title: Idiopathic retroperitoneal fibrosis associated with IgG4-positive-plasmacyte infiltrations and idiopathic chronic pancreatitis.
abstract: Idiopathic retroperitoneal fibrosis (IRPF) is an inflammatory fibrosclerosing condition, leading to renal failure by obstruction of the ureters. Idiopathic chronic pancreatitis associated with marked inflammatory infiltrates has recently been referred to as autoimmune pancreatitis (AIP), and infiltrating plasmacytes carrying immunoglobulin-gamma type 4 (IgG4) are relevant to its pathogenesis. The case is described herein of IRPF associated with subclinical pancreatitis that was most probably AIP in a 70-year-old man. Biopsy specimens of the retroperitoneal pseudotumor revealed a marked lymphoplasmacytic infiltration with dense fibrosis. Infiltrating plasma cells were immunoreactive for anti-IgG4 antibodies. Subsequent systemic examinations showed an extremely elevated serum IgG4 level and pancreatitis concordant with AIP. Following oral steroid administration, the serum IgG4 level normalized, although the appearance of the pseudotumor did not alter. Some AIP cases have been associated with idiopathic fibrosclerosing disorders including IRPF, but histological evidence of IgG4-related IRPF has rarely been provided.
authors.affiliation: Department of Urology, Niigata Rousai Hospital, Joetsu, Japan.
authors.forename: Norio
authors.initials: N
authors.lastname: Miyajima
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Koike
authors.forename: Makoto
authors.initials: M
authors.lastname: Kawaguchi
authors.forename: Yo
authors.initials: Y
authors.lastname: Zen
authors.forename: Kota
authors.initials: K
authors.lastname: Takahashi
authors.forename: Noboru
authors.initials: N
authors.lastname: Hara
mesh_terms: D000368:Aged; D001327:Autoimmune Diseases / Q000150:complications / Q000276:immunology / Q000473:pathology; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology; D008297:Male; D050500:Pancreatitis, Chronic / Q000150:complications / Q000276:immunology / Q000473:pathology*; D010950:Plasma Cells / Q000276:immunology / Q000473:pathology*; D012185:Retroperitoneal Fibrosis / Q000150:complications / Q000276:immunology / Q000473:pathology*
chemical_list: D007074:Immunoglobulin G