Clinical impact of chronic pulmonary aspergillosis in patients with pulmonary nontuberculous mycobacterial disease and colonization: a multicentre prospective cohort study

Pulmonary nontuberculous mycobacterial (NTM) infection and chronic pulmonary aspergillosis (CPA) are interconnected diseases, but their relationship remains poorly understood.
In this prospective, multi-centre study conducted in Taiwan between August 2020 and January 2024, 365 patients with cultures positive for Mycobacterium avium complex, Mycobacterium kansasii, or Mycobacterium abscessus complex were followed until August 2024. Serum Aspergillus-specific IgG levels were measured at baseline and follow-up.
Among these patients, 123 (33.7%) tested positive for Aspergillus-specific IgG (>40 mgA/L), and 33 (9.0%) were diagnosed with CPA (10 at initial diagnosis, 23 developed CPA during a median follow-up of 18 months). Patients with NTM pulmonary disease (NTM-PD) demonstrated significantly higher cumulative incidence of CPA compared to those with NTM pulmonary colonization (NTM-PC) (2.7%, 8.3%, and 14.7% vs. 0%, 2.9%, and 5.3% at 1, 2, and 3 years, respectively; p = 0.0408). CPA development was linked to worse overall survival (adjusted hazard ratio [aHR] 3.96, 95% confidence interval [CI]: 1.47–10.69, p = 0.0066) as well as higher risk of radiographic progression (adjusted odds ratio [aOR] 7.43, 95% CI: 2.17–32.11, p = 0.0030). Longitudinal assessment of Aspergillus-specific IgG in 119 patients showed nine with positive seroconversion, and two were subsequently diagnosed with CPA.
These findings indicate that approximately one-third of pulmonary NTM isolation patients have elevated Aspergillus-specific IgG, about 10% develop CPA, and CPA development is associated with poor survival. Therefore, longitudinal monitoring of Aspergillus-specific IgG is warranted to facilitate early detection and management of CPA in patients with pulmonary NTM isolation.

Elevated Aspergillus IgG was observed in one-third of NTM patients, and 10% developed CPA.
The development of CPA is associated with worse outcomes in this population.
Serial monitoring of Aspergillus IgG levels may aid in early diagnosis and intervention.

Elevated Aspergillus IgG was observed in one-third of NTM patients, and 10% developed CPA.
The development of CPA is associated with worse outcomes in this population.
Serial monitoring of Aspergillus IgG levels may aid in early diagnosis and intervention.