埃希氏阿米巴是一种厌氧原生动物，感染人体会导致阿米巴病。大多数感染是无症状的，然而，临床表现包括肠道和肠外宿主。在少数情况下，患者可能出现阿米巴瘤：由炎症内核和周围纤维化组成的颗粒组织肿块，通常在盲肠/升结肠发现，与慢性阿米巴感染有关。一名50岁的患者出现肠梗阻的体征和症状。他的炎症标志物升高，正在接受治疗并保持病毒抑制的HIV阳性。在腹腔探查手术中发现肝曲部狭窄伴有脱肌反应，以及横结肠中部系膜边缘的壁增厚和硬化，还有弥漫性结节病变。组织学证实了埃希氏阿米巴感染。该寄生虫存在两种形式：囊泡阶段和滋养体阶段，其中滋养体阶段引起侵袭性疾病。肠阿米巴感染的表现范围从无症状携带者状态、结肠炎到脓肿形成和肠穿孔。管理原则是消灭侵袭性滋养体，根除寄生虫的肠道携带，并处理并发症，如肠梗阻、暴发性结肠炎或毒性巨结肠，采取手术治疗。这个案例确定了一个没有旅行史的肠梗阻患者的罕见原因。即使除了HIV之外缺乏显著的风险因素，临床医生也应该意识到结肠肿块/狭窄的感染性原因除了恶性原因外的其他原因。埃希氏阿米巴是发展中国家贫困社区的感染，应该在结肠肿块的肿瘤样颗粒组织的鉴别诊断中始终保持高度警惕。版权所有 © 2023 作者。由Elsevier Ltd.出版。保留所有权利。

Entamoeba histolytica is an anaerobic protozoan. It infects humans causing Amoebiasis. Most infections are asymptomatic; however, clinical manifestations include intestinal or extraintestinal. In rare instances, patients can present with Ameboma: a mass of granulation tissue consisting of a core of inflammation with peripheral fibrosis related to chronic amoebic infection usually found in the cecum/ascending colon.A 50-year-old patient presented with signs and symptoms of bowel obstruction. He had raised inflammatory markers and was HIV positive on treatment and virally suppressed. At laparotomy a hepatic flexure stricture with desmoid reaction, and wall thickening with induration at the mesenteric border of mid-transverse colon was found, with disseminated nodular disease. Histology confirmed entamoeba histolytica infection.The parasite exists in two forms: a cyst stage and a trophozoite stage: the form causing invasive disease. The presentation of intestinal amoebiasis ranges from an asymptomatic carrier state, colitis, to abscess formation and bowel perforation The management principles: to eliminate the invading trophozoites and eradicate the organism's intestinal carriage and manage complications such as obstruction, fulminant colitis, or toxic megacolon with surgery.This case identifies a rare cause of bowel obstruction in a patient without a travel history. Even with the lack of significant risk factors other than HIV, clinicians should be aware of the infective causes of colonic mass/stricture outside of malignant causes. Entamoeba histolytica is an infection of impoverished communities in developing countries, it should remain high on our differential for tumour-like granulation tissue in the colon.Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.