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Centro de Investigaciones Regionales Dr. Hideyo Noguchi, Universidad Autónoma de Yucatán

2012, Number 3

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Rev Biomed 2012; 23 (3)

Estimation of the sensitivity and specifi city of three Toxoplasma gondii diagnostic tests in women with spontaneous abortions for two localities of Yucatán, Mexico using a Bayesian model

Vado-Solís IA, Suárez-Solís V, Jiménez-Delgadillo B, Segura-Correa JC

Language: Spanish
References: 20
Page: 95-103
PDF size: 402.74 Kb.


ABSTRACT

Introduction. The presence of cysts of T. gondii in edible meat, represent a potential risk for humans, if the meat is consumed raw or undercooked. Accurate and reliable diagnostic tests are essential for detecting, surveillance and control of intermediate hosts to minimize the risks of human infections.
Objective. To evaluate the sensitivity and the specifi city of three diagnostic tests to detect the presence of Toxoplama gondii in women with spontaneous abortion in two localities of Yucatan, Mexico, using Bayesian procedures
. Materials and Methods. The tests were evaluated using Bayesian analysis which allow the estimation of the Sensitivity (Se) and Specifi city (Sp) in absence of a gold standard. Two scenarios were compared: 1) Using a priori uniform distributions, and 2) Using a priori beta distributions of the parameters.
Results. The Se and the Sp using a priori uniform distributions for the ELISA test to detect IgG were 0.915 and 0.568; and for IgM ELISA yielded 0.670 and 0.948 levels. PCR test results were 0.747 and 0.981 respectively. The results using a priori beta distribution of the parameters were 0.952 and 0.806 for IgG, 0.856 and 0.986 for IgM, and 0.712 and 0.995 for PCR, respectively.
Conclusion. The results showed that no single test results were suffi cient to diagnose T. gondii infections in women with spontaneous abortions. Further, the inclusion of beta parameters in the a priori beta distribution of the model also improved the estimates of Se and Sp of the tests.


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