Human Immunodeficiency Virus-Associated Gastrointestinal Disease: Common Endoscopic Biopsy Diagnoses

Abstract
The gastrointestinal (GI) tract is a major site of disease in HIV infection: almost half of HIV-infected patients present with GI symptoms, and almost all patients develop GI complications. GI symptoms such as anorexia, weight loss, dysphagia, odynophagia, abdominal pain, and diarrhea are frequent and usually nonspecific among these patients. Endoscopy is the diagnostic test of choice for most HIV-associated GI diseases, as endoscopic and histopathologic evaluation can render diagnoses in patients with non-specific symptoms. In the past three decades, studies have elucidated a variety of HIV-associated inflammatory, infectious, and neoplastic GI diseases, often with specific predilection for various sites. HIV-associated esophageal disease, for example, commonly includes candidiasis, cytomegalovirus (CMV) and herpes simplex virus (HSV) infection, Kaposi's sarcoma (KS), and idiopathic ulceration. Gastric disease, though less common than esophageal disease, frequently involves CMV, Mycobacterium avium-intracellulare (MAI), and neoplasia (KS, lymphoma). Small bowel biopsies and intestinal aspirates from HIV-infected patients often show HIV enteropathy, MAI, protozoa (Giardia, Isospora, Cryptosporidia, amebae, Microsporidia), and helminths (Strongyloides stercoralis). Colorectal biopsies demonstrate viral (CMV, HSV), bacterial (Clostridia, Salmonella, Shigella, Campylobacter), fungal (cryptococcosis, histoplasmosis), and neoplastic (KS, lymphoma) processes. Herein, we review HIV-associated GI pathology, with emphasis on common endoscopic biopsy diagnoses.