Staphylococcus aureus soft tissue infection may increase the risk of subsequent staphylococcal soft tissue infections

Staphylococcus aureus is the most common cause of soft tissue infections. It is unknown, however, if a patient who has had such an infection is at greater risk for future soft tissue infections with S. aureus

Which Orthopaedic Patients Are Infected with Gram-negative Non-fermenting Rods?

Background : 1st and 2nd generation cephalosporins used for perioperative prophylaxis in orthopaedic surgery do not cover non-fermenting Gram-negative rods (NFR). Methods: Epidemiological cohort study of adult patients operated for orthopedic infections between 2004 and 2014 with perioperative cefuroxim or vancomycin prophylaxis. Exclusion of polyneuropathic ischemic foot infections and septic bursitis cases. Results: Of the total 1840 surgical procedures in the study, 430 grew Gram-negative pathogens (23%), of which 194 (11%) were due to NFR and 143 (8%) to Pseudomonas aeruginosa. Overall, 634 episodes (35%) involved orthopaedic implants (321 arthroplasties, 135 plates, 53 nails, and others). In multivariate analysis and group comparisons, especially preoperative antibiotic use (124/194 vs. 531/1456; p<0.01) was significantly associated with NFR. Conclusions: Overall proportion of NFR oscillated between 9% and 13% among our orthopaedic infections. Variables associated with NFR were antibiotic use prior to hospitalization. The low infection rate of NFR following elective surgery and the community-based epidemiology, has led us to keep our standard perioperative prophylaxis unchanged

Clinical features of anaerobic orthopaedic infections

Some patient populations and types of orthopaedic surgery could be at particular risk for anaerobic infections. In this retrospective cohort study of operated adult patients with infections from 2004 to 2014, we assessed obligate anaerobes and considered first clinical infection episodes. Anaerobes, isolated from intra-operative samples, were identified in 2.4% of 2740 surgical procedures, of which half (33/65; 51%) were anaerobic monomicrobial infections. Propionibacterium acnes, a penicillin and vancomycin susceptible pathogen, was the predominantly isolated anaerobe. By multivariate analysis, the presence of fracture fixation plates was the variable most strongly associated with anaerobic infection (odds ratio: 2.1, 95% CI: 1.3-3.5). Anaerobes were also associated with spondylodesis and polymicrobial infections. In contrast, it revealed less likely in native bone or prosthetic joint infections and was not related to prior antibiotic use. In conclusion, obligate anaerobes in our case series of orthopaedic infections were rare, and mostly encountered in infections related to trauma with open-fracture fixation devices rather than clean surgical site infection. Anaerobes were often co-pathogens, and cultures most frequently recovered P. acnes. These observations thus do not support changes in current practices such as broader anaerobe coverage for perioperative prophylaxis