Eosinophilic Cholangiopathy (EOC): An Extremely Rare Mimicker of Cholangiocarcinoma

Abstract

Purpose: EOC is one of the least recognized entities in the growing concept of eosinophilic gastrointestinal disorders and only case reports have been so far published. Its diagnosis remains difficult as it shares many clinical and radiological aspects of primary sclerosing cholangitis and biliary tract cancer. This report illustrates the first case seen in Michigan that we know about. Patient: A 65 year-old male presented with epigastric discomfort, vomiting, a 10-lb weight loss, and right upper quadrant pain radiating to the back. He was icteric and had tenderness in the upper abdomen with a negative Murphy's. The total bilirubin was 10.5, Alk Phos 376, ALT 314, with normal amylase and lipase. WBC count was normal with eosinophilia of 26.50%. CT scan of the abdomen and MRCP revealed intrahepatic biliary ductal dilation and concentric thickening of the proximal aspect of the CBD. ERCP revealed dilatation of the intrahepatic ducts. The CBD was narrow with no choledocholithiasis. CBD brushings were negative for malignant cells. Other tests included a CEA of 5.2, while alpha-fetoprotein, CA 19-9, and serum IgG4 were normal. With the presumptive diagnosis of cholangiocarcinoma, the patient underwent a CBD resection with cholecystectomy, right hepatectomy, and Roux-en-Y hepaticojejunostomy with retroperitoneal lymph node dissection. Histology demonstrated severe cholangitis and cholecystitis, with an extensive inflammatory infiltrate composed almost entirely of eosinophilis forming scattered abscesses in the gallbladder, cystic duct, right hepatic duct, common hepatic duct, and common bile duct. The patient is maintained on prednisone and has remained asymptomatic and with normal LFTs for over four months. Recent EGD and colonoscopy with biopsies were normal. Discussion: EOC is a form of secondary sclerosing cholangitis where there is diffuse infiltration of the biliary tract with eosinophils. Review of the literature reveals about 30 cases. Many were reported as eosinophilic cholecystitis, with limited case reports of concomitant cholangitis or isolated cholangitis. Eosinophilic cholangitis has also been associated with PSC, hypereosinophilic syndrome, eosinophilic gastritis and urerteritis, IgG4-related cholangitis, and hydatid disease. This condition can exist with or without peripheral eosinophilia. Prednisone has been used effectively, as well as Hydroxyurea and Ursodeoxycholic acid in steroid refractory cases. Surgery has been successful in previously unrecognized cases. Conclusion: EOC remains a difficult diagnosis to make. As our ability to diagnose EOC improves, patients may avert unnecessary surgery and may obtain prompt and effective medical therapy.