Polyneuropathy-hearing loss-ataxia-retinitis pigmentosa-cataract syndrome

Definition

A rare neurologic syndrome with peripheral neuropathy characterized by polyneuropathy, hearing loss, ataxia, retinitis pigmentosa, and cataracts. Polyneuropathy presents with slowly progressive and often demyelinating sensorimotor neuropathy where pes cavus, decreased sensation and hyporeflexia may appear as early signs. Hearing loss is progressive, usually bilateral and presents with childhood/early adolescent-onset whereas patients develop retinis pigmentosa and cataracts (typically posterior subcapsular) often in early to mid-adulthood. Ataxia may manifest with gait instability/spasticity, dysarthria, intention tremor and dysmetria of the limbs. Additional clinical features may include tendon abnormalities, hyperreflexia, extensor plantar responses. Seizures and mild intellectual disability is reported in few patients.