Dysentery in patients infected with human immunodeficiency virus in Zimbabwe: an emerging role for Schistosoma mansoni and Escherichia coli O157?

Information on bloody diarrhoea in HIV-positives is scarce. A prospective s tudy was therefore performed, in Zimbabwe, to determine and compare the pat hogens associated with bloody diarrhoea in 25 antiretroviral-naive HIV-infe cted patients and 15 non-HIV-infected patients. Stool cultures and colonic biopsies were performed. Shigella was isolated from 18 (45%) of the subject s, Schistosoma mansoni from eight (16%), Escherichia coli H7:O157 from thre e (8%) and Campylobacter jejunii from two (5%). There was no evidence of Sa lmonella, Entamoeba histolytica or cytomegalovirus infection. Shigella dyse nteriae type-1 occurred more often in the HIV-negatives than the HIV-positi ves (P = 0.02). Although HIV-associated bloody diarrhoea in Zimbabwe appear s to be most frequently caused by Shigella, it may also be commonly the res ult of infection with Sc. mansoni or shiga-toxin-producing E. coli. A large r study specifically to examine the role of Sc. mansoni and E. coli O157 is warranted.