Outbreak report: a nosocomial outbreak of vancomycin resistant enterococci in a solid organ transplant unit.

Background: Vancomycin resistant enterococci (VRE) are an emerging problem in health care settings. The purpose of the investigation was to assess the extent of the outbreak including environmental contamination and to limit further transmission. Methods: We used retrospective patient and laboratory data including pulse field gel electrophoresis (PFGE) typing and virulence and resistance gene analysis. For comparison of medians the Mann-Whitney and for comparison of proportions the Fisher exact tests were used. Results: PFGE typing of VRE strains of an outbreak of 15 VRE cases in a solid transplant unit revealed that nine of the cases belonged to one identical pattern (A), which was only found twice in the environment. Eleven further positive environmental samples showed a different, but identical PFGE pattern E. Only one patient was infected with this environmental strain.Two of nine (22.2%) PFGE A, but nine of eleven (81.2%) PFGE E samples were positive for gelatinase E (p = 0.01), which is described as enhancing biofilm production, suggesting a survival benefit for this strain on inanimate surfaces. Conclusion: Routine disinfection was not able to stop the cluster, but after repeated enforcement of the infection prevention and control (IPC) bundle such as training, strict adherence to hand hygiene and surface disinfection no further cases were observed. We conclude that certain VRE strains predominate in the environment whereas others predominate in humans. Enforcement of the IPC bundle is essential for controlling VRE outbreaks and reducing further transmission.

Nosocomial outbreak of extensively drug-resistant Pseudomonas aeruginosa associated with aromatherapy.

An increase of extensively drug-resistant Pseudomonas aeruginosa (XDR-PA) in various clinical specimens among intensive care unit patients (n = 7) initiated an outbreak investigation consisting of patient data analyses, control of adherence to infection control guidelines, microbiologic surveys, and molecular-based studies. XDR-PA was detected in a jointly used aroma-oil nursing bottle for aromatherapy. We implemented the restriction of oil sharing among patients. Hence, the outbreak was controlled successfully.

A point prevalence survey on hand hygiene, with a special focus on Candida species.

BACKGROUND: A 1-day point prevalence study evaluated hand hygiene compliance, yeast colonization, and contamination, focusing on the hands of health care workers (HCWs) and patient-oriented surfaces. METHODS: Hand hygiene compliance was evaluated by applying the direct observation technique and the World Health Organization's compliance program, "My Five Moments for Hand Hygiene." A total of 128 samples from HCWs working in intensive care (n = 11) and intermediate care (n = 2) units and 65 environmental samples from Innsbruck Medical University Hospital were investigated. RESULTS: Hand hygiene compliance was superior for nurses (83.5%) and moderate for medical doctors (45.2%). In general, fungal growth was unique; only 9 of 128 HCW samples and only 4 of 65 environmental samples yielded positive results. The genetic relatedness of yeasts from the same species was investigated by random amplified polymorphic DNA (RAPD) typing. RAPD profiles exhibited the potential for cross-transmission of yeasts. CONCLUSION: In general, the fungal colonization and contamination rate was low, but a high level of hand hygiene compliance was lacking.

Activities of antifungal agents against yeasts and filamentous fungi: assessment according to the methodology of the European Committee on Antimicrobial Susceptibility Testing.

We compared the activities of antifungal agents against a wide range of yeasts and filamentous fungi. The methodology of the European Committee on Antimicrobial Susceptibility Testing (EUCAST) for yeasts and spore-forming molds was applied; and a total of 349 clinical isolates of Candida spp., other yeast species, Aspergillus spp., and nondermatophyte non-Aspergillus spp. were investigated. The average geometric mean (GM) of the MICs of the various drugs for Candida spp. were as follows: amphotericin B (AMB), 0.55 microg/ml; liposomal amphotericin B (l-AMB); 0.35 microg/ml; itraconazole (ITC), 0.56 microg/ml; voriconazole (VRC), 0.45 microg/ml; posaconazole (POS), 0.44 microg/ml; and caspofungin (CPF), 0.45 microg/ml. The data indicated that the majority of Candida spp. were susceptible to the traditional and new antifungal drugs. For Aspergillus spp., the average GM MICs of AMB, l-AMB, ITC, VRC, POS, and CPF were 1.49 microg/ml, 1.44 microg/ml, 0.65 microg/ml, 0.34 microg/ml, 0.25 microg/ml, and 0.32 microg/ml, respectively. For the various zygomycetes, the average GM MICs of AMB, l-AMB, ITC, and POS were 1.36 microg/ml, 1.42 microg/ml, 4.37 microg/ml, and 1.65 microg/ml, respectively. Other yeastlike fungi and molds displayed various patterns of susceptibility. In general, the minimal fungicidal concentrations were 1 to 3 dilutions higher than the corresponding MICs. POS, AMB, and l-AMB showed activities against a broader range of fungi than ITC, VRC, and CPF did. Emerging pathogens such as Saccharomyces cerevisiae and Fusarium solani were not killed by any drug. In summary, the EUCAST data showed that the in vitro susceptibilities of yeasts and filamentous fungi are variable, that susceptibility occurs among and within various genera and species, and that susceptibility depends on the antifungal drug tested. AMB, l-AMB, and POS were active against the majority of pathogens, including species that cause rare and difficult-to-treat infections.

Central venous catheter colonization in critically ill patients: a prospective, randomized, controlled study comparing standard with two antiseptic-impregnated catheters.

In this prospective, randomized, controlled, unblinded study, we compared colonization rates of a standard, unimpregnated central venous catheter (CVC) with rates for silver-coated and chlorhexidine-silversulfadiazine (CH-SS)-impregnated CVC. Patient characteristics, CVC insertion site, indwelling time, and colonization detected by semiquantitative and quantitative microbiologic techniques were documented. Two-hundred-seventy-five critically ill patients were included into the study protocol. One-hundred-sixty standard, 160 silver (S)-coated, and 165 externally impregnated CH-SS CVC were inserted. There was a significant difference in CVC colonization rates among study groups (P = 0.029). There was no difference in the colonization rate and the colonization per 1000 catheter days between standard and S-coated (P = 0.564; P = 0.24) or CH-SS-coated CVC (P= 0.795; P = 0.639). When comparing antiseptic CVC with each other, colonization rates were significantly less with CH-SS-impregnated than with S-coated CVC (16.9% versus 7.3%; P = 0.01; 18.2 versus 7.5 of 1000 catheter days; P = 0.003; relative risk, 0.43; 95% confidence interval, 0.21-0.85). Whereas standard and S-coated CVC were first colonized 2 and 3 days after insertion, respectively, CH-SS CVC were first colonized only after 7 days. In conclusion, antiseptic-impregnated CVC could not prevent catheter colonization when compared with standard polyurethane catheters in a critical care setting with infrequent catheter colonization rates and CVC left in place for >10 days.

Early identification of bacteria leading to central venous catheter contamination.

UNLABELLED: Catheter-related bloodstream infections (CRBSI) are a common problem in patients after central venous catheterization. Using DNA analysis we compared bacteria found on the tip of central venous catheters removed because of clinical signs of CRBSI with bacteria found on needle, dilator, and guidewire used for insertion of these catheters. In five of seven central venous catheters removed because of clinical signs of CRBSI, bacteria on the catheter tip were genetically identical to bacteria found on the insertion device, proving that catheter contamination in these cases was caused by contacting bacteria during the initial puncture. These findings may be important for antibiotic prophylaxis or therapy in patients at risk for CRBSI. IMPLICATIONS: In five of seven central venous catheters removed because of clinical signs of catheter-related blood infections, DNA analysis showed bacteria found on the catheter tip to be identical with bacteria found on the puncture kits used for insertion of these catheters.