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.

Cryptosporidium spp. during chemotherapy: a cross-sectional study of 94 patients with malignant solid tumor

“… 13 Indeed, at least two methods should be used in the diagnosis of cryptosporidiosis instead of a single method for more accurate results. 14 , 15 Timely and sensitive diagnosis of Cryptosporidium spp . in patients with malignant solid tumor receiving chemotherapy is of utmost importance since severe diarrhea may lead to exacerbation of cancer due to the interruption of the chemotherapy.…”

Diagnosis Of Cryptosporidiosis Using Affinity Purified Antigen

“…In recent years, many researchers have encountered Cryptosporidium and have tested different commercial diagnostics that depend on the coproantigen [42,43]; however, some of these immunological tests are not enough qualified to detect the anti-Cryptosporidium antibodies in sera of different cattle and buffalo breeds [44]. Therefore, an ELISA assay was adopted in the present study to compare the diagnostic potential of two prepared antigens: coproantigen and crude oocyst antigen.…”

“…This variation might be due to different antigen origins or the preparation method [45], or different quantities or qualities of the chemical reagents used [46]. Furthurmore, the antibody level against the antigen might differ with the immune response condition of the host, circulating immune complexes, and the mechanisms of immune evasion [44,45,47].…”

Development and Preliminary Application of a Triplex Real-Time Quantitative PCR Assay for the Simultaneous Detection of Entamoeba histolytica, Giardia lamblia, and Cryptosporidium parvum

“…According to some scholars ( Weitzel et al, 2006 ; Helmy et al, 2014 ; Uppal et al, 2014 ; Jerez Puebla et al, 2020 ), the results of immunological methods are not always accurate. It has also been pointed out that the reliability and reproducibility of results from only immunological assays are controversial ( Danišová et al, 2018 ). Few commercial kits for the diagnosis of intestinal protozoan copro-antigens have been reported in China ( Chen et al, 2012 ; Wang et al, 2021 ).…”