Molecular identification of coproantigens of Cryptosporidium parvum compared to conventional staining techniques.

To compare the immunologic techniques to the conventional staining methods (mainly modified Ziehl Neelsen = MZN), 93 children (65 immunocompromised and 28 immunocompetent) potentially at risk of Cryptosporidium parvum were studied. Using MZN, a prevalence of 10.7% in diarrhoeic children was found. ELISA coproantigen and detection of 23 KDa band of immunoblotting by serum IgG were sensitive and specific. They gave 85.7% sensitivity, 100% specificity, 100% diagnostic accuracy, 100% positive predictive value and 98.9% negative predicttive value. ELISA detection of serum IgG gave 85.7% sensitivity, 97.7% specificity, 96.8% diagnostic accuracy, 75% positive predictive value and 98.9% negative predictive value. So, 23KDa band determined by ELISA is a valuable sensitive and specific mean of diagnosing cryptosporidiosis as this antigen is a consistent target of humoral immune response.