Hereditary neuropathy with liability to pressure palsies mimicking multifocal compression neuropathy.

Hereditary neuropathy with liability to pressure palsies (HNPP) is a recurrent disorder of the peripheral nervous system characterized by reversible episodes of sensorimotor deficits after neural compression injuries. Also known as tomaculous neuropathy, HNPP is further characterized ultrastructurally by multiple focal thickenings (tomacula) of peripheral myelin and has an autosomal dominant inheritance. The neuropathology of HNPP includes a partial deletion encoding the peripheral myelin protein 22 (PMP-22) gene on chromosome 17, resulting in underexpression of PMP-22. We describe multiple compression mononeuropathies in an individual with HNPP and report neuropathologic findings in 2 clinically asymptomatic family members. Diagnosis was confirmed using pulsed-field gel electrophoresis. We believe that this diagnosis is clinically underappreciated by hand surgeons and should be considered in the differential diagnosis of patients with atypical presentations of compression neuropathies.