Evaluation of the "Symbiosys" immunoassay for the serological diagnosis of Chagas disease.

For the laboratory diagnosis of Chagas disease several tests are commonly used. Sensitivity and specificity must always be taken into account, as well as the fact that these methods vary when we are dealing with an acute or chronic stage of the parasitosis. Also, it is important to remember that the initial stage of Trypanosoma cruzi infection is characterized by the presence of the parasite in the blood and not by clinical or epidemiologic findings, for example. As for the diagnosis in the chronic stage, serological tests are usually the first choice.