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Solitary Pulmonary Mass due to Mycobacterium avium Infection in a Post-Traumatic Lung: A Case Report
Takayuki Nakano1,2,3, Shunsuke Yamada1,2, Kozo Morimoto4
1Respiratory Disease Center Tokyo General Hospital Tokyo Japan.
Abstract:
Solitary pulmonary nodule or mass like presentation of pulmonary Mycobacterium avium complex (MAC) disease is uncommon. We report a case of solitary pulmonary mass caused by MAC infection arising in a post-traumatic lung. A 56-year-old man with a history of left chest trauma, including pulmonary contusion and traumatic pneumatocele in the left lower lobe (LLL), was found to have a solitary mass in the same lobe. Chest computed tomography revealed a 33-mm subpleural mass in the LLL. Bronchoscopy was non-diagnostic. Serum anti-glycopeptidolipid-core IgA antibody was positive, but bronchoalveolar lavage culture and polymerase chain reaction (PCR) were negative. Thoracoscopic partial resection of the LLL was performed for diagnosis and treatment. Histopathology revealed epithelioid granulomatous inflammation with necrosis, and culture and PCR confirmed Mycobacterium avium infection. The postoperative course was uneventful, and the patient has been managed conservatively without additional antimicrobial therapy. To our knowledge, this is the first case of MAC infection arising in a post-traumatic lung as a solitary pulmonary mass.
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