The influence of the parasitemia on the evolution of the chronic Chagas' disease

During 13 years, 190 individuals with chagasic infection were submitted to clinical and parasitological examinations to investigate the relationship between parasitemia and the evolution of chronic chagasic infection. Fifty-six patients with positive xenodiagnosis and 134 with negative exams were compared from 1988 to 91, it was found that 22 (39.3%) and 50 (37.3%), respectively, presented disease progression. The parasitemia was stratified into high, medium and low and the relation with the disease evolution showed that 5 (62.5%), 10 (41.7%) and 57 (36.1%), respectively, presented progressive disease, though without a statistically significant difference (p > 0.05). When 20 patients with persistent parasitemia in 1976/91, were compared with 59 with negative xenodiagnosis, a progressive evolution was observed in 6 (30%) and 17 (28.8%), respectively. Comparing six patients with high parasitemia and 59 with negative exams, it was verified that 3 (50%) and 17 (28.8%), respectively, showed progressive disease, but this was not statistically significant, (p > 0.05). Mean age with high, medium and low parasitemia were 39.6, 45.3 and 41.5 years, respectively, (p > 0.05). Mean age inpatients showing progressive, unaltered and regressive evolution was 46.4, 39.8 and 32.6years, respectively, with a statistically significant difference between progressive and regressive evolution (p < 0.05). It is suggested that high parasitemia did not have an influence on the evolution of the chronic infection.