causes
Leprosy is caused by the organism Mycobacterium leprae. It is not very contagious and has a long incubation period, which makes it difficult to determine where or when the disease was contracted. Children are more gullible than adults to contracting the disease. Leprosy has two common forms, tuberculoid and lepromatous. Both forms produce sores on the skin, but the lepromatous form is most severe, producing large, disorted lumps and bumps. All forms of the disease eventually cause nerve damage in the arms and legs, which causes sensory loss in the skin and muscle weakness. People with long-term leprosy may lose the use of their hands or feet due to continued injury resulting from lack of sensitivity. Leprosy is common in many countries worldwide, and in temperate, tropical, and subtropical climates. Approximately 100 cases per year are diagnosed in the United States. Most cases are limited to the South, California, Hawaii, and U.S. island possessions.

Symptoms
Symptoms are:

* Skin bruises that are lighter than your normal skin color * Bruises have decreased sensitivity to touch, heat, or pain * Scrapes and bruises that do not heal after several weeks or up to months * Numbness or absent sensitivity in the hands, arms, feet, and legs * Muscle weakness

Signs and tests

* lepromin skin test can be used to diagnosed lepromatous from tuberculoid leprosy, but is not used for diagnosis * Skin lesion biopsy * Skin scraping