SHORT COMMUNICATION Evaluation of Tests Based on the Antibody Response to Keyhole Limpet Haemocyanin and Soluble Egg Antigen to Differentiate

Specific IgG and IgM responses to soluble egg antigen (SEA) and keyhole limpet haemocyanin (KLH) were measured by ELISA in patients with acute and chronic schistosomiasis. The tests based upon IgM and IgG antibod-ies responses to KLH presented the best diagnostic discrimination, and can be used in conjunction with clinical and epidemiological data to the differential diagnosis of acute schistosomiasis. Key words: keyhole limpet haemocyanin- soluble egg antigens- enzime-linked immunosorbent assay The diagnosis of schistosomiasis mansoni is classi-cally made by stool parasitological techniques. In high and moderate prevalence areas, the detection of parasite eggs is simple and accurate (Tsang et al. 1983). However, the sensitivity of parasitological methods decreases in areas where the prevalence and intensitity of transmis-sion of schistosomiasis are low (Noya et al. 1997), and there are suggestions that, in this situation, serologic tests would be useful. The discrimination of acute and chronic stages of th