IgG4 related sclerosing cholangitis.

Introduction IgG4 related sclerosing cholangitis is a novel disease entitywhich, while often associated with autoimmune pancreatitis, can presentin isolation. We describe two patients diagnosed with IgG4 related sclerosingcholangitis with contrasting clinical presentations and treatmentcourse.Case 1: A 43 year-old man was referred in Dec 2010 with painlessobstructive jaundice. He reported a 9-month history of 20 kg loss ofweight, right upper quadrant pain, fevers and deranged liver function tests.The patient had left sided proptosis, bilateral submandibular and parotidgland enlargement. An abdominal CT demonstrated mass lesions of thekidneys, liver, pancreas and gall bladder. MRCP confirmed a common bileduct stricture measuring 15 mm in length. The serum IgG4 level wasmarkedly elevated at 17.6 g/L (normal range: 0.04-0.86 g/L). The patienthad a laparoscopic cholecystectomy for the purpose of histopathologicaldiagnosis. This demonstrated multiple pseudo tumours of the gall bladder,which stained 80% positive for IgG4. Treatment with oral corticosteroidresulted in clinical and radiological remission of the patient's pseudotumours, lymphadenopathy and biliary stricture. Disease remission hasbeen maintained with azathioprine for 6 months.Case 2: A 73 year-old man presented with a 4-month history of painlessobstructive jaundice and 12 kg loss of weight. CT cholangiogram demonstrateda 2 cm hilar mass associated with a CBD stricture suspicious fora cholangiocarcinoma of the porta hepatis. Cytology on EUS guided FNAshowed benign cells. The biliary stricture and presumed cholangiocarcinomawere treated by right hemi-hepatectomy and the bile duct reconstructedwith roux-en-y limb. Histopathology of the resected lesionshowed a 20 mm x 12 x 20 mm mass with a moderate infiltration oflympho-plasmacytic cells. IgG4 immunostain of the specimen showed thatthe majority of plasma cells were IgG4 positive. The patient has not beentreated with corticosteroids as there has been no evidence