[Ocular histopathological studies in leprosy in the silent stage--I. Light microscopic feature]

Eyes from autopsy cases of leprosy patients (29 eyes from 16 cases) were examined histologically. In some cases immunohistochemical methods were used. In the lepromatous type, ocular complications such as keratitis and iridocyclitis were often found. In the tuberculoid type, such complications were seldom encountered. In the active stage, lepra cells and "foamy cells" showed positive reaction to acid-fast staining and anti-BCG antibody but in the silent stage they did not react. All foamy cells in both the active and the silent stage showed positive reaction to KP1, but they did not react to lysozyme or alpha 1-antitrypsin. These results suggest that the foamy cells originated from macrophages, but that their biological activity was low.