Use of eluates of filter paper blood spots in ELISA for the serodiagnosis of leprosy.

ABSTRACT

Blood samples were collected from 59 leprosy patients and 35 normal healthy subjects by veni-puncture and finger prick methods to obtain serum samples and blood spots on filter paper respectively. The serum samples at 1300 dilutions and the eluates of dried blood spots at 140, 180, 1160 and 1320 dilutions were applied in ELISA to measure the antibody levels (IgM) against synthetic ND-O-BSA antigen. The antibody levels were found to be high in the multibacillary leprosy patients than the pauci-bacillary patients irrespective of whether serum samples or eluates were used. The OD values obtained at 1160 dilution of the eluates were equivalent to that of values obtained at 1300 dilution of the serum samples. The positivities differ in different dilution of the eluates, showing the highest in the 140 dilution and the lowest in the 1320 dilution.