title: A case of IgG4-related mesenteritis.
abstract: IgG4-related disease is a newly recognized fibroinflammatory condition characterized by tumefaction consisting of fibrosis with dense infiltration of IgG4-positive plasma cells; affecting various organs. A case of IgG4-related sclerosing mesenteritis is reported. A 64-year-old man was admitted to our hospital with a suspected tumor of the small intestine. Abdominal computed tomography demonstrated a 6-cm soft tissue mass in the right lower mesentery compressing the jejunum, which also showed accumulation of fluorodeoxyglucose uptake on fluorine-18 fluorodeoxyglucose positron emission tomography. With a preoperative diagnosis of suspected malignant lymphoma with lymphadenopathy in the mesentery, partial small bowel resection was performed. Macroscopically, a hard mass, including several swollen lymph nodes, was detected in the mesentery. Microscopically, marked fibrosis showing partially storiform pattern, obstructive phlebitis, follicular hyperplasia, and abundant infiltration of IgG4-positive plasma cells were detected. IgG4-related mesenteritis was diagnosed histopathologically, but the serum IgG4 level was 81 mg/dl postoperatively. Five months after the surgery, an 11-cm soft tissue mass involving the left ureter appeared. Histological examination of a biopsy specimen from the retroperitoneal mass showed fibrosis with inflammatory infiltration. Although IgG4-related retroperitoneal fibrosis could not be confirmed histologically, the tumor responded well to steroid therapy.
authors.affiliation: Department of Internal Medicine, Tokyo Metropolitan Komagome Hospital, 3-18-22 Honkomagome, Bunkyo-ku, Tokyo, 113-8677, Japan.
authors.forename: Erika
authors.initials: E
authors.lastname: Mori
authors.affiliation: Department of Internal Medicine, Tokyo Metropolitan Komagome Hospital, 3-18-22 Honkomagome, Bunkyo-ku, Tokyo, 113-8677, Japan. kamisawa@cick.jp.
authors.forename: Terumi
authors.initials: T
authors.lastname: Kamisawa
authors.affiliation: Department of Internal Medicine, Tokyo Metropolitan Komagome Hospital, 3-18-22 Honkomagome, Bunkyo-ku, Tokyo, 113-8677, Japan.
authors.forename: Taku
authors.initials: T
authors.lastname: Tabata
authors.affiliation: Department of Internal Medicine, Tokyo Metropolitan Komagome Hospital, 3-18-22 Honkomagome, Bunkyo-ku, Tokyo, 113-8677, Japan.
authors.forename: Satomi
authors.initials: S
authors.lastname: Shibata
authors.affiliation: Department of Internal Medicine, Tokyo Metropolitan Komagome Hospital, 3-18-22 Honkomagome, Bunkyo-ku, Tokyo, 113-8677, Japan.
authors.forename: Kazuro
authors.initials: K
authors.lastname: Chiba
authors.affiliation: Department of Internal Medicine, Tokyo Metropolitan Komagome Hospital, 3-18-22 Honkomagome, Bunkyo-ku, Tokyo, 113-8677, Japan.
authors.forename: Sawako
authors.initials: S
authors.lastname: Kuruma
authors.affiliation: Department of Internal Medicine, Tokyo Metropolitan Komagome Hospital, 3-18-22 Honkomagome, Bunkyo-ku, Tokyo, 113-8677, Japan.
authors.forename: Go
authors.initials: G
authors.lastname: Kuwata
authors.affiliation: Department of Internal Medicine, Tokyo Metropolitan Komagome Hospital, 3-18-22 Honkomagome, Bunkyo-ku, Tokyo, 113-8677, Japan.
authors.forename: Tomoko
authors.initials: T
authors.lastname: Onishi
authors.affiliation: Department of Internal Medicine, Tokyo Metropolitan Komagome Hospital, 3-18-22 Honkomagome, Bunkyo-ku, Tokyo, 113-8677, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Fujiwara
authors.affiliation: Department of Internal Medicine, Tokyo Metropolitan Komagome Hospital, 3-18-22 Honkomagome, Bunkyo-ku, Tokyo, 113-8677, Japan.
authors.forename: Junko
authors.initials: J
authors.lastname: Fujiwara
authors.affiliation: Department of Internal Medicine, Tokyo Metropolitan Komagome Hospital, 3-18-22 Honkomagome, Bunkyo-ku, Tokyo, 113-8677, Japan.
authors.forename: Takeo
authors.initials: T
authors.lastname: Arakawa
authors.affiliation: Department of Internal Medicine, Tokyo Metropolitan Komagome Hospital, 3-18-22 Honkomagome, Bunkyo-ku, Tokyo, 113-8677, Japan.
authors.forename: Kumiko
authors.initials: K
authors.lastname: Momma
authors.affiliation: Department of Internal Medicine, Tokyo Metropolitan Komagome Hospital, 3-18-22 Honkomagome, Bunkyo-ku, Tokyo, 113-8677, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Koizumi
authors.affiliation: Department of Surgery, Tokyo Metropolitan Komagome Hospital, Tokyo, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Matsumoto
authors.affiliation: Department of Pathology, Tokyo Metropolitan Komagome Hospital, Tokyo, Japan.
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Horiguchi
mesh_terms: D005938:Glucocorticoids / Q000627:therapeutic use; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D008297:Male; D008875:Middle Aged; D015436:Panniculitis, Peritoneal / Q000150:complications* / Q000276:immunology* / Q000601:surgery; D011239:Prednisolone / Q000627:therapeutic use; D012185:Retroperitoneal Fibrosis / Q000150:complications* / Q000175:diagnosis / Q000188:drug therapy
chemical_list: D005938:Glucocorticoids; D007074:Immunoglobulin G; D011239:Prednisolone
keywords: IgG4; Retroperitoneal fibrosis; Sclerosing mesenteritis