Distinct patterns of autoantibodies against G-protein-coupled receptors in Chagas' cardiomyopathy and megacolon. Their potential impact for early risk assessment in asymptomatic Chagas' patients.
OBJECTIVE
Distinguishing the patterns of autoantibodies (AAB) against G-protein-coupled receptors in Chagas' 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 Chagas' disease.


BACKGROUND
Such AAB 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 Chagas' cardiomyopathy and megacolon, the predominant manifestations of Chagas' disease, which is the most serious parasitic disease in Latin America.


METHODS
Beta1-AAB, beta2-AAB, and M2-AAB were measured in the serum of asymptomatic Chagas' patients and in those with cardiomyopathy and/or megacolon.


RESULTS
Nearly all Chagas' patients with cardiomyopathy and/or megacolon had AAB. Predominance of beta1-AAB combined with M2-AAB in Chagas' 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 Chagas' cardiomyopathy.


CONCLUSIONS
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% of Chagas' 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 Chagas' disease to select patients for earlier involvement in care programs. However, prospective studies are needed to further evaluate this hypothesis.
Wallukat
Gerd
G
Max-Delbrück-Centrum Berlin, Berlin, Germany.
Muñoz Saravia
Silvia Gilka
SG
Haberland
Annekathrin
A
Bartel
Sabine
S
Araujo
Raul
R
Valda
Gregorio
G
Duchen
Diana
D
Diaz Ramirez
Ivan
I
Borges
Adrian Constantin
AC
Schimke
Ingolf
I
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D001323:Autoantibodies / Q000097:blood*; D002478:Cells, Cultured; D002598:Chagas Cardiomyopathy / Q000276:immunology*; D005260:Female; D006339:Heart Rate / Q000276:immunology; D006801:Humans; D008297:Male; D008531:Megacolon / Q000276:immunology*; D008875:Middle Aged; D032383:Myocytes, Cardiac / Q000276:immunology; D051381:Rats; D043562:Receptors, G-Protein-Coupled / Q000276:immunology*; D012189:Retrospective Studies; D018570:Risk Assessment; D055815:Young Adult
D001323:Autoantibodies; D043562:Receptors, G-Protein-Coupled