[Interventional study in the natural evolution of Chagas disease. Evaluation of specific antiparasitic treatment. Retrospective-prospective study of antiparasitic therapy].

In this study is presented the comparative therapeutical experience comparing the Allopurinol, Benznidazol y Nifurtimox, in a prospective following in a long term, considering the responses to the parasitemia, specific serology and evolution of the clinic manifestations and complementaries in the 535 chronic chagasic cases (44.5%), instead of 668 patients who did not get any treatment (1203 chagasic cases followed for more than 5 years average). This study was done between April 1984 and April 1994 in patients with and without cardiopathy, in the Córdoba Hospital and the Salud Estudiantil Direccion, Universidad Nacional de Córdoba (U.N.C.); from them, 309 patients were given Allopurinol, 130 were given Benznidazol, and 96 were given Nifurtimox, with usual doses of Benznidazol and Nifurtimox, but with Allopurinol it was made an study evaluating the answering-doses, with a following time of post-therapeutic average of 55.6 months (D.S. = + -57 m.) The comparative parameters were the starting clinic characteristics, the qualitative and quantitative for Chagas, the pre-treatment xerodiagnostic, the treatment fulfillment, the treatment duration, the adverse effects, the treatment abandon, the time of postreatment longitudinal following till the last clinic-complementary evaluation, the clinic characteristics at the end of the following period; quantitative and qualitative serology for Chagas after the treatment, and post-treatment xerodiagnostic. It was observe a prevalence of Electrocardiographic Changes in the ECG in rest, in the first complementary evaluation in 76 of the 535 "Treated" and in the 225 "No-treated" patients, being Electrocardiographic abnormality proportion much more in the "No-treated" patients (P = 0.000000). After the end of the following period it was thought to have been found Miocardic Damage Progression in 120 patients "No-treated" and in 31 "Treated" patients (17.9% and 5.8% respectively) (P = 0.0000000). The complications in the evolution course were proved in 113 of the "No-treated" and in 19 of the "Treated" patients (16.9% and 3.5%, being this a statistically significant difference (P = 0.0000000). The mortality along the evolution was proved in 37 of the "No-Treated:" patients and in 7 of the "Treated" patients (5.5% and 1.3%), being this a statistically significant difference (P = 0.00019). The most tolerated drug and the one with the least incidence of therapeutic abandons was the Allopurinol. The xerodiagnostic negativization percentages were 72.5% for Allopurinol, 76.4% for Benznidazol and 76.5% for Nifurtimox (non-significant differences). A year and two years after the end of the treatment was made a titled serology with the Inmunofluorescence and Indirect Hemoaglutination Tests, getting significant statistical differences between the three drugs, resulting lower the values obtain after the treatment with Benznidazol and Nifurtimox than with Allopurinol (P = 0.0042 and P = 0.00039), respectively). The biggest proportion of Progression in the Cardiopathies, Complications, General Mortality and Attributed Mortality in "No Treated" (specially in older than 30 years) significant both for infected patient and slight cardiopathy, stabilises the possibility of stopping or reducing the morbid course of the Chronic Chagasic Cardiopathy, specially relevant in the formers, where the pathogenic process seems to be accelerated related to the latters. The negativation of the parasitemia and the parasitemia and the title disminution of the specific serology like effectiveness treatment parameters, and the stopping in the progression or dissemination of the incidence in new cases of Chronic Chagasic Cardiopathies were considered to be the real benefit of the antiparasitaric therapeutic in the Chagas Disease. As a conclusion, it is thought that the further the instauration of the specific antiparasitaric treatment the more the possibilities of effectiveness, as well as the increase in the probabilities of preventing or reducing the incidence of cardiopathy in chronic infected, or to stop its evolution and reduce its morbimortality in patients with already installed cardiopathy.