Development and Application of an ELISA Assay Using Excretion/Secretion Proteins from Epimastigote Forms of T. cruzi (ESEA Antigens) for the Diagnosis of Chagas Disease

Table 2

Mean, standard deviation (SD), optical density range (OD), and specificity estimates for serum groups in ELISAs based on secreted and excreted antigen homogenates (ESEA antigens) from trypomastigote forms of T. cruzi.

Group of individuals	Mean (OD) ± SD	Range DO; min–max	Sp %; (DO 0,500)	Sens %; (DO 0,500)	Sp %; (DO 0,600)	Sens %; (DO 0,600)
Individuals negative for T. cruzi infection (n = 50)	0.339 ± 0.222	0.073–1.129	80	—	88	—
Chagas-positive individuals; (n = 50)	1.099 ± 0.323	0.474–1.888	—	98	—	98
Leishmaniasis-positive individuals (n = 10)	0.617 ± 0.244	0.370–1.137	30	—	60	—
Individuals-positive for other parasitic diseases (n = 10)	0.492 ± 0.275	0.205–0.921	50	—	60	—

OD: optical density; SD: standard deviation; min: minimum, max: maximum; Sens: sensitivity; Sp: specificity.