Laboratory - Acute Pancreatitis

Serum amylase: Large elevations (>3 × normal) virtually assure the diagnosis if salivary gland disease and intestinal perforation/infarction are excluded. However, normal serum amylase does not exclude the diagnosis of acute pancreatitis, and the degree of elevation does not predict severity of pancreatitis. Amylase levels typically return to normal in 3-7 days.
Serum lipase level: Serum lipase is the preferred test for diagnosis of acute pancreatitis. Increases in parallel with amylase level and measurement of both tests increases the diagnostic yield.
Other tests: Hypocalcemia occurs in ~25% of pts. Leukocytosis (15,000-20,000/µL) occurs frequently. Hypertriglyceridemia occurs in 15-20% of cases and can cause a spuriously normal serum amylase level. Hyperglycemia is common. Serum bilirubin, alkaline phosphatase, and aspartame aminotransferase can be transiently elevated. Hypoalbuminemia and marked elevations of serum lactic dehydrogenase (LDH) are associated with an increased mortality rate. Hypoxemia is present in 25% of pts. Arterial pH <7.32 may spuriously elevate serum amylase.