Efficacy of topical benzoyl peroxide on the reduction of Propionibacterium acnes during shoulder surgery.

BACKGROUND: Propionibacterium acnes infection is a significant problem after shoulder surgery. Residual P. acnes is found on the skin up to 29% of the time immediately after surgical skin preparation and in 70% of dermal biopsy specimens. These residual bacteria may be a source for infection. Identifying more ideal skin preparation may help reduce the risk of infection. The purpose of this study was to evaluate the effect that topical benzoyl peroxide (BPO), with chlorhexidine skin preparation, would have on the presence of P. acnes cultured at the time of shoulder surgery. We hypothesized that adding topical BPO to our skin preparation would reduce the number of positive P. acnes cultures identified during surgery. METHODS: Fifty patients undergoing first-time shoulder surgery were treated with topical 5% BPO cream 48 hours before surgery. After skin preparation, 13 samples per subject were obtained. Cultures were held for 14 days. RESULTS: Fifty patients underwent arthroscopic shoulder surgery; 650 culture specimens were obtained. The skin was positive at the initiation of surgery in 6% of cases. Tissue samples were positive in 6%. The skin was positive in 10% at the end of surgery. None of these rates of positive culture were different from the 4% rate observed with a control swab. CONCLUSION: Application of BPO is an effective way to reduce P. acnes on skin at the beginning and, importantly, at the end of a surgical procedure. This may result in a lower risk for postoperative infection.

Presence of Propionibacterium acnes in primary shoulder arthroscopy: results of aspiration and tissue cultures.

BACKGROUND: Infection after shoulder surgery has a serious impact on patient outcome and costs associated with care. Propionibacterium acnes infection may be insidious and manifest years after index surgery with resultant joint arthropathy or prosthesis infection. Our goal was to evaluate the presence of P. acnes in a group of patients undergoing primary arthroscopic shoulder surgery to better understand this organism. METHODS: Samples were collected from 57 patients undergoing first-time shoulder arthroscopy. Demographic data and medical comorbidities were collected. A control, 2 skin swabs, synovial fluid, and 3 tissue samples were obtained. All samples were placed on aerobic plates, on anaerobic plates, and in thioglycolate broth and held for 28 days. RESULTS: Fifty-seven patients underwent arthroscopic shoulder surgery. The mean age was 51 years. Eighty-one samples (21.8%) were positive for P. acnes when cultures were held 14 days; 32 subjects (56%) had at least 1 culture that grew P. acnes. Positive skin cultures for P. acnes increased from 15.8% before incision to 40.4% at closure. This was even more pronounced in men as positive skin cultures increased from 31.3% before incision to 63.0% at closure. Thirteen patients (22.8%) had more than 3 cultures positive. None of the patients in this study have had signs or symptoms to suggest clinical P. acnes infection. CONCLUSIONS: Of all subjects studied, 56% had at least 1 positive culture; 21% (of all 371 culture specimens obtained) grew P. acnes. We suspect that it is a consequence of true positive cultures from imperfect skin preparation and dermal contamination.

Serum 25-hydroxyvitamin d and the incidence of acute viral respiratory tract infections in healthy adults.

BACKGROUND: Declining serum concentrations of 25-hydroxyvitamin D seen in the fall and winter as distance increases from the equator may be a factor in the seasonal increased prevalence of influenza and other viral infections. This study was done to determine if serum 25-hydroxyvitamin D concentrations correlated with the incidence of acute viral respiratory tract infections. METHODOLOGY/FINDINGS: In this prospective cohort study serial monthly concentrations of 25-hydroxyvitamin D were measured over the fall and winter 2009-2010 in 198 healthy adults, blinded to the nature of the substance being measured. The participants were evaluated for the development of any acute respiratory tract infections by investigators blinded to the 25-hydroxyvitamin D concentrations. The incidence of infection in participants with different concentrations of vitamin D was determined. One hundred ninety-five (98.5%) of the enrolled participants completed the study. Light skin pigmentation, lean body mass, and supplementation with vitamin D were found to correlate with higher concentrations of 25-hydroxyvitamin D. Concentrations of 38 ng/ml or more were associated with a significant (p<0.0001) two-fold reduction in the risk of developing acute respiratory tract infections and with a marked reduction in the percentages of days ill. CONCLUSIONS/SIGNIFICANCE: Maintenance of a 25-hydroxyvitamin D serum concentration of 38 ng/ml or higher should significantly reduce the incidence of acute viral respiratory tract infections and the burden of illness caused thereby, at least during the fall and winter in temperate zones. The findings of the present study provide direction for and call for future interventional studies examining the efficacy of vitamin D supplementation in reducing the incidence and severity of specific viral infections, including influenza, in the general population and in subpopulations with lower 25-hydroxyvitamin D concentrations, such as pregnant women, dark skinned individuals, and the obese.

Pichia ohmeri prosthetic valve endocarditis and review of the literature.

Fungal prosthetic valve endocarditis (PVE) is a serious complication of valve replacement surgery. We report the first case of documented Pichia ohmeri PVE in an immunocompetent man who was successfully treated with valve replacement and antifungal therapy with amphotericin B.