Mycobacterium abscessus Complex Infections Among Lung Transplant Recipients: A Multicenter Retrospective Cohort Study...

Area of Science:

• Infectious Diseases
• Transplant Immunology
• Pulmonary Medicine

Background:

• Mycobacterium abscessus complex poses a significant threat to lung transplant recipients (LTRs), often leading to life-threatening conditions.
• The presence of M. abscessus is frequently considered a contraindication for lung transplantation (LT).

Purpose of the Study:

• To investigate the incidence and outcomes of Mycobacterium abscessus infection in lung transplant recipients in Canada.
• To determine the impact of pre-transplant M. abscessus colonization or infection on post-transplant outcomes.

Main Methods:

• A multicenter retrospective cohort study was conducted across 4 Canadian LT centers.
• Included were LTRs transplanted between 2006-2016 with positive respiratory samples for M. abscessus pre- or post-transplantation.
• Pulmonary disease was defined by American Thoracic Society criteria, with a minimum 5-year follow-up.

Main Results:

• The incidence of M. abscessus disease post-LT was 1.1/1000 transplant-years, and colonization was 0.5/1000 transplant-years.
• Among 15 patients with pre-transplant M. abscessus, 53% developed post-transplant infection.
• Pre-transplant eradication was associated with significantly lower post-transplant disease (0% vs. 85.7%, p=0.001).
• Overall survival was comparable between LTRs with and without pre-transplant M. abscessus (p=0.37).
• However, mortality was higher in patients with pre-transplant infection who did not achieve eradication (57.1%) or developed post-transplant disease (66.7%).

Conclusions:

• Mycobacterium abscessus is an infrequent cause of infection in lung transplant recipients.
• While overall survival is similar for LTRs with pre-transplant M. abscessus, eradication before transplantation is critical.
• Failure to eradicate M. abscessus pre-transplant is linked to increased post-transplant disease and mortality.