[Prevention of transmission of methicillin-resistant Staphylococcus aureus (MRSA) infection: standard precautions instead of isolation: a 6-year surveillance in a university hospital]. / Prävention von MRSA-Ubertragungen: Standardhygiene statt Isolierung : 6 Jahre Uberwachung in einem Universitätsklinikum.

BACKGROUND: This study was carried out to evaluate whether the risk of acquiring methicillin-resistant Staphylococcus aureus (MRSA) is increased compared to reference data when standard precautions are practiced instead of strict or contact isolation. METHODS: From 2000 through 2005, all patients with MRSA at a university hospital were prospectively surveyed. The isolates were investigated using molecular microbiology methods (PFGE, PCR) and compliance with hand hygiene was indirectly monitored using the consumption of disinfection solutions and glove use as surrogate markers. RESULTS: The MRSA rates of the 797 patients were lower than for the reference data (PEG, KISS), the incidence of MRSA infections was reduced continuously, MRSA transmissions to contact patients could be demonstrated in about 30%, and the consumption of hand disinfection solutions as well as gloves was significantly higher in 2005 compared to 2000. CONCLUSIONS: There is no evidence from our results that practicing standard precautions would increase the risk for the acquisition of MRSA compared to strict or contact isolation.

[Positive screening for MRSA--clinical consequences?]. / Positives MRSA-Screening--klinische Konsequenzen?

BACKGROUND: The worldwide rise of MRSA is equivalent to an increase of nasal colonization with MRSA. The objectives of this study were to investigate the rate of occult nasal MRSA colonization in trauma patients, to elucidate the role of MRSA carriers for endogenous infection (nose --> wound) and to check the efficiency of mupirocin therapy. PATIENTS AND METHODS: A total of 643 consecutive trauma patients underwent MRSA screening (nasal swabs) on admission. At the same time all MRSA wound infections were registered and all isolates were analysed with PFGE (pulsed-field gel electrophoresis) to detect cross-infection between individuals. RESULTS: In 13 patients (2.0%) we found MRSA in the nose and limited isolation as well as therapy with mupirocin were performed. No endogenous transmission of MRSA from the nose to the wound could be seen, and no cross-infection to other patients could be detected. CONCLUSION: Our findings suggest that in our patients with nasal colonization the risk of intra- and interindividual transmission of MRSA is very small. Therefore, in trauma patients screening on admission does not seem to be absolutely necessary either for clinical or for epidemiological reasons.

[Current issues of methicillin-resistant Staphylococcus aureus: epidemiology, diagnostics, prevention, and therapy]. / Aktuelle MRSA-Problematik: Epidemiologie, Diagnostik, Prävention und Therapie.

Methicillin-resistant Staphylococcus aureus (MRSA) play an important role in hospitals today. Internationally and also within individual countries, its frequency differs considerably. Apart from routine microbiological diagnostics, screening at hospital admission is considered to be of great importance, either to introduce infection control measures as recommended by the Robert Koch Institute, or epidemiologically whether a patient was already colonized at admission. Despite the widespread opinion that patients with MRSA must be isolated in single rooms, no scientific data support that measure in the endemic setting. On the other hand, it is broadly accepted that standard infection control practices, predominantly hand disinfection, are clearly the basic requirement for preventing the transmission of pathogens.

Estimation of extra hospital stay attributable to nosocomial infections: heterogeneity and timing of events.

Infections acquired in hospital are likely to affect the duration of hospitalization. Suitable statistical methods for estimating the extra days spent in hospital due to nosocomial infections should allow modeling of the heterogeneity of the patient population and the timing of events, as failure to account for important covariates and failure to model adequately the timing of events may lead to biased results. Three approaches have been used in the past to estimate the extra stay: a comparison of duration of stay of infected and uninfected patients, matching of infected and uninfected patients with respect to potentially important determinants of the length of hospital stay, and matching for time-to-infection in addition to the other factors. While these approaches can allow for the heterogeneity of the patient population, none takes sufficient account of the real timing of events and may overestimate the effect of nosocomial infections. We explored the statistical methods available for analyzing time-to-event data and derived alternative methods to estimate the extra stay that appropriately account for heterogeneity and timing. Data from two prospective cohort studies on postoperative wound infection and on nosocomial pneumonia showed that the two-group comparison yields the highest estimates of extra stay (21 and 14 extra days), while matching for confounders and time reduced the estimates to 11 and 8 extra days; our methods yield even lower results (10-12 and 3-4 extra days).

Aerators as a reservoir of Acinetobacter junii: an outbreak of bacteraemia in paediatric oncology patients.

Tap water can play a role as a source of nosocomial pathogens, and faucet aerators have occasionally been mentioned in the literature associated with colonization or infection in hospitalized patients. In this study, we report on outbreak of bacteraemia in paediatric oncology patients caused by Acinetobacter junii. Environmental sampling showed the water system to be contaminated with A. junii. Molecular typing using automatic laser fluorescence analysis of randomly amplified polymorphic DNA (RAPD-ALFA) revealed two distinct strains. The outbreak strain, isolated from blood cultures of the affected children, was only found in the water taps of staff rooms. Aerators were commonly found to be contaminated, and more so than water obtained after removal of these devices. We believe that conventional aerators consisting of several wire meshes can serve as a reservoir for low levels of bacteria present in the water system. We recommend, especially for high-risk areas, either that aerators should not be used, or the use of aerators consisting of radially and vertically arranged lamellae, which do not lead to the collection of sediment or water stagnation, and to clean them regularly.

Long-lasting contamination of a vitrectomy apparatus with Serratia marcescens.

OBJECTIVE: To investigate the contamination of a vitrectomy apparatus with Serratia marcescens. DESIGN: Descriptive microbiological and molecular environmental study. SETTING: An 1,800-bed university hospital. RESULTS: S. marcescens was found inside the vitrectomy apparatus at the pressure transducer. Molecular typing by randomly amplified polymorphic DNA-automated laser fluorescence analysis and pulsed-field gel electrophoresis identified a single pattern for all strains isolated from the apparatus. Surprisingly, the contaminating strain was identical to two strains of S. marcescens isolated nearly 2 years earlier from two patients who were involved in a small outbreak of acute postoperative endophthalmitis following cataract surgery at another hospital. The emergency vitrectomies in these patients were performed at our hospital with the same apparatus that was found to be contaminated 2 years later. CONCLUSION: Performing a systematic environmental search for the assumed bacterial reservoir within the system of the vitrectomy apparatus finally made it possible to find and eliminate the nidus for the gram-negative rod. Molecular typing demonstrated that all isolates belonged to a single genotype, and revealed unexpectedly a link to two vitrectomies performed 2 years earlier. The data support the hypothesis that the source of the contamination was one of these patients, and thus contamination of the apparatus was present for almost 2 years.

Bacterial contamination of the pressure receiver of a vitrectomy machine.

On a routine sterility check, the authors found bacteria in their vitrectomy machine. Serratia marcescens was detected in the pressure receiver of a roller pump vitrectomy machine. The authors improved the machine by installing a millipore filter in front of the receiver that prevents bacteria from entering it without interfering with the pressure measurements. The origin of Serratia was probably a patient with endophthalmitis who was operated on long before the routine check. Although this appears to be the first report of a bacterial contamination of a vitrectomy machine, the results of testing show that this situation is indeed possible. The authors strongly recommend routine checks of the equipment and suggest mounting an antibacterial filter.

[Microbiological and economic studies of abbreviated procedures for surgical hand disinfection]. / Mikrobiologische und ökonomische Untersuchungen über verkürzte Verfahren für die chirurgische Händedesinfektion.

An investigation was performed of whether shortened procedures for surgical hand disinfection (2 and 3 min, respectively) are equally effective as the usual German standard procedure of 5 min duration and, in addition, which saving of working time and costs would be achievable if shorter procedures were employed. The shortened procedures were: 1) 3 min alcoholic disinfectant (1 min prior handwashing) and 2) 1 min chlorhexidine detergent (Hibiscrub), 2 min 0.5% chlorhexidine in 70% isopropanol (Hibisol). The two shortened procedures were equally effective as the standard procedure (test of equivalence, p < 0.05). The savings of working time and costs calculated for 17708 operations were 1) 2360 h or 79768 German marks and 2) 3540 h or 119652 German marks, respectively.

Prolongation of hospital stay and extra costs due to ventilator-associated pneumonia in an intensive care unit.

A prospective cohort study was performed to determine the prolongation of stay and the extra costs incurred due to the occurrence of ventilator-associated pneumonia in intensive care unit patients. Over a 16-month period a sample of 270 consecutive adult patients from a large university anesthesiological intensive care unit requiring ventilation therapy for more than 24 hours was analyzed. A matching procedure using multiple control patients without pneumonia per infected patient (= case) was employed. Of 78 cases 21 (26.9%) died and were excluded from the matching procedure as well as 23 (29.5%) for whom suitable controls could not be found. The maximum number of controls per case was five. The mean added stay was calculated to be 10.13 days and the extra costs attributable to the prolongation of stay were 14,253 German Marks (US$8,800) per patient, demonstrating considerable added stay and costs due to ventilator-associated pneumonia acquired during intensive care. However, it should be taken into account that the calculations for excess stay and costs are based on a subset of rather ill patients and thus cannot generally apply to all ventilated patients and that cases were excluded which could not be matched.

Added hospital stay due to wound infections following cardiac surgery.

To determine the prolongation of hospital stay due to postoperative wound infections following cardiac surgery, a prospective cohort study was performed by matching multiple control patients without infection to each infected patient (= case). Out of 22 cases, no patient died. No case had to be excluded from the matching process because of a lack of suitable control patients. The maximum number of controls per case was 10. The mean added stay was 12.2 days constituting a considerable prolongation of stay due to wound infection in cardiac surgery.

Use of perioperative antibiotic prophylaxis in selected surgical procedures--results of a survey in 889 surgical departments in German hospitals.

In 1989, a survey on perioperative antibiotic prophylaxis was conducted in 2,739 surgical (general surgical, orthopedic, traumatologic, and cardiothoracic) departments of German hospitals. In all, 889 (32.5%) questionnaries were returned. Regarding the choice of antibiotic and the duration of prophylaxis the respective rates of correct statements were as follows: 32.6% and 55.0% in gastric surgery, 29.5% and 42.9% in colorectal surgery, 38.3% and 50.5% in biliary tract surgery, 81.0% and 41.0% in total hip replacement, 91.3% and 0% in heart valve replacement, and 95.7% and 0% in coronary artery bypass graft. Altogether, the choice of antibiotic and the duration of prophylaxis were correct in only 49.1% and 43.3%, respectively.

[Hygienic and economic significance of sewer drainage in hospitals. Architectural changes in the guidelines of the Federal Health Office]. / Hygienische und ökonomische Bedeutung von Schleusen im Krankenhaus. Die bauliche Umsetzung der Richtlinie des Bundesgesundheitsamtes.

The hygienic importance of barrier zoning in hospitals has been evaluated on the basis of the relevant international literature between 1970 and 1989. There have been only a very few pertinent publications and in none has there been any pointer which would support the hypothesis of barriers having an infection-preventing effect. Using four University Hospitals in Baden-Würtemberg as paradigms, a model was prepared for calculating what space and cost savings were possible, if a simpler system could be installed, instead of the one demanded under federal regulations and already planned for the four hospitals. It was found that it would save a realizable area of 319,5 m2 at a potential cost saving of DM 1,138,335. By dispensing with hygienically not justifiable building work at the planning stage of new hospitals considerable greater costs could be avoided.

Antibiotic usage in community-acquired pneumonia: results of a survey in 288 departments of internal medicine in German hospitals.

In 1989 a survey was conducted in 800 medical departments of university hospitals and large to small teaching and non-teaching hospitals in the Federal Republic of Germany and West Berlin to gather information on the usage of antibiotics for the treatment of community-acquired pneumonia. A total of 288 (36%) questionnaires could be evaluated. In cases of non-life-threatening pneumonia, the therapy specified was mostly correct, although macrolides as the treatment of choice were stated only rarely (11%). However, patients with life-threatening pneumonia were most often (50%) treated with new beta-lactam antibiotics or beta-lactam antibiotics in combination with aminoglycosides (43%). Thus, atypical pathogens causing pneumonia were not covered by most therapeutic regimens.

Potential inroads to reducing hospital-acquired staphylococcal infection and its cost.

Staphylococci are still the most common agents implicated in hospital-acquired infections. In addition to Staphylococcus aureus, coagulase-negative staphylococci have attracted widespread interest, since they have emerged as the most frequent pathogen in foreign-body related infections. The emergence of methicillin-resistant S. aureus has resulted in increasing use of potentially toxic and extremely expensive antibiotics. To prevent hospital-acquired staphylococcal infections only control measures proven to be effective should be implemented and the cost of infection control procedures should always be considered. Handwashing as the simplest, cheapest, and still the most effective measure should constantly be stressed. In this article, effective procedures for the prevention of hospital-acquired staphylococcal infections are summarized, with special emphasis on cost-saving measures.