Distinct Patterns of Autoantibodies Against G-Protein–Coupled Receptors in Chagasʹ Cardiomyopathy and Megacolon: Their Potential Impact for Early Risk Assessment in Asymptomatic Chagasʹ Patients

Objectives guishing the patterns of autoantibodies (AAB) against G-protein–coupled receptors in Chagasʹ cardiomyopathy and megacolon and the discovery of such a pattern in patients who are as yet asymptomatic could help to identify patients at high risk of developing the life-threatening complications of Chagasʹ disease. ound AB against receptors as beta 1 (beta1-AAB), beta 2 (beta2-AAB), and muscarinergic 2 (M2-AAB) are thought to be involved in the pathogenesis of Chagasʹ cardiomyopathy and megacolon, the predominant manifestations of Chagasʹ disease, which is the most serious parasitic disease in Latin America. s AAB, beta2-AAB, and M2-AAB were measured in the serum of asymptomatic Chagasʹ patients and in those with cardiomyopathy and/or megacolon. s all Chagasʹ patients with cardiomyopathy and/or megacolon had AAB. Predominance of beta1-AAB combined with M2-AAB in Chagasʹ cardiomyopathy and beta2-AAB with M2-AAB in megacolon was found. Such patterns were also found in 34% of the asymptomatic patients, of whom 85% possessed a beta1-AAB level typical for Chagasʹ cardiomyopathy. sions rcentage of asymptomatic Chagasʹ patients who had a specific AAB pattern and had a beta1-AAB level above a defined cutoff point mirrors very well the epidemiological situation, which showed that clinical manifestations develop in nearly 30% of Chagasʹ patients and cardiomyopathy in nearly 90% of them. We hypothesize that beta1-, beta2-, and M2-AAB measurement might be a useful tool for risk assessment in the indeterminate state of Chagasʹ disease to select patients for earlier involvement in care programs. However, prospective studies are needed to further evaluate this hypothesis.