Pleuritis Complicating Pulmonary Infection of Mycobacterium kyorinense.

Mycobacterium kyorinense is a rare mycobacterium. A 58-year-old man presented with sputum production and left-sided chest pain. Thickened left pulmonary cyst and pleural effusion were observed. A culture of the pleural fluid was negative, but the adenosine deaminase level was elevated. The patient was clinically diagnosed with M. kyorinense infection because this mycobacterium was identified in sputum samples on two occasions. The effusion and chest pain improved following treatment with levofloxacin, clarithromycin, and streptomycin. Identification of M. kyorinense is clinically significant because of its drug resistance. To our knowledge, this is the first reported case of pleuritis caused by a pulmonary M. kyorinense infection.