Opportunistic protozoan diarrhoea.

In the developed world, a significant increase in the incidence of protozoan diarrhoea was observed following the AIDS epidemic. The profound immunodeficiency associated with advanced HIV disease produced increased susceptibility to opportunistic protozoan infections. The resultant profuse diarrhoea, malabsorption and weight loss contributed to the high morbidity and mortality rates associated with the epidemic.

Elevated mucosal addressin cell adhesion molecule-1 expression in acquired immunodeficiency syndrome is maintained during antiretroviral therapy by intestinal pathogens and coincides with increased duodenal CD4 T cell densities.

Reduced intestinal CD4 T cell numbers and gastrointestinal disease are common features of acquired immunodeficiency syndrome (AIDS). Duodenal lymphocyte densities and mucosal addressin cell adhesion molecule (MAdCAM)-1 expression were analyzed in patients with AIDS after highly active antiretroviral therapy (HAART). Compared with human immunodeficiency virus (HIV)-seronegative individuals, HAART-naive patients with AIDS displayed reduced duodenal CD4 T cell densities.