The relationship between uncomplicated schistosomiasis and hepatitis B infection

Clinical and laboratory findings and hepatitis B virus (HBV) markers were compared in 105 patients with uncomplicated schistosomiasis mansoni, schistosomiasis haematobium, or both infections. 34 (32%) had HBs antigen (Ag); 51 (49%) had anti-HBs and/or anti-HBc; 20 (19%) had no markers for HBV. In comparison with the non-HBV-infected group, the group with HBsAg had more complaints of nausea and vomiting, and higher mean values for serum bilirubin and aspartate aminotransferase, and were less likely to complain of loose stools. In comparison with the non-HBV-infected group both groups having HBV markers were older, more likely to have received prior therapy (parenteral therapy in particular) for schistosomiasis, less likely to complain of blood in their stools, and more likely to have higher serum total proteins, albumin, globulin, and alanine aminotransferase. This study supports two mechanisms which could cause an association between HBV infection and schistosomiasis: (i) self-selection by patients with schistosomiasis seeking medical care for symptoms due to HBV infection and (ii) iatrogenic infection with HBV during parenteral treatment for schistosomiasis. It also suggests that much of the clinical morbidity ascribed to uncomplicated chronic schistosomiasis may be caused by a concomitant occult HBV infection.