Prognosis of chronic pulmonary aspergillosis in patients with pulmonary non-tuberculous mycobacterial disease.

BACKGROUND

Pulmonary non-tuberculous mycobacterial disease (PNTM) is a known risk factor for chronic pulmonary aspergillosis (CPA). However, few studies have focused on the prognosis of PNTM-associated CPA. In the present investigation, we aimed to elucidate the clinical course and prognostic factors of CPA in patients with PNTM.

METHODS

We retrospectively investigated the medical records of 62 patients with CPA and a history of PNTM who were admitted to Kinki-chuo Chest Medical Center between 2010 and 2015. Co-morbidities, causative microorganisms, radiological findings, and outcomes were evaluated.

RESULTS

The patients' median age was 69.5 years, and the median follow-up period was 4.2 years. The major underlying diseases, other than PNTM and CPA, were old pulmonary tuberculosis, chronic obstructive pulmonary disease, and interstitial pneumonia. The most common causative NTM species were Mycobacterium avium complex (MAC; 37 patients; 59.7%) and Mycobacterium kansasii (20 patients; 32.3%). Survival was 83% after 1 year and 61% after 5 years. Use of systemic corticosteroids (hazard ratio: 3.32, 95% confidence interval: 1.23-9.51; P=0.00177) and C-reactive protein levels ≥ 5.0 mg/dL (hazard ratio: 8.96, 95% confidence interval: 2.15-62.9; P=0.0014) at the time of CPA diagnosis were associated with increased over-all mortality.

CONCLUSIONS

CPA frequently developed in patients with MAC and M. kansasii PNTM. The treatment course of PNTM was not associated with all-cause mortality. However, systemic corticosteroid use and high CRP levels were negative prognostic factors of CPA in patients with PNTM. Since the prognosis is poor, early diagnosis and treatment of CPA are important in patients with PNTM.