P3 amylase isoenzyme in patients with cholelithiasis.

The plasma P3 amylase isoenzyme was determined in 25 patients with proven cholelithiasis. In six patients who had a single gallstone and normal pancreas at operation, the total plasma amylase was within normal limits and the P3 amylase isoenzyme was absent. In the remaining 19 patients who had multiple gallstones, pancreatitis was found at surgery in 10. In this group of 10 patients, the total plasma amylase was above the reference range for healthy individuals in only five (50%), while the P3 amylase isoenzyme band was detected in all 10 (100%). It is concluded that P3 amylase isoenzyme is superior to the total plasma amylase in the diagnosis of pancreatitis in patients with gallstone.