Radiological factors associated with the recurrence of Mycobacterium avium complex pulmonary disease: a multicentre retrospective cohort study

Mycobacterium avium complex pulmonary disease (MAC-PD) frequently recurs after treatment but predictors of recurrence remain unclear. We retrospectively analysed patients with successfully treated MAC-PD from two tertiary centres. Chest CT findings—including bronchiectasis, cellular bronchiolitis, cavity, nodule and consolidation scores—were assessed before and after treatment. Multivariable competing risk regression analyses were performed to identify factors associated with recurrence. Among 538 patients, 216 (40.1%) experienced recurrence. A higher post-treatment cellular bronchiolitis score was independently associated with recurrence (adjusted subdistribution HR 1.64, 95% CI 1.46 to 1.84; p<0.001). A score ≥3 was associated with increased recurrence risk in both nodular bronchiectatic and fibrocavitary phenotypes. Residual cellular bronchiolitis on post-treatment CT demonstrated the strongest predictive performance and may serve as a radiological marker of recurrence risk.