Atypical mycobacteria infections of surgical sites: a case series

Atypical mycobacteria (ATB) are a rare cause of surgical site infections (SSIs). They present with clinical features of erythema, induration, and sinus formation, which recur despite conventional treatment. Early diagnosis is difficult and requires a high index of suspicion for further investigations to confirm atypical mycobacterial infection. Treatment encompasses a combination of polymicrobial agents and surgical debridement.

To describe the clinical presentation, diagnostic challenges, and treatment outcomes of atypical mycobacterial infections in surgical sites.

Written informed consent was obtained from all participants in this observational retrospective descriptive study. Scientific and ethical clearance was granted by the Ethical Clearance Committee at M.S Ramaiah Medical College and Hospital, Bengaluru. The study included 5 female patients from a tertiary care hospital in Bengaluru, India, who presented with SSIs that did not resolve with standard treatment. Discharge or wound scrapings from these patients with delayed infections were examined for the causative agent, with ATB isolates identified using solid and liquid culture methods.

ATB were isolated in 3 clean and 2 clean-contaminated surgeries, that is, in 60% and 40% of cases, respectively. Discharge alone did not yield growth in any of the cases (0%), whereas tissue scrapings revealed ATB in all 5 patients (100%). The most common organism cultured was Mycobacterium fortuitum (60%), followed by Mycobacterium abscessus (20%) and Mycobacterium chelonae (20%). Clarithromycin and ciprofloxacin alone for a period of 3 to 6 months yielded a 100% cure rate (5 of 5 patients).

ATB infections are a rare cause of postoperative SSIs. These infections require multimodal management, with complete resolution possible after appropriate therapy. This series emphasizes the significance of ATB infection of surgical sites as a notable cause of postoperative morbidity.