HIV enteropathy: undescribed ultrastructural changes of duodenal mucosa and their regression after triple antiviral therapy. A case report

Diarrhea is the most common gastrointestinal symptom of AIDS, affecting 50–90% of patients with a very low CD4 lymphocyte count (1). Together with malabsorption and weight loss, it identifies the so-called wasting syndrome frequently reported during HIV infection (2). The origin of these symptoms is still uncertain since failure to identify an enteric pathogen occurs in as many as 30–40% of all cases. AIDS enteropathy has, thus, been defined as chronic, well-established diarrhea, lasting longer than 1 month, for which no infectious cause can be determined after a complete evaluation including electron microscopy of the small bowel, in patients with documented advanced HIV infection (3–6). The nosologic concept of an HIV enteropathy is supported by the detection of HIV proteins and nucleic acids in various cell types of the gut, such as epithelial cells, but also lymphocytes and macrophages. Although HIV itself does not seem to directly infect enterocytes, it may have an indirect effect via cytokines released from infected lymphoid cells, leading to villous atrophy and crypt atrophy, or, on the contrary, to hyperplasia, and possibly resulting in malabsorption, diarrhea, and weight loss (1, 3, 7).