Activity of phospholipase A compared in serum of patients with pancreatic and nonpancreatic diseases.

Phospholipase A (PLA) activity was measured with a semi-automated photometric test system that is based on liberation of fatty acids from phosphatidylcholine by phospholipases A1 (EC 3.1.1.32) and A2 (EC 3.1.1.4). We studied 528 serum samples from 86 patients whose lipase activities were increased owing to pancreatitis, pancreatic carcinoma, and extrapancreatic diseases. PLA activity showed no correlation with lipase or amylase activities or with the primary cause of the disease, but was clearly related to prognosis. Noncomplicated acute pancreatitis was characterized by "normal" PLA activities (0-10 U/L), whereas the values (50-137 U/L) were highest in necrotizing pancreatitis and septicemia with a lethal outcome. Changes in lipase and phospholipase A activities exhibited completely different time courses in the various diagnostic groups.