Leprosy is an infectious disease caused by Mycobacterium leprae, a bacterium that infects Schwann cells in the peripheral nervous system and macrophages in the skin. Leprosy presents primarily as a peripheral neuropathy but may lead to deformities if it progresses without treatment. Leprosy cases are classified as paucibacillary if the patient has 5 or fewer skin lesions and low bacterial counts or as multibacillary if the patient has more than 5 lesions and high bacterial counts. The complexity of clinical presentations has hindered the development of an easy diagnostic test.