Polyneuropathy associated with IgM monoclonal gammapathy (MG) with anti-MAG (myelin-associated-glycoprotein) activity is a demyelinating polyneuropathy characterized clinically by sensory ataxia, tremor, paresthesia, and impaired gait.

Raised, well-circumscribed areas of erythema and edema involving the dermis and epidermis. Urticaria is intensely pruritic, and blanches completely with pressure.