Abstract
Mycobacterial lung disease is caused by nontuberculous mycobacteria (NTM), also known as atypical mycobacteria. NTM are widely distributed in the environment, particularly in soil and water; they may colonize the airways, gastrointestinal tract and genitourinary system, without the apparent signs of disease. Nevertheless, in some risk groups such as patients with chronic lung diseases or with immunodeficiency, mycobacterial lung disease is identified. Recently, increased recognition of mycobacterial lung disease in chronic obstructive pulmonary disease (COPD) patients has been observed, especially in those treated with high doses of inhaled corticosteroids. In the present paper, we describe the patient treated for many years due to COPD and bronchiectasis, with clinical and radiological picture suggestive of lung tumor, in whom final diagnosis of mycobacterial lung disease caused by Mycobacterium avium was made.