Amylase

Serum Amylase

Indications for performing this test: This test is performed in suspected cases of pancreatitis. Animals presenting for vomiting, depression, cranial abdominal pain, and anorexia should be evaluated with a serum amylase test.

Alpha-amylase can be found in several tissues including the intestine, kidney, uterus, and pancreas. Amylase catalyzes the hydrolysis of starch and glycogen. The majority of normal serum amylase activity is not of pancreatic origin, and serum levels will not decrease after a pancreatectomy. Duodenal mucosa is the most likely source of normal serum activity.

Can you name all the numbered structures? Which two structures contain alpha-amylase?

Hyperamylasemia could be the result of:

Enzyme leakage from degenerating pancreatic acinar cells or obstructed ducts.

Serum activity three to four times normal levels is highly indicative of pancreatic disease.

Renal failure, gastrointestinal disease, and hepatobiliary disease may also cause elevations in serum amylase.

Corticosteroid administration may either elevate or decrease serum amylase.

Special consideration in cats: Recent studies suggest that serum amylase and lipase are very poor indicators of pancreatitis in cats. It is important not to rule out pancreatitis in a cat exhibiting compatible clinical signs based solely on the amylase and lipase concentrations in the serum. fPLI may be a much more reliable diagnostic aid in the diagnosis of feline pancreatitis.

Depression and anorexia may be the primary signs seen in a cat with pancreatitis.

***Because serum amylase may increase due to other causes besides pancreatitis, it is best to analyze amylase in conjunction with lipase activity in the diagnosis of acute pancreatitis. Normal serum amylase does not rule out pancreatitis in a clinically suspicious animal dog or cat.

For more information . . .

Williams DA, Bratt RM: Sensitivity and specificity of radioimmunoassay of serum trypsin-like immunoreactivity for the diagnosis of exocrine pancreatic insufficiency. JAVMA 192: 195-201, 1988.
Veterinary Laboratory Medicine, Duncan, Prasse, and Mahaffey page 119.
Veterinary Laboratory Medicine, Interpretation & Diagnosis. Meyer & Harvey, pages 172.