Evaluation of cercarien hullen reaction [CHR] as a diagnostic test in chronic schistosomiasis and as a parameter for reinfection in acute cases

ABSTRACT

CHR was evaluated as a serodiagnostic test in relation to stool analysis, rectal snip and indirect hemagglutination test [IHA] in 25 cases with chronic active mansonian schistosomiasis. Sensitivities of CHR, IHA, rectal snip and stool analysis, respectively, proved to be 68%, 48%, 84%, and 52%. Rectal snip showed higher diagnostic efficacy 90% followed by CHR [77.5%], while IHA showed 67.5% diagnostic efficacy. To study CHR as parameter for pattern of reaction after treatment, 120 school children with acute mansonian schistosomiasis were examined. CHR was done before and one month after treatment. These children were followed up for one year by stool examination. Results of CHR test after treatment showed that the children who were not reinfected gave the highest degree of reaction, while those of high reinfection showed decrease in reaction. This denotes that anticercarial antibodies may play a role in resistance to reinfection and CHR test could be used as parameter for reinfection in such cases