HEREDITARY NEUROPATHY WITH PREDISPOSITION TO PRESSURE PALSIES
This is an autosomal dominant hereditary condition in which patients develop numbess and muscular weakness following nerve compression or minor trauma. The patients often manifest compression neuropathies such as carpal tunnel syndrome. Electrodiagnostic testing reveals prolonged motor distal latencies with slow conduction velocities. Histopathologic findings characteristically show segmental demyelination of the nerves with remyelination creating tomacula (sausage shaped thickenings of the myelin sheaths). Blood sample testing for genetic abnormalities of chromosome 17 demonstrating the deletion of peripheral nerve myelin protein 22 (PMP-22) is diagnostic. There is no therapy to be offered; therefore, patients should be counseled to avoid traumatic physical activities.