Objective/Background: SSIs remain a significant cause of morbidity and mortality after surgery. One in eight patients develop SSI after exploratory laparotomies making it one of the major factors responsible for post-operative mortality and morbidity.

Atypical mycobacteria are responsible for a spectrum of diseases ranging from superficial skin infections to widely disseminated systemic infections.

Health care associated infections due to non-tuberculous mycobacteria is on the rise due to contaminated hospital water supplies, solutions, improperly sterilized instruments and devices. Our case is of an atypical mycobacterial infection in a patient with abdomino-thoracic trauma who underwent multiple surgeries.

Case presentation: A 24 year old gentleman presented with a penetrating stab injury to the abdomen and left hemi-thorax following an assault. Patient underwent an emergency exploratory laparotomy which revealed a 4 x 4 cm defect in the left hemi-diaphragm, through which the stomach was herniating into the left thoracic cavity. During the 2nd post-operative week, patient developed empyema thorax, for which pigtail drain was placed initially and later thoracotomy with decortication and intercostal drainage were performed. Following discharge after 2 weeks, he presented with fever, body pain and pus discharge from the previously inserted intercostal drain site. Pus obtained was positive for acid fast bacilli and gene expert was negative. Atypical mycobacterial infection was diagnosed based on high index of suspicion and he received treatment for 6 months.

Conclusion: This case highlights that identification of atypical mycobacterial infections in post-operative patients require a high index of suspicion. Management requires multi-drug approach and surgical intervention wherever necessary. Even with the existing sterilization techniques and preventive measure, atypical mycobacterial infection cannot be completely eliminated from a hospital set-up and hence must be considered in all nosocomial infections.