What Is Exocrine Pancreatic Insufficiency (EPI)?
Exocrine pancreatic insufficiency (EPI) is a rare disorder characterized by insufficient secretion of digestive enzymes by the pancreas. This deficiency leads to poor digestion in the small intestine, resulting in various gastrointestinal symptoms. Common clinical signs include weight loss despite increased appetite, loose or diarrheal stools, and poor coat quality.
This condition affects dogs more frequently than cats, especially German Shepherds. Both males and females can be affected. In dogs, EPI is typically diagnosed in young adults, whereas in cats, it may appear at any age.
Causes of EPI
In dogs, the main cause is atrophy of pancreatic acinar cells, structures responsible for producing digestive enzymes. In cats, the condition usually arises from chronic pancreatitis, often asymptomatic, leading to progressive destruction of acinar cells. Because the pancreas also produces insulin, chronic pancreatitis can increase the risk of developing diabetes mellitus.
Clinical symptoms become apparent when over 90% of exocrine pancreas function is lost. Most affected pets also have concurrent gastrointestinal disorders, including small intestinal bacterial overgrowth and inflammatory bowel diseases.
Diagnosing Exocrine Pancreatic Insufficiency
If a veterinarian suspects EPI, the gold-standard test is serum trypsin-like immunoreactivity (TLI). A significantly reduced serum TLI confirms the diagnosis. Measuring serum cobalamin (vitamin B12) is also recommended, as B12 deficiency is common in pets with EPI.
Additional tests to evaluate associated conditions include:
- Stool analysis to detect intestinal parasites
- Blood tests to rule out systemic causes of diarrhea and diagnose diabetes mellitus or hyperthyroidism
- Biochemical tests to assess the overall condition of the pancreas and other digestive organs
Treatment and Management of EPI
Treatment involves supplementing oral pancreatic enzymes at every meal. Dietary management is also essential:
- Highly digestible foods, low in fat and fiber
- Temporary antibiotic therapy to manage bacterial overgrowth
- Fat-soluble vitamin supplements (A, D, E, K) based on individual patient needs
- Vitamin B12 supplementation if deficiency is present
- Medium-chain triglycerides (MCT) added to food to promote weight gain
Prognosis and Follow-Up
Most animals respond positively to treatment, demonstrated by weight gain and improved stool consistency. However, EPI requires lifelong management, involving ongoing costs. Some pets are more challenging to stabilize, especially with concurrent small intestinal bacterial overgrowth or inflammatory bowel disease.
Pets suffering from both EPI and diabetes mellitus have a more guarded prognosis due to extensive pancreatic damage. Regular veterinary monitoring is critical for adjusting treatment and ensuring optimal quality of life.
