboratory is also discussed.