Sensitivity, specificity and comparison of three commercially available immunological tests in the diagnosis of Cryptosporidium species in animals

ABSTRACT The study was conducted to compare the specificity of immunological diagnostic methods used for the diagnosis of Cryptosporidium species capable of causing life-threatening infection in both immunosuppressed and immunocompetent patients. For the detection of Cryptosporidium species in 79 animals with diarrhoea, we used three Copro-antigen tests: RIDASCREEN® Cryptosporidium test, Cryptosporidium 2nd Generation (ELISA) and RIDA®QUICK Cryptosporidium. For immunoassays we used positive and negative samples detected by means of polymerase chain reaction and validated by sequencing and nested polymerase chain reaction to confirm the presence six different species of Cryptosporidium species. Prevalence of cryptosporidiosis in the entire group determined by enzyme immunoassay, enzyme linked immunosorbent assay, immuno-chromatographic test and polymerase chain reaction was 34.17%, 27.84%, 6.33% and 27.84%, respectively. Sensitivity of animal samples with enzyme immunoassay, enzyme linked immunosorbent assay, and immuno-chromatographic test was 63.6%, 40.9% and 22.7%, resp., when questionable samples were considered positive, whereas specificity of enzyme immunoassay, enzyme linked immunosorbent assay and immuno-chromatographic test was 75.9%, 78.9% and 100%, respectively. Positive predictive values and negative predictive values were different for all the tests. These differences results are controversial and therefore reliability and reproducibility of immunoassays as the only diagnostic method is questionable. The use of various Cryptosporidium species in diagnosis based on immunological testing and different results obtained by individual tests indicate potential differences in Copro-antigens produced by individual Cryptosporidium species.

Status quo and reflection of clinical immunology in laboratory medicine / 中华检验医学杂志

With the rapid advancement of immunology and molecular biology,many new revelations and ideas were drew for clinical immunology in laboratory medicine.In the current circumstances of application of clinical pathway management and individual medical care,how to accurately grasp these changes to build perfect quality system for clinical immunology laboratory,clarify the immunology laboratory pathway and integrate that into clinical pathway management,make solid progress for the promotion and application of individual diagnosis and evaluate the diagnostic value of new technique and item for clinical immunology laboratory accurately might be worth pondering for every people working in clinical immunology laboratory.In this paper,the status quo and reflection of clinical immunology is reviewed.