Antibody drop in newborns congenitally infected by Trypanosoma cruzi treated with benznidazole.
OBJECTIVE
To compare the drop of Chagas antibody titres between non-infected and congenitally infected newborns treated by two doses of benznidazole, aiming at evaluating the recovery time and giving recommendations regarding serological criteria of recovery.


METHODS
During a clinical trial, the drop of Trypanosoma cruzi antibody titres measured by ELISA tests was followed during the first year of life in congenitally infected newborns treated with different doses of benznidazole and compared to T. cruzi antibody titres in non-parasitaemic newborns. Confirmation of recovery was given by two negative serological tests: Chagas Stat-Pak (CSP) (immunochromatography) and Chagatest v3.0 (ELISA).


RESULTS
In non-parasitaemic infants of infected mothers, antibodies of maternal origin disappeared in <8 months while in infected infants, T. cruzi antibodies decreased more slowly and disappeared in 9-16 months allowing to confirm the recovery. All CSP tests were negative before the ninth month while about 10% of ELISA tests remained positive at the 12th month.


CONCLUSIONS
Recovery may be confirmed in most cases at 10 months. The CSP test was compared to Chagatest v3.0 ELISA and appeared to give a reliable response. The decrease rate of antibodies does not depend on treatment modes.
Chippaux
Jean-Philippe
JP
IRD UR010, Team Mother's and Child's Health in Tropical Environment, Institut de Recherche pour le Développement, La Paz, Bolivia. jean-philippe.chippaux@ird.fr
Clavijo
Alejandra N Salas
AN
Santalla
Jose A
JA
Postigo
Jorge R
JR
Schneider
Dominique
D
Brutus
Laurent
L
D000913:Antibodies, Protozoan / Q000097:blood*; D014355:Chagas Disease / Q000151:congenital* / Q000188:drug therapy / Q000276:immunology / Q000635:transmission; D004305:Dose-Response Relationship, Drug; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007231:Infant, Newborn; D018445:Infectious Disease Transmission, Vertical; D009593:Nitroimidazoles / Q000008:administration & dosage / Q000627:therapeutic use*; D018512:Parasitemia / Q000188:drug therapy / Q000276:immunology; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious; D016896:Treatment Outcome; D014344:Trypanocidal Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D014349:Trypanosoma cruzi / Q000276:immunology*
D000913:Antibodies, Protozoan; D009593:Nitroimidazoles; D014344:Trypanocidal Agents; C009999:benzonidazole