NDP and leprosy: All three M. leprae antigens (LID-1, NDO-LID and ND-O-BSA) were able to discriminate the MB group from all other leprosy and non-leprosy groups and the PB leprosy group from the non-leprosy EC groups, whereas only NDO-LID was able to discriminate the PB leprosy group from the non-leprosy HHC group.