Trypsin-like Immunoreactivity Levels In Your Dog And Cat = cTLI and fTLI

Ron Hines DVM PhD

See What Normal Blood & Urine Values Are

Causes Of Most Abnormal Blood & Urine Tests

See How Tests Are Grouped

Canine or Feline Trypsin-like Immunoreactivity In Your Pet’s Blood

Just like the fPL and the cPL patented tests offered by Idexx laboratories, the TLI tests offered by Antech laboratories are designed to detect abnormal leakage of digestive enzymes from your dog or cat’s pancreas into its blood stream during pancreatic inflammation (acute pancreatitis in dogs or in cats) – or the lack of the enzymes trypsin and its predecessor (trypsinogen) when the pancreas has failed in chronic pancreatitis. 

What Symptoms Might I See?

In dogs and cats, elevated results in any of these three tests are commonly associated with acute (sudden) pancreatic gland problems (acute pancreatitis). Lowered than normal digestive enzyme levels to pets with longer term pancreatic problems can result in exocrine pancreatic insufficiency aka EPI. (read about that in dog here or in cat here) Your dog or cat requires those pancreas-produced enzymes to properly digest and absorb the proteins, fats and carbohydrates in its diet. The lack of those enzymes can result in weight loss, diarrhea, abnormal stool consistency, scruffy hair coat, scooting, anal sac impaction, a lack of energy, flatulence, and a tendency to eat their or other pet’s stool (coprophagia) – even if your dog or cat’s appetite remains normal or even increases.

Reasons Your Dog Or Cat’s TLI Levels Could Be Low:

Chronic inflammation and subsequent scarring of the portion of your dog or cat’s pancreas that produces digestive enzymes (EPI). The portion of the pancreas that should be producing these enzymes is the exocrine portion. The other portions of your pet’s pancreas, the islets, are responsible for producing insulin and glucagon

Cats with inflammatory bowel disease (IBD) can have this problem as part of this complex health issue. Dogs with IBD are less likely to have their TLI levels affected. You can read about IBD in dogs here.

Cats with triad disease/cholangiohepatitis often have pancreatic problems as part of their disease syndrome. So, their TLI tests can also be below (or above) normal – depending on what stage of the disease they are in. 

Trauma or pancreatic tumors are much less likely, but possible, causes of abnormal test results. (read here)

Some dogs develop antibodies that are directed against their own pancreas (PAA, an autoimmune disease). Those pets may lose their ability to produce pancreatic trypsin. (read here)

Occasionally, TLI levels will be abnormally low (or high) in cats ill due to non-pancreatic issues. I cannot tell you why, other than that many diseases that caused generalized inflammation affect the entire body. 

Complementary Tests:

Serum amylase and lipase,   fPL test for cats or cPL test for dogs, repeat the pet’s TLI in one month. Abdominal ultrasound, blood cobalamin level and folate level, pancreatic biopsy

A normal TLI does not entirely rule out pancreatic problems in your pet


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