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J G Koeleman

Publications and source records attributed to J G Koeleman.

13 recordsLinked to original sources
PubMed2001

Antibiotic resistance is a major risk factor for epidemic behavior of Acinetobacter baumannii.

OBJECTIVE: To study the presence of bacterial factors in clinical isolates of Acinetobacter species in order to identify markers of epidemic potential. DESIGN: Case-control study. METHODS: Forty-six isolates of Acinetobacter species, including 23 epidemic and 23 sporadic strains from different outbreaks in nine European countries, were compared for the presence of the following factors: hemagglutination, presence of capsules and fimbriae, binding to salivary mucins, resistance to drying, and antibiogram typing. Genotyping of all strains was performed by amplified fragment-length polymorphism (AFLP). RESULTS: All outbreak strains except two (91%) were identified as Acinetobacter baumannii. Binding to salivary mucins and resistance to antibiotics were significantly associated with epidemic behavior. Antibiogram typing showed clustering of predominantly A baumannii strains within one group, and these strains were significantly more resistant to antibiotics than sporadic strains. AFLP genotyping revealed a great heterogeneity among the different European Acinetobacter strains. Cluster analysis of AFLP fingerprints showed several small clusters of different A baumannii outbreak strains. AFLP genotyping could not identify a common epidemic marker within the strains studied. CONCLUSIONS: Antibiogram typing can be used in routine clinical laboratories as a screening method to recognize potentially epidemic A baumannii strains. Several other factors were found, both in different outbreaks as well as in sporadic Acinetobacter isolates. These characteristics were unable to predict epidemic behavior and therefore cannot be used as discriminative epidemic markers. AFLP genotyping demonstrated no common clonal origin of European epidemic A baumannii strains. This indicates that any clinical A baumannii isolate with resistance to multiple antibiotics can be a potential nosocomial outbreak strain.

Acinetobacter↗
PubMed2001

Identification of epidemic strains of Acinetobacter baumannii by integrase gene PCR.

Forty-eight clinical Acinetobacter isolates with different epidemic behavior were investigated for the presence of integrons and plasmids and for antibiotic susceptibility. Integrons were demonstrated in 50% of the strains by an integrase gene PCR. Epidemic strains of Acinetobacter baumannii were found to contain significantly more integrons than nonepidemic strains. Also, the presence of integrons was significantly correlated with simultaneous resistance to several antibiotics. Plasmids were detected in 42% of the strains. However, there was no significant correlation between the numbers of plasmids and integrons in Acinetobacter species strains, no significant difference in the number of plasmids between epidemic and nonepidemic A. baumannii strains, and no significant correlation between the presence of plasmids and antibiotic resistance. Hence, it is likely that integrons play an important role in antibiotic resistance and thereby in the epidemic behavior of A. baumannii. Because the integrase gene PCR identified almost three-quarters of the epidemic A. baumannii isolates (17 of 23), this seems to be a rapid and simple technique for the routine screening and identification of clinical A. baumannii isolates with epidemic potential.

Acinetobacter↗
PubMed2000

Prevalence and determinants of fecal colonization with vancomycin-resistant Enterococcus in hospitalized patients in The Netherlands.

OBJECTIVE: To determine the prevalence and determinants of fecal carriage of vancomycin-resistant enterococci (VRE) in intensive care unit (ICU), hematology-oncology, and hemodialysis patients in The Netherlands. DESIGN: Descriptive, multicenter study, with yearly 1-week point-prevalence assessments between 1995 and 1998. POPULATION: All patients hospitalized on the testing days in ICUs and hematology-oncology wards in nine hospitals in The Netherlands were included. METHODS: Rectal swabs obtained from 1,112 patients were screened for enterococci in a selective broth and subcultured on selective media with and without 6 mg/L vancomycin. Resistance genotypes were determined by polymerase chain reaction. Further characterization of VRE strains was done by pulsed-field gel electrophoresis (PFGE). We studied possible determinants of VRE colonization with a logistic regression analysis model. Determinants analyzed included gender, age, and log-transformed length of prior hospital stay. RESULTS: The results showed that 614 (55%) of 1,112 patients were colonized with vancomycin-sensitive enterococci, and 15 (1.4%) of 1,112 carried VRE. No increase in VRE colonization was observed from 1995 to 1998. Eleven strains were identified as Enterococcus faecium and four as Enterococcus faecalis. All E faecium and one E faecalis carried the vanA gene; the other E faecalis strains harbored the vanB gene. PFGE revealed that three vanB VRE isolated from patients hospitalized in one single ICU were related, suggesting nosocomial transmission. Though higher age seemed associated with VRE colonization, exclusion of patients with the nosocomial strain from the regression analysis decreased this relation to nonsignificant. Duration of hospital stay was not associated with VRE colonization. CONCLUSION: VRE colonization in Dutch hospitals is an infrequent phenomenon. Although nosocomial spread occurs, most observed cases were unrelated, which suggests the possibility of VRE acquisition from outside the hospital. Prolonged hospital stay, age, and gender proved unrelated to VRE colonization.

Adolescent↗
PubMed1999

Nosocomial outbreak of gentamicin-resistant Klebsiella pneumoniae in a neonatal intensive care unit controlled by a change in antibiotic policy.

Between August and November 1997, a nosocomial outbreak caused by gentamicin-resistant Klebsiella pneumoniae occurred in the Neonatal Intensive Care Unit (NICU) of our hospital. Thirteen neonates became colonized and three of them became infected. Comparison of the isolates by amplified fragment length polymorphism (AFLP) revealed clonal similarity for isolates of eight neonates (homology > 90%). Cultures from environmental specimens were negative for gentamicin-resistant K. pneumoniae. A case-control study was conducted to identify risk factors associated with acquisition of gentamicin-resistant K. pneumoniae. Risk factors were low gestational age and birth weight. These neonates need more care and handling and may therefore, be more at risk of colonization. Length of stay on the NICU was significantly longer for cases, but mean time until colonization (6.3 days) was shorter than the total stay for controls (9.5 days). No single member of the medical or nursing staff was significantly more involved with cases than with controls. The outbreak was stopped by replacing gentamicin by amikacin as the antibiotic of first choice whenever the use of an aminoglycoside antibiotic was indicated.

Amikacin↗
PubMed1998

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.

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.

Acinetobacter↗
PubMed1997

Nosocomial outbreak of multi-resistant Acinetobacter baumannii on a surgical ward: epidemiology and risk factors for acquisition.

Between December 1994 and April 1995, a nosocomial outbreak caused by a multi-resistant Acinetobacter baumannii, occurred on a surgical ward in our hospital. The organism was isolated from 13 patients, eight of whom were infected whereas the others were colonized. Twelve isolates were compared by cell envelope protein electrophoretic profiles and AFLP, a recently described DNA fingerprinting method. Both methods indicated that this outbreak was caused by spread of a single strain, which was identified as A. baumannii by amplified ribosomal DNA fingerprinting (ARDRA). A case-control comparison was performed to identify risk factors associated with nosocomial acquisition of A. baumannii. Risk factors for cross-colonization were length of stay, surgery, wounds and treatment with broad-spectrum antibiotics. Cross-infection with A. baumannii among patients occurred despite implementation of stringent infection control measures. The outbreak was controlled after temporary closure of the surgical ward for disinfection purposes. Patients admitted on a general surgical ward colonized or infected with multi-resistant A. baumannii strains should alert the hospital infection control team, and prompt implementation of strict infection prevention measures to prevent further spread is advised.

Acinetobacter↗
PubMed1997

Fecal carriage of vancomycin-resistant enterococci in hospitalized patients and those living in the community in The Netherlands.

In order to determine the prevalence of vancomycin-resistant enterococci (VRE) in The Netherlands, 624 hospitalized patients from intensive care units or hemato-oncology wards in nine hospitals and 200 patients living in the community were screened for VRE colonization. Enterococci were found in 49% of the hospitalized patients and in 80% of the patients living in the community. Of these strains, 43 and 32%, respectively, were Enterococcus faecium. VRE were isolated from 12 of 624 (2%) and 4 of 200 (2%) hospitalized patients and patients living in the community, respectively. PCR analysis of these 16 strains and 11 additional clinical VRE isolates from one of the participating hospitals revealed 24 vanA gene-containing, 1 vanB gene-containing, and 2 vanC1 gene-containing strains. All strains were cross-resistant to avoparcin but were sensitive to the novel glycopeptide antibiotic LY333328. Genotyping of the strains by arbitrarily primed PCR and pulsed-field gel electrophoresis revealed a high degree of genetic heterogeneity. This underscores a lack of hospital-driven endemicity of VRE clones. It is suggested that the VRE in hospitalized patients have originated from unknown sources in the community.

Anti-Bacterial Agents↗
PubMed1996

Occurrence of yeast bloodstream infections between 1987 and 1995 in five Dutch university hospitals.

The aim of this study was to identify retrospectively trends in fungal bloodstream infections in The Netherlands in the period from 1987 to 1995. Results of over 395,000 blood cultures from five Dutch university hospitals were evaluated. Overall, there were more than 12 million patient days of care during the nine-year study period. The rate of candidemia doubled in the study period, reaching an incidence of 0.71 episodes per 10,000 patient days in 1995. The general increase in candidemia was paralleled by an increase in non-Candida albicans bloodstream infections, mainly due to Candida glabrata. However, more than 60% of the infections were caused by Candida albicans. Fluconazole-resistant species such as Candida krusei did not emerge during the study period. The increasing rate of candidemia found in Dutch university hospitals is similar to the trend observed in the USA, but the rate is lower and the increase is less pronounced.

Antifungal Agents↗
PubMed1994

[Exogenous reinfection with Mycobacterium tuberculosis caused by nosocomial transmission by a patient with AIDS].

A 55-year-old AIDS patient relapsed with tuberculosis as a result of exogenous reinfection, 1.5 years after a prior diagnosis of tuberculosis, for which he had been treated. He was reinfected after exposure to another AIDS patient, a 25-year-old man with tuberculosis, when they were hospitalized together during 5 days. The diagnosis of tuberculosis in the latter patient was delayed because the clinical picture was obscured by another infection. Reinfection and nosocomial transmission were demonstrated by analysis of the restriction-fragment-length polymorphism patterns on serial isolates of Mycobacterium tuberculosis. Increased alertness to tuberculosis, especially among HIV-infected persons, and implementation of effective infection control precautions are important in the prevention of nosocomial transmission.

AIDS-Related Opportunistic Infections↗
PubMed1992

Retrospective study to determine the diagnostic value of the Widal test in a non-endemic country.

The purpose of this study was to determine the usefulness of the Widal test in the diagnosis of typhoid fever. Data were obtained by retrospective analysis of 311 Widal requests covering a six-year period. Nine cases of typhoid infection were diagnosed culturally. Of these, only three patients had samples for serological examination, all giving indicative titres. Of the 274 evaluated sera, 26 showed significant agglutinating titres; 23 of them were false positive. These results show that routine use of the Widal test is of limited value and should only be used for patients in whom repeated cultures remain negative.

Agglutination Tests↗
PubMed1990

Cryptococcal meningo-encephalitis after prolonged corticosteroid therapy.

We present a case of a 69-yr-old woman who developed cryptococcal meningo-encephalitis after 9 yr of corticosteroid therapy. The diagnosis was made on an India ink preparation and positive culture of the cerebrospinal fluid sediment. NMR-imaging was a useful tool for detecting intracerebral localisation of the infection. The patient was successfully treated with amphotericin B and flucytosine for 6 wk and with itraconazole for another 8 wk.

Aged↗