Synonyms: Leprosy; Elephantiasis Graecorum; Leontiasis; Satyriasis.
Leprosy is a chronic infectious disease caused by Bacillus leprae, of which the most prominent and typical symptoms are nodular lesions in the skin and mucous membranes (Lepra tuberosa), and sensory disturbances due to infiltration of the peripheral nerves (Lepra anaesthetica). The two sets of symptoms are usually combined, though one may greatly predominate. The first skin lesions are, as a rule, coin-sized or larger, dusky patches which may be either hypersensitive or numb, and usually become pigmented and slightly infiltrated.
The favorite location of the tubercles is on the face. The face generally acquires a characteristic morose, frowning expression (Facies leonina) from the thickening fo the eyebrows and facial folds and deepening of the natural furrows. The lips and ears are often irregularly thickened and prominent. The eybrows and lashes fall out. Nodules frequently spread over the cornea, causing blindness (Pannus leprosus). In the skin the leprous nodes may remain unchanged for an indefinite time, usually a few are absorbed and the more exposed ones ulcerate. Infiltrations are commonly present early in the disease in the mucous membrane of the mouth and upper respiratory tract. Thickening of the vocal cords gives the voice a raucous quality. The nasal septum may be perforated, but the bones remain intact. The nasal discharge is a common vehicle for infection.
Compression and destruction of nerve fibres are responsible for hypersensitive areas which soon become numb, for atrophy and contracture of the muscles of the hands and feet, and for the wasting of the tissues of the fingers and toes. Painless ulcers form spontaneously or as the result of injuries, and often increase and hasten the mutilation. The average duration of life of tubercular lepers is eight to ten years, of anesthetic lepers twelve to twenty years.