Comparación de dos métodos para la determinación de anticuerpos anti Trypanosoma cruzi incorporando un sistema documental

Introduction: Chagas disease or American trypanosomiasis is a systemic parasitic disease caused by Trypanosoma cruzi. Chagas disease has three clinical stages: the acute, indeterminate, and chronic stages. Objectives: i) to evaluate the performance of indirect hemagglutination (IHA) serological tests and indirect immunofluorescence (IFI) for the detection of antibodies against T. cruzi in Chagas patients; ii) to evaluate the frequency of positive results, and to calculate the concordance, sensitivity and specificity of the IHA method with respect to the IFI in a specific population; and iii) to implement a documentary system in terms of structure and format, as part of a Quality Management System (QMS). Materials and Methods: An observational, retrospective study was carried out, using inclusion and exclusion criteria. Results of patients who attended the Laboratory Service of the Sanatorio Privado Aconcagua, Cordoba, Argentina, were evaluated. The sensitivity and specificity of both methods were evaluated. Laboratory support documents were developed for these methodologies, as part of the QMS. Results: A total of 103 determinations were made: 12 agreed on their positivity for the IHA and IFI techniques, 88 results were negative for both techniques and 3 were discordant for both tests. The sensitivity and specificity for IHA were 92.3% and 97.8% respectively, and a concordance index of 97% was obtained. Conclusion: The two immunological techniques used as serological methods to study Chagas disease have good agreement in terms of their sensitivity and specificity. The implementation of a documentary system guarantees the support of a QMS.