Complications of human schistosomiasis and their effect on levels of plasma copper, zinc and serum vitamin A.

Plasma copper, zinc, serum vitamin A and carotenoids were serially determined in three groups of patients: a group with active Schistosoma mansoni infection, a group with S. mansoni complicated by colonic polyposis and a group with S. mansoni associated with chronic salmonellosis. Results indicated a significant elevation in copper and significant depressions in zinc, vitamin A and carotenoids, the degree of which correlate with the associated complications of this disease. There was a positive correlation between zinc and vitamin A levels in all patients on admission suggesting a relationship between these two nutrients in schistosomal infection. Nutritional repletion of some patients of the first group resulted in significantly improved levels of copper, zinc, vitamin A and carotenoids before drug therapy was introduced indicating that alterations of these parameters are at least partially related to anaemia and poor nutritional status. At clinical recovery, levels of the four parameters were significantly improved in all patients from pre-treatment values but were within the normal range only in patients of the first group. This indicates that complications associated with schistosomiasis may delay normalization of copper, zinc and vitamin A levels beyond the clinical cure stage.