Hereditary Neuropathy With Liability to Pressure Palsies: Diverse Phenotypes in Childhood

Hereditary neuropathy with liability to pressure palsies (HNPP) is a rare autosomal-dominant disorder that most commonly produces recurrent painless focal sensory and motor neuropathies often preceded by minor, mechanical stress, or minor trauma. Herein, we report 2 pediatric cases of HNPP with atypical presentations; isolated muscle cramping and toe walking. Electrophysiologic testing disclosed multifocal sensorimotor polyneuropathy with slowing of sensory conduction velocities in both cases, which prompted PMP 22 gene deletion testing. Multifocal sensorimotor electrophysiologic abnormalities, with slowing of sensory conduction velocities should raise consideration of HNPP in childhood. These case reports emphasize that the diagnosis of HNPP in children requires a high index of suspicion.