http://repub.eur.nl/res/aut/47585/ List of Publications en http://repub.eur.nl/static-eur/img/logo.png http://repub.eur.nl http://repub.eur.nl/res/pub/36681/ 2007-04-01T00:00:00Z Background. Surgical site infections (SSIs) following total hip arthroplasty can lead to prolonged hospitalization, increased morbidity and mortality, and high costs. This article analyzes the effect of various parameters of surgical antibiotic prophylaxis on the risk of SSI following total hip arthroplasty. Methods. Data about SSI and potential prophylaxis-, patient-, and procedure-related risk factors were prospectively collected for 1922 patients who underwent elective total hip arthroplasty in 11 hospitals that participated in the Dutch intervention project, Surgical Prophylaxis and Surveillance. Multivariate logistic regression analysis was performed to correct for random variation among hospitals. Results. SSIs (superficial and deep) occurred in 50 patients (2.6%). The highest odds ratios for SSI were found in patients who received prophylaxis after incision (2.8, 95% confidence interval [CI], 0.9-8.6; P = .07), had an American Society of Anesthesiology score that was >2 (2.8, 95% CI, 0.8-9.2; P = .09), and experienced a duration of surgery that was >75th percentile (2.5; 95% CI, 1.1-5.8; P = .04). Prolonged prophylaxis after the end of surgery and the use of antibiotic-impregnated cement did not contribute to fewer SSIs in this study. Conclusions. This study suggests that intervention programs in search of amendable factors to prevent SSI should focus on timely administration of antibiotic prophylaxis. http://repub.eur.nl/res/pub/31858/ 1999-12-01T00:00:00Z The rate of change of IS6110 restriction fragment length polymorphism (RFLP) patterns of Mycobacterium tuberculosis was determined in serial isolates from 544 patients. In 25 patients (4.6%), the RFLP patterns of the follow-up isolates differed from the initial isolates. Patients with different follow-up strains were less likely to cluster with patients whose strains had indistinguishable RFLP patterns. Changes in RFLP patterns were more common for persons with extrapulmonary disease and for those who had both pulmonary and extrapulmonary isolates. Based on serial isolates spanning for the most part <3 months, the half-life was extrapolated to be 3.2 years (95% confidence interval, 2.1-5.0). The main implication of this study is that the rate of change of IS6110-based RFLP of M. tuberculosis supports the use of IS6110 typing in epidemiologic studies of recent transmission of tuberculosis.