Neuropathy associated with cryoglobulinemia.

A patient with severe subacute sensory ataxia was found to have an IgM (kappa) cryoglobulin. Clinical, electrophysiologic, and sural nerve biopsy studies indicated that axonal degeneration and segmental demyelination both played a role in the pathogenesis of this neuropathy. Corticosteroid therapy was associated with notable clinical improvement and a 50% decrease in cryoglobulin concentration.