The histopathologic diagnosis of leprosy

The objective of this paper is to encourage histopathologists to recognize and diagnose leprosy so that it can be treated effectively at the earliest stage possible, before irreversible deformities result. Recognition of the earliest form of leprosy-indeterminate-is emphasized. Histopathologic descriptions are made and illustrated for the principal types of leprosy. Emphasis is placed on (1) the need for dependable acid-fast staining of leprosy bacillus, (2) the non-specific infiltrate in indeterminate leprosy, and (3) the involvement of nerves in all types of leprosy.