INTESTINAL PARASITIC INFECTIONS IN HUMAN-IMMUNODEFICIENCY-VIRUS (HIV)-POSITIVE AND HIV-NEGATIVE INDIVIDUALS IN SAN-PEDRO-SULA, HONDURAS

Honduras has at least five-times more human immunodeficiency virus (HI V)-infected individuals than any other country in Central America. The relationship between HIV status and the presence of intestinal parasi tes in this part of the world is unknown. This study presents the resu lts from a prospective, comparative study for the presence of parasite s in 52 HIV-positive and 48 HIV-negative persons in San Pedro Sula, Ho nduras. Infection with HIV was determined by microagglutination and co nfirmed by Western blot analysis. Parasites were detected in stools us ing formalin-ether concentration, and Kinyoun and trichrome staining. Age, sex, and clinical state of HIV infection were recorded for each s tudy participant. Our results indicate that Cryptosporidium parvum and Strongyloides stercoralis, which are intracellular or live in the muc osa, were found exclusively in persons infected with HIV. In compariso n, the prevalence of the extracellular parasites Giardia lamblia, Asca ris lumbricoides, and Trichuris trichiura was significantly higher (P < 0.05) in persons who were HIV-negative. Trichuris worms are in conta ct with the gut epithelium and less so with the mucosa, whereas Strong yloides lives within the gut mucosa. It is possible that changes in th e gut epithelium due to HIV infection do not affect the mucosa and the refore would not affect Strongyloides. We conclude that infection with HIV may selectively deter the establishment of certain intestinal par asites. This may be due to the fact that HIV-induced enteropathy does not favor the establishment of extracellular parasites. Intracellular and mucosal dwelling organisms, however, may benefit from pathologic c hanges and reduced local immune responses induced by the virus, which, in turn, may lead to higher prevalence among HIV-infected individuals .