Iron Superoxide Dismutase (Fe-SODe) as a sensitive antigenic marker for serodiagnosis of Leishmania spp. in urban schoolchildren of Central Mexico.

Leishmaniasis remains a neglected tropical disease with significant diagnostic challenges due to serological cross-reactivity with other trypanosomatids. This study evaluated the diagnostic performance of Iron Superoxide Dismutase (Fe-SODe), an excreted enzyme from Leishmania spp., as a specific antigen in detecting anti-Leishmania antibodies in school-aged children from urban areas of Santiago de Querétaro, Mexico. A total of 131 blood samples were analyzed using ELISA and Western blot assays with Fe-SODe from L. mexicana, L. braziliensis, and L. infantum. ELISA-FeSODe revealed seroprevalences of 22.1 % (L. mexicana), 14.5 % (L. braziliensis), and 9.9 % (L. infantum), while Western blot confirmed slightly higher rates. The sensitivity and specificity of ELISA-FeSODe ranged from 82.4 % to 98.5 % and 95.6 % to 100 %, respectively. The Fe-SODe ELISA and IEF immunoblot demonstrated high specificity without detectable cross-reactivity with other kinetoplastids, supporting Fe-SODe as a robust species-specific antigen for serodiagnosis.