Risk Factors and Long-Term Prognosis for Coinfection of Nontuberculous Mycobacterial Pulmonary Disease and Chronic Pulmonary Aspergillosis: A Multicentre Observational Study in Japan.

backgroundNontuberculous mycobacterial pulmonary disease (NTM-PD) is a chronic respiratory infection with increasing prevalence and mortality worldwide. Coinfection with chronic pulmonary aspergillosis (CPA) is a significant complication of NTM-PD, often complicating treatment and resulting in poor prognosis.

objectiveIn this multicentre, retrospective cohort study, we examined the epidemiology, comorbidities, risk factors for CPA coinfection and long-term prognosis of patients with NTM-PD infected with CPA in Japan.

methodsPatients aged ≥ 18 years with newly diagnosed NTM-PD who visited 18 hospitals between 2010 and 2017 in Kyushu, Japan, were included. Medical records were reviewed for patient characteristics, mycobacterial species, laboratory data, radiological features, Aspergillus coinfection and all-cause mortality rates. Risk factors for CPA coinfection were analysed using multiple logistic regression, and survival analysis was performed before and after propensity score matching with risk factors.

resultsAmong 1304 patients with NTM-PD, 45 (3.5%) were diagnosed with CPA, including 42 with chronic progressive pulmonary aspergillosis. The risk factors for CPA coinfection included male sex, chronic obstructive pulmonary disease, oral corticosteroid use and cavity formation. All-cause mortality was significantly higher in patients with NTM-PD with CPA than in those without CPA (log-rank test, p < 0.001; crude hazard ratio [HR], 3.98). Survival analysis after propensity score matching suggested CPA was an independent poor prognostic factor (log-rank test, p = 0.036; adjusted HR, 1.59).

conclusionCPA is an independent poor prognostic factor in patients with NTM-PD. Clinicians must consider CPA when treating patients with NTM-PD, particularly those with high-risk factors, to ensure timely diagnosis and management.