文摘
Clinical background is an essential data to achieve diagnosis of chronic diarrhea from infectious or immune dysfunction etiology. In HIV patients when the immune deficiency is important, diarrhea can be related to opportunistic infection. This diarrhea may be due to parasitic or bacterial infection. In primary immunodeficiency disorders, villous atrophy may also explain chronic diarrhea. Giardiasis, responsible for diarrhea and malabsorption, should always be looked for, because immune competent patients are not spared. Some specific clinical data (surgery history, achlorhydria, diabetes, immune deficiency, etc.) may be relevant to diagnose gut microbial pullulation. Whipple disease, although rare, should be kept in mind as treatment is easy and prognosis without treatment is very poor.