Present day knowledge of the diagnosis of the early stages of leprosy is still deficient. This fact explains the many attempts which have been and are still being made to resolve the complexity of the problem. The long and uncertain incubation period, which is devoid of specific clinical symptoms, makes this task even more difficult. While the situation is far easier in lepromatous leprosy, the neural type in its early manifestation is often a clinical puzzle. Various laboratory methods have been devised for this reason, among them the lepromin test.
The lepromin test was first used by Mitsuda in 1916 in Zensei Hospital, near Tokyo, Japan, in the investigation of the leprosy problem. The term leprolin was introduced by Rost for a preparation similar to old tuberculin, prepared from a bacillary bouillon culture. The term leprolin test was changed by Bargehr to lepromin test not only to avoid confusion with