[Infective etiology of diarrhea in adults with HIV infection in Dakar: a case-control study on 594 patients]

A survey was conducted in Dakar, Senegal from May 1997 to May 1999, to identify major types and prevalences of bacteria, parasites, fungi and Rotaviruses associated with diarrhea in relation to human immunodeficiency virus serostatus with the aim to provide guidance to physicians for case management. Etiologic agents were identified in a case-control study: cases were HIV-infected patients with diarrhea (HIV+ D+) and HIV seronegative patients with diarrhea (HIV- D+); controls were HIV-infected patients without diarrhea (HIV+ D-) and seronegative controls without diarrhea (HIV- D-). Strict enteric pathogens were identified by conventional methods. Different E. coli pathotypes were characterized by PCR. Opportunistic parasites such as Cryptosporidium and Microsporidium were identified by the Kinyoun method and trichromic stain of Weber respectively. Rotaviruses were identified with a commercial latex agglutination kit. Antimicrobial susceptibility testing was carried out by the disk diffusion method. A total of 594 patients were examined (158 HIV+D+, 121 HIV- D+, 160 HIV+ D- and 155 HIV- D-). In immunocompetent adults the main causes of diarrhea were: Shigella sp. (12.4%), Entamoeba histolytica (10.7%), Salmonella enterica (6,6%) and Giardia lamblia (4.9%). In the immunocompromised host the more frequent pathogens were: enteroaggregative E.coli (19,6%), Microsporidium(9.4%), Cryptosporidium sp.(8.2%), Rotavirus (8.2%), Shigella sp. (7.6%), Candida albicans (7.6%), Entamoeba histolytica (5,1%), Salmonella enterica (4.4%), Isospora belli (4.4%) and Blastocystis hominis (2,5%). Isolated enteropathogenic strains displayed high resistance to most antibiotics used in Senegal for treating diarrhea (tetracycline, cotrimoxazole); they were susceptible to quinolons and cephalosporins III .