By Dr. Becker
Exocrine pancreatic insufficiency (EPI), also called pancreatic insufficiency and maldigestion syndrome, is thought to be rare in cats. However, according to dvm360, new research suggests veterinarians should look more closely at EPI as a potential cause of diarrhea and chronic weight loss in kitties.
Exocrine Pancreatic Insufficiency
The pancreas has many functions. It produces not only insulin, but also various enzymes that provide for the digestion of food. Many people are aware the pancreas plays a role in insulin production and diabetes; relatively few people realize the role the pancreas can play in digestive diseases.
Pancreatic enzymes include amylase, which breaks down starches; lipase, which breaks down fats; and trypsin and chymotrypsin, which break down proteins.
The actions of these enzymes are crucial to the digestive process. They allow nutrients from the diet to be absorbed by the cells of the intestine, where they pass into the bloodstream and are transported throughout the body for use by tissues. When a cat eats, the pancreas gets a signal to release digestive enzymes, which travel into the small intestine via the pancreatic duct (“exocrine” glands secrete their products into ducts, whereas “endocrine” glands secrete their products directly into the bloodstream).
Once they reach the center of the intestine, the enzymes go to work breaking down food particles.
Exocrine pancreatic insufficiency means there is a decrease or lack of digestive enzymes being produced by the pancreas. In kitties with the disorder, proteins, starches and fats from the diet aren’t broken down sufficiently to be absorbed through the intestinal wall. This means nutrients can’t get into the bloodstream to supply nourishment to the body’s tissues. Much of the food that is eaten remains undigested in the GI tract and ultimately leaves the body in feces. If left untreated, a cat with EPI can literally starve to death despite how much food is consumed.
Causes, Symptoms and Diagnosis of EPI
Pancreatic insufficiency can have several potential causes, but the most common source in cats is chronic inflammation of the pancreas. Other causes are parasitic infestations, as well as cancer.
Signs a kitty may be dealing with EPI include weight loss; constant hunger; lots of watery, loose or semi-loose stools that may have a foul odor and contain large quantities of undigested fat; and poor coat condition. Cats with this disorder look and behave as though they are starving to death … because they are.
Occasionally, cats with EPI are also diabetic.
A test called the feline trypsin-like immunoreactivity (fTLI) assay is considered diagnostic for EPI. Prior to the availability of the fTLI, diagnosis was trickier and involved taking a symptom history and running repeated fecal digestion tests.
Results of Largest Feline EPI Study to Date
In 2010, the GI Laboratory at Texas A&M University received 775 samples from veterinarians of fTLI assay results that were consistent with a diagnosis of feline EPI.
Then in 2011, researchers from the GI Laboratory and Department of Clinical Sciences at Texas A&M conducted an EPI survey of veterinarians who submitted samples. One hundred-fifty surveys were returned. The average age of affected cats with the condition was eight years. Males represented 59 percent of the samples; females, 41 percent.
Average body condition of the kitties was poor. Of the cats for which cobalamin (vitamin B12) levels were measured, 77 percent were deficient and many had no detectable levels of B12 at all. For those that had folate concentrations tested, 47 percent showed an increase.
As for symptoms, in 91 percent of the cats, weight loss was the primary symptom. Weight loss varied from 1.4 ounces to 15 pounds, with an average of 3 pounds. Loose stools were seen in 62 percent of affected cats; poor haircoat in 50 percent; loss of appetite in 45 percent and increased appetite in 42 percent; and depression was present in 40 percent of the kitties. Almost 60 percent of the cats had coexisting diseases including inflammatory bowel disease (IBD), diabetes, pancreatitis and hepatic lipidosis.
Of the kitties with EPI, 68 percent were given pancreatic enzyme supplementation. Of those, 66 percent showed a good response, 24 percent had a partial response, and 10 percent had a poor response to the treatment.
What These Results Mean for Cat Owners and Vets
According to dvm360, the results of the survey are evidence that exocrine pancreatic insufficiency is not as uncommon in cats as previously thought. However, symptoms in cats vary noticeably from canine symptoms. In cases of feline EPI, diarrhea isn’t a consistent finding and isn’t as severe as it is in dogs dealing with the disease. Also in cats, excessive hunger is not consistently present, and in fact about half the cats in the survey showed a decrease in appetite.
Treatment with pancreatic enzyme supplementation appears to be successful in a large percentage of kitties with EPI. If there are also low cobalamin levels, subcutaneous (under the skin) supplementation for several weeks is often required to help resolve gastrointestinal symptoms.
Also, EPI can be associated with small intestinal dysbiosis (also called small intestinal bacterial overgrowth, or SIBO), especially when low B12 and high folate levels are present.
Cat owners and especially veterinarians should consider fTLI, cobalamin and folate tests for kitties with unexplained weight loss or chronic diarrhea, regardless of the pet’s age. These tests could conceivably eliminate the need for more expensive and invasive diagnostic procedures.
EPI should also be viewed as a possible concurrent condition in diabetic cats whose blood sugar levels are well controlled but who have weight loss and/or diarrhea.