This is the first report of a congenitally transmitted case of Chagas
disease occurring in Mexico, in a febrile premature newborn girl with
low birth weight, hepatosplenomegaly and pneumonitis. Tryganosoma cruz
i blood infection was detected using both direct smears and concentrat
ed blood preparations. The patient's mother had a positive serological
reaction by two techniques for anti-T. Cruzi antibodies. Two years af
ter anti-chagastic treatment, the child has had a normal evolution, he
r serology is negative, and no abnormalities have been detected by ele
ctrocardiography.