title: Clinical significance of small-intestinal microsporidiosis in HIV-1-infected individuals.
abstract: To assess the importance of microsporidiosis of the small intestine in the pathogenesis of chronic diarrhoea in HIV-1-infected individuals, duodenal biopsy samples from the following three patient groups were prospectively evaluated for bacterial, viral, and parasitic pathogens by standard methods, and for microsporidia by light microscopy: 55 consecutive HIV-1-antibody-positive subjects with unexplained diarrhoea of at least 3 weeks duration (group A); 38 HIV-1-seropositive subjects without diarrhoea (group B) who consecutively underwent upper gastrointestinal endoscopy for various reasons; and 7 patients without known risk factors for HIV infection with chronic unexplained diarrhoea (group C). In groups A and B most subjects had had previous AIDS-defining opportunistic infections and the median peripheral blood CD4 lymphocyte count was less than 0.1 x 10(9)/l. Microsporidia were detected as the single pathogen in 15 of the group A compared with 1 (in whom diarrhoea subsequently developed) of the group B patients (p = 0.001) and none of the group C patients. With the exception of 4 of the group A patients, no other intestinal pathogens were identified in any of the patients. The median peripheral blood CD4 count was significantly lower in patients with detectable microsporidia than in those without microsporidiosis (0.03 x 10(9)/l vs 0.06 x 10(9)/l; p = 0.03); in all patients with microsporidiosis, the CD4 count was equal to or less than 0.1 x 10(9)/l. 13 patients with microsporidiosis were treated with metronidazole, in 10 of whom treatment led to a substantial improvement or disappearance of diarrhoea within days of starting therapy, but did not result in eradication of the parasite in the 5 patients who underwent repeat biopsy. The findings suggest that small-intestinal microsporidiosis is an important cause of chronic unexplained diarrhoea in HIV-1-infected individuals with pronounced cellular immune deficiency. This infection should therefore be added to the list of AIDS-defining opportunistic infections.
authors.affiliation: Department of Internal Medicine, N.H. Swellengrebel Laboratory of Tropical Hygiene, Royal Tropical Institute, Amsterdam, The Netherlands.
authors.forename: J K
authors.initials: JK
authors.lastname: Eeftinck Schattenkerk
authors.forename: T
authors.initials: T
authors.lastname: van Gool
authors.forename: R J
authors.initials: RJ
authors.lastname: van Ketel
authors.forename: J F
authors.initials: JF
authors.lastname: Bartelsman
authors.forename: C L
authors.initials: CL
authors.lastname: Kuiken
authors.forename: W J
authors.initials: WJ
authors.lastname: Terpstra
authors.forename: P
authors.initials: P
authors.lastname: Reiss
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000150:complications* / Q000276:immunology; D000328:Adult; D000818:Animals; D000981:Antiprotozoal Agents / Q000627:therapeutic use; D015496:CD4-Positive T-Lymphocytes; D003967:Diarrhea / Q000276:immunology / Q000469:parasitology*; D004378:Duodenal Diseases / Q000276:immunology / Q000469:parasitology; D056890:Eukaryota / Q000302:isolation & purification; D005260:Female; D015497:HIV-1; D006801:Humans; D007111:Immunity, Cellular; D007411:Intestinal Diseases, Parasitic / Q000150:complications* / Q000276:immunology / Q000469:parasitology; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D009894:Opportunistic Infections / Q000150:complications* / Q000276:immunology; D011528:Protozoan Infections / Q000150:complications* / Q000276:immunology / Q000469:parasitology
chemical_list: D000981:Antiprotozoal Agents