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Purpose The aim of this study was to assess the feasibility of obtaining nasal and rectal swabs from general practice patients for measuring carriage of antibiotic resistant microorganisms in an area in Rotterdam (the Netherlands) with low socioeconomic status and a large immigrant population. Methods Data collection was from May to December 2017, in one general practice in Rotterdam. We asked adults (≥18 years) visiting the general practitioner (GP) with complaints not related to infections for one nasal and two rectal swabs and tested these for highly resistant microorganisms (HRMOs). Indicators for feasibility were recruitment rate, implementation and acceptation of data collection procedures by the participants. Results We obtained a nasal swab from all included 234 patients and 164 (70%) also gave rectal swabs. On average, 3 out of 30 invited patients (10%) were recruited per day. The GPs considered the workload high to inform and refer to eligible patients for the study and did this inconsistently. Most participants experienced the rectal swab procedure as burdensome and preferred assistance of a medical assistant above self-swabbing. A monetary incentive increased the willingness to provide rectal swabs. Conclusions Obtaining (nasal and) rectal swabs from general practice patients for study purposes proved difficult. Lessons learnt from this feasibility study will help increase participation in HRMO prevalence studies among asymptomatic general practice patients.

Wereldwijd raken steeds meer mensen geinfecteerd door extended-spectrumbetalactamase (ESBL) producerende bacterien. Zagen we ESBL-infecties aanvankelijk vooral in ziekenhuizen, nu krijgen ook huisartsen ermee te maken. Dit komt door de veranderde samenstelling van de (patienten) populatie en doordat ziekenhuiszorg zich verplaatst naar de huisarts. Bij een infectie door een ESBL-producerende bacterie (EPB) kan de standaardbehandeling niet aanslaat. Huisartsen moeten hierop bedacht zijn als een standaardbehandeling bij infecties faalt en risicofactoren voor dragerschap van EPB aanwezig zijn. Samenwerking tussen de eerste en tweede lijn is essentieel voor de aanpak van dit groeiende probleem.

Item does not contain fulltext Objectives: : Residents living in a long-term care facility (LTCF) are more susceptible to infections. Treatment with antimicrobials is sometimes necessary; however, antibiotic use is considered one of the most important drivers of the development of antibiotic resistance. Surveillance data on antibiotic use in these LTCFs are necessary to get more insight into these patterns. The objective of this study was to describe antibiotic use in LTCFs in the Netherlands. Methods: : One hundred and seventy-seven LTCFs in the Netherlands were contacted and asked to participate in a study concerning antibiotic resistance and antibiotic use. Associated pharmacies were asked to provide data about systemic antibiotic use for each participating LTCF location over 1 year. Results on antibiotic use are reported here. Results: : Antibiotic use data from 96 LTCFs were collected from the pharmacies, and 68 of these LTCFs completed additional questionnaires on general characteristics of their location. Mean total use of systemic antimicrobials was 73 DDDs/1000 residents per day (range 2-197 DDDs/1000 residents per day). Co-amoxiclav (23 DDDs/1000 residents/day, range 0-70) was used the most, followed by nitrofurantoin derivatives (12 DDDs/1000 residents/day, range 0-38) and fluoroquinolones (12 DDDs/1000 residents/day, range 0-52). Statistical analysis revealed no significant correlations between the LTCF characteristics and the level of antibiotic use. Conclusions: There was a high use of broad-spectrum antimicrobials, with a large variation in total antibiotic use between individual locations. Further analysis of more in-depth data and possible influencing factors is needed.

Antimicrobial resistance (AMR) is an increasing problem. The prevalence of antimicrobial resistance in general practice patients is expected to be relatively high in Rotterdam, the Dutch city with the largest proportion non-Western immigrants. The aim of this study was to assess the prevalence of antibiotic-resistant uropathogens (Escherichia coli,Klebsiella pneumoniae, andProteus mirabilis) in general practices in Rotterdam, and to find a possible association between the prevalence of antibiotic-resistantE. coliand age, gender, and socioeconomic status (SES). A retrospective analysis was performed of urine samples from general practice patients in 2016. The prevalence of AMR in uropathogens was compared with national resistance data, as was the prevalence of highly and multidrug resistant and extended spectrum β-lactamase (ESBL) producingE. coliandK. pneumoniae.Univariate logistic regression was used to study associations between antibiotic-resistantE. coliand age, gender, and SES area score. No clinically relevant differences were observed in the prevalence of antibiotic-resistant uropathogens in Rotterdam compared with the national prevalence. ForE. coliandK. pneumoniae, the prevalence was 3.6% for ESBL production (both pathogens together), while the prevalence ranged between 4.2%–5.0% for high resistance and between 1.2%–3.3% for multidrug resistance. Ciprofloxacin-resistantE. coliwas significantly associated with higher age. Although Rotterdam has a high percentage of non-western immigrants and a low SES, AMR is low among general practice patients. This indicates that adherence to national guidelines in general practice enables maintenance of low AMR, even in high-risk populations.

Background Exhaled breath analysis is an emerging technology in respiratory disease and infection. Electronic nose devices (e-nose) are small and portable with a potential for point of care application. Ventilator-associated pneumonia (VAP) is a common nosocomial infection occurring in the intensive care unit (ICU). The current best diagnostic approach is based on clinical criteria combined with bronchoalveolar lavage (BAL) and subsequent bacterial culture analysis. BAL is invasive, laborious and time consuming. Exhaled breath analysis by e-nose is non-invasive, easy to perform and could reduce diagnostic time. Aim of this study was to explore whether an e-nose can be used as a non-invasive in vivo diagnostic tool for VAP. Methods Seventy-two patients met the clinical diagnostic criteria of VAP and underwent BAL. In thirty-three patients BAL analysis confirmed the diagnosis of VAP [BAL+(VAP+)], in thirty-nine patients the diagnosis was rejected [BAL−]. Before BAL was performed, exhaled breath was sampled from the expiratory limb of the ventilator into sterile Tedlar bags and subsequently analysed by an e-nose with metal oxide sensors (DiagNose, C-it, Zutphen, The Netherlands). From further fifty-three patients without clinical suspicion of VAP or signs of respiratory disease exhaled breath was collected to serve as a control group [control(VAP−]). The e-nose data from exhaled breath were analysed using logistic regression. Results The ROC curve comparing [BAL+(VAP+)] and [control(VAP−)] patients had an area under the curve (AUC) of 0.82 (95% CI 0.73–0.9). The sensitivity was 88% with a specificity of 66%. The comparison of [BAL+(VAP+)] and [BAL−] patients revealed an AUC of 0.69; 95% CI 0.57–0.81) with a sensitivity of 76% with a specificity of 56%. Conclusion E-nose lacked sensitivity and specificity in the diagnosis of VAP in the present study for current clinical application. Further investigation into this field is warranted to explore the diagnostic possibilities of this promising new technique.

Aim: To determine whether bacteriological analysis of a wound swab is supportive in the clinical assessment of infection of a chronic wound. Methods: Patients attending an outpatient wound clinic who had endured a chronic wound for more than 3 weeks were clinically assessed for infection. In addition, standardized wound swabs were taken according to the Levine technique and the microbiological findings of the swabs compared with the clinical assessment of the wounds. Results: There was no significant relationship between the clinical assessments of the chronic wounds and the qualitative or quantitative bacteriological results of the swabs. Conclusion: Microbiological analysis of wound swabs taken from chronic wounds to support clinical assessment of the wounds is waste of time and money. It may be preferable to assess chronic wounds clinically, however, validation studies of these signs and symptoms are needed.

To understand the dynamics behind the worldwide spread of the mcr-1 gene, we determined the population structure of Escherichia coli and of mobile genetic elements (MGEs) carrying the mcr-1 gene. After a systematic review of the literature we included 65 E. coli whole genome sequences (WGS), adding 6 recently sequenced travel related isolates, and 312 MLST profiles. We included 219 MGEs described in 7 Enterobacteriaceae species isolated from human, animal and environmental samples. Despite a high overall diversity, 2 lineages were observed in the E. coli population that may function as reservoirs of the mcr-1 gene, the largest of which was linked to ST10, a sequence type known for its ubiquity in human faecal samples and in food samples. No genotypic clustering by geographical origin or isolation source was observed. Amongst a total of 13 plasmid incompatibility types, the IncI2, IncX4 and IncHI2 plasmids accounted for more than 90% of MGEs carrying the mcr-1 gene. We observed significant geographical clustering with regional spread of IncHI2 plasmids in Europe and IncI2 in Asia. These findings point towards promiscuous spread of the mcr-1 gene by efficient horizontal gene transfer dominated by a limited number of plasmid incompatibility types.

Den Heijer CDJ, Van Dongen MCJM, Donker GA, Stobberingh EE. Diagnostiek van urineweginfecties bij mannen. Huisarts Wet 2014;57(8):390-4. De diagnostiek van urineweginfecties bij mannen leidt mogelijk tot overbehandeling in de huisartsenpraktijk. Wij formuleerden een beslisregel op basis van een dipsticktest en leeftijd (ouder dan 60 jaar), en gingen na in hoeverre die regel het beleid beinvloedde ten opzichte van de gebruikelijke praktijk. Surveillanceonderzoek binnen de peilstations van NIVEL Zorgregistraties eerste lijn over de periode van januari 2009 tot juli 2011. Via de participerende huisartsen verzamelden wij dipstickresultaten en overige klinische informatie. Bij 103 kolonievormende eenheden per ml urine beschouwden wij de urineweginfectie (UWI) als microbiologisch bevestigd. Wij vergeleken de sensitiviteit en de specificiteit van de beslisregel met die van de gebruikelijke zorg (antibiotica bij een bevestigde urineweginfectie, geen antibiotica bij een niet-bevestigde urineweginfectie). Wij beschikten over de complete gegevens van 490/603 (81%) mannen. Bij 321/490 (66%) werd een UWI bevestigd. De beslisregel adviseert een antibioticum voor te schrijven aan patienten met een positieve nitriettest en aan patienten ouder dan 60 jaar met een positieve leukocytenesterasetest. Bij negatieve testuitslagen was de kans op een UWI 40%, bij mannen jonger dan 60 jaar 29%. De sensitiviteit en de specificiteit van de beslisregel weken niet significant af van die van gebruikelijke zorg: respectievelijk 75% versus 79%, en 70% versus 63% (beide p > 0,05). In de praktijk verbetert de door ons opgestelde beslisregel de diagnostiek van urineweginfecties bij mannen niet. Wanneer er ondanks een negatieve dipstick toch enige verdenking op een urineweginfectie blijft bestaan, volstaat een afwachtend empirisch antibioticumbeleid aangezien de kans op een infectie relatief klein is.

Objectives: To determine the prevalence and genetic background of methicillin-sensitive (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA) obtained from healthy food handlers admitted to the Cantonal Public Health Institute of Zenica, Bosnia and Herzegovina, during 2007-2009. Methods: S. aureus were isolated and identified using standard microbiological methods including coagulase and catalase tests. Antibiotic susceptibility testing by disc diffusion method was performed according to the CLSI guidelines. Methicillin resistance was confirmed by the presence of the mecA gene by PCR. The genetic characterization was performed using spa-typing and BURP algorithm. Results: A total of 189 non-duplicated S. aureus isolates were collected from 13 690 nasal swabs (1.4%), of which three were MRSA (1.6%). Among 173 MSSA analyzed, 66 spa types were clustered into nine spa-CCs, four no founders, and singletons. The MSSA spa-CC015 associated with MLST CC45 was predominant, having 41 (24%) strains. All three MRSA were associated with MLST 152 (spa-CC 355/595) which was not found in MSSA isolates. MRSA-related background had 60% MSSA isolates. There were 127 (71%) MSSA and one MRSA sensitive to all antibiotic tested (the beta-lactam compounds excepted); multi-drug resistance was found in 13 (7.3%) of MSSA. Conclusion: Very low prevalence of S. aureus, as well as MRSA was noted. MSSA were more heterogeneous than MRSA. Although the number of MSSA with a genetic background common to MRSA clones was high, the prevalence of MRSA was low, and MLST CC152 of MRSA was not found among MSSA isolates suggesting that MRSA did not arise from predominant MSSA clones.

To the Editor: The susceptibility to asthma development in childhood is influenced by genetic as well as environmental factors, and interactions between these factors [1–3]. However, at present, their exact role is still largely undetermined. Genetic variations in the innate immune system may lead to different adaptive immune responses to bacteria and may therefore vary the development of asthma [2, 4, 5]. We performed a prospective longitudinal study in preschool children, in which we determined polymorphisms in Toll-like receptors ( TLR s) and CD14 , the presence of bacteria, and the proportion of regulatory T-cells (Treg) all in relation to an asthma diagnosis at 6 years of age. We hypothesise that specific genetic variants in genes that affect the innate immune system influence the response to bacteria and the recruitment of Treg in preschool children, leading to an increased likelihood of asthma at 6 years of age. The Asthma DEtection and Monitoring (ADEM) study is a long-term prospective case–control study. A detailed protocol of this study has previously been published [6]. A total of 202 children who had experienced at least two wheezing episodes during their lifetime (International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire) [7] and 50 children without wheezing episodes were included at 2–4 years of age. The children were randomly selected from a random population sample in Limburg, the Netherlands, based on the presence or absence of recurrent wheeze [6]. During the initial visit, saliva or buccal cells (DNA), nasal and throat swabs (bacterial cultures), and blood (Treg) were collected. Participants were genotyped for six single nucleotide polymorphisms in TLR2 , TLR4 , TLR9 and CD14 (Sequenom …

The aim of this study was to measure the prevalence of (infected) chronic wounds in Dutch nursing homes and to explore which signs and symptoms are used to diagnose infected chronic wounds. Moreover, it was to determine which structural quality indicators related to chronic wound care at ward and institutional levels were fulfilled. In April 2012, as part of the annual National Prevalence Measurement of Care Problems of Maastricht University [Landelijke Prevalentiemeting Zorgproblemen (LPZ)], a multi-center cross-sectional point-prevalence measurement was carried out together with an assessment of relevant care quality indicators. The prevalence was 4·2%; 16 of 72 (22%) chronic wounds were considered to be infected. Increase of exudate (81·3%; n = 13), erythema (68·8%; n = 11), pain (56·3%; n = 9) and wound recalcitrance (56·3%; n = 9) were considered to be diagnostic signs and symptoms of a chronic wound infection. Although at institutional level most quality indicators were fulfilled, at ward level this was not the case. Despite the relatively low number of residents, we consider our population as representative for the nursing home population. It may be an advantage to appoint specific ward nurses and to provide them specifically with knowledge and skills concerning chronic wounds.

The purpose of this study was the evaluation of trends in the antimicrobial resistance of Pseudomonas aeruginosa from intensive care unit (ICU) patients and urology patients in the Netherlands. From 1998 to 2010, 1,927 consecutive P. aeruginosa isolates from ICU (n = 1,393) and urology service patients (n = 534) of 14 university and referral hospitals all over the Netherlands were collected and their susceptibility to relevant antibiotics was determined according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST) guidelines. Over time, a significant upward trend in the resistance of P. aeruginosa strains collected from ICUs to piperacillin (1.2 % to 10.6 %, p = 0.0175), piperacillin-tazobactam (1.2 % to 12.1 %, p = 0.0008), ceftazidime (1.2 % to 7.8 %, p = 0.0064), cefepime (4.8 % to 6.4 %, p = 0.0166), imipenem (6 % to 19.1 %, p

Item does not contain fulltext OBJECTIVES: The objective of this study was to assess carriage of antimicrobial-resistant commensal microorganisms, i.e. Escherichia coli and Staphylococcus aureus, and its predictors in long-term-care facilities (LTCFs). METHODS: Nasal swabs and/or urine or incontinence samples were collected from participating residents in 111 LTCFs and tested for the presence of S. aureus and/or E. coli, respectively. Antimicrobial resistance to eight antimicrobials was linked to antimicrobial usage in the year preceding sampling and to LTCF characteristics. Using multilevel logistic regression, predictors of carriage of ESBL-producing E. coli in LTCFs were identified. RESULTS: S. aureus was identified in 1269/4763 (26.6%) nasal swabs, including 13/4763 (0.3%) MRSA carriers in 9/107 (8%) LTCFs. Of the 5359 urine/incontinence samples, 2934 (55%) yielded E. coli, including 123 (4.2%) producing ESBL, which were found in 53/107 locations (range 1%-33%). For all but one antimicrobial (i.e. nitrofurantoin) >20% of isolated E. coli were resistant. Multilevel multivariable logistic regression identified two predictors of carriage of ESBL-producing E. coli: (i) antimicrobial usage (OR 1.8, 95% CI 1.1-3.0 for each extra 50 DDD/1000 residents/day); and (ii) presence of MRSA carriers in the LTCFs (OR 2.4, 95% CI 1.0-5.6). CONCLUSIONS: The low proportion of 4.2% ESBL-producing E. coli and the low prevalence of 0.3% MRSA carriage found in LTCF residents suggest that Dutch LTCFs are not yet an important reservoir of MDR potential pathogens. Nevertheless, the large variation between LTCFs warrants close monitoring of antimicrobial resistance in LTCFs. Integrated surveillance, i.e. linking data sources on antimicrobial usage, microbiological testing, clinical background data and epidemiological data, is needed.

Objectives: Methicillin-resistant Staphylococcus aureus (MRSA) infections are of worldwide concern. The present study describes the antimicrobial resistance and molecular typing of methicillin-resistant and methicillin-susceptible S. aureus (MSSA) bloodstream isolates in Peru.Methods: Consecutive non-duplicate S. aureus bloodstream isolates were collected over a 15month period (2008-2009) from seven hospitals in Lima and Callao, two contiguous cities in Peru. Detection of mecA gene, spa typing and Staphylococcal Chromosomal Cassette (SCC) mec typing were performed. Antimicrobial resistance was assessed by disk diffusion.Results: Of 338 isolates, MRSA rate was 50.0%. Among MRSA isolates (n = 169), 81.7% were associated to MLST CC5, 68.8% had spa t149/SCCmec I, and more than 85% were co-resistant to ciprofloxacin, clindamycin, erythromycin and gentamicin; 8.9% (n = 15) were associated to MLST CC8, 14 of them had spa t148/SCCmec IV, and more than 70% were co-resistant to ciprofloxacin, clindamycin and erythromycin. Among MSSA isolates (n = 169), there was a higher diversity of spa types (n = 56) compared to MRSA isolates (n = 17), 27.2% were associated to MLST CC8, 23.7% were resistant to erythromycin and clindamycin resistance exceeded 20%.Conclusions: MRSA rate among bloodstream isolates in Peru was 50%, with MLST CC5/t149/SCCmec I representing the most frequent clone. (c) 2012 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

Percutaneous (skin-penetrating) catheters such as central venous catheters (CVCs), are used ubiquitously in the treatment of critically ill patients, although it is known that the risks for serious complications, particularly bloodstream infection and thromboembolism, are high. Materials science and engineering offer important new perspectives regarding further improvement of CVCs. A promising approach is the use of synthetic biocompatible hydrogel coatings with both silver particles and heparin embedded therein. Such formulations combine the well-known broad-spectrum antimicrobial features of silver with the anticoagulant activity of immobilized heparin. Previous work revealed that heparin augments antimicrobial activity of silver, while maintaining its anticoagulant function. This study set out to investigate the synergy of heparin and silver in more detail. Exit-challenge tests, experiments on bacterial killing and adherence, as well as in vitro challenge tests with three Staphylococcus aureus strains (one reference strain, and two clinical isolates) consistently showed the synergistic effect. In addition, the impact of changing the coating's hydrophilicity, and changing the silver concentration in the coatings, were examined. The experimental results, taken together and combined with data from the literature, point out that synergy of heparin and silver is best explained by binding of Ag(+) ions to heparin within the swollen coating, followed by release of heparin-Ag(+) complexes upon immersion of the coatings in an aqueous environment such as blood. Possible implications of this work regarding the development of improved/safer CVCs are briefly discussed.

De verschillende aspecten van recidiverende urineweginfecties bij oudere mannen en vrouwen worden besproken, te weten epidemiologie, pathogenese, symptomatologie, therapie en profylaxe. Waar relevant wordt een vergelijking gemaakt met recidiverende urineweginfecties bij de jongere patient.

Item does not contain fulltext OBJECTIVES: We evaluated the changes in antibiotic resistance from 1998 to 2009 of Klebsiella pneumoniae isolated from the intensive care units (ICUs) and urology services of 14 Dutch hospitals and the consequences for empirical therapy. METHODS: Quantitative antibiotic susceptibility testing of K. pneumoniae was performed in a central laboratory using a microbroth dilution method. Breakpoints were as defined by the European Committee on Antimicrobial Susceptibility Testing (EUCAST). The prevalence of extended-spectrum beta-lactamase (ESBL)- and carbapenemase-producing isolates was determined. RESULTS: A significant increase in resistance among ICU isolates was observed for ceftazidime (4.2%-10.8%), ciprofloxacin (5.8%-18.5%) and trimethoprim/sulfamethoxazole (11.9%-23.1%), and for cefuroxime (2.8%-7.9%) and trimethoprim/sulfamethoxazole (13.5%-27.8%) among urology isolates. Among ICU isolates the prevalence of ESBLs increased significantly from 2% to 8%. Carbapenemase production was not demonstrated. Among ICU isolates the prevalence of multidrug resistance increased and has been >/=12% since 2004. Among urology isolates multidrug resistance was highest in 2009 at 7.4%. Overall, resistance was significantly higher among ICU isolates. CONCLUSIONS: We observed an increase in resistance among ICU and urology isolates and an increased prevalence of ESBLs among ICU isolates. Carbapenemase production was not demonstrated. A regular update of empirical treatment protocols based on actual surveillance data is justified. 01 april 2011

BACKGROUND: The increasing prevalence of uropathogens resistant to antimicrobial agents has stimulated interest in cranberries to prevent recurrent urinary tract infections (UTIs). METHODS: In a double-blind, double-dummy noninferiority trial, 221 premenopausal women with recurrent UTIs were randomized to 12-month prophylaxis use of trimethoprim-sulfamethoxazole (TMP-SMX), 480 mg once daily, or cranberry capsules, 500 mg twice daily. Primary end points were the mean number of symptomatic UTIs over 12 months, the proportion of patients with at least 1 symptomatic UTI, the median time to first UTI, and development of antibiotic resistance in indigenous Escherichia coli. RESULTS: After 12 months, the mean number of patients with at least 1 symptomatic UTI was higher in the cranberry than in the TMP-SMX group (4.0 vs 1.8; P = .02), and the proportion of patients with at least 1 symptomatic UTI was higher in the cranberry than in the TMP-SMX group (78.2% vs 71.1%). Median time to the first symptomatic UTI was 4 months for the cranberry and 8 months for the TMP-SMX group. After 1 month, in the cranberry group, 23.7% of fecal and 28.1% of asymptomatic bacteriuria E coli isolates were TMP-SMX resistant, whereas in the TMP-SMX group, 86.3% of fecal and 90.5% of asymptomatic bacteriuria E coli isolates were TMP-SMX resistant. Similarly, we found increased resistance rates for trimethoprim, amoxicillin, and ciprofloxacin in these E coli isolates after 1 month in the TMP-SMX group. After discontinuation of TMP-SMX, resistance reached baseline levels after 3 months. Antibiotic resistance did not increase in the cranberry group. Cranberries and TMP-SMX were equally well tolerated. CONCLUSION: In premenopausal women, TMP-SMX, 480 mg once daily, is more effective than cranberry capsules, 500 mg twice daily, to prevent recurrent UTIs, at the expense of emerging antibiotic resistance. TRIAL REGISTRATION: isrctn.org Identifier: ISRCTN50717094.

Selective decontamination of the digestive tract (SDD) has been shown to decrease the infection rate and mortality in intensive care units (ICUs); Lactobacillus plantarum 299/299v plus fibre (LAB) has been used for infection prevention and does not harbour the potential disadvantages of antibiotics. The objective was to assess whether LAB is not inferior to SDD in infection prevention.Two hundred fifty-four consecutive ICU patients with expected mechanical ventilation a parts per thousand yen48 h and/or expected ICU stay a parts per thousand yen72 h were assigned to receive SDD: four times daily an oral paste (polymyxin E, gentamicin, amphotericin B), enteral solution (same antibiotics), intravenous cefotaxime (first 4 days) or LAB: two times daily L. plantarum 299/299v with rose-hip.The primary endpoint was infection rate. A difference The trial could not demonstrate the non-inferiority of LAB compared with SDD in infection prevention. Results suggest no increased ICU mortality risk in the LAB group.

Background: To optimize empirical treatment of urinary tract infections (UTIs), regular evaluation of the antibiotic susceptibility of the most common uropathogen, Escherichia coli, is necessary. We compared the antibiotic prescription rate for UTIs in women and E. coli antibiotic susceptibility results, including the prevalence of extended-spectrum beta-lactamase (ESBL) producing strains, in 2009 with data collected 5 years ago. Methods: Urinary samples of female patients with symptoms of uncomplicated UTI in 42 general practices, all participating in the Sentinel Stations network of NIVEL, were collected during a 6-month period. Uropathogens were identified and the antibiotic susceptibility of E. coli was determined. Results: We analysed 970 urine cultures, of which 785 (81%) were considered positive (103 cfu/ml). Escherichia coli accounted for 72% of the isolates. ESBLs showed an increase between both surveys (0.1 versus 1%, P < 0.05), while no difference in antibiotic susceptibility of the commonly used antimicrobial agents for UTIs was observed. A significantly lower susceptibility rate to co-amoxiclav was observed in the eastern region compared with the northern part of the country (80 versus 92%, P < 0.05). Consistent with national guidelines, the prescription rate of trimethoprim decreased over time (19 versus 5%, P < 0.05) whereas nitrofurantoin and fosfomycin rates showed an increase (58 versus 66% and 0 versus 5% respectively, both P < 0.05). Conclusions: The antibiotic susceptibility of uropathogenic E. coli did not change over a 5-year period in female patients with uncomplicated UTI in The Netherlands, but ESBL-prevalence increased. With respect to the prescription of antimicrobial agents a good compliance to national UTI guidelines was observed.

For us to assess the spread of methicillin-resistant Staphylococcus aureus (MRSA), typing of the staphylococcal cassette chromosome mec (SCCmec) is a valuable addition to existing typing methods, such as multilocus sequence typing (MLST). Traditional SCCmec typing assays, that is, that of Oliveira et al. and Ito et al., are polymerase chain reaction (PCR) based, requiring electrophoresis. We introduce a rapid, 2-well, multiplex real-time PCR assay that can be used directly on bacterial suspensions and is able to characterize SCCmec type I to V based on the detection of the ccr genes and the mec complex. The assay was evaluated on 212 clinical MRSA isolates from various countries, associated with MLST clonal complexes (CC) 1, 5, 8, 22, 30, and 45, as well as pig-associated CC398. When comparing the real-time PCR assay with traditional methods, the correct SCCmec element was identified in 209 (99%) of the 212 MRSA isolates. The new assay enables high-throughput analyses for SCCmec on large strain collections.

This study investigated the number and type of chronic wounds actually treated by Dutch nursing home physicians (NHPs). It was also the goal to know how many of the treated chronic wounds they considered infected. The NHPs were asked to choose and rank their top five out of several provided criteria for chronic wound infection. After this, the ranking was compared with the choices an international multidisciplinary Delphi group of wound experts made in 2005. A cross-sectional descriptive survey was conducted using the information from a self-reported questionnaire in a representative sample of Dutch NHPs. About 361 NHPs (25%) were sent a questionnaire. Of the 361 physicians, 139 (38.5%) filled in and returned the questionnaire of which 121 were valid. Of the NHPs, 73.5% actually treated at least one chronic pressure ulcers (PU), whereas 26.5% did not treat any. Of the responding NHPs,31.6 % treated at least one, but never more than two chronic post surgical wounds , whereas 68.4% of the NHPs treated none [corrected]. Chronic venous leg ulcers, arterial ulcers and diabetic ulcers scored infrequently and less than the other two sorts of chronic wounds. Of the Dutch NHPs, 53% considered that none of the PU infected. The other chronic wounds were judged far less frequently to be infected. Dutch NHPs appeared to use more 'traditional' criteria such as 'puss/abscess' and 'malodour' to identify infection and did not change their criteria by wound type. According to this study, NHPs do not frequently see many chronic wounds. The most frequent type of wounds treated was PU. For NHPs, the identification of infection of all types of chronic wounds is difficult. The use of criteria that is not in line with consensus documents may lead to ineffective treatment and even seriously damage patients: the clinical identification of infection is still dependent on experts' opinion. Further research on triggers for the suspicion of wound infection and the development of an evidence-based guideline is necessary.

Item does not contain fulltext BACKGROUND: The increase in incidence of atopic diseases (ADs) in the developed world over the past decades has been associated with reduced exposure of childhood infections. OBJECTIVE: To investigate the relation between early intestinal viral infections in relation to the development of atopic symptoms (eczema, wheeze and atopic sensitization) in the first and second year(s) of life. METHODS: In the KOALA Birth Cohort Study, we assessed IgG seropositivity for rota- and norovirus (GGI.1 and GGII.4) at 1 year of age. This was related to allergic sensitization [specific immunoglobulin E (IgE)] at 1 and 2 years, and parent reported eczema and wheeze in the first 2 years, using logistic regression analysis adjusted for confounders. RESULTS: Rotavirus seropositivity (39%) was associated with an unexpected higher risk of recurrent wheeze in the first and second year of life [adjusted odds ratio (OR) 3.1 and 95% confidence intervals (CI) 1.1-9.1] and persistent and new recurrent wheeze (adjusted OR 2.7 and 95% CI 1.1-6.2). No further associations were found between intestinal viral seropositivity and atopic manifestations. CONCLUSION: Our data did not show a clear protection by enteric viral infections in young children on development of IgE response to allergens, but rotavirus infection in the first year was a risk factor for wheeze. However, this needs to be followed up to older ages in order to establish the true importance of intestinal viral infections and especially cumulative effects in AD aetiology. Exposure to rotavirus may offer a new and interesting focus on infant wheeze and later asthma development.

An increase in antibiotic resistance of Escherichia coli, the most common pathogen in urinary tract infections (UTIs), is encountered worldwide. Optimal treatment of UTIs will contribute substantially to limit antibiotic use and antimicrobial resistance. This study determined trends in antimicrobial resistance of uropathogenic E. coli, which can be of use to optimize UTI guidelines.During 1998-2005, E. coli from urine samples of patients attending urology services were collected in three regions in The Netherlands: north-east (NE, n = 1084), west (W, n = 1064) and south (S, n = 1212). The antibiotic susceptibility was determined using microbroth dilution following CLSI guidelines. E. coli ATCC 35218 and ATCC 25922 were used as reference strains.Amoxicillin resistance remained stable over time (37% to 47%), but was higher in the south (44%) compared with the other regions (40%; P0.02). Resistance to piperacillin increased from 4% (1998) to 32% (2005; P0.001), and resistance to fluoroquinolones increased from 6% to 13% (P0.01). Interregional differences were observed for resistance to piperacillin (NE 10%, W 12%, S 14%; P0.05) and to fluoroquinolones (NE 7%, W 13%, S 8%; P0.001). Trimethoprim +/- sulfamethoxazole resistance remained stable (27% to 37%), as did that of nitrofurantoin (4% to 9%). The percentage of strains with multidrug resistance (resistance to three or more groups of antibiotics) for each region increased over time (P0.05).Antibiotic resistance was fairly constant over time for most agents tested, except for piperacillin and the fluoroquinolones. Regional differences were observed for several compounds. National and regional surveillance of antibiotic resistance is important to keep therapeutic guidelines up-to-date and adequate for the treatment of resistant microorganisms.

Ventilator-associated pneumonia (VAP) is a hospital-acquired infection occurring in the intensive care unit (ICU). The current diagnostic standard is bronchoalveolar lavage (BAL). However, this method is invasive and time-consuming. Analysis of volatile organic compounds (VOCs) in exhaled breath is a non-invasive method that is able to diagnose many pulmonary diseases including COPD and asthma. The aim of this study was to assess the diagnostic potential of exhaled breath to diagnose VAP in ventilated critically ill patients in the ICU. A total of 100 ventilated critically ill patients who were clinically suspected of VAP were included. Using BAL microbial analysis, the clinical suspicion of VAP was confirmed in 32 patients (VAP+) and rejected in 68 patients (VAP-). Prior to the BAL procedure, an exhaled air sample was collected from each patient. The exhaled air samples were measured for the total amount of VOCs by gas chromatography – time of flight – mass spectrometry (GC- tof -MS), and subsequently analysed by multivariate statistics to extract the compounds with the most discriminative power. Statistical comparison revealed that 12 VOCs could correctly classify VAP+ and VAP- with an accuracy of 74.2% ± 4.3 and a sensitivity and specificity of 75.8% ± 5 and 73.0% ± 4.3 respectively. These results suggest that it is possible to determine the presence of VAP in ICU patients by exhaled breath. Such a quick and non-invasive diagnosis of VAP will reduce the disease burden of these patients by earlier diagnosis, but will also reduce the necessity for BAL in the ICU.

A population-based study was conducted among women over the age of 70 years with complaints of uncomplicated urinary tract infections (UTIs). The positive predictive value of the nitrite test alone or in combination with the leukocyte esterase test ranged between 83% and 99%. The nitrofurantoin prescription rate decreased whereas fluoroquinolone and amoxicillin/clavulanic acid prescriptions increased with increasing age. The aetiology of infection was age-dependent. Escherichia coli was the most commonly isolated uropathogen, followed by Proteus mirabilis and Klebsiella pneumoniae. For these uropathogens, the lowest susceptibility percentages were found for amoxicillin, trimethoprim and co-trimoxazole. As trimethoprim susceptibility reached approximately 75%, it may be advisable not to use this as a first-choice agent in the treatment of uncomplicated UTIs in the elderly.

The aim of this study was to determine whether compliance with infection control measures for the care of patients during and after cardiothoracic surgery could be improved by using 'plan-do-study-act' (PDSA) improvement cycles in a 715-bed university hospital. The endpoints of these cycles were indices of correct procedure based on infection control standards. The intervention consisted of instruction and training of nursing and medical staff on the use of PDSA cycles, feedback of the baseline measurements, and the use of posters in the proximity of the operating room (OR). At follow-up, overall compliance only improved in the room used by the perfusionists and the OR. After the follow-up period, monitoring revealed a drop in compliance in the OR, but improved compliance during vascular catheter care of patients with prolonged stay in the intensive care unit (ICU), and during wound care of patients on the nursing ward. The last series of monitoring showed that compliance with general infection control measures in the OR had improved again, and that compliance had remained satisfactory on the ward and in the ICU, with the exception of patients recently transferred to the ICU from the OR. The results show that by using PDSA cycles, compliance with infection control measures can improve significantly. However, repeated monitoring is necessary to ensure continued compliance.

OBJECTIVES: The objectives of this study were (i) to investigate the genetic background of methicillin-resistant Staphylococcus aureus (MRSA) bloodstream isolates from Croatia and (ii) to monitor the prevalence of Panton-Valentine leucocidin (PVL) and toxic shock syndrome toxin-1 (TSST-1) among these isolates.METHODS: Eighty-two hospital-acquired MRSA bloodstream isolates, collected in 2001 and 2002 in Croatia, were characterized by PFGE, staphylococcal cassette chromosome mec (SCCmec) typing and multilocus sequence typing (MLST). The presence of genes encoding PVL and TSST-1 was investigated by real-time PCR.RESULTS: All strains were multiresistant and were distributed among 16 different similarity groups as determined by PFGE. Two of the groups, groups H and K, harboured the majority of the MRSA strains with 52 and 12%, respectively. The predominant SCCmec type found among the isolates was type I (89%). Eleven per cent of the strains harboured a modified SCCmec type III, which contained, in contrast to the regular type III, an additional dcs region. One strain harboured a novel SCCmec type, containing the ccrC gene in combination with the mecI gene, the dcs region, the locus between pI258 and Tn554 (locus E) and the locus between Tn554 and orfX (locus F). MLST showed the presence of ST111-MRSA-I and ST247-MRSA-I among Croatian MRSA isolates. All isolates were negative for both PVL and TSST-1.CONCLUSIONS: These results indicate the emergence of ST111-MRSA-I and ST247-MRSA-I in Croatia among MRSA bloodstream isolates. The virulence factors PVL and TSST-1 were not present among these isolates.

Hopstaken RM, Stobberingh EE, Knottnerus JA, Muris JWM, Nelemans PJ, Rinkens PELM, Dinant GJ. Virale en bacteriele lageluchtweginfecties zijn in de dagelijkse praktijk niet van elkaar te onderscheiden. Huisarts Wet 2005;48(13):660-5.

The prevalence of antibiotic resistant Enterococcus faecalis was determined in fecal samples of 263 patients admitted to the surgical wards of three university-affiliated hospitals on admission, at discharge, and at 1 and 6 months after discharge. A slight increase in the prevalence of antibiotic resistance of E. faecalis was found at discharge for the antibiotics tested compared to those on admission, vancomycin excepted. At 6 months after discharge, the prevalence of resistance for amoxicillin (0%), ciprofloxacin (3%), erythromycin (47%), and oxytetracycline (60%) decreased to the level on admission (respectively 0%, 8%, 45%, and 64%). Gentamicin resistance was the same at discharge (10%) as 1 month later (12%), but decreased 6 months after discharge (8%) to the level on admission (7%). In conclusion, hospitalization resulted in the study population in a slight increase in the prevalence of resistant fecal E. faecalis isolates at discharge, which decreased again (slowly) to the level on admission 6 months after discharge. Thus, the influence of hospitalization on the prevalence of antibiotic resistance in the extramural situation disappears between 1 and 6 months after discharge in this population.

To determine the prevalence of antibiotic-resistant faecal Escherichia coli from adult volunteers from urban (U) areas in Kenya, Mexico, Peru and the Philippines, and non-urban (NU) locations in Curacao, Mexico, Venezuela, Ghana, Zimbabwe and the Philippines.Faecal samples of adult volunteers (n=1290) were analysed in one laboratory for the presence of antimicrobial-resistant E. coli using Eosin Methylene Blue agar plates containing, respectively, ampicillin, oxytetracycline, cefazolin, ciprofloxacin, gentamicin, chloramphenicol and trimethoprim at breakpoint concentrations.The mean age of the volunteers was approximately 35 years; most of them were female. Ciprofloxacin resistance was in the range 1%-63%: the highest percentages were found in the urban populations of Asia and South America. In Peru and the Philippines (U and NU), the prevalence of gentamicin resistance was20%. Cefazolin resistance was the highest in the urban Philippines (25%). Higher prevalences for ampicillin, oxytetracycline and trimethoprim were found for urban areas compared with non-urban ones of Asia, Africa and South America, respectively (P0.05).In the populations studied, antibiotic resistance in faecal E. coli from adult volunteers was emerging for cefazolin, gentamicin and ciprofloxacin and was high for the older drugs ampicillin, oxytetracycline, trimethoprim and chloramphenicol.

To allow rapid identification of Panton-Valentine leukocidin (PVL)-producing Staphylococcus aureus strains, a real-time PCR assay for detection of PVL was developed. This assay is convenient, since it can be applied directly on bacterial suspensions and does not require previous DNA purification. Furthermore, the assay was found to be highly reproducible, robust and specific, since positive results were generated exclusively with PVL-positive S. aureus strains, and neither with PVL-negative strains nor staphylococci other than S. aureus.

The effect of Lactobacillus plantarum 299v on the bacterial composition and metabolic activity in faeces of healthy volunteers: a placebo-controlled study on the onset and duration of effects. Goossens D, Jonkers D, Russel M, Stobberingh E, Van Den Bogaard A, StockbrUgger R. Departments of Gastroenterology and Medical Microbiology, University Hospital Maastricht, Maastricht, The Netherlands. Dominique.Gossens@intmed.unimaas.nl AIM: To study the onset and duration of a possible effect of a fermented oatmeal drink containing Lactobacillus plantarum 299v on the composition of the faecal flora of healthy volunteers in a placebo-controlled, double-blind study. METHODS: Twenty-two participants consumed a fermented oatmeal drink with or without L. plantarum 299v for 4 weeks. Faecal samples were collected weekly: two samples before, four during and four after the consumption of the drink. Several bacterial species were counted and enzyme activities, short-chain fatty acid concentrations, endotoxin concentration and pH were determined. L. plantarum 299v was identified using randomly amplified polymorphic DNA. RESULTS: In contrast with the placebo group, median lactobacilli counts increased significantly from 4.2 (3.4-6.3) to 8.2 (7.3-8.5) log colony-forming units/gram faeces (P = 0.005) after 1 week of consumption of L. plantarum 299v, thereafter remaining stable during the treatment period. One week after cessation, a significant decrease in lactobacilli [to 4.4 (2.2-6.5) log colony-forming units/gram faeces] was observed (P = 0.003). These lactobacilli were identified as L. plantarum 299v. All other bacterial counts, enzyme activities, short-chain fatty acid concentrations, endotoxin concentration and pH remained unchanged. CONCLUSIONS: L. plantarum 299v significantly increased the number of lactobacilli in the faecal flora within 1 week, and this effect disappeared within 1 week after cessation of intake. No other changes in bacterial counts and metabolic products were observed.

Hopstaken RM, Nelemans P, Stobberingh EE, Muris JWM, Rinkens PELM, Dinant GJ. Behandeling van acute lage-luchtweginfecties in de huisartsenpraktijk. Een dubbelblind, gerandomiseerd onderzoek met amoxicilline versus roxitromycine. Huisarts Wet 2003;46(2):73-9. Doelstelling Het beoordelen van de werkzaamheid van roxitromycine versus amoxicilline. Methode In een dubbelblind gerandomiseerd onderzoek is de werkzaamheid van driemaal daags oraal 500 mg amoxicilline vergeleken met die van eenmaal daags oraal 300 mg roxitromycine gedurende 10 dagen. Honderdzesennegentig volwassenen bij wie de huisarts een lage-luchtweginfectie (LLWI) constateerde, en die naar het oordeel van de arts met een antibioticum dienden te worden behandeld, werden geincludeerd. Uitkomstmaten De klinische genezing werd na 10 (primaire uitkomstmaat) en 28 dagen gemeten, waarbij de respons als volgt werd gedefinieerd: afname van LLWI-klachten; volledig ontbreken van LLWI-klachten; afname van afwijkende bevindingen bij lichamelijk onderzoek en volledig ontbreken van afwijkende bevindingen bij lichamelijk onderzoek. De eindconclusie van de huisarts (genezing ja/nee), bacteriologische genezing, het bijwerkingenprofiel en de therapietrouw werden bepaald. Daarnaast werd de tijd vastgesteld tot de klachten verminderden en verdwenen en de tijd tot hervatting van dagelijkse bezigheden, die geheel of gedeeltelijk achterwege waren gebleven op de dagen 1 tot en met 10, 21 en 27. Resultaten De klinische genezingspercentages na voltooiing van de antibioticumkuur (10 dagen) waren voor de 2 groepen niet significant verschillend. Na 28 dagen bleek in de roxitromycinegroep aan de hand van afname van klachten het genezingspercentage niet te zijn toegenomen. Dit significante verschil veranderde echter niets aan de eindconclusie van de huisartsen na afronding van de follow-up: 90% van de patienten was, ongeacht de leeftijd, effectief behandeld met ofwel amoxicilline ofwel roxitromycine. Conclusies De toegevoegde waarde van roxitromycine werd niet bevestigd. Amoxicilline blijft een betrouwbaar antibioticum van eerste keus bij de behandeling van LLWI in de huisartsenpraktijk.

Objective: The impact of hospitalization on the prevalence of resistant Escherichia coli in the intestinal flora of patients admitted to the surgical wards of three Dutch university-affiliated hospitals was analysed prospectively.Methods: Faecal samples were obtained on admission to the hospital, at the time of discharge, and 1 and 6 months after discharge. All samples were examined for resistance to nine antibiotic agents.Results: For the total patient population, no significant differences in the prevalence of resistance were observed at the different sampling intervals, except for a significant decrease in cefazolin resistance between the time of discharge and 6 months after discharge (10% to 3%, PConclusion: In this study, hospitalization did not seem to have any substantial effect on the prevalence of antibiotic-resistant E. coli at the different time intervals. However, as our study population consisted of surgical patients with a relatively moderate antibiotic use, and the prevalence of antibiotic resistance was only analysed for faecal E. coli, further investigation should be encouraged, as the understanding of the interaction between different resistance reservoirs is important for directing future intervention studies.

Background Information on the prevalence of Staphylococcus aureus resistance has mainly been obtained from invasive strains, although the commensal flora is considered an important reservoir of resistance. Within ‘The Appropriateness of prescribing antibiotics in primary health care in Europe with respect to antibiotic resistance’ (APRES) study, we compared the prevalence of nasal S. aureus carriage and antibiotic …

A surgical site infection (SSI) is a serious and costly complication with the highest rates being reported after gastrointestinal surgery. The objective of this cross sectional study was to assess the incidence and risk factors of SSI after gastrointestinal surgery during and after hospitalization, and to evaluate the effect of the VMS (Dutch: “VeiligheidsManagementSysteem”) safety programme on the SSI rate. We assessed the SSI rate from July 2008 until December 2011, according to the criteria of the Centres for Disease Control and Prevention (CDC), before and after implementation of the VMS safety programme which includes a bundle of four interventions. We differentiated between the SSI rate during and after hospitalization and between superficial, deep and organ/ space infections. The incidence of SSI in relation to the wound class, risk factors for SSI, and the compliance with the programme were assessed. Data were obtained during a thirty-day follow-up period after surgery. Surveillance after discharge significantly increased the overall SSI rate. Age higher than fifty years and contaminated or dirty wounds were risk factors for SSIs. Despite increased compliance with the safety programme, no significant decrease in SSI rate was found after implementation. The Dutch VMS safety programme did not show a significant effect on the decrease in incidence of SSI. Surveillance during and after hospitalization is essential for a reliable assessment of the SSI rate.

We investigated the effect of international travel on the gut resistome of 122 healthy travelers from the Netherlands by using a targeted metagenomic approach. Our results confirm high acquisition rates of the extended-spectrum β-lactamase encoding gene blaCTX-M, documenting a rise in prevalence from 9.0% before travel to 33.6% after travel (p

The prevalence and degree of antibiotic resistance of faecal indicator bacteria, Escherichia coli and enteroccoci, were determined in 1321 faecal samples collected from pigs at five abattoirs in The Netherlands and in 100 samples from Swedish pigs. In the Dutch samples a high prevalence of resistance was observed in E. coli for three commonly used antibiotics in pig medicine, amoxycillin (70-94%), oxytetracycline (78-98%) and trimethoprim (62-96%). Also, the prevalence for chloramphenicol (55-67%) and neomycin (38-67%) was relatively high. For the other compounds tested the prevalence was less than 10%. The percentage of samples with a high degree of resistant E. coli showed the same tendency in all Dutch abattoirs although significant differences between the abattoirs were observed. The percentage of Swedish samples with a high degree of resistant E. coli was significantly lower for all antibiotics except nitrofurantoin, gentamicin, flumequin and ciprofloxacin. All enterococci were susceptible to amoxycillin and high-level resistance to gentamicin was observed in 4-6% of the Dutch samples. A high prevalence of resistance and a high degree of resistance was found for erythromycin and oxytetracycline. The prevalence of resistance to dalfopristin-quinupristin ranged from 6 to 8% and for vancomycin from 24 to 46%. Significant differences between the abattoirs were found for all compounds tested except amoxycillin. In the Swedish population both the prevalence and degree of resistance in enterococci were significantly lower except for amoxycillin and gentamicin. This point prevalence study showed that the prevalence and degree of antibiotic resistance in indicator bacteria, E. coli and enterococci, in faecal samples from pigs differed between two countries and reflected differences in antibiotic usage in pigs. To analyse the differences observed between the slaughterhouses, additional information about the farms of origin and antibiotic consumption is necessary.

An inevitable side effect of the use of antibiotics is the emergence and dissemination of resistant bacteria. Most retrospective and prospective studies show that after the introduction of an antibiotic not only the level of resistance of pathogenic bacteria, but also of commensal bacteria increases. Commensal bacteria constitute a reservior of resistance genes for (potentially) pathogenic bacteria. Their level of resistance is considered to be a good indicator for selection pressure by antibiotic use and for resistance problems to be expected in pathogens. Resistant commensal bacteria of food animals might contaminate, like zoonotic bacteria, meat (products) and so reach the intestinal tract of humans. Monitoring the prevalence of resistance in indicator bacteria such as faecal Escherichia coli and enterococci in different populations, animals, patients and healthy humans, makes it feasible to compare the prevalence of resistance and to detect transfer of resistant bacteria or resistance genes from animals to humans and vice versa. Only in countries that use or used avoparcin (a glycopeptide antibiotic, like vancomycin) as antimicrobial growth promoter (AMGP), is vancomycin resistance common in intestinal enterococci, not only in exposed animals, but also in the human population outside hospitals. Resistance genes against antibiotics, that are or have only been used in animals, i.e. nourseothricin, apramycin etc. were found soon after their introduction, not only in animal bacteria but also in the commensal flora of humans, in zoonotic pathogens like salmonellae, but also in strictly human pathogens, like shigellae. This makes it clear that not only clonal spread of resistant strains occurs, but also transfer of resistance genes between human and animal bacteria. Moreover, since the EU ban of avoparcin, a significant decrease has been observed in several European countries in the prevalence of vancomycin resistant enterococci in meat (products), in faecal samples of food animals and healthy humans, which underlines the role of antimicrobial usage in food animals in the selection of bacterial resistance and the transport of these resistances via the food chain to humans. To safeguard public health, the selection and dissemination of resistant bacteria from animals should be controlled. This can only be achieved by reducing the amounts of antibiotics used in animals. Discontinuing the practice of routinely adding AMGP to animal feeds would reduce the amounts of antibiotics used for animals in the EU by a minimum of 30% and in some member states even by 50%.

Colonization with Pseudomonas aeruginosa was studied by taking serial swab specimens from the oropharynges and anuses and tracheal and gastric aspirates from patients in an intensive care unit during a 10-month period in a setting of endemicity. Nineteen (10%) of the 192 patients included in the study were colonized on admission, while another 30 (16%) patients acquired P. aeruginosa while in the hospital. Typing of 353 isolates was performed by random amplified polymorphic DNA (RAPD) analysis, and 56 strains were selected for further typing by RAPD analysis, pulsed-field gel electrophoresis (PFGE), and amplified fragment length polymorphism (AFLP) analysis. By these methods, 42, 44, and 44 genotypes were found, respectively. Computer-aided cluster analysis indicated that similar groups of related isolates were obtained by each method. By taking admission periods into account, analysis of the typing results suggested cross-acquisition of P. aeruginosa for five patient pairs. The small number of transfers and the large number of genotypes found indicate that most P. aeruginosa strains were derived from the patients themselves. The numbers of observed typing patterns and band differences between related isolates were counted for each typing method. AFLP analysis with primers without a selective base proved to be the most discriminatory method, followed by PFGE, AFLP analysis (with one selective base), and RAPD analysis. On the basis of a comparison with established strain differentiation criteria for PFGE, the criteria for differentiation of P. aeruginosa by AFLP analysis are presented.

Vancomycin-resistant enterococci (VRE) were isolated for the first time in 1986 in Europe and in 1987 in the United States. Since then VRE infections have been reported from all over the world. In 1993 enterococci accounted for 12% and VRE accounted for 1% of all hospital infections in the United States (10). In Europe the rate of fecal carriage of VRE in the community is much higher (e.g., 2 to 28%) than that in the United States, where VRE seem to be more or less absent outside hospitals (10, 17). In Europe a diversity of VRE types has also been isolated from sewage, animal waste, meat and meat products, and feces of healthy persons, suggesting a heterogeneous pool of VRE outside hospitals (7, 8, 25, 26). The observation that in the United States VRE have not been isolated from animal sources (6, 10) might be due to the fact that in the United States glycopeptides were never approved for use in animal feeds as antimicrobial performance enhancers (APEs) for growth promotion (28). Until recently, avoparcin, a glycopeptide that shows complete cross-resistance with vancomycin, was commonly used in The Netherlands and in most other countries of the European Union for this purpose (23). The use of avoparcin as an APE has been suggested as a risk factor for carriage of VRE in food animals, as the usage of any antibiotic produces a selective pressure in favor of resistance (5, 12, 26, 27, 29, 34, 39). Therefore, its use as an APE was suspended in the European Union in 1996. Four main types of resistance to glycopeptides have been described: VanA, VanB, VanC, and VanD (4, 18, 30, 31). The vanA gene cluster is the one most commonly found and encodes inducible high-level resistance to both vancomycin and teicoplanin. Dissemination of vancomycin resistance can occur through both clonal expansion of resistant enterococci and horizontal transmission of resistance genes (21, 22). Horizontal transfer of vancomycin resistance is explained by the fact that the genetic determinant for the VanA type of vancomycin resistance typically resides on a mobile DNA element such as Tn1546 (3), which can be transferred to enterococci by plasmids. Recently, in several studies, the heterogeneity of the VanA resistance determinant was described. In those studies, indistinguishable Tn1546-like elements could be found in VRE isolated from farm animals and humans, suggesting transfer of vancomycin resistance elements from farm animals and humans (31, 38, 40). In a previously published report of a study in which the prevalence of VRE in turkeys and farmers was assessed, we found that VRE could be detected in 50% of the fecal samples from turkeys (n = 47) and in 39% of the fecal samples from turkey farmers (n = 47) (33). Furthermore, VRE were isolated from 20% of the fecal samples from turkey slaughterers (n = 48) and 14% of the fecal samples from (sub)urban residents from the same area (n = 117). In addition, an indistinguishable VRE and a vanA-containing element were found in one sample from a turkey and one from a turkey farmer, suggesting animal-to-human transmission of vancomycin resistance as a likely route (33). In the present study we analyzed in more detail the epidemiology of VRE in the context of the influence of avoparcin use in turkey feed. The relative amount of VRE in fecal samples from turkeys and three groups of healthy volunteers with different risks of exposure to fecal bacteria from turkeys, i.e., turkey farmers, turkey slaughterers, and a control group of (sub)urban residents, was determined by calculating the number of VRE relative to the total number of enterococci. The VRE that were isolated were identified and classified with respect to the type of vancomycin resistance. In addition, the antibiotic susceptibilities to several antimicrobial agents of enterococci isolated from vancomycin-free and vancomycin-containing selective agar plates were determined. Possible sharing of VRE between turkeys and humans was assessed by genotyping by pulsed-field gel electrophoresis (PFGE). In addition, the similarity of vancomycin resistance elements found in animal and human isolates was assessed by comparing Tn1546 derivatives of isolates of VRE from turkeys and the three groups of healthy human volunteers. (Parts of this study were presented at the 37th Interscience Conference on Antimicrobial Agents and Chemotherapy, Toronto, Ontario, Canada, 28 September to 1 October 1997.)

For 422 male patients with symptoms indicative of a urinary tract infection, nitrite and leukocyte esterase activity dipstick test results were compared with results of culture of urine samples. The positive predictive value of a positive nitrite test result was 96%. Addition of results of the leukocyte esterase test did not improve the diagnostic accuracy of the nitrite test.

In intensive care units, a large proportion of antibiotics are prescribed for presumed episodes of ventilator-associated pneumonia (VAP). VAP is usually diagnosed on a combination of clinical, radiographic, and microbiologic criteria with a high sensitivity but low specificity for VAP. As a result, patients may receive antibiotics unnecessarily. Specificity can be increased by the addition of quantitative cultures of samples of protected specimen brush (PSB) and bronchoalveolar lavage (BAL) to the diagnostic criteria. We prospectively analyzed the effects of implementation of PSB and BAL in the diagnosis of VAP on antibiotic prescription. PSB and/or BAL were performed in patients who fulfilled the clinical, radiographic, and microbiologic criteria for VAP. Based on quantitative cultures of PSB and/or BAL, patients were categorized into three groups: VAP microbiologically proven (Group 1; n = 72); clinical suspicion of VAP not confirmed microbiologically (Group 2; n = 66); and patients in whom bronchoscopy could not be performed (Group 3; n = 17). In Group 1, antibiotic therapy was instituted empirically in 40 patients (56%) (Group 1a) and after obtaining culture results in the other 32 patients (Group lb). Adjustment of therapy, based on culture results, occurred in 14 (35%) patients in Group la. In Group 2 empiric therapy was instituted in 34 (52%) patients (Group 2a) and dIscontinued within 48 h in 17 of them (50%). In Group 3, 17 (100%) patients were treated with antibiotics. Among the 66 patients in whom a clinical suspicion of VAP was not confirmed, only 18 (27%) were treated with antibiotics, and antibiotic therapy was withheld in 48 (35%) of 138 patients who underwent bronchoscopy. Withholding of antibiotic therapy had no negative effect on the recurrence of a clinical suspicion of VAP or on mortality rates. We conclude that addition of bronchoscopic techniques to the criteria for VAP may help to reduce antibiotic use. However, the definite benefits and cost-effectiveness of these techniques should be analyzed in a randomized study.

When studying the epidemiology of Pseudomonas aeruginosa, determination of the similarity of isolates is crucial. In the present study the distinctive capacity of four phenotyping methods (antibiotic susceptibility patterns, serotyping, phage-typing and outer membrane protein [OMP] profile analysis) was determined and compared to pulsed-field gel electrophoresis (PFGE) of enzyme restricted chromosomal DNA. In all, 91 isolates of P. aeruginosa were cultured from ten patients. Antibiotic susceptibility patterns were concordant for all isolates. Serotyping yielded five, phage-typing eight, OMP profile analysis nine and PFGE seven distinct types of P. aeruginosa. Compared to PFGE, the distinctive capacities were 89% (81/91) for serotyping, 87% (79/91) for phage-typing, and 90% (82/91) for OMP profile analysis. When serotyping results were different, PFGE types also were different (exclusiveness 100%). However, isolates with the same serotype may have various PFGE patterns. In contrast, isolates with similar PFGE patterns could have different phage-types or OMP types. For the study of isolates of P. aeruginosa, serotyping provides a good initial selection to reduce the number of isolates that need to be genotyped.

Department of Gastroenterology, University Hospital Maastricht, University of Limburg, The Netherlands.A reliable diagnosis of Helicobacter pylori is important in clinical practice and research. To evaluate sensitivity, specificity and inter-observer variation of three histological staining methods for the diagnosis of intragastric H. pylori bacterial flora, four observers assessed the presence of H. pylori in a test set of pairs of gastric biopsies taken from 40 patients during GI-endoscopy. Histological slides of one biopsy of each patient (formalin-fixed and paraffin-embedded) were stained with a Modified Giemsa (MG), the Warthin-Starry (WS), and an immunohistochemical method (IMM) using purified polyclonal H. pylori antiserum (DAKO B471). As a standard, bacterial culture was performed on the adjacent biopsy, using the four quadrants method. Special attention was paid to the presence of non-H. pylori bacterial flora. Twenty out of 40 specimens were H. pylori-positive by culture. Using culture as a standard, sensitivity for H. pylori was 90.0+/-10.0% with MG, 70.0+/-14.1% with WS, and 83.8+/-11.1% with IMM stain. Specificity was 53.8+/-19.3%, 82.5+/-9.6% and 90.0+/-0.0%, respectively. Of 37, 14 and eight false positive scores by all observers for MG, WS and IMM, respectively, non-H. pylori flora was cultured from 17, six, and four of the corresponding adjacent biopsies. Non-H. pylori flora may account for overdiagnosis of H. pylori in gastric biopsies. Kappa values for the variance between the four observers were 0.28 for MG, 0.57 for WS, and 0.83 for IMM. Immunohistochemical staining for H. pylori is highly specific and has a low inter-observer variation. We advise that in situations where gastric histology is the main diagnostic tool, IMM should be used for the detection of H. pylori.

Seven laboratories, including a reference laboratory, tested the susceptibility of Moraxella catarrhalis, Streptococcus pneumoniae and Haemophilus influenzae strains to ciprofloxacin, clarithromycin, co-amoxiclav and sparfloxacin with the Etest. A total of 976 strains were collected. The results with ciprofloxacin and sparfloxacin were consistent for all laboratories, while those with clarithromycin and co-amoxiclav were not. The agreement between Etest MICs and broth microdilution was: ciprofloxacin and sparfloxacin, >95%; clarithromycin for all species, 71-85%; co-amoxiclav for H. influenzae, 31%. MIC90 values (broth dilution, mg/L) for M. catarrhalis, S. pneumoniae and H. influenzae were: sparfloxacin, 0.06, 0.5, 0.03; ciprofloxacin, 0.12, 2.0, 0.03; co-amoxiclav, 0.25, 0.25, 0.25; clarithromycin 0.25, 0.25 and 16.