Development of a case of Mycobacterium avium complex disease from right pleural effusion

: Moist pleurisy in patients with Mycobacterium avium Complex (MAC) is rarer than tuberculosis. We encountered an extremely rare case of MAC disease in a 75-year-old man who initially had only right pleural effusion. Gaffky VII was detected in the pleural effusion, and Mycobacterium avium was identified by culture and PCR. Although administration of antitubercular agents (RFP, INH, EB, and SM) + CAM and thoracic lavage were repeated, the Gaffky persisted strongly. Accordingly, pulmonary decortication and filling of the cavity with an omental flap were performed as surgical treatments. However, fistulas were formed between the remaining empyema cavity and the surgical wounds. Fenestration was also carried out. Postoperatively, centriacinar abnormalities appeared on computed tomography (CT). It has been reported that MAC disease begins with centriacinar abnormalities and the incidence of the lymphatic developmental pattern was low. Tuberculosis (the idiopathic pleuritis type) is considered to be caused this pattern from the primary infection focus. Therefore, the onset of unilateral effusion is extremely rare in patient with MAC disease, suggesting that the lymphatic developmental pattern occurs less frequently in patients with MAC disease. Furthermore, in this case, we speculated that centriacinar abnormalities were the MAC infection foci and could be detected by CT due to surgical invasion.