Clinical usefulness of serum phospholipase A2 determination in patients with pancreatic diseases.

A new kit for radioimmunoassay of serum phospholipase A2 (PLA2) with monoclonal antibody (S-0932, Shionogi, Osaka, Japan) was used to examine PLA2 levels in patients with various diseases. Patients with acute pancreatitis showed significantly increased serum PLA2 levels. In patients with chronic pancreatitis, significant correlations were observed between the levels of factors evaluated by the secretin test and serum PLA2 levels. In patients with pancreatic cancer, serum PLA2 levels varied with disease severity. Serum PLA2 concentrations were within the normal range in patients with other malignant tumors, diabetes mellitus, and chronic liver diseases but were increased in patients with chronic renal failure. S-Sepharose column analysis of sera showed a small peak of pro-PLA2 and a large peak of PLA2 in sera from patients with severe acute pancreatitis, but a large peak of pro-PLA2 in healthy controls and patients with other diseases. On G-100 gel filtration, high-molecular-weight PLA2 immunoreactivity was detected in sera of patients with chronic renal failure, whereas a single peak of PLA2 immunoreactivity coinciding with that of standard PLA2 was detected in sera of patients with acute pancreatitis. These results suggest that (a) measurement of serum PLA2 is clinically useful for diagnosis and monitoring of pancreatitis, (b) active PLA2 in the circulation is dominant in severe acute pancreatitis, and (c) the kidney may be the main site of PLA2 degradation or excretion.