title: Hyperviscosity-induced dementia.
abstract: Dementia was the presenting symptom in a patient with increased serum viscosity secondary to multiple myeloma. Plasmapheresis led to complete resolution of the neurologic syndrome. Serum hyperviscosity should be added to the growing list of reversible causes of dementia. When hyperviscosity-associated dementia is suspected, both serum and whole blood viscosity determinations are indicated.
mesh_terms: D000368:Aged; D001809:Blood Viscosity; D003704:Dementia / Q000097:blood*; D006402:Hematologic Diseases / Q000209:etiology; D006801:Humans; D008297:Male; D009101:Multiple Myeloma / Q000150:complications