This study evaluated Trypanosoma cruzi parasitemia in persons with chronic Chagas disease, compared the parasitemia in human immunodeficiency virus (HIV)-positive and -negative subjects, and, for HIV-positive subjects, analyzed the association between parasitemia and occurrence of acquired immunodeficiency syndrome-defining illnesses, CD4 cell counts, HIV loads, and antiretroviral therapy. In total, 110 adults with chronic Chagas disease (29 HIV positive, 81 HIV negative) were studied. T. cruzi parasitemia was evaluated by xenodiagnosis, blood culture, and direct microscopic examination of blood. T. cruzi parasitemia was detected significantly more frequently in HIV-positive than in HIV-negative subjects (odds ratio, 12.3; 95% confidence interval, 3.7-41.2). HIV-positive patients also had higher levels of parasitemia. No statistically significant association was seen between parasitemia and the variables of interest among the HIV-positive subjects.

Abstract. We report a human immunodeficiency virus

To evaluate the possible role of parasitemia on Chagas' disease reactivation in Chagas' disease/human immunodeficiency virus (HIV) coinfection cases and the impact of HIV coinfection on Trypanosoma cruzi genetic diversity, 71 patients with Chagas' disease (34 HIVϩ and 37 HIV-) were surveyed. Moreover, 92 T. cruzi stocks from 47 chronic chagasic patients (29 HIVϩ and 18 HIV-) were isolated and analyzed by multilocus enzyme electrophoresis and a random amplified polymorphic DNA procedure. High parasitemia appeared to play a major role in cases of Chagas' disease reactivation. In HIVϩ patients, the genetic diversity and population structure (clonality) of T. cruzi was similar to that previously observed in HIV-patients, which indicates that immunodepression does not modify drastically genotype repartition of the parasite. There was no apparent association between given T. cruzi genotypes and specific clinical forms of Chagas' disease/HIV associations. Chagas' disease, the American trypanosomiasis, is widespread from the southern United States (where the indigenous cases are rare) to northern Argentina. It is characterized by two successive phases, an acute one, with high parasitemia, and a chronic one, with low parasitemia. Although efficient measures of transmission control have been implemented in some countries (by eliminating the insect vector), Chagas' disease still is a priority health problem in Latin America. Chagas' disease/human immunodeficiency virus (HIV) associations appear to be a growing threat in large Latin American cities, and can be extremely pathogenic, with severe cases involving the central nervous system (CNS) with either tumoral lesions or meningoencephalitis. 1-5