title: Histology of the Mitsuda reaction of healthy adults with no known contacts with leprosy patients.
abstract: Mitsuda tests were performed on 100 healthy adult Brazilian males unrelated consanguineously to leprosy patients and with no known contacts with this disease. Three lepromatous patients served as negative Mitsuda controls. The lepromin employed was from Mycobacterium leprae-infected armadillo tissue prepared according to WHO standards. Clinical response to the lepromin inoculation was graded according to the recommendations of the VI International Leprosy Congress held in Madrid (1953). The histological reaction was graded according to the authors' criteria based on the intensity of the granulomatous response. The clinically positive (77), the doubtful (19), and 1 out of 4 clinically negative Mitsuda reactors disclosed histologically positive reactions of different degrees of intensity. A significant association between the clinical and histological readings of the Mitsuda reaction was demonstrated when the results of both readings were grouped in two classes: negative and non-negative. However, the different degrees of the histologically positive lepromin reactions were distributed at random among the clinically positive Mitsuda reactors. The frequency of histologically negative Mitsuda reactors observed among the healthy subjects who had no known contacts with leprosy patients (3%) was significantly low when compared to the frequencies reported in the pertinent literature concerning healthy contacts of patients with Hansen's disease.
mesh_terms: D000328:Adult; D006644:Histiocytes / Q000276:immunology; D006801:Humans; D006968:Hypersensitivity, Delayed / Q000276:immunology*; D007916:Lepromin / Q000276:immunology*; D007918:Leprosy / Q000276:immunology / Q000635:transmission; D008297:Male; D010587:Phagocytosis; D012867:Skin / Q000276:immunology
chemical_list: D007916:Lepromin