Musculoskeletal symptoms are not infrequent in leprosy and, when inaugural, may be difficult to differentiate from other conditions, most notably rheumatoid arthritis. We report the case of a 24 year-old man with a 5 year history of intermittent inflammatory arthritis and fever. Physical findings and radiographs were normal initially. Several years later, he had severe wasting of the hand muscles, stocking-glove sensory loss, burn scars on the hands, and plantar ulcers. Electrophysiological test results indicated sensory-motor neuropathy with predominant demyelination. Laboratory tests showed inflammation without immunological abnormalities. A prominent endoneurial inflammatory infiltrate composed of mononuclear cells was seen on a nerve biopsy specimen, suggesting leprosy. A family study then revealed that the patient's aunt had been diagnosed with leprosy. Dapsone, clofazimine, and rifampin were given. The joint manifestations and laboratory tests for inflammation improved. However, no changes were noted in the neurological symptoms.