Box IV.

Definitions of mild-moderate and severe non-tuberculous mycobacteria (NTM) disease

Mild-moderate (non-severe disease)

Mild-moderate symptoms

No signs of systemic illness

Absence of lung cavitation and extensive lung disease

AFB smear-negative in the pulmonary specimens

Severe disease

Presence of severe symptoms and signs of systemic illness

Presence of lung cavitation and extensive lung involvement

Pulmonary specimens positive for AFB smear

AFB, acid-fast bacilli; NTM-PD, non-tuberculous mycobacterial pulmonary disease. Source: Ref. 1