Thirteen years of antibiotic susceptibility surveillance of Pseudomonas aeruginosa from intensive care units and urology services in the Netherlands.

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 < 0.0001), meropenem (8.3 % to 17 %, p = 0.0022) and ciprofloxacin (13.1 % to 31.2 %, p = 0.0024) was observed, as was the prevalence of multi-resistance (1.2 % to 8.5 %, p = 0.0002). For P. aeruginosa isolates from the urology services, the resistance to imipenem increased (4.1 % to 7.8 %, p = 0.0006) and to ciprofloxacin it decreased (22.4 % to 18.8 %, p = 0.025). Like in other countries, in the Netherlands, an increase in multi-resistant Gram-negatives is observed, suggesting the presence and dissemination of several mechanisms of resistance. Our findings emphasise the importance of local surveillance for the setting up of local antibiotic guidelines and to support optimal empiric therapy. With the observed increase in multi-resistance, the direct testing of alternative antibiotics like polymyxins and fosfomycin is essential. Our data also illustrate the importance of adequate outbreak control measures.

A 12 year (1998-2009) antibiotic resistance surveillance of Klebsiella pneumoniae collected from intensive care and urology patients in 14 Dutch hospitals.

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 ß-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.

Population structure of Staphylococcus aureus strains isolated from intensive care unit patients in the netherlands over an 11-year period (1996 to 2006).

The genetic background and the presence of several virulence factors of Staphylococcus aureus isolates from intensive care unit (ICU) patients from 14 hospitals in The Netherlands isolated from 1996 until 2006 were investigated. In total, 936 methicillin-susceptible S. aureus (MSSA) and 7 methicillin-resistant S. aureus (MRSA) isolates were collected. The genetic background was determined by spa typing and multilocus sequence typing (MLST). The virulence determinants Panton-Valentine leukocidin (PVL), toxic shock syndrome toxin 1 (TSST-1), and collagen adhesion (CNA) were detected with real-time PCR assays. On the MRSA isolates, mobile resistance staphylococcal cassette chromosome mec (SCCmec) typing was performed. Among the MSSA isolates, 313 different spa types were observed. A genetic background common to MRSA clones, e.g., MLST clonal complex 1 (CC1), CC5, CC8, CC22, CC30, and CC45, was observed among 62% of the isolates. The remaining isolates were associated with MSSA-related MLST CCs. MLST CC1, CC25, and CC30 were continuously present, and other MLST CCs fluctuated over time. Two percent of the MSSA isolates harbored PVL, 21% had TSST-1, and 46% were positive for CNA. There were no changes in the prevalence of the virulence factors over time. Four MRSA isolates were typed as ST8-MRSA-IV (where ST is the MLST sequence type and IV is the SCCmec type), two were ST5-MRSA-II, and one was ST228-MRSA-I. All MRSA isolates were PVL, CNA, and TSST-1 negative except for the two ST5-MRSA-II isolates, which were TSST-1 positive. No changes in the S. aureus genetic background and the prevalence of the virulence factors PVL, CNA, and TSST-1 were observed in ICU patients in The Netherlands over time.

Flucloxacillin, still the empirical choice for putative Staphylococcus aureus infections in intensive care units in the Netherlands.

OBJECTIVES: To determine the usefulness of flucloxacillin as empirical therapy for putative Staphylococcus aureus infections in intensive care unit (ICU) patients in the Netherlands, the antibiotic resistance of S. aureus isolates from ICUs over a 13 year period was investigated. METHODS: From 1996 to 2008, 1146 consecutive S. aureus isolates from ICU patients in 14 large referral hospitals were collected. The susceptibility to relevant antibiotics was determined by microbroth dilution according to CLSI guidelines. RESULTS: Resistance to flucloxacillin was only found in 12 isolates (1%). The resistance to clarithromycin, ciprofloxacin and moxifloxacin showed a significant trend over time, from 4.2% to 10.3%, from 1.0% to approximately 10% and from 0.0% to approximately 5.0%, respectively (P < 0.05). The resistance to penicillin, clindamycin and doxycycline increased over time, from 74% to 75%, from approximately 3.0% in 1996 to 3.2% in 2008 and from 2.2% in 1996 to 8.2% in 2008, respectively (P > 0.05). Resistance to cephalosporins, carbapenems, rifampicin and gentamicin was sporadically observed. No resistance was found to vancomycin, teicoplanin and linezolid. CONCLUSIONS: The empirical choice of flucloxacillin in the case of putative S. aureus infections in patients admitted to ICUs in the Netherlands is still justified.

Antimicrobial resistance in Escherichia coli and Pseudomonas aeruginosa from Intensive Care Units in The Netherlands, 1998-2005.

In 1998, a nationwide surveillance of antibiotic resistance among Escherichia coli and Pseudomonas aeruginosa isolates of patients from 14 Intensive Care Units in The Netherlands was initiated. Minimal inhibitory concentrations (MICs) of broad-spectrum penicillins with and without beta-lactamase inhibitors, cephalosporins, aminoglycosides and fluoroquinolones were determined by a broth microdilution method. An increase in percentages of resistance of E. coli and P. aeruginosa to most antibiotics tested was observed, but rates were still lower than those described in other countries. For E. coli, resistance to amoxicillin was fairly stable at 44% until 2004 and increased to 56% (P=0.01) in 2005. Similarly, piperacillin had a resistance rate of ca. 11% until 2004, which then increased to 38% in 2005 (P<0.001). The MIC distributions of piperacillin and piperacillin/tazobactam for P. aeruginosa were almost identical, as were the resistance rates (4-14%). Resistance to ciprofloxacin nearly doubled in 2005 compared with previous years. Changes in resistance to the antibiotics tested were confirmed by trend analysis. Together with infection control measures, antibiotic resistance surveillance is an important tool to control the antibiotic resistance problem.

Antimicrobial resistance in Gram-negative bacteria from Intensive Care Units and Urology Services. A nationwide study in The Netherlands 1995-2000.

A nationwide 6-year surveillance of resistance in Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis and Pseudomonas aeruginosa from clinical specimens of patients from ten Intensive Care Units and ten Urology Services was started in 1995. MICs of amoxycillin, amoxycillin/clavulanate, trimethoprim, cotrimoxazole, norfloxacin, ciprofloxacin, cefaclor, ceftazidime, imipenem and gentamicin were determined by broth microdilution. Intensive Care Units had higher resistance levels of amoxycillin/clavulanate, cefaclor and ceftazidime (P<0.005) and lower resistance levels of nitrofurantoin, trimethoprim, cotrimoxazole and quinolones (P<0.01) than Urology Services. Changes in MIC distributions in time and development of resistant clusters were observed for nitrofurantoin (E. coli), amoxycillin (E. coli, P. mirabilis), amoxycillin/clavulanate (E. coli) and for quinolones (E. coli). The overall resistance level of ceftazidime and gentamicin was <5%, but this fluctuated with the appearance and disappearance of resistant clones in some Intensive Care Units. Quinolone resistance among P. aeruginosa from Intensive Care Units fluctuated between 7 and 14%.

[Nutrition and health--infections caused by food]. / Voeding en gezondheid--infecties door voedsel.

The annual incidence of food-borne infections in the Netherlands is estimated to be 250,000 or more; registration, however, is lacking. Meat, poultry, milk and eggs are contaminated primarily by intestinal animal commensals (Salmonella, Campylobacter, E. coli O157:H7, Yersinia enterocolitica) or secondarily by animals, humans and the environment during processing (typhoid fever, Shigella, Listeria, Clostridium, hepatitis A virus, Norwalk virus, parasites). The guidelines for the prevention of contamination are insufficient. Intensity of production and the economic importance of fast, large-scale production are given priority over food safety. Information fails to reach the consumer.

An audit of microbiology laboratory utilization: the diagnosis of infection in orthopedic surgery.

OBJECTIVE: To analyse the quality of ordering, collection and transport of specimens for microbiological analysis by a department of orthopedic surgery. METHODS: The analysis consisted of a prospective formal evaluation performed by two consultant microbiologists. RESULTS: One hundred and seventeen consecutive requests were audited. These requests belonged to 55 clinical episodes, 39 of which were of (presumed) infection and 16 of surveillance. The main sites sampled were: joint 28 (51%), and extra-articular bone or tissue 6 (11%). Of 98 surgical specimens, 20 (20%) yielded a relevant microorganism. The requests were classified as definitely appropriate in 67% and 85% of episodes, by the two consultants respectively. No request was considered unjustified. Collection, handling and transport were categorized as definitely appropriate in 56% and 73% of requests. Analysis of compliance with an existing protocol for prosthetic joint revision revealed similar errors. CONCLUSION: Audits of this type can give invaluable information about the area of uncertainty between the clinician and the laboratory and can identify appropriate measures for corrective action.