title: Localization of infection by the microsporidian Enterocytozoon bieneusi in the gastrointestinal tract of AIDS patients with diarrhea.
abstract: OBJECTIVE
  We compared the level of Enterocytozoon bieneusi infection at different sites within the small intestine among patients with AIDS.
  
  
  METHODS
  The level of E. bieneusi infection of each patient biopsy was determined and compared using semi-thin plastic section light microscopy and transmission electron microscopy (TEM).
  
  
  METHODS
  Nine subjects with chronic diarrhea who had endoscopic biopsies of either proximal (bulb) or distal (fourth portion) duodenum plus proximal jejunum (just past ligament of Treitz), either simultaneously or within a few months of each other were studied. All patients had TEM-confirmed diagnoses of E. bieneusi intestinal microsporidiosis.
  
  
  RESULTS
  The intensity of infection was always greater in biopsies taken from the patients' jejunum compared with those taken from the duodenal bulb. In one patient, the duodenal bulb biopsy was negative while the jejunal biopsy, taken at the same time, was positive. The distal duodenum was usually, but not always, equal to the jejunum in terms of parasite burden. Esophageal, gastric, and colorectal biopsies from these and other patients were negative for E. bieneusi.
  
  
  CONCLUSIONS
  For the diagnosis of E. bieneusi to evaluate chronic diarrhea in AIDS patients, upper intestinal endoscopy biopsies should be taken at the most distal site possible.
authors.affiliation: Department of Pathology, George Washington University Medical Center, Washington, DC 20037.
authors.forename: J M
authors.initials: JM
authors.lastname: Orenstein
authors.forename: M
authors.initials: M
authors.lastname: Tenner
authors.forename: D P
authors.initials: DP
authors.lastname: Kotler
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000150:complications*; D000818:Animals; D001706:Biopsy; D002908:Chronic Disease; D003967:Diarrhea / Q000469:parasitology; D006801:Humans; D007410:Intestinal Diseases / Q000150:complications / Q000469:parasitology* / Q000473:pathology; D007421:Intestine, Small / Q000469:parasitology; D016815:Microsporea / Q000302:isolation & purification*; D016881:Microsporidiosis / Q000150:complications / Q000469:parasitology* / Q000473:pathology; D009894:Opportunistic Infections / Q000150:complications / Q000469:parasitology*