Chronic polyradiculoneuro-pathies responsive to immunotherapy do not necessarily show electrophysiologic-al or nerve biopsy evidence of demyelination.

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) remains one of the most satisfying disorders to diagnose since many patients respond well to therapy, and even severely disabled patients may return to normal productive life. This diagnosis is therefore always considered in the investigation of chronic neuropathies. The cardinal feature in diagnosing CIDP has been the demonstration, in the appropriate clinical setting, of electrophysiological features of demyelination. In this issue, Oh et al ,1 page…… describe 33 patients with chronic neuropathy in whom no evidence of demyelination was found by electrophysiology or nerve biopsy but rather features of axonal degeneration, yet all responded to immunotherapy. The patients were …