Investigation of a Mycobacterium fortuitum prosthetic joint infection outbreak at two ambulatory surgery centers in Tennessee.

OBJECTIVE

This study outlines the investigation into an outbreak of Mycobacterium fortuitum infections involving 17 cases undergoing hip or knee surgeries at two ambulatory surgery centers (ASCs) in Tennessee from January 2023 to November 2024. Notably, the outbreak could not be attributed to contaminated water sources, which are typically associated with non-tuberculous mycobacteria (NTM) outbreaks, presenting a unique challenge.

METHODS

Outbreak investigation steps included Infection Prevention (IP) assessments, case-control study, environmental sampling, whole genome sequencing, and a healthcare personnel (HCP) exposure questionnaire.

RESULTS

IP assessment highlighted several concerns, including no formal facility water management program (WMP), a lack of dedicated IP personnel and certified sterile processing staff, the absence of a formalized system for tracking surgical site infections, and a notable gap in understanding the requirements for reporting diseases. The case-control findings revealed a significant association between the presence of a surgical technologist in the operating room during the procedures and the occurrence of NTM infections, indicated by an odds ratio of 55.77 (95% CI [3.16-985.44]; P = 0.0097). Thirteen clinical isolates collected at one ASC and three additional isolates collected at a second ASC were highly related by whole genome sequencing.

CONCLUSION

The study further elucidates valuable insights gained from the outbreak response, including the gaps in surveillance within the ambulatory surgical setting and systematic collection of cultures from environmental sources. It emphasizes the importance of thorough vetting, onboarding, continuing education, and practice monitoring for HCP.