Evaluation of a Novel Tc-24 Recombinant Antigen ELISA for Serologic Detection of Trypanosoma cruzi Infection in Dogs: A Pilot Study.

Chagas disease, caused by the protozoan Trypanosoma cruzi, is a significant challenge for canine health, with limited diagnostic tools. This study assessed the performance of a novel Tc-24 recombinant antigen ELISA compared to three commercial diagnostic tests on 70 serum samples from kennel dogs in Texas. The Tc-24 ELISA demonstrated high sensitivity (87.5%) and specificity (91.2%) compared to Indirect Fluorescent Antibody (IFA) testing, with significant differences in Tc-24 optical density (OD) between positives and negatives (0.607 vs. 0.089, p < 0.001). When compared to Chagas Stat-Pak (SP), Tc-24 ELISA showed sensitivity and specificity values of 82.1% and 86.7%, respectively (p < 0.001). For Chagas Detect Plus (IB), the assay achieved a sensitivity of 80.0% and specificity of 93.1% (p < 0.001). Spearman correlation analysis revealed significant associations between Tc-24 OD and SP (r = 1.0, p = 0.0167), IB (r = 0.9, p = 0.0833) and IFA (r = 0.6273, p = 0.044). Elevated immunochromatographic values in commercial kits (SP or IB) correlated with Tc-24 OD (1.17 vs. 0.039, p < 0.001), achieving 100% sensitivity and 95.8% specificity based on positive results from commercial kits. These findings suggest that Tc-24 ELISA is a reliable and accurate serological tool for diagnosing T. cruzi infection in dogs, with the potential to enhance diagnostic capabilities in veterinary medicine.