Eosinophilic cholangitis with initial clinical features indistinguishable from IgG4-related cholangitis.

A 66-year-old woman presented with jaundice, elevated liver enzymes, peripheral eosinophilia and increased levels of immunoglobulin (Ig) G4. The image findings of the biliary tree revealed multifocal strictures mimicking primary sclerosing cholangitis. A biopsy specimen of the liver demonstrated an infiltration of inflammatory cells consisting of several eosinophils and IgG4-positive plasma cells. The liver enzymes and eosinophil count were normalized immediately after the administration of an oral steroid. Finally, the patient was diagnosed with eosinophilic cholangitis based on the clinical manifestations, although she had features of both eosinophilic cholangitis and IgG4-related cholangitis. This case indicates that the two entities may show similar manifestations and thus they should be discriminated carefully.