Western blot test and elisa test free#
True differences of test accuracy among studies are not directly observable because studies are not free of random and systematic errors such as technical variation of test characteristics (among laboratories by time), laboratory proficiency, choice of gold standard or cut-off value for interpretation, and handling of intermediate or uninterpretable results. In addition, the serological diagnostic techniques used may have considerable influence on the estimate obtained for the true seroprevalence however, comparative studies on serological techniques used in cats are limited and scarce. Variation in sensitivity and specificity is mainly attributable to differences among the reference population studied and sampling strategies that are used for the validation procedure. However, ELISA and WB tests were reported to be more sensitive than IFAT. It is important to highlight that sensitivity and specificity estimates of these serological methods in cats unfortunately were rarely evaluated. Numerous epidemiological studies demonstrated the presence of anti- Leishmania antibodies in feline sera by means of different techniques such as IFAT, ELISA or WB as previously reviewed elsewhere. One potential field of application of WB method is the discrimination between subclinical infections and disease. infantum antigens stimulating antibody production, but is less frequently used in veterinary practice for the diagnosis of leishmaniosis. Western blot (WB) analysis, mainly a qualitative serological method, distinguishes the molecular weight of the L. Conversely, reading of ELISA plates is rapidly operated in a plate reader at the required absorbance and, in addition to the selected cut-off, Sp and Se strongly depend on the kind of antigen used. Moreover, appropriate setting of cut-off level is crucial in determining sensitivity (Se) and specificity (Sp) of this test. However, this technique depends on the operator’s skills and experience for the microscopical reading of IFAT antigen slides. IFAT method is considered the reference technique by the World Organization for Animal Health (OIE). For both IFAT and ELISA, quantification using antibody titer or optical density allows classification of antibody levels against L.
IFAT and ELISA are amongst the most common serological techniques used for the diagnosis and for clinical and research studies on canine and feline L. infantum are increasingly being reported in Europe. Moreover, clinical cases of feline leishmaniosis and subclinical infections due to L. infantum is strongly suspected as infected cats are able to transmit the parasite to vector sand flies. Dogs are the primary reservoir host however other animal species can be infected, including cats.
Leishmaniosis due to Leishmania infantum is a zoonotic vector-borne disease of worldwide importance, transmitted by phlebotominae sand flies. The overall performance of all serological techniques was good and the most accurate test for anti- Leishmania antibody detection in feline serum samples was WB. IFAT was more sensitive than ELISA (75 vs 70%) for the detection of subclinical infection while ELISA was better for diagnosing clinical leishmaniosis when compared with IFAT (98 vs 97%).
The median seroprevalence in the sample used for evaluating the performance of tests was estimated at 0.27. The latent data and observations from the joint posterior were simulated in the Bayesian approach by an iterative Markov Chain Monte Carlo technique using the Gibbs sampler for estimating sensitivity and specificity of the three tests.
Western blot test and elisa test software#
Statistical analysis was performed through a written routine with MATLAB software in the Bayesian framework. WB was considered positive in presence of at least a 18 KDa band. MethodsĬut-offs were set at 80 titre for IFAT and 40 ELISA units for ELISA. infantum antibodies in feline serum samples obtained from endemic ( n = 76) and non-endemic ( n = 64) areas and from cats affected by feline leishmaniosis ( n = 21) by a Bayesian approach without a gold standard. The aim of the present study was to assess diagnostic performance of IFAT, ELISA and WB to detect anti- L. The immunofluorescent antibody test (IFAT), the enzyme-linked immunosorbent assay (ELISA) and western blot (WB) are the serological tests more frequently used. Anti- Leishmania antibodies are increasingly investigated in cats for epidemiological studies or for the diagnosis of clinical feline leishmaniosis.
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