Positive IFN-γ enzyme-linked immunosorbent spot (ELISPOT) responses were recorded in benznidazole-stimulated wells in the range of 2 to 40 μg/mL pure benznidazole in the subject with dermatitis (Fig. 2A and C), whereas no benznidazole-reactive cells were found in the subject without dermatitis (Fig. 2B). The gene discussed is IFNG; the disease is dermatitis.