Early, intermediate, and late acute stages in Chagas' disease: a study combining anti-galactose IgG, specific serodiagnosis, and polymerase chain reaction analysis.

Abstract

Abstract. The acute phase of Chagas' disease was classified as early, intermediate, and late based on the levels of anti-Gal␣ 1,3 Gal IgG (Gal) and specific IgM (M) and IgG (G) anti-T. cruzi reactivity. While the early phase was MϩG-GalϪ, the intermediate phase was MϩG-Galϩ, MϩGϩGalϪ, or MϩGϩGalϩ, and the late phase was MGϩGalϩ. This sequence of stages was consistent with our previous studies on acute-phase proteins. Analysis by the polymerase chain reaction (PCR) of parasite DNA in 65 blood samples of children living in Cochabamba, Bolivia showed a significant correlation (90.8%) between ELISA and PCR positivity. A lower correlation was observed between indirect hemagglutination, PCR (58%), and ELISA. Electrocardiographic analysis of 43 children studied by the PCR did not show any alteration typical of acute chagasic myocarditis. The PCR positivity was observed in eight samples where only Gal was increased, suggesting a very early T. cruzi infection, when specific antibodies were not yet present. By associating anti-Gal IgG with specific serology, early T. cruzi infection can be detected with greater precision. We suggest the use of anti-Gal antibody reactivity as an aid for the detection of recent T. cruzi infections, at least in endemic areas where diseases caused by other trypanosomatids do not overlap.Chagas' disease, which is caused by infection with Trypanosoma cruzi, is an important public health problem that affects approximately 16-18 million individuals, mainly in Latin America.

Integrate Study of a Bolivian Population Infected by Trypanosoma cruzi, the Agent of Chagas Disease

“…The two others cases may be considered as false positive PCR, but a singular situation has been previously described in Bolivia where cases of positive xenodiagnosis with negative serology were reported (Brenière et al 1984). High sensitivity of PCR using kDNA primers has been demonstrated in different studies performed with Bolivian populations in endemic areas , Antas et al 1999. Seroprevalence increased regularly with the age of the patients as previously observed in a study of 140 individuals in a rural community of Cochabamba department (Pless et al 1992).…”

Active transmission of human chagas disease in Colima Mexico

“…In this sense, it is remarkable the presence of one asymptomatic 2 years old girl. This finding, added to the presence of very suggestive cases of acute Chagas in another 2 girls, and in an adult with fever and hepatomegaly, although not confirmed by parasitemia, but positive for IIF and PCR, that are considered strong evidence of acute Chagas disease by some authors (Añez et al 1999, Antas et al 1999, verifies the assumption that there is active transmission of AT and human Chagas disease in Colima. For this reason, acute Chagas disease should be considered in the differential diagnosis of persistent fever, especially in cases accompanied by systemic manifestations in areas where domiciliated triatominae are detected.…”

Current concepts in immunoregulation and pathology of human Chagas disease

“…Although classic studies have suggested a suppressive response in the early phases of human T. cruzi infection [24,25], it is clear that the immune response mounted is efficient for controlling patent parasitemia. It has been suggested that B-cell activation leading to lytic antibody production is important in parasite elimination during the acute phase [26][27][28]. Although studies of endomyocardial biopsies from acute patients have shown the presence of CD4+ and CD8+ T cells in the inflammatory myocarditis [29], the function of these cells during the acute phase has not been determined.…”