Three Autoantibodies Appear Common in Chagas' Disease
Study finds they may help to identify those at risk of developing symptomatic disease
FRIDAY, Jan. 29 (HealthDay News) -- Three autoantibodies (AAB) are often present in patients with Chagas' disease and may identify asymptomatic patients most likely to develop clinical manifestations and serious complications, according to a study in the Feb. 2 Journal of the American College of Cardiology.
Gerd Wallukat, Ph.D., of the Max-Delbrück-Centrum Berlin, and colleagues compared serum levels of AAB against the beta 1 adrenergic receptor (beta1), the beta 2 adrenergic receptor (beta2), and the muscarinergic 2 receptor (M2) in 29 healthy controls, 96 asymptomatic Chagas' patients, 57 patients with chronic Chagas' disease manifested as cardiomyopathy, 30 patients with chronic Chagas' disease manifested as megacolon, and 45 patients with chronic Chagas' disease manifested as cardiomyopathy combined with megacolon.
The researchers found that AAB to all three proteins were present in nearly all patients with cardiomyopathy. Nearly all patients with megacolon were positive for beta2 and M2 AAB, but only 38 percent were positive for beta1 AAB. Nearly all patients with both cardiomyopathy and megacolon had AAB against all three proteins. For asymptomatic patients, 34 percent were positive for beta1, 33 percent were positive for beta2, and 42 percent were positive for M2 AAB. Eighty-five percent of asymptomatic patients had beta1 levels typical of cardiomyopathy.
"The percentage of asymptomatic Chagas' 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 percent of Chagas' patients and cardiomyopathy in nearly 90 percent of them," the authors conclude.
The study was supported by Deutsche Gesellschaft für Klinische Chemie und Laboratoriumsmedizin for the Hans-Breuer-Stipendium.