[Subclinical neuropathies and paraproteinemias]

The relationship between monoclonal gammapathies and peripheral nerve involvement is well known. The pathogenesis of neuropathy has been ascribed to infiltrative, compressive, ischemic or haemorrhagic phenomena, to an amyloid storage or to antibody autoaggression toward neural antigens. Forty-five patients suffering from monoclonal gammapathy of uncertain significance (MGUS), multiple myeloma (MM), MG IgM, were submitted to a neurophysiological examination. 10 pts. were excluded because of neurotoxic drugs, diabetes or alcohol abuse. The investigation included SCV of median, ulnar, and sural n., MCV and F wave of peroneal n., H reflex, and computerized analysis of recruitment pattern. A subclinical neuropathy was found in 11 of 35 pts. (30%) without any neurological symptom. A CTS was found in 4 patients. The high rate of subclinical neuropathy in asymptomatic pts. is underlined by the Authors, while the presence of subclinical neuropathy in cases of MGUS needs further studies.