目的：探讨艾滋病（acquired immune deficiency syndrome，AIDS）合并巨细胞病毒（cytomegalovirus，CMV）感染患者的临床病理特征，及其与其他常见病毒感染及非感染性疾病间的鉴别诊断。方法：2013年至2023年期间，收集上海市公共卫生临床中心病理科经CMV免疫组化染色确诊阳性、人类免疫缺陷病毒（human immunodeficiency virus，HIV）阳性、临床资料完整、符合纳入标准的38例患者，结合组织学形态、特殊染色、原位杂交检查结果及临床资料进行综合分析。结果：患者以发热、恶心呕吐、胃部不适、腹疼腹泻为主，少数病例呕血、便血、咳嗽、咳血。胃肠镜活检获取组织32例，其中送检2个部位以上的10例；淋巴结2例，皮肤、颌下腺、肺、肛周活检各1例。病理形态学显示，胃肠道黏膜糜烂伴急慢性炎为主，3例溃疡形成；淋巴结活检均为淋巴滤泡反应性增生；皮肤、肛周、颌下腺肺穿刺标本均见急慢性炎细胞浸润，局灶凝固性坏死。本研究中有35例患者的上皮细胞、内皮细胞、巨噬细胞、成纤维细胞等体积增大，核内见嗜酸性病毒包涵体，周围有空晕，似“鹰眼”样；另3例患者活检标本（消化道黏膜组织）中未见明确的包涵体结构。免疫组化检测提示，38例CMV均阳性、单纯疱疹病毒（herpes simplex virus，HSV）阴性、潜伏膜蛋白（latent membrane protein，LMP）阴性。特殊染色示，抗酸染色分枝杆菌阳性3例，过碘酸希夫RNA（periodic acid Schiff，PAS）染色和六胺银染色横结肠内查见马尔尼菲篮状菌、胃部白色念珠菌及肺部曲霉菌各1例。EB病毒编码的RNA（Epstein-Barr encoded RNA，EBER）原位杂交检测结果38例均阴性。结论：AIDS合并CMV感染的独特病理学特征是受感染细胞的体积增大，核内出现嗜酸性病毒包涵体，呈“鹰眼”样，结合免疫组化可精准定位CMV在细胞内的表达，同时结合特殊染色和原位杂交技术能为EB病毒、HSV、呼吸道病毒和霍奇金淋巴瘤等病变的鉴别诊断提供有力的证据。

Objective This study aims to explore the clinicopathologic features of patients with acquired immune deficiency syndrome (AIDS) with cytomegalovirus (CMV) infection, and to analyze the differential diagnosis with other common viral infections and non-infectious diseases. Methods A total of 38 patients confirmed CMV-positive by immunohistochemical staining, HIV-positive, with complete clinical data and meeting the inclusion criteria were collected from the Department of Pathology, Shanghai Public Health Clinical Center from 2013 to 2023. A comprehensive analysis was conducted based on histological morphology, special staining, in situ hybridization, and clinical data. Result The main symptoms of the patients were fever, nausea and vomiting, gastric discomfort, abdominal pain and diarrhea, while a few cases presented with hematemesis, hematochezia, cough, and hemoptysis. Tissue samples from 32 cases were obtained via gastrointestinal endoscopic biopsies, including 10 cases with biopsies from more than 2 sites. 2 cases were from lymph nodes, and 1 case each from skin, submandibular gland, lung, and perianal biopsies. Pathological results showed gastrointestinal mucosal erosion with acute and chronic inflammation, with ulceration forming in 3 cases. Lymph node biopsies showed reactive lymphoid follicle hyperplasia. Acute and chronic inflammatory cell infiltration with focal coagulative necrosis was observed in skin, perianal tissue, submandibular gland, and lung specimens. In this study, 35 patients showed enlargement of epithelial cells, endothelial cells, macrophages, and fibroblasts, with eosinophilic viral inclusions in the nuclei surrounded by a clear halo, resembling an "owl's eye". In the other 3 patients, no definite inclusion bodies were observed in their biopsy specimens (gastrointestinal mucosal tissue). Immunohistochemical testing showed that all 38 cases were positive for CMV and negative for herpes simplex virus (HSV) and latent membrane protein (LMP). Special staining revealed that acid-fast staining was positive for Mycobacterium in 3 cases, while periodic acid Schiff stain and methenamine silver staining detected one case each of Talaromyces marneffei in the transverse colon, Candida albicans in the stomach, and Aspergillus in the lungs. The results of in situ hybridization for Epstein-Barr encoded RNA (RNAEBER) were negative in all 38 cases. Conclusion The distinctive pathological feature of AIDS patients with CMV infection is the enlargement of infected cells, with eosinophilic viral inclusions in the nuclei resembling an "owl's eye". Combined with immunohistochemistry, precise locali-zation of CMV expression within the cells can be achieved. Additionally, special staining and in situ hybridization provide robust evidence for the differential diagnosis of lesions caused by EBV, HSV, respiratory viruses, and Hodgkin's lymphoma.