Neuropathy leprosy

Peripheral neuropathies maybe widely disseminated or focal. Patients with disseminated polyneuropathy, whether demyelinative or axonal, usually demonstrate distal sensory and/or motor impairment. Multifocal neuropathy, also referred to as mononeuropathy multiplex, is often a consequence of lesions affecting the vasa nervorum, the blood vessels that supply peripheral nerves. The most common diseases to compromise the vasa nervorum and cause infarction of nerve fascicles are diabetes mellitus and periarteritis nodosa. Other frequent causes of mononeuropathy multiplex include infection (e.g. Lyme disease and leprosy) and multiple compression injury (e.g. bilateral carpal tunnel syndrome). When mononeuropathy... 

The lepromatous form of leprosy is characterized by loss ofcutaneoussensibility. Hansen sbacillus(Mycobacterium leprae), which proliferates only in environments cooler than the core temperature maintained by most mammals, is capable of infecting Schwann cells in subcutaneous nerves because the basal lamina of these cells contains a-dystroglycan, to which this mycobacterium binds, and because subcutaneous nerves are often cooler than deeper tissues. Lepromatous neuropathy is a common cause of sensory mononeuropathy multiplex in the developing World [16,17]. 

Dapsone-induced neuropathy is not common (14), in spite of its widespread use in a variety of unrelated disorders. It has not been reported in patients with leprosy, but it would be easy to miss, since worsening neuropathy would readily be attributed to the underlying disease. 

Neuropathy has not been reported in patients with leprosy taking the usually recommended dosage of 100 mg/day. Isolated cases of dapsone-induced peripheral neuropathy, including motor and minor sensory defects, have been published (15,16). The clinical characteristics include a motor neuropathy affecting the extremities with onset within 5 years after the start of dapsone therapy in doses of over 300 mg/day. Complete recovery from the neuropathy almost always occurs after the dose is reduced or the drug is withdrawn. 

The incidence of peripheral neuropathy, with sjmmetrical painful paresthesia of the hands and feet often accompanied by sensory loss in the legs, seems to vary with the condition that is being treated, and ranges from under 1% in patients with leprosy to over 70% in patients with prurigo nodularis (41,52). The symptoms do not correlate with either the duration of treatment or the dose. Women and elderly people seem to have an increased risk of neuropathy (53). 

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