Concurrent infections and neutrophil phagocytic function in Nigerians with urinary schistosomiasis.

Bacteria infections, parasitic infections and neutrophil phagocytic function were assessed in 60 urinary schistosomiasis (USS) subjects and 36 healthy controls. Only Salmonella was isolated from the blood samples of few USS subjects (3%) and controls (1%). The species of bacteria detected in the urine of USS and control subjects are Escherichia coli, Salmonella, Staphylococcus aureus, Streptococcus faecalis and Klebsiella. There was no significant difference in the proportion of the USS subjects with bacteriuria compared with the controls (X2 = 0.20, P > 0.20). Higher proportions of USS subjects compared with the controls were concurrently infected with Ascaris lumbricoides, hookworms, Giardia lambila and Taenia solium. In contrast, significantly higher proportion of the control subjects were concurrently infected with Plasmodium falciparum and Schistosoma mansoni. There was no significant reduction in neutrophil phagocytic function of USS subjects compared with the controls (P > 0.49). This study suggests that S. haematobium protects its host from certain blood dwelling parasites and that Nigeria USS subjects expressed adequate neutrophil phagocytic function. These may explain the absence of clinical manifestations of bacterial and viral infections in these subjects.