Propionibacterium acnes in shoulder surgery: is loss of hair protective for infection?

BackgroundPropionibacterium acnes (P acnes) has been linked to chronic infections in shoulder surgery. It was recently observed during first-time shoulder surgery in healthy patients at a rate between 36% and 56%. Male gender and the anterolateral approach were reported risk factors. Because the skin biology greatly differs, we aimed to correlate skin complaints with P acnes–positive intraoperative cultures from different tissue layer samples in patients undergoing shoulder surgery for the first time.MethodsIntraoperative samples (1 skin, 1 superficial, 1 deep tissue, and 1 control sample) from 112 patients (70 men, 42 women; aged 59.2 years) were cultured. The association between the presence of P acnes in the deep or superficial tissue, or both, and 10 items of a validated preoperative questionnaire for skin pathology was explored.ResultsThe cultures were positive for P acnes in 38.4% (n = 43) of the cases. Skin samples were positive for P acnes in 8% (n = 9), superficial samples were positive in 23% (n = 26), and deep samples were positive in 30% (n = 34). Self-reported “loss of hair” was significantly negatively associated with the presence of P acnes in the superficial or deep tissue sample (P = .00028).DiscussionPatients who report having “loss of hair” show fewer P acnes–positive cultures in intraoperative tissue samples taken during open shoulder surgery. Whether this subgroup is at a lesser risk for P acnes infections remains to be substantiated.Level of evidenceBasic Science Study; Microbiology