Risk factors for previously unknown meticillin-resistant Staphylococcus aureus carriage on admission to 13 surgical wards in Europe.

BACKGROUND: Early identification of meticillin-resistant Staphylococcus aureus (MRSA) carriers may be helpful for clinical and epidemiological reasons. AIM: To identify and compare risk factors of previously unknown MRSA carriage on admission to 13 surgical wards in France, Greece, Italy, and Spain. METHODS: The study was a prospective observational cohort study which enrolled consecutive patients screened for MRSA on admission to surgical wards. Sociodemographic data, comorbidities and possible risk factors for MRSA were recorded. A multivariate logistic regression model was used to predict probabilities of previously unknown MRSA colonization on admission based on patient characteristics. Prediction rules for MRSA carriage were developed and evaluated using the c-statistic. FINDINGS: Of 2901 patients enrolled, admission screening identified 111 (3.8%) new MRSA carriers. Independent risk factors for MRSA carriage were urinary catheterization (odds ratio: 4.4; 95% confidence interval: 2.0-9.9), nursing home residency (3.8; 1.9-7.7), chronic skin disease (2.9; 1.5-5.8), wounds/ulcers (2.4; 1.5-4.0), recent hospitalization (2.2; 1.5-3.3), diabetes (1.6, 1.02-2.5), and age >70 years (1.5; 1.03-2.3). However, risk factors varied between centres. The c-statistic for the common prediction rule for all centres was 0.64, indicating limited predictive power. CONCLUSIONS: Risk profiles for MRSA carriers vary between surgical wards in European countries. Identifying local risk factors is important, as a common European prediction rule was found to be of limited clinical value.

[Evaluation of practices involving a cross infection risk in anaesthesia]. / Evaluation des pratiques en anesthésie exposant au risque infectieux par transmission croisée.

OBJECTIVE: The practice of anaesthesiology has the potential for transmitting a number of infectious agents to the patient. In France, several recent cases have been identified, so that a wide survey on anaesthesiology practice has been enhanced. METHODS: An anonymous questionnaire, based on the recommendations of the French Society of Anaesthesiology and Intensive Care (Sfar), was send to 8,771 anaesthesiologists and intensive care practitioners and to 2,070 nurses practicing anaesthesiology. RESULTS: A total of 1,343 questionnaires were analyzed (response rate of 12.4%). The study shows that some recommendations were routinely applied, such as: availability of alcohol-based hand hygiene solution in operating rooms (94%), use of antimicrobial filters for respiratory circuits (99%), use of single-use laryngoscope blades (77%), aseptic technique for central venous catheterization (99%), hand hygiene after contact with body fluids (96%). In contrast, the study showed that some recommendations were partially applied: hand hygiene practice (52%), wear of gloves when a risk of blood exposure exists (23%), cleaning of reusable laryngoscope blades (19%), and incorrect wear of masks (71%). The reuse of the same syringe for several patients was described in 2% of the responses. CONCLUSION: This results, similar to those previously described in the literature, must be followed by appropriate training and education of anaesthesia personnel, implementation of the recommendations, and evaluation of practices. Reuse of the same syringe for several patients have to be eradicated because of the high risk of viral transmission.

[Detection of nasal colonization methicillin-resistant Staphylococcus aureus: a prospective study comparing real-time genic amplification assay vs selective chromogenic media]. / Détection de la colonisation nasale de Staphylococcus aureus résistant à la méthicilline : étude prospective comparant l'amplification génique temps réel vs les milieux chromogènes sélectifs.

UNLABELLED: In contrast to "classical" genic amplification, real-time genic amplification can be performed in every laboratory without the need of sophisticated isolation procedures. Moreover, real-time genic amplification allows an early detection of meticillin resistant Staphylococcus aureus colonization, 2 hours compared to 1 or 2 days for culture. OBJECTIVE: In order to assess the feasibility on Smartcycler of the IDI-MRSA real-time genic amplification assay in comparison with chromogenic media. METHODS: A prospective study has been initiated in July 2004: nasal swabs were taken from patients entering the ICU, vascular surgery, diabetology and geriatry wards. During a 4 months period, 682 specimens have been obtained from 508 patients. RESULTS: Sixty-four (9.3%) patients were positive by genic amplification and selective agar culture (CHROMagar MRSA, MRSASelect and/or ORSAB), 19 (2.9%) were positive by genic amplification only (3 of these patients were under antibiotic treatment); 572 specimens remained negative by both methods. The sensitivity and specificity of this assay were 100% and 96% respectively with a positive predictive value of 70% and negative predictive value of 100%. Initially 82 nasal specimens were unresolved (12%). 38 were resolved following a freeze-thaw cycle. Thus, 44 (6.4%) were unresolved specimens. Comparison between CHROMagar MRSA and MRSASelect showed a good correlation for the detection at 24 hours (5.5% and 5.6% respectively). These two chromogenic media allowed a much better detection of MRSA than ORSAB medium within 24H. CONCLUSION: The results obtained by the early real-time genic amplification for the detection of meticillin resistant Staphylococcus aureus are promising. Despite 6.4% amplification failure, we consider that IDI-MRSA real-time genic amplification assay represents a significant breakthrough in the detection of colonization.

[Audit of preoperative antibiotic prophylaxis in a surgical site infections surveillance network]. / Audit des pratiques de l'antibioprophylaxie chirurgicale dans un réseau de surveillance des infections du site opératoire.

OBJECTIVE: To evaluate the preoperative antibiotic prophylaxis (PAP) prescriptions in a surgical site infection (SSI) surveillance network. STUDY DESIGN: Auto-evaluative audit in a prospective multicenter cohort included in a surveillance system. PATIENTS AND METHODS: Since 1997, surgical wards in volunteer centers monitored all surgery patients each year during a period of two months. Patients were evaluated for SSI during the 30 days following surgery. Participating centers were asked in 2000 to participate to a PAP practice assessment. For each surgery patient, a questionnaire was completed. The "Guidelines for Antibiotic Prophylaxis Prescription in Surgery" edited in 1999 by the Société française d'anesthésie et de réanimation was used as gold standard. RESULTS: 6109 patients were included in the survey from 34 health care centers and 3881 received PAP. 90% of patients received PAP intravenously and 63% received twice the curative dose. PAP was administered within 90 minutes prior to incision in 70% of cases. 78% of PAP lasted less than 24 hours. PAP indication with regards to the type of surgical procedures was assessed in 4629 patients. PAP guidelines were observed in 1573 (34%) patients: 999 patients in whom PAP was not indicated did not receive PAP and 574 received it in compliance with recommended dose and indications. CONCLUSION: Efforts should be made to improve PAP prescription according to standards guidelines.

Antibiotic resistance in nosocomial pulmonary pathogens.

Nosocomial pneumonia is the second most common hospital-acquired infection and are associated with antibiotic-resistant microorganisms. In nosocomial pneumonia, both the diagnosis of the disease and the identification of the pathogen agent are controversial. The lack of standard diagnostic criteria can lead to the inappropriate use of broad-spectrum antibiotic therapy and the emergence of multiresistant bacteria. Moreover, empirical antibiotic treatment must be prescribed after bacteriological sample but before culture results because the majority of nosocomial pneumonias require an urgent antibiotic therapy. Most nosocomial pneumonias are of an endogenous origin, particularly in mechanically ventilated patients, and this is associated with a higher rate of multiresistant methicillin-resistant Staphylococcus aureus, Acinetobacter baumanii, Klebsiella pneumoniae with extended spectrum b-lactamases, and Pseudomonadaceae. Multiple factors influence the frequency of pathogens associated with antibiotic resistance, such as duration of hospital stay, time of onset, prior antibiotic therapy, and local microbial ecology.

[Antibiotic treatment of peritonitis]. / Traitement antibiotique des péritonites.

Secondary peritonitis usually results from perforation of a digestive tract organ. The bacterial contamination depends on the site of the perforation (supra or infra mesocolic) and the clinical setting (community or nosocomial). Although bacteriological specimens have not been proven to be diagnostic in community-acquired peritonitis, they are nevertheless mandatory in the nosocomial setting due to the multiresistant nature of the pathogens. Experimental models have evidenced a biphasic course in peritonitis with microbial synergism between aerobic and anaerobic pathogens. These experimental studies have also evidenced the importance of treating enterobacteria and strict anaerobic pathogens. The treatment of community-acquired peritonitis should be targeted against Gram negative bacilli, strict anaerobic germs and enterococci. Resistant Gram negative bacilli and enterococci are the target bacteria for nosocomial peritonitis. Doses should be adapted to renal function and hemodynamic conditions using antibiotics with proven efficacy on susceptibility tests. The theoretical duration of treatment is a question of debate and should be adapted to each individual case.

[Antibiotic prophylaxis in hepatobiliary surgery]. / Antibioprophylaxie en chirurgie hépatobiliaire.

Today, hepatic and biliary surgery includes conventional biliary surgery, laparoscopic surgery, interventional radiology, endoscopy and hepatic resection surgery. In conventional biliary surgery, the benefit of antibiotic prophylaxis has been demonstrated. Among the risk factors, some are specific (age > 65 years, gallstones in the common bile duct with or without jaundice, history of acute cholecystitis or of biliary surgery) and the others are non specific such as the CDC new index risk (for scoring from 0 to 3, wound infection rates are respectively 1.36, 2.01, 7.11, 11.54%). The targets for antibiotics used in conventional biliary surgery are E. coli, Klebsiella and Streptococcus. In biliary laparoscopic surgery, the rate of infectious complications and results of antibiotic prophylaxis have not been assessed. However, in laparoscopic surgery, the use of an antibiotic prophylaxis similar to that employed in conventional biliary surgery seems logical. In interventional radiology and endoscopy, the modalities and the benefit of antibiotic prophylaxis have not yet been assessed. Infections (angio-cholecystitis) secondary to these procedures are frequent and severe. They are due to multiresistant hospital microorganisms. Antibiotic prophylaxis regimens for hepatic resections have not yet been assessed and are the same as for conventional biliary surgery.