Just Ask the Expert: Which test is better-PLI or lipase activity?

Dr. Smallwood welcomes internal medicine questions from veterinarians and veterinary technicians.

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If I want to evaluate a patient for pancreatitis, is measurement of canine pancreatic lipase immunoreactivity (cPLI) or feline pancreatic lipase immunoreactivity (fPLI) necessary when total lipase activity is low or normal on a serum chemistry profile?

A. Both cPLI and fPLI tests are considered to be more sensitive screening tests for pancreatitis than is measuring amylase and lipase activity.

Dr. Laura J. Smallwood

In one study in which amylase, lipase, and pancreatic lipase activities were correlated with histologic evidence of pancreatitis in a group of dogs, amylase activity had a sensitivity of 18.2%, lipase activity had a sensitivity of 13.6%, and cPLI had a sensitivity of 63.6%.1

Lipase activity reported on the serum chemistry profile reflects total lipase, so it can be in the normal range even though the pancreatic component is elevated, which is why cPLI is a more sensitive test for pancreatitis. The negative predictive value for cPLI and fPLI is high, which means you can generally rule out pancreatitis in patients when tests results are normal, regardless of the amylase and lipase activity results. A positive result, however, doesn't guarantee that pancreatitis is the sole cause of the patient's clinical signs.

In summary, normal total serum lipase activity does not rule out pancreatitis. For this reason, I recommend performing a cPLI or fPLI test when pancreatitis is suspected. The cPLI or fPLI result should carry greater weight in patient assessment than the serum lipase results.

REFERENCE

1. Steiner JM, Newman S, Xenoulis P, et al. Sensitivity of serum markers for pancreatitis in dogs with macroscopic evidence of pancreatitis. Vet Ther 2008;9(4):263-273.

Laura J. Smallwood, DVM, DACVIM

Saint Francis Veterinary Specialists

625 Dekalb Industrial Way

Decatur, GA 30033