Cutaneous manifestations of neurological diseases: review of neuro-pathophysiology and diseases causing pruritus.

Pruritus does not always originate from stimulation to the skin associated with primary dermatological disorders. It may be caused by neurological or behavioural disorders. The essential role of the nervous system in the control (enhancement and inhibition) of pruritus and its pathophysiology are presented. In order to allow differentiation between dermatological and neurological disorders, inherited or acquired peripheral neuropathies and central nervous disorders (Arnold-Chiari syndrome, seizure-related disorders, central nervous system tumours) that may induce itch are discussed.