Mycobacterium kansasii, a nontuberculous mycobacterium, can cause pulmonary disease presenting clinical and radiological similarities to tuberculosis. M. kansasii infection has been associated with risk factors such as bronchiectasis, chronic obstructive pulmonary disease, tuberculosis sequelae, pneumoconiosis and immunosuppression. Herein, we describe a case of pleural effusion in a 67-year-old patient with chronic obstructive pulmonary disease and a history of pulmonary tuberculosis. The histological analysis demonstrated a granulomatous chronic process and acid-fast bacilli positivity, suggesting a diagnosis of pleural tuberculosis. M. kansasii was detected both in pleural fluid cultures and in cultures of tissue samples. We discuss the differential etiologic diagnosis with other infectious agents of granulomatous diseases, and we address treatment options.

Keywords: Mycobacterium kansasii; Mycobacterium infections; Pleural effusion; Case reports