title: Mononeuritis multiplex with tumefactive cellular infiltration in a patient with reactive lymphoid hyperplasia with increased immunoglobulin G4-positive cells.
abstract: We describe a 54-year-old man with mononeuritis multiplex and reactive lymphoid hyperplasia with increased immunoglobulin G4 (IgG4)-positive cells. Asymmetrical numbness and weakness had advanced stepwise for 6 years. Serum immunoglobulin G, IgG4, and immunoglobulin E levels were elevated, whereas M protein was not detected. Chest and abdominal computed tomography showed generalized lymphadenopathy. Inguinal lymph node biopsy revealed expansion of the interfollicular area with infiltration of IgG4-positive cells, of which the absolute number was greater than 100 per high-power field, and the percentage of IgG4+/immunoglobulin G+ plasma cells was 33%. Sural nerve biopsy disclosed axonal neuropathy with tumefactive lymphoid infiltrate in epineurium, but IgG4-positve plasma cells and fibrosis were not detected. Symptoms and laboratory data were improved with oral glucocorticoid therapy at a dose of 0.6 mg/kg per day. Although the causal mechanisms of neuropathy should be determined in future studies, peripheral nerve involvement may occur in patients with reactive lymphoid hyperplasia with increased IgG4-positive cells.
authors.affiliation: Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya466-8550, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Yokoi
authors.affiliation: Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya466-8550, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Kawagashira
authors.affiliation: Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya466-8550, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Ohyama
authors.affiliation: Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya466-8550, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Iijima
authors.affiliation: Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya466-8550, Japan.
authors.forename: Haruki
authors.initials: H
authors.lastname: Koike
authors.affiliation: Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya466-8550, Japan.
authors.forename: Hirohisa
authors.initials: H
authors.lastname: Watanabe
authors.affiliation: Department of Pathology, Nagoya University Graduate School of Medicine, Nagoya466-8550, Japan.
authors.forename: Akiko
authors.initials: A
authors.lastname: Tatematsu
authors.affiliation: Department of Pathology, Nagoya University Graduate School of Medicine, Nagoya466-8550, Japan.
authors.forename: Shigeo
authors.initials: S
authors.lastname: Nakamura
authors.affiliation: Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya466-8550, Japan. Electronic address: sobueg@med.nagoya-u.ac.jp.
authors.forename: Gen
authors.initials: G
authors.lastname: Sobue
mesh_terms: D001706:Biopsy; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D008206:Lymphatic Diseases / Q000473:pathology; D008297:Male; D008875:Middle Aged; D020422:Mononeuropathies / Q000473:pathology*; D010950:Plasma Cells / Q000378:metabolism; D019310:Pseudolymphoma / Q000473:pathology*
chemical_list: D007074:Immunoglobulin G
keywords: IgG4-related disease; Lymphadenopathy; Neuropathy; Steroid