Symptomatic sclerosing cholangitis in patients with a normal alkaline phosphatase: two case reports and a review of the literature.

The diagnosis of sclerosing cholangitis is usually not considered in the absence of an elevation of serum alkaline phosphatase. The purpose of this paper is to report two symptomatic cases of primary sclerosing cholangitis (PSC) which presented with a normal alkaline phosphatase, and to review the literature regarding alkaline phosphatase in PSC. A total of 172 patients with PSC were identified in the literature; six of these patients (3%) presented with a normal alkaline phosphatase. Patients with diseases known to be associated with primary sclerosing cholangitis and having a compatible clinical presentation should be considered for evaluation with endoscopic retrograde cholangiography, even in the presence of a normal level of serum alkaline phosphatase.