Clinical and laboratory features of neuropathies with serum IgM binding to TS-HDS

Introduction: In this investigation we studied clinical and laboratory features of polyneuropathies in patients with serum IgM binding to the trisulfated disaccharide IdoA2S‐GlcNS‐6S (TS‐HDS). Methods: We retrospectively compared 58 patients with selective IgM binding to TS‐HDS to 41 consecutive patients with polyneuropathies without TS‐HDS binding. Results: Patients with IgM vs. TS‐HDS commonly had distal, sensory, axonal neuropathies. Weakness was associated with IgM M‐proteins. Hand pain and serum IgM M‐proteins were more common than in control neuropathy patients. TS‐HDS antibody binding was often selectively κ class. Biopsies showed capillary pathology with thickened basal lamina and C5b9 complement deposition. IgM in sera with TS‐HDS antibodies often bound to capillaries. Conclusions: Serum IgM binding to TS‐HDS is associated with painful, sensory > motor, polyneuropathies with an increased frequency of persistent hand discomfort, serum IgM M‐proteins, and capillary pathology. Serum IgM binding to TS‐HDS suggests a possible immune etiology underlying some otherwise idiopathic sensory polyneuropathies. Muscle Nerve 45: 866–872, 2012