Immunoglobulin concentration in treated human acute Chagas disease. A follow-up study.

Immunoglobulin M, G, and A concentrations were studied by radial immunodiffusion technique in 16 individuals (two were 16 and 14 yr of age, respectively, while the remaining 14 uere 15 yr of age or less) with acute Trypanosoma cruzi infection. Serum samples were obtained from these patients beginning with the onset of symptoms and continuing until several months after treatment with nifurtimox was completed. Soon after infection the concentration of IgM was higher than the average found in healthy children. Some of the samples also had higher values than those found in children with other acute infections. At this time isolated increases in IgG and/or IgA concentrations were also found in T. cruzi-infected patients. Immunoglobulin concentrations had usually returned to normal when treatment with nifurtimox was completed, both in the patients with negative serology and in those who remained positive. However, some of the sera showed isolated higher IgM, IgG, and/or IgA values than those found in healthy controls.