Amylase normal, lipase elevated: is it pancreatitis? A case series and review of the literature.

Abstract

This study was undertaken to identify clinical scenarios in which the lipase is significantly elevated (three times above the upper limit of normal) but the amylase is normal, and to examine whether or not pancreatitis is the likely cause for this seemingly unusual constellation of laboratory results. Twenty-five patients were retrospectively identified over a 2-yr period, which fulfilled the above criteria. A thorough review of their charts was conducted. In addition, a critical review of the literature was performed. It appears that isolated elevation of lipase in this case series was either related to renal insufficiency (two patients), to nonpancreatic sources of lipolytic enzymes due to malignant tumors (two), to acute cholecystitis (two) or esophagitis (one), to delayed blood withdrawal (at least five patients), to hypertriglyceridemia (two), or to subclinical pancreatitis in patients without abdominal pain (three). 1. An elevated lipase should not be equated with evidence for pancreatitis if the amylase is normal. 2. A simultaneous determination of both amylase and lipase is recommended for the evaluation of patients with abdominal pain.