The role of routine assays of serum amylase and lipase for the diagnosis of acute abdominal pain

Abstract

Introduction: We aimed to evaluate the role of routine measurements of serum amylase and lipase in the diagnosis of acute abdominal pain.

Patients and methods: We identified all patients who had serum amylase and lipase assays over a 62-day period at a single university teaching hospital and reviewed their case notes.

Results: We excluded 58 of the 1598 patients on grounds of ineligibility (< 18 years of age and those transferred from other hospitals). A complete data set was obtained for 1520 (98.7%) of the remaining 1540 patients. Only 9.1% of requests were based on a clinical suspicion of acute pancreatitis. Of the 44 (2.9%) patients who had acute pancreatitis, only 28 (63.6%) had an associated rise in serum amylase and/or lipase 3 times above the maximum reference range, the remainder being diagnosed radiologically. At this cut-off range, the sensitivity and specificity for serum amylase were 50% and 99%, and those for serum lipase 64% and 97%, respectively.

Conclusions: Routine measurements of serum amylase and lipase are unhelpful in the diagnosis of acute abdominal pain unless there is clinical suspicion of acute pancreatitis. In these patients, assay of lipase alone is preferable to assay of amylase alone or both enzymes.

Figure 1

Correlation between serum lipase and amylase (r² = 0.74).