Pathology Section, Rashid Hospital, Dubai, United Arab Emirates.
Gastroenterology Unit, Rashid Hospital, Dubai, United Arab Emirates.
Ann Diagn Pathol. 2020 Dec;49:151638. doi: 10.1016/j.anndiagpath.2020.151638. Epub 2020 Oct 8.
Mycobacterium avium-intracellulare complex (MAIC) is a nontuberculous opportunistic infection in immunocompromised patients. Involvement of the gastrointestinal tract (GIT) is usually part of a disseminated disease in AIDS patients with a low CD4 count, however with standard antiretroviral therapy (ART), a localized presentation is more likely. It can affect any part of the GIT, mostly the duodenum and typically as patches. Incomplete or refractory ART for HIV-strains, therapy-related side effects, noncompliant or incomplete treatment to previous MAIC infections, superimposed complications and comorbid opportunistic infections may result in atypical clinical, endoscopic and histopathologic manifestations. We performed a retrospective review study retrieving cases of MAIC in duodenal endoscopic biopsy. We found five cases of MAIC in HIV/AIDS patients. They were males with an average age of 40-years. They showed different histopathologic features, variable patterns of MAIC-histiocytic infiltrates, and varying intensity of intracellular acid-fast positive bacilli. Enterocytes vacuolization and transepithelial elimination were also observed. Three cases were associated with cytomegalovirus and cryptococcal infections. A case was complicated by lymphangiectasia-associated protein-losing enteropathy. Initially, three cases were morphologically missed. Ziehl-Neelsen stain helped reach the correct diagnosis. Pathologists have an important role in patients' management by guiding clinicians to the correct diagnosis. Pathologists should be aware of these different histopathologic manifestations, their potential pitfalls, look for certain helpful clues complemented with multiple levels and special stains. In particular, AFB stains are mandatory in all mucosal biopsy specimens from HIV/AIDS patients regardless of their appearances.
鸟分枝杆菌复合群（MAC）是免疫功能低下患者的非结核分枝杆菌机会性感染。胃肠道（GI）受累通常是 AIDS 患者低 CD4 计数时全身性疾病的一部分，但随着标准抗逆转录病毒治疗（ART）的应用，局部表现更常见。它可以影响 GI 的任何部位，主要是十二指肠，通常呈斑块状。HIV 株的 ART 不完全或难治、治疗相关的副作用、对以前 MAC 感染的不依从或不完全治疗、叠加的并发症和合并机会性感染可能导致不典型的临床、内镜和组织病理学表现。我们进行了一项回顾性研究，检索了十二指肠内镜活检中 MAC 的病例。我们发现 5 例 HIV/AIDS 患者患有 MAC。他们均为男性，平均年龄为 40 岁。他们表现出不同的组织病理学特征、MAC 组织细胞浸润的不同模式以及细胞内抗酸杆菌的不同强度。还观察到肠上皮细胞空泡化和跨上皮细胞消除。3 例与巨细胞病毒和隐球菌感染有关。1 例并发淋巴管扩张相关蛋白丢失性肠病。最初，3 例在形态学上被遗漏。Ziehl-Neelsen 染色有助于做出正确诊断。病理学家通过指导临床医生做出正确诊断，在患者管理中发挥着重要作用。病理学家应该了解这些不同的组织病理学表现、其潜在陷阱、寻找某些有帮助的线索，并辅以多个层面和特殊染色。特别是，无论 HIV/AIDS 患者的黏膜活检标本外观如何，都必须进行 AFB 染色。
