PREVALENCE OF ANTI-LEISHMANIA DONOVANI ANTIBODY AMONG BRAZILIAN BLOOD-DONORS AND MULTIPLY TRANSFUSED HEMODIALYSIS-PATIENTS

The prevalence of anti-leishmania donovani antibodies was investigated in 1,500 Brazilian blood donors and multiply transfused hemodialysis patients. Sera were tested using the fucose-mannose ligand (FML) ELISA , which was shown to have 100% sensitivity and 96% specificity for kal a-azar. Among 1,194 volunteer blood donors, seroreactivity was 9%, inc reasing to 25% in a periurban kala-azar focus. However, higher positiv ity (37%) was found in multiply transfused hemodialysis patients from Natal, where kala-azar is constantly present in low numbers (endemic), with sporadic outbreaks in localized regions (endemic and epidemic). Risk factors included blood transfusion, which was significantly assoc iated with the presence of anti-leishmania antibodies (chi(2) = 8.567, P < 0.005), but did not include potential exposure to sandfly bites ( chi(2) = 0.033, P > 0.1). The prevalence significantly decreased to 7% in hemodialysis patients from Rio de Janeiro, where kala-azar is only occasionally seen, and was 0% in patients undergoing continuous ambul atorial peritoneal dialysis. The prospective analysis of 27 FML-serore active donors from Natal revealed amastigotes of Leishmania in the bon e marrow of one subject while four had clinical complaints, including splenomegaly and hepatosplenomegaly. Our results point to the need for control of blood transfusion as a possible route for transmission of kala-azar in endemic areas.