Resistentie tegen antimicrobiële middelen van bacteriën voorkomend binnen en buiten het ziekenhuis

In Nederland is tot nu toe geen systematische studie verricht naar het voorkomen van resistentie voor antimicrobiële middelen bij bacterien. Deze informatie is van belang voor bet bepalen van de omvang van de bacteriele resistentie en om een uitspraak te kunnen doen over de bruikbaarheid van de gangbare antimicrobiele middelen. Ziekenhuispatiënten en mensen buiten bet ziekenhuis of de open bevolking zijn in verschillende mate aan deze middelen blootgesteld. Studies over de omvang van de resistentie waren dan ook als regel op deze groepen gericht. Onderzoek buiten het ziekenhuis. Onderzoek naar bacteriële resistentie buiten bet ziekenhuis is ongeveer 10 jaar geleden op verschillende plaatsen verricht. Dit onderzoek was beperkt van omvang. In Borneo werden bij een etnisch geisoleerde bevolking in 19% van 128 faecesmonsters coliformen gevonden die resistent waren voor ampicilline, tetracycline, chlooramfenicol, kanamycine of sulfonamide (Davis e.a. 1970), Onderzoek dat met dezelfde techniek ongeveer gelijktijdig bij westerse bevolkingsgroepen werd uitgevoerd, leverde telkens hogere frequenties van resistente bacteriestammen op (Guinee e.a. 1970, Datta e.a. 1971, Linton e.a. 1972). Patiënten, die in Londen een huisartspraktijk bezochten, waren in 30% van de gevallen drager van E. coli starnmen, die resistent waren voor een of meer van zeven onderzochte antimicrobiele middelen. Deze patiënten gebruikten geen antimicrobiele middelen (Datta e.a. 1971). Ongeveer hetzelfde resultaat werd gevonden in Bristol; alleen bleek daar dat bij kinderen vaker dan bij volwassenen en op het platteland vaker dan in de stad resistente stammen werden aangetroffen (Linton e.a. 1972). Bij kantoorpersoneel in Utrecht werd bij 38% tetracycline-resistente E. coli gevonden (Guin8e e.a. 1970). Resistentie die in deze drie studies voor drie in de huisartspraktijk veel gebruikte middelen werd gevonden, is samengevat in tabel I. Het mechanisme van de resistentie bleek in de meeste gevallen te berusten op de aanwezigheid van overdraagbare resistentie- plasmiden (Falkow 1976, Broda 1979). Met deze studies wordt de oorzaak van bet frequent voorkomen van resistentie niet opgehelderd. Of er sprake is van een toename van resistentie ten gevolge van het gebruik van antimicrobi€le middelen is niet duidelijk, omdat er geen gegevens beschikbaar zijn over de frequentie van resistentie in de periode dat bet gebruik van antimicrobiele middelen nag schaars was. Als mogelijke bron van waaruit grate hoeveelheden resistente stammen de open bevolking kunnen bereiken, wordt de intensieve veehouderij genoemd

Bacillus anthracis-like bacteria and other B. cereus group members in a microbial community within the international space station: a challenge for rapid and easy molecular detection of virulent B. anthracis.

For some microbial species, such as Bacillus anthracis, the etiologic agent of the disease anthrax, correct detection and identification by molecular methods can be problematic. The detection of virulent B. anthracis is challenging due to multiple virulence markers that need to be present in order for B. anthracis to be virulent and its close relationship to Bacillus cereus and other members of the B. cereus group. This is especially the case in environments where build-up of Bacillus spores can occur and several representatives of the B. cereus group may be present, which increases the chance for false-positives. In this study we show the presence of B. anthracis-like bacteria and other members of the B. cereus group in a microbial community within the human environment of the International Space Station and their preliminary identification by using conventional culturing as well as molecular techniques including 16S rDNA sequencing, PCR and real-time PCR. Our study shows that when monitoring the microbial hygiene in a given human environment, health risk assessment is troublesome in the case of virulent B. anthracis, especially if this should be done with rapid, easy to apply and on-site molecular methods

Comparison of two matrix-assisted laser desorption ionisation-time of flight mass spectrometry methods for the identification of clinically relevant anaerobic bacteria

Two commercially available MALDI-TOF MS systems, Bruker MS and Shimadzu MS, were compared for the identification of clinically relevant anaerobic bacteria. A selection of 79 clinical isolates, representing 19 different genera, were tested and compared with identification obtained by 16S rRNA gene sequencing. Correct genus identification was achieved for 71% of isolates by Shimadzu MS and for 61% by Bruker MS. Correct identification at the species level occurred in 61% and 51%, respectively. Shimadzu showed markedly better results for identification of Gram-positive anaerobic cocci. In contrast, the Bruker system performed better than Shimadzu for the Bacteroides fragilis group. When strains not present in the database were excluded from the analyses for each database, both systems performed equally well, with 76.7% and 75.0% correct genus identification for Shimadzu and Bruker, respectively. Similarly, when the most recently updated Bruker database was applied, no difference was observed. We conclude that the composition and quality of the database is crucial for a correct identification. The databases currently available for both systems need to be optimized before MS can be implemented for routine identification of anaerobic bacteria.Molecular basis of bacterial pathogenesis, virulence factors and antibiotic resistanc

Experiences with the Dutch Working Party on antibiotic policy (SWAB).

Item does not contain fulltextThe Dutch Working Party on Antibiotic Policy (Stichting Werkgroep AntibioticaBeleid, SWAB) was founded in 1996 as an initiative of the Society for Infectious Diseases, the Dutch Society for Medical Microbiology, and the Dutch Association of Hospital Pharmacists. Its primary goal is to contribute to the containment of antimicrobial resistance and the expanding costs incurred for the use of antibiotics. SWAB is the Intersectoral Coordinating Mechanism (ICM) for the Netherlands, and it is at present the National Antimicrobial Resistance (AMR) Focal Point. It coordinates the national surveillance of antibiotic resistance, in collaboration with the National Institute for Public Health and the Environment(RIVM), coordinates the surveillance of the use of antibiotics,and runs a guideline development programme. Information about consumption of antimicrobial agents and antimicrobial resistance among medically important bacteria is presented annually in NethMap. Over the past decade, outpatient consumption of antibiotics has risen only slightly, but in the hospital setting there was an overall significant increase in antibiotic use, due mainly to the steady reduction in the average length of patient hospital stays. In 2006 we introduced our electronic national antibiotic guide 'SWAB-ID' for the antibiotic treatment and prophylaxis of common infectious diseases in hospitals

Identificatie van risicopatiënten op grond van patiënt- En ziektekenmerken: Determinanten van ciprofloxacineresistentie

Objective: Primary objective was to identify patient and disease characteristics associated with ciprofloxacin resistance in a university hospital. Secondary objective was to explore the quality of microbial diagnostics in clinical practice. Design: Retrospective nested case control study. Methods: Subsequent individual culture results were linked for 551 internal medicine patients using ciprofloxacin. Cases were patients with a pathogen resistance shift from sensitive before start of ciprofloxacin to resistant after start. Controls were patients with persistent ciprofloxacin sensitive pathogens. Patient (e.g. age, co-morbidity, prior extramural ciprofloxacin use) and disease characteristics (e.g. fever, CRP level) as determinants for ciprofloxacin resistance were assessed. Results: Nearly 80% of the patients were excluded. A shift in resistance was not detectable because there were no culture results after start of ciprofloxacin or because no pathogens were cultured. Of the evaluable patients, 19 were classified as cases and 81 as controls. No patient or disease characteristics were associated with ciprofloxacin resistance although elevated serum creatinin (>130 μmol/L) and CRP (>100 mg/L) levels were more common among the cases. Community patient data of prior ciprofloxacin use and ciprofloxacin resistant pathogens were poorly documented in the hospital files, hindering assessment of these determinants. Conclusion: It is possible to analyse the occurrence of ciprofloxacin resistance and its determinants on a patient level. Due to the nature of routine culture data collection (e.g. no cultures are taken once a patient improves on initiated therapy) this study is limited by the low number of assessable patients. A prospective study with surveillance cultures and a more thorough community patient data collection needs to be conducted to address this limitation