Diagnosis of early prepatent schistosomiasis by cystatin capture enzyme-linked immunosorbent assay

ABSTRACT

To test the efficacy of detecting anti-Schistosoma mansoni cysteine proteinase antibodies [CP Abs] by cystatin capture [CC] ELISA in the diagnosis of prepatent schistosomiasis [before egg passing], 253 schistosome negative individuals were selected and divided into two groups. The first comprised 118 children whose first water contact occurred in March and April 1999 [primarily infected] and the second included 135 individuals previously treated for schistosomiasis [re- infected]. All the individuals were followed up tri weekly by stool for detecting schistosome eggs and by serological tests for detecting antibodies against CP and anti-soluble egg antigens [SEA] by ELISA technique. CP seropositivity was detected in 92 from all the examined individuals, 38 out of them were primarily infected [PI] children and the rest [54] were re-infected patients. Anti-SEA IgM Abs were sought in 92 CP seropositive sera and seropositivity rate was lower in 38 PI children than 54 re-infected individuals. The anti-SEA seropositivity rate in PI children was 5% in pre-patent and 94.4% in post-patent. None of the 161 CP seronegative individuals passed eggs up to 12 weeks