Khoor A, Leslie K O, Tazelaar H D, Helmers R A, Colby T V
Department of Pathology, Mayo Clinic, Jacksonville, FL, USA.
Am J Clin Pathol. 2001 May;115(5):755-62. doi: 10.1309/JRDC-0MJV-ACA3-2U9L.
The clinicopathologic spectrum of infections due to nontuberculous mycobacteria (NTM) includes cavitary disease, opportunistic infection, and nodular disease associated with bronchiectasis. We report a less well-described manifestation of NTM infection: 10 immunocompetent patients without preexisting bronchiectasis had radiographic evidence of diffuse infiltrative lung disease. The most common symptoms were dyspnea, cough, hypoxia, and fever. All 10 patients had used a hot tub. Histologic examination revealed exuberant nonnecrotizing, frequently bronchiolocentric, granulomatous inflammation in all cases. In 1 case, necrotizing granulomas were also noted. The inflammation often was associated with patchy chronic interstitial pneumonia and organization. Cultures revealed NTM in all cases (Mycobacterium avium complex in all but 1 case), but staining for acid-fast bacilli was positive in only 1 case. Four patients received corticosteroids alone for presumed hypersensitivity pneumonia, 4 were treated with antimycobacterial therapy, and 2 received both. All patients demonstrated significant improvement at the time of follow-up. These findings suggest that disease due to NTM may manifest as diffuse infiltrates in immunocompetent adults and that hot tub use may be an important risk factor for this disease pattern.
非结核分枝杆菌（NTM）感染的临床病理谱包括空洞性疾病、机会性感染以及与支气管扩张相关的结节性疾病。我们报告了一种较少被描述的NTM感染表现：10例免疫功能正常且无既往支气管扩张的患者有弥漫性浸润性肺病的影像学证据。最常见的症状是呼吸困难、咳嗽、低氧血症和发热。所有10例患者都使用过热水浴缸。组织学检查显示，所有病例均有旺盛的非坏死性、常为细支气管中心性的肉芽肿性炎症。1例还发现有坏死性肉芽肿。炎症常伴有斑片状慢性间质性肺炎和机化。所有病例培养均发现NTM（除1例为鸟分枝杆菌复合群外其余均为该菌群），但抗酸杆菌染色仅1例呈阳性。4例患者因疑似过敏性肺炎单独接受了皮质类固醇治疗，4例接受了抗分枝杆菌治疗，2例两者均接受了治疗。所有患者在随访时均有显著改善。这些发现表明，NTM所致疾病在免疫功能正常的成年人中可能表现为弥漫性浸润，使用热水浴缸可能是这种疾病模式的一个重要危险因素。
