Prophylactic antimicrobials may not be needed to prevent surgical site infection after skin biopsy: a retrospective study

BACKGROUND: Two types of skin biopsies are routinely performed in dermatology: excisional and punch biopsies. A punch biopsy is a relatively low-risk procedure for surgical site infections (SSIs) because of the shallow wound depth and short operative time. In Japan, prophylactic antimicrobial agents are often used after skin biopsies due to lack of consensus, and there is no mention of antimicrobial use after skin biopsies in Japanese guidelines. In this study, we investigated whether prophylactic antibiotic use after punch biopsies reduces the risk of SSI development. METHODS: Cases of punch biopsy performed in our dermatology department during a one-year period from April 2018 to March 2019 were included retrospectively. The cases were divided into a group with and another without prophylactic antimicrobial use after biopsy. RESULTS: A total of 75 cases of punch skin biopsy were reviewed. There were no cases of wound infection after punch biopsy in any of the groups. The number of years of experience of the physicians in the group that used antimicrobials was significantly higher than that in the group that did not use antimicrobials (P < 0.0001). CONCLUSIONS: Our result suggests that the incidence of SSI in punch biopsies without prophylaxis seems to be low. However, further research is needed due to the small number of cases in this study.