PCR and sero-diagnosis of chronic Chagas' disease. Biotechnological advances.

In the acute phase of Chagas' disease, when the parasitemia is high, diagnosis can be easily made using conventional parasitological methods. During the chronic phase, due to the low parasitemia, diagnosis is performed mainly by immunological methods. Conventional serological techniques are limited by cross-reactivity with other parasitic diseases, non-standardization of reagents, and the diversity of technical procedures. Methods are being developed to improve the sensitivity and specificity of diagnosis using molecular approaches. PCR-based detection systems and the use of recombinant antigens in ELISA are the most promising.