The TLI test is highly sensitive and specific for the diagnosis of canine exocrine pancreatic insufficiency (EPI). This test measures the concentration of trypsin-like proteins in a blood sample by radioimmunoassay. These proteins diffuse into the blood stream in small amounts (0.01-0.1% of pancreatic trypsinogen).
- In normal dogs the TLI concentrations are greater than 5.5µg/L (up to 35µg/L).
- In dogs with exocrine pancreatic insufficiency TLI concentrations are less than 2.5µg/L.
- In dogs with pancreatitis TLI can be normal or increased.
- Dogs with bacterial overgrowth have a normal TLI test - unless exocrine pancreatic insufficiency is present as well.
- False negative results may occur if a dog has concurrent pancreatitis (increasing TLI) and exocrine insufficiency.
Last updated : October 2013