Abstract

Kaposi sarcoma (KS) is a locally aggressive endothelial tumor, commonly diagnosed among individuals with acquired immunodeficiency syndrome (AIDS). The most typical site of involvement by KS is the skin, but in some cases, it can also affect other tissues and organs. Most patients with gastrointestinal involvement of Kaposi's sarcoma remain asymptomatic and they are often diagnosed on endoscopy or autopsy. However, there are cases of KS mimicking ulcerative colitis (UC), whereby clinical manifestations can confuse physicians. We report a 31 y old homosexual man who presented with rectal pain and bleeding. Patient was diagnosed eight years ago with HIV/ AIDS, and despite highly active retroviral therapy, he developed extensive skin lesions. Because of expressive rectal pain and bleeding, he underwent rectoscopy, which revealed ulcerous and hemorrhagic lesions. The rectoscopic and clinical presentation mimicked acute flare of UC, which was patient initial diagnosis. Tissue samples were collected for microscopical examination. After histological, histochemical and immunhistochemical examination of the sampled tissue, KS diagnosis was confirmed. The clinical manifestations of Kaposi sarcoma can be confused with acute exacerbation of ulcerative colitis often delaying the diagnosis. Therefore, early endoscopic evaluation with adequate biopsies could help in timely diagnosis and management of gastrointestinal KS (GI-KS) in patients with HIV/AIDS, even if they do not have skin lesions.

Keywords: Kaposi sarcoma; AIDS; HIV; Ulcerative colitis; Gastrointestinal KS