Study of contact activation in endemic hepatosplenomegaly.

Factors of the contact activation complex--FXII, FXI, high-molecular-weight kininogen (HMWK) and prekallikrein (PK) as well as D-dimer were measured in 68 schistosomal patients with and without co-existing chronic hepatitis B virus infection (HBV). Fifty-four cases had mixed hepatosplenic schistosomiasis and HBV infection whereas 14 were suffering from hepatosplenic (HS) schistosomiasis alone. A group of twelve age-matched, healthy individuals served as controls. All coagulation parameters were significantly reduced in both disease groups compared to the healthy controls. The decreased activity of the contact proteins could be attributed to decreased hepatic synthesis, consumption due to disseminated intravascular coagulation (DIC) and to the effect of endotoxins. In mixed schistosomiasis and HBV infections, however, the levels of the contact activation factors were not significantly different from those obtained in patients with HS alone. This apparently paradoxical finding does not, however, exclude a role for co-existing HBV infection in speeding up complications in hepatosplenic schistosomiasis.