Surgical site infections in thyroid and parathyroid surgery in Japan: An analysis of the Japan Nosocomial Infections Surveillance database from 2013 to 2020.

Surgical site infections (SSIs) after thyroid surgery are rare complications, with incidence rates of 0.3%-1.6%. Using a Japanese database, we conducted exploratory analyses on the incidence of SSIs, investigated the incidence of SSIs by the National Nosocomial Infections Surveillance risk index, and identified the causative bacteria of SSIs. SSIs occurred in 50 (0.7%) of 7388 thyroid surgery cases. Risk index-0 patients had the lowest incidence rate of SSIs (0.41%). The incidence of SSIs in risk index-1 patients was 3.05 times the incidence of SSIs in risk index-0 patients. The rate of SSI occurrence for risk index-2 patients was 4.22 times the rate of SSI occurrence for risk index-0 patients. Thirty-one bacterial species were identified as the cause of SSIs in thyroid surgery cases, of which 12 (38.7%) SSIs were caused by Staphylococcus aureus and Staphylococcus epidermidis. Of the nine SSIs caused by Staphylococcus aureus, 55.6% (five cases) were attributed to methicillin-resistant Staphylococcus aureus. Therefore, routine prophylactic antibiotic administration should be avoided, while the target for administration should be narrowed, according to the SSI risk. Administration of prophylactic antibiotics, such as 2 g piperacillin or 1 g cefazolin, is considered appropriate.