title: No negative impact of serum IgG4 levels on clinical outcome in 435 patients with primary sclerosing cholangitis from Japan.
abstract: BACKGROUND
  Several studies have demonstrated that elevated serum IgG4 levels are associated with poor outcomes of primary sclerosing cholangitis (PSC), but the impact of serum IgG4 levels on PSC remains controversial. In this study, we aimed to determine prognostic factors of patients with PSC and to investigate the association between serum IgG4 levels and the clinical features and prognosis of PSC in a Japanese cohort.
  
  
  METHODS
  We retrospectively analyzed follow-up data for 435 patients with PSC (UMIN000018438). Patients with distinct etiologies of sclerosing cholangitis including IgG4-related sclerosing cholangitis (IgG4-SC) were excluded from this study.
  
  
  RESULTS
  Serum IgG4 levels were tested at the time of diagnosis in 216 of 435 patients with PSC, and were elevated in 27 patients (>134 mg/dl, 12.5%). Clinical features at diagnosis were comparable between patients with normal and elevated serum IgG4 levels, with the exception of serum albumin. The overall and liver-transplantation free survival rate was comparable between the groups. Multivariate analysis indicated that age, albumin, and bilirubin, but not IgG4, at the time of diagnosis affected PSC prognosis.
  
  
  CONCLUSIONS
  The current study showed that serum IgG4 levels at diagnosis do not affect PSC prognosis in a Japanese cohort that excluded patients with IgG4-SC.
authors.affiliation: Department of Medicine, Teikyo University School of Medicine, 2-11-1 Kaga, Itabashi-ku, Tokyo, 173-8605, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Tanaka
authors.affiliation: Department of General Medicine, Hiroshima University, Graduate School of Medical Science, Programs of Applied Medicine, Clinical Pharmacotherapy, Hiroshima, Japan.
authors.forename: Susumu
authors.initials: S
authors.lastname: Tazuma
authors.affiliation: Department of Gastroenterology, Japanese Red Cross Nagoya Daini Hospital, Nagoya, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Nakazawa
authors.affiliation: Department of Gastroenterology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Isayama
authors.affiliation: Department of Medicine and Clinical Oncology, Graduate School of Medicine, Chiba University, Chiba, Japan.
authors.forename: Toshio
authors.initials: T
authors.lastname: Tsuyuguchi
authors.affiliation: Department of Internal Medicine, Second Teaching Hospital, Fujita Health University, Nagoya, Japan.
authors.forename: Kazuo
authors.initials: K
authors.lastname: Inui
authors.affiliation: Department of Medicine, Teikyo University School of Medicine, 2-11-1 Kaga, Itabashi-ku, Tokyo, 173-8605, Japan.
authors.forename: Hajime
authors.initials: H
authors.lastname: Takikawa
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D015415:Biomarkers / Q000097:blood; D015209:Cholangitis, Sclerosing / Q000097:blood* / Q000401:mortality* / Q000503:physiopathology; D015331:Cohort Studies; D018450:Disease Progression; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D007564:Japan; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies; D018570:Risk Assessment; D012720:Severity of Illness Index; D012737:Sex Factors; D011795:Surveys and Questionnaires; D016019:Survival Analysis; D013997:Time Factors
chemical_list: D015415:Biomarkers; D007074:Immunoglobulin G
keywords: IgG4-related disease; IgG4-related sclerosing cholangitis; Liver transplantation