The validity of indirect haemagglutination assay (IHA) in the detection of Schistosoma haematobium infection relative to microscopic examination

Abstract

Background : Several schistosome serodiagnostic assays have been developed over the last years, most of them are designed for the detection of anti-schistosomal antibodies which might remain for long periods of time after treatment, this study aimed to evaluate commercially available kit, indirect hemagglutination assay (IHA) as alternative to microscopic examination to diagnose S.haematobium infection Subjects and methods: This study is a cross-sectional study designed to evaluate an indirect hemagglutination assay (IHA), a commercially available kit was used for determine urinary schistosomiasis in the study population, this performed on 50 positive S.haematobium samples and 50 negative samples for individuals matching in age and gender, in addition, urine microscopic examination was done for detection of S.haematobium eggs by sedimentation centrifugation and nuclepore filtration techniques. Results: The results showed that an indirect hemagglutination assay (IHA) had a sensitivity of 42% and specificity of 80%. PPVs were 67.7% whereas NPVs were 57.97 %. As for diagnostic efficiency, it was 61%, where the area under the curve (AUC) was bad 0.58. Conclusion and Recommendations: Years ago this commercial kit which used in this study and also used in all medical laboratories in Egypt for detection of schistosome antibody in serum is called Fumouze bilharzial IHA Kit, this study showed low sensitivity (42%) and specificity (80%), that lower than expected results for detection of antibody and the kit is generally more expensive than microscopic examination for S.haematobium infection.