title: Eosinophilic cholangitis is a potentially underdiagnosed etiology in indeterminate biliary stricture.
abstract: OBJECTIVE
  To investigate presence and extent of eosinophilic cholangitis (EC) as well as IgG4-related disease in patients with indeterminate biliary stricture (IBS).
  
  
  METHODS
  All patients with diagnosis of sclerosing cholangitis (SC) and histopathological samples such as biopsies or surgical specimens at University Hospital Frankfurt from 2005-2015 were included. Histopathological diagnoses as well as further clinical course were reviewed. Tissue samples of patients without definite diagnosis after complete diagnostic work-up were reviewed regarding presence of eosinophilic infiltration and IgG4 positive plasma cells. Eosinophilic infiltration was as well assessed in a control group of liver transplant donors and patients with primary sclerosing cholangitis.
  
  
  RESULTS
  one hundred and thirty-five patients with SC were included. In 10/135 (13.5%) patients, no potential cause of IBS could be identified after complete diagnostic work-up and further clinical course. After histopathological review, a post-hoc diagnosis of EC was established in three patients resulting in a prevalence of 2.2% (3/135) of all patients with SC as well as 30% (3/10) of patients, where no cause of IBS was identified. 2/3 patients with post-hoc diagnosis of EC underwent surgical resection with suspicion for malignancy. Diagnosis of IgG4-related cholangitis was observed in 7/135 patients (5.1%), whereas 3 cases were discovered in post-hoc analysis. 6/7 cases with IgG4-related cholangitis (85.7%) presented with eosinophilic infiltration in addition to IgG4 positive plasma cells. There was no patient with eosinophilic infiltration in the control group of liver transplant donors (n= 27) and patients with primary sclerosing cholangitis (n= 14).
  
  
  CONCLUSIONS
  EC is an underdiagnosed benign etiology of SC and IBS, which has to be considered in differential diagnosis of IBS.
authors.affiliation: Dirk Walter, Stefan Zeuzem, Mireen Friedrich-Rust Department of Internal Medicine I, Johann Wolfgang Goethe-University Hospital, 60590 Frankfurt, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Walter
authors.affiliation: Dirk Walter, Stefan Zeuzem, Mireen Friedrich-Rust Department of Internal Medicine I, Johann Wolfgang Goethe-University Hospital, 60590 Frankfurt, Germany.
authors.forename: Sylvia
authors.initials: S
authors.lastname: Hartmann
authors.affiliation: Dirk Walter, Stefan Zeuzem, Mireen Friedrich-Rust Department of Internal Medicine I, Johann Wolfgang Goethe-University Hospital, 60590 Frankfurt, Germany.
authors.forename: Eva
authors.initials: E
authors.lastname: Herrmann
authors.affiliation: Dirk Walter, Stefan Zeuzem, Mireen Friedrich-Rust Department of Internal Medicine I, Johann Wolfgang Goethe-University Hospital, 60590 Frankfurt, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Peveling-Oberhag
authors.affiliation: Dirk Walter, Stefan Zeuzem, Mireen Friedrich-Rust Department of Internal Medicine I, Johann Wolfgang Goethe-University Hospital, 60590 Frankfurt, Germany.
authors.forename: Wolf O
authors.initials: WO
authors.lastname: Bechstein
authors.affiliation: Dirk Walter, Stefan Zeuzem, Mireen Friedrich-Rust Department of Internal Medicine I, Johann Wolfgang Goethe-University Hospital, 60590 Frankfurt, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Zeuzem
authors.affiliation: Dirk Walter, Stefan Zeuzem, Mireen Friedrich-Rust Department of Internal Medicine I, Johann Wolfgang Goethe-University Hospital, 60590 Frankfurt, Germany.
authors.forename: Martin-Leo
authors.initials: ML
authors.lastname: Hansmann
authors.affiliation: Dirk Walter, Stefan Zeuzem, Mireen Friedrich-Rust Department of Internal Medicine I, Johann Wolfgang Goethe-University Hospital, 60590 Frankfurt, Germany.
authors.forename: Mireen
authors.initials: M
authors.lastname: Friedrich-Rust
authors.affiliation: Dirk Walter, Stefan Zeuzem, Mireen Friedrich-Rust Department of Internal Medicine I, Johann Wolfgang Goethe-University Hospital, 60590 Frankfurt, Germany.
authors.forename: Jörg G
authors.initials: JG
authors.lastname: Albert
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D015209:Cholangitis, Sclerosing / Q000150:complications / Q000175:diagnosis* / Q000453:epidemiology / Q000473:pathology; D002779:Cholestasis / Q000175:diagnosis* / Q000209:etiology / Q000473:pathology; D003251:Constriction, Pathologic / Q000175:diagnosis* / Q000209:etiology / Q000473:pathology; D003937:Diagnosis, Differential; D004802:Eosinophilia / Q000150:complications / Q000175:diagnosis* / Q000453:epidemiology / Q000473:pathology; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D010950:Plasma Cells / Q000378:metabolism*; D015995:Prevalence; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D007074:Immunoglobulin G
keywords: IgG4-related disease; Indeterminate biliary stricture; bile duct stenosis; endoscopic retrograde cholangiopancreatography; endoscopy; eosinophilic cholangitis; primary sclerosing cholangitis