The Leprosy Neuropathy

The peripheral neuropathy of leprosy is classified as a multineuropathy. It starts as a demyelinating process and evolves to axonal damage. All three components of the peripheral nervous system are affected: sensory, motor, and autonomic. Sensory loss causes anesthesia, analgesia, and inability to discriminate hot and cold. Motor deficit causes muscle weakness, paralysis, and atrophy. Damage to autonomic nerve fibers impairs sweating and causes dry skin. Nerve damage is directly caused by leprosy and is called primary impairment. The complications that result from nerve damage, e.g., ulcers, contractures, bone destruction, and shortening of fingers and toes, are called secondary impairments and may lead to a variety of disabilities and handicaps. Accurate neurological examination includes testing for loss of sensation on skin lesions, palpation of the peripheral nerves of predilection, and evaluation of sensory function and muscular strength. In leprosy, virtually all peripheral nerves may be involved, but those that supply the face, eyes, hands, and feet need major attention and systematic evaluation.