Monoclonal gammopathy of undetermined significance (MGUS, unknown or uncertain may be substituted for undetermined) or benign monoclonal gammopathy is a condition in which a low or non-quantifiable level of a
monoclonal paraprotein is detected in the blood by means of
protein electrophoresis. In addition, some patients develop a
polyneuropathy (damage to peripheral nerves) or other problems related to the secreted antibody. MGUS is distinct from
multiple myeloma, as described below.
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