Total and specific anti-Trypanosoma cruzi immunoglobulin E in pericardial fluid samples from patients with chronic Chagas disease.

Levels of total and specific anti-Trypanosoma cruzi immunoglobulin E (IgE) were determined by immunoenzymatic assay among 101 samples of pericardial fluid from patients who had died in one trypanosomiasis endemic area in central Brazil. These samples were divided into 6 groups. Group I, 17 samples from patients with the cardiac form of Chagas disease; group II, 11 samples from patients with the digestive form of Chagas disease, presenting megaoesophagus and/or megacolon; group III, 41 samples from patients with the indeterminate form of Chagas disease; group IV, 4 samples from patients with both cardiac and digestive forms of Chagas disease; group V, 5 samples from patients who suddenly died and were seropositive for T. cruzi antibodies; group VI, 23 samples, used as a control group, which came from patients seronegative for T. cruzi antibodies. Significantly high levels of total IgE were observed in groups I, II, III, IV and V when compared with group VI (mean concentrations 708-1157 iu/mL compared with 394 iu/mL). In groups I-V, 32 samples (41%) had specific anti-T. cruzi IgE antibodies. The individual percentage positivity rates in these groups were 64.7% (group I), 45.4% (group II), 34.1% (group III), nil (group IV), and 40.0% (group V). A significant correlation between total IgE and specific anti-T. cruzi IgE was observed only in the samples from patients with the cardiac form of Chagas disease (group I).