Outcomes of patients undergoing treatment for non-tuberculous mycobacteria lung disease

Accurate definition of treatment outcome is a crucial step in the management of patients undergoing treatment for non-tuberculous mycobacteria lung disease (NTM-LD). The NTM-NET recently issued a consensus definition for key outcomes useful for clinical trial design. The aim of the present study was to explore outcomes on NTM-PD patients according to those definitions in a real-life setting. An observational, retrospective study enrolling consecutive adults with NTM-LD undergoing treatment at the Villa Marelli Institute, Milan, Italy, from 2007 to 2017 was conducted. Diagnosis of NTM-LD and standard operating procedures were based on ATS/IDSA 2007 guidelines. Out of 182 patients (68% females; median age: 69 years) enrolled, 132 (70%) were infected by M. avium complex, 20 (11%) by M. kansasii, and 16 (8.4%) by M. xenopi. 30 (20%) patients had fibro-cavitary disease and 144 (73.8%) had nodular-bronchiectatic disease. The antibiotic therapy was compliant with the ATS/IDSA 2017 guidelines in 85% of the patients. During a median follow-up period of 31 months, 118 (64.8%) patients were cured. Treatment halted occurred in 26 (14.3%), recurrence in 19 (10.4%), reinfection in 9 (4.9%), treatment failure in 8 (4.4%) patients, and relapse in 2 (1.1%) patients. Three patients died. Systemic arterial hypertension [OR: 2.3; P=0.03], number of positive sputum culture before treatment [OR: 1.5; P=0.03], and radiological tree-in-bud pattern [OR: 0.3; P=0.008) were independent risk factors for unsuccessful outcome. More than one third of NTM-LD patients undergoing treatment experienced an unsuccessful outcome and our findings highlight the urgent need of multidisciplinary interventions to improve them