Different clinical, electrophysiological and immunological features of CIDP associated with paraproteinaemia.

Chronic inflammatory demyelinating polyneuropathy (CIDP) is frequently associated with monoclonal gammopathies of undetermined significance (MGUS), Waldenström disease and osteosclerotic myeloma. There are still controversies about the role of these paraproteinaemias in determining the clinical features and the response to treatment of CIDP. We review the clinical, electrophysiological and immunological features and the response to treatment of patients with CIDP associated with paraproteinaemias. The available literature suggest some conclusions: presence of antimyelin-associated glycoprotein (MAG) antibody (Ab) identifies patients with mainly sensory CIDP and low response to treatment; CIDP associated with IgM-paraproteinaemia without anti-MAG Ab probably are similar to CIDP not associated with paraproteinaemia as well as CIDP with IgG- or IgA-MGUS; however, some patients with IgA-MGUS can show features similar to CIDP with IgM paraproteinaemia and anti-MAG Ab. Low response to immunomodulating treatment in patients with mainly motor CIDP should prompt a careful research of an underlying osteosclerotic myeloma.