ABSTRACT
Nontuberculous mycobacterial infection is rarely accompanied by pleural involvement. We report a very rare case of Mycobacterium intracellulare pulmonary disease accompanied with pleural effusion. A 76-year-old man was admitted to our hospital because of dyspnea. A chest radiograph and CT showed bilateral bronchiectasis and bronchopneumonia accompanied with right pleural effusion. The fluid was lymphocyte-dominant exudative effusion, and microbiological examinations of the effusion, including staining and culturing, proved negative. However, one month after admission, subsequent cultures of bronchial washing fluid revealed the presence of M. intracellulare. The patient's effusion was gradually resolved with antibiotic treatment, including clarithromycin.