Sustained Eosinophilic Cholangitis Due to a Mite Allergy Mimicking Sclerosing Cholangitis

Eosinophilic cholangiopathy (EC) presents with thickening and stenosis of the bile duct wall that is his-tologically characterized by eosinophil infiltration. The diagnosis is often difficult. We herein report a patient who had been followed up with a diagnosis of primary sclerosing cholangitis but had a final diagnosis of EC based on eosinophilia, histological findings of bile duct and liver biopsy specimens, and a review of a previ-ous surgical specimen of the gallbladder. Antigen tests, isolation from her house, and accidental re-exposure to the antigen revealed that the causative antigen was the mite Dermatophagoides pteronyssinus.