Comparison of reactions to human and armadillo lepromins in leprosy.

To assess the usefulness of Mycobacterium leprae-infected armadillo tissue as a substitute for human lepromas for the manufacture of lepromin, we compared skin reactions to preparations from these two sources in 115 leprosy patients. The patient sample represented all the primary clinical forms of leprosy. Lepromin derived from the armadillo (lepromin-A) provoked the same pattern of responses as human derived lepromin (lepromin-H), i.e., lepromatous patients gave the weakest reactions. Lepromin-A reactions were consistently more intense than those to lepromin-H. We conclude that lepromin-A is a promising alternative to lepromin-H and may make the worldwide distribution of a standardized skin testing reagent feasible.