Serum lipase levels in nonpancreatic abdominal pain versus acute pancreatitis.

OBJECTIVE

1. To determine whether serum lipase is elevated in patients with nonpancreatic abdominal pain, and 2) to compare the levels of serum lipase and serum amylase found in patients with nonpancreatic abdominal pain with those found in acute pancreatitis in order to differentiate between the two groups.

METHODS

Serum lipase and amylase levels were estimated in 95 patients with nonpancreatic abdominal pain (group A). These levels were then compared with those found in 75 patients with acute pancreatitis (group P).

RESULTS

Serum amylase in group A ranged from 11 to 416 U/L [mean 58 +/- 46 (SD)]. Three patients (3.3%) had raised amylase levels. The maximum elevation noted in this group was 416 U/L. Serum amylase in group P ranged from 124 to 13,000 U/L (mean 1620 +/- 1976). Twenty of the 75 patients (27%) in group P had levels that overlapped those found in group A. The serum lipase in group A ranged from 3 to 680 U/L (mean 111 +/- 101). Ten of the 93 patients (11%) had elevated lipase levels. The maximum elevation noted was roughly 3 times normal (680 U/L). Serum lipase in group P ranged from 711 to 31,153 (mean 6705 +/- 7022). None of the patients in group P had levels that overlapped those found in group A. The sensitivity of a serum lipase level > 3 normal in detecting acute pancreatitis was 100% and the specificity was 99%. The corresponding figures for serum amylase were 72% and 99%, respectively.

CONCLUSION

A serum lipase level > 3 normal has a better diagnostic accuracy than serum amylase in differentiating nonpancreatic abdominal pain from acute pancreatitis.