Usefulness of Bacterial Culture of Drainage Fluid for Predicting Surgical Site Infection After Crohn’s Disease Surgery

Abstract Aim Early detection of surgical site infection (SSI) allows for appropriate management after Crohn's disease (CD) surgery. The aim of this study was to evaluate the usefulness of bacterial culture of postoperative drainage fluid after CD surgery. Methods This study included 110 patients with CD who underwent surgery with bowel resection between January 2010 and March 2020 at Osaka University Hospital. Patients with only perianal surgery or incomplete records were excluded. Risk factors for SSI were evaluated in the context of clinical findings, including bacterial culture of postoperative drainage fluid, and bacterial species related to SSI were also examined. Results Of 110 patients, 18 (16.4%) developed SSI. Organ/space SSI developed in six, and a positive bacterial culture of drainage fluid (D‐Posi) was found in five (83.3%). Of 104 patients without organ/space SSI, 31 (29.8%) were D‐Posi (P = .027). Similarly, 68.8% with incisional SSI were D‐Posi, whereas 26.6% without incisional SSI were D‐Posi (P = .0021). Multivariate analysis revealed that D‐Posi was an independent risk factor in both organ/space and incisional SSI. Bacterial examination showed that Pseudomonas aeruginosa and Enterococcus faecalis were significantly detected in patients with SSI. Conclusion This study suggests the usefulness of postoperative drainage fluid bacterial culture for early diagnosis of SSI after CD surgery.