On-line version ISSN 0717-7712
FABBRO, DIANA et al. ASSESSMENT OF ELISA F29 AS A MARKER OF ETIOLOGICAL TREATMENT EFFICACY FOR CHAGAS DISEASE. Parasitol. latinoam. [online]. 2007, vol.62, n.3-4, pp. 103-111. ISSN 0717-7712. doi: 10.4067/S0717-77122007000200001.
A transversal study was performed on sera from chronic chagas ic patients treated with nifurtimox (Nx) or benznidazole (Bz), in order to evaluate the Trypanosoma cruzi flagellar calcium-binding protein (F29) as a marker for therapeutic effectiveness. An ELISA was used with these F29 recombinant antigen, and its relation to conventional serology (CS) and parasitological and clinical evolution was analysed. Sera from 118 patients with retrospective, serological, parasitological and clinical information was available, were analyzed. Patients were grouped into: A) 30 treated patients whose CS became negative after treatment; B) 34 treated patients whose CS remained positive; C) 54 untreated patients. A double-blind trial was conducted simultaneously in all serum samples, by means ofCS (indirect hemagglutination, direct agglutination and indirect immunofluorescence) and ELISA F29. The ELISA F29 test was non reactive in: 100% of group A, 82.4% of group B and 13%> of group C. The infected patients who presented electrocardiographic alterations compatible with chronic chagasic myocardiopathy (n = 11) were reactive for ELISA F29. All patients whose parasitological studies (xenodiagnosis and/or strout method) were positive presented a high reactivity to the ELISA F29 test. The correlation between ELISA F29 and CS was statistically significant (p < 005) in the treated group whose CS was non reactive (group A) and the untreated group (group C). As opposed to this, in the group of treated patients whose CS remained positive (group B), the ELISA F29 test was reactive only in a 17.6%>. These results suggest that the fast and user-friendly ELISA F29 test could be useful to monitor changes after trypanocidal treatment.
Keywords : Chagas disease; serological marker of therapeutic efficacy.