title: IgG4-related neuropathy: a case report.
abstract: OBJECTIVE
  The newly recognized entity IgG4-related disease (IgG4-RD) is characterized by an elevated IgG4 serum concentration and tissue infiltration by IgG4-positive plasma cells. We describe, for the first time, the clinical features and nerve biopsy findings of a patient with IgG4-RD who presented with neuropathy in the extremities.
  
  
  METHODS
  A 55-year-old man had histopathologically defined IgG4-RD that manifested as sensory-motor neuropathy. The neuropathic features were multiple mononeuropathies with electrophysiological findings suggestive of axonal neuropathy. Marked thickening with abundant collagen fibers and infiltration of IgG4-positive plasma cells were observed in the epineurium of the biopsied sural nerve. A moderate degree of myelinated fiber loss without evidence of segmental demyelination was present, whereas necrotizing vasculitis was not found. Oral prednisolone therapy ameliorated the neuropathic symptoms.
  
  
  CONCLUSIONS
  This case of IgG4-RD presented as sensory-motor neuropathy with pain and sclerosis of the skin in the extremities. The differential diagnosis of neuropathy should include IgG4-RD.
authors: Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya, Japan.
authors: Ken
authors: K
authors: Ohyama
authors: Haruki
authors: H
authors: Koike
authors: Masahiro
authors: M
authors: Iijima
authors: Rina
authors: R
authors: Hashimoto
authors: Minoru
authors: M
authors: Tomita
authors: Yuichi
authors: Y
authors: Kawagashira
authors: Akira
authors: A
authors: Satou
authors: Shigeo
authors: S
authors: Nakamura
authors: Gen
authors: G
authors: Sobue
mesh_terms: D000893:Anti-Inflammatory Agents / Q000627:therapeutic use; D015703:Antigens, CD / Q000378:metabolism; D001706:Biopsy; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood / Q000378:metabolism*; D008214:Lymphocytes / Q000145:classification / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009431:Neural Conduction; D010265:Paraproteinemias / Q000097:blood / Q000150:complications* / Q000188:drug therapy; D010523:Peripheral Nervous System Diseases / Q000097:blood* / Q000150:complications* / Q000188:drug therapy; D011239:Prednisolone / Q000627:therapeutic use; D012598:Sclerosis / Q000473:pathology; D012867:Skin / Q000378:metabolism / Q000473:pathology
chemical_list: D000893:Anti-Inflammatory Agents; D015703:Antigens, CD; D007074:Immunoglobulin G; D011239:Prednisolone