PERSISTANTLY NORMAL SERUM ALKALINE PHOSPHATASE IN ENDOSCOPICALLY PROVEN PRIMARY SCLEROSING CHOLANGITIS

Primary Sclerosing Cholangitis (PSC) is a progressive cholestatic disease affecting the liver and bile ducts. Complications include cholestasis, biliary stricturing, cholangitis, cholangiocarcinoma, and colon cancer. It is strongly associated with Ulcerative Colitis (UC) with up to 90% of patients with PSC having UC (1). The diagnosis is usually made through ERCP with or without liver biopsy, but now MRCP is a developing alternative to ERCP. An elevated alkaline phosphatase is typically found in laboratory testing of PSC patients. The alkaline phosphatase and bilirubin often can fluctuate to high levels due to transient blockage of the ducts. Aminotransferases are typically less that 300IU/L (2). Hypergammaglobulinemia, increased serum IgM, p-ANCA antibodies and Human leukocyte antigen DRw52ahave also been associated with PSC (3). We present two patients that both have UC and ERCP proven PSC who have persistently normal alkaline phosphatase for approximately two years. Over time, their liver function tests have been followed and they have never had an abnormal alkaline phosphatase. Our two patients consist of a 52 year-old male and a 37 year-old female with original symptoms of abdominal pain, transient elevations in aminotrans- ferases and an abnormal ultrasound that prompted futher biliary work-up finally resulting in an ERCP. They both had known Ulcerative Colitis. Liver function tests have been followed since the diagnosis was made. Upon review of the literature, it is rare to find cases of PSC in the abscence of an elevated alkaline phosphatase. These cases show that this typical pattern of cholestasis seen in liver function tests does not always exist in PSC. We feel this is worthwhile to present to demonstrate the need to consider PSC in the differential diagnosis even in the setting of a normal alkaline phosphatase. References 1–3 available upon request