Immune-mediated chorea in a patient with kappa light-chain monoclonal gammopathy

The objective of this paper was to report on a case of steroid-responsive chorea in a patient with κ light-chain monoclonal gammopathy. In addition to subacute-onset generalized chorea, evidence of peripheral neuropathy in this elderly gentleman led us to investigate for paraproteinemia. We treated the patient with intravenous steroids in view of elevated κ light-chain assay and bone marrow biopsy, suggestive of monoclonal gammopathy of undetermined significance. There was a remarkable improvement of paresthesias and chorea at 6 months follow-up with no evidence of evolution to malignancy at 1 year. Autoimmune chorea is a treatable condition if identified and treated timely.