Affects: Cats, Dogs
Exocrine pancreatic insufficiency (EPI) is the inability to properly digest food due to a lack or reduction of digestive enzymes made by the pancreas. EPI can occur in humans and is prevalent in many conditions such as cystic fibrosis, Shwachman–Diamond syndrome, different types of pancreatitis, multiple types of diabetes mellitus (Type 1 and Type 2 diabetes), advanced renal disease, older adults, celiac disease, diarrhea-predominant irritable bowel syndrome (IBS-D), inflammatory bowel disease (IBD), HIV, alcohol-related liver disease, Sjogren syndrome, tobacco use, and use of somatostatin analogues.
EPI is caused by a progressive loss of the pancreatic cells that make digestive enzymes. Loss of digestive enzymes leads to maldigestion and malabsorption of nutrients from normal digestive processes. EPI can cause symptoms even before reaching the stages of malnutrition: 'mild' or 'moderate' EPI is when fecal elastase levels are <[dose — ask your vet]/g, whereas 'severe' EPI is considered to be when fecal elastase levels is <[dose — ask your vet]/g.
The exocrine pancreas is a portion of this organ that contains clusters of ducts (acini) producing bicarbonate anion, a mild alkali, as well as an array of digestive enzymes that together empty by way of the interlobular and main pancreatic ducts into the duodenum (upper small intestine). The hormones cholecystokinin and secretin secreted by the stomach and duodenum in response to distension and the presence of food in turn stimulate the production of digestive enzymes by the exocrine pancreas. The alkalization of the duodenum neutralizes the acidic chyme produced by the stomach that is passing into it; the digestive enzymes serve to catalyze the breakdown of complex foodstuffs into smaller molecules for absorption and integration into metabolic pathways. The enzymes include proteases (trypsinogen and chymotrypsinogen), hydrolytic enzymes that cleave lipids (the lipases phospholipase A2 and lysophospholipase, and cholesterol esterase), and amylase to di
Signs And Symptoms: Loss of pancreatic enzymes leads to maldigestion and malabsorption. Symptoms may include:
Abdominal discomfort or pain
Abnormal stool frequency (increase)
Ataxia (vitamin E deficiency)
Bloating
Causes: In humans, the most common causes of EPI are likely related to diabetes (10.5% global prevalence of diabetes, with EPI rates of ranging from 30–50% in Type 1 and 20–30% of Type 2) and IBS-D (7.6–10.8% global prevalence of IBS-D, with EPI rates around 5–6%). Other causes of EPI include acute or chronic pancreatitis and cystic fibrosis, Crohn's disease, ulcerative colitis, celiac, advanced renal disease, older age, IBD, HIV, alcohol-related liver disease, Sjogren's syndrome, tobacco use, and use of somatostatin analogues.
EPI can also occur in 10–20% of the general population.
Causes And Pathogenesis: Pancreatic acinar atrophy and chronic pancreatitis are the most common causes of exocrine pancreatic insufficiency in dogs and cats.
In dogs, EPI is most common in young German Shepherds, and in Finland Rough Collies, and is inherited. In German Shepherds, the method of inheritance is through an autosomal recessive gene. In these two breeds, at least, the cause appears to be immune-mediated as a sequela to lymphocytic pancreatitis. The German Shepherd makes up about two-thirds of cases seen with EPI. Other breeds reported to be predisposed to EPI include terrier breeds, Cavalier King Charles Spaniels, Chow Chows, and Picardy Shepherds.
Diagnosis: The three main tests used in considering a diagnosis of EPI are: fecal elastase test, fecal fat test, and a direct pancreatic function test. The latter is a less used test that assesses exocrine function in the pancreas by inserting a tube into the small intestine to collect pancreatic secretions.
The fecal elastase test is a less cumbersome test that has replaced the 72-hour fecal fat test; in the fecal elastase test, pancreatic enzyme replacement therapy (enzyme supplementation, the treatment for EPI) does not have to be stopped for or during fecal elastase testing.
Diagnosis And Treatment: The most reliable test for EPI in dogs and cats is serum trypsin-like immunoreactivity (TLI); a low value indicates EPI. Fecal elastase levels may also be used for diagnosis in dogs.
Treatment: EPI is treated with pancreatic enzyme replacement therapy (PERT) called pancrelipase, which is used to break down fats (via a lipase), proteins (via a protease), and carbohydrates (via amylase) into units that can be digested. Pancrelipase is typically porcine derived in the prescription products although over-the-counter options also exist, including those made with plants and other non-porcine materials. In the US, there are 6 FDA-approved PERT products available on the market as of 2012.
Dosing can vary based on the individual's needs. PERT is considered to be safe, effective, and tolerable for people with EPI regardless of the cause of EPI.
In addition, various nutrient deficiencies that can be caused by EPI need to be evaluated, tested, and treated. The impact of nutrient deficiencies on the body's metabolic pathways, muscle tissue, bone density, organs, and overall health can cause a wide range of often misdiagnosed symptoms for those impacted by exocrine pancreatic insufficiency.
Since type 3c diabetes develops very frequently with chronic pancreatitis, screening tests should be done regularly. In the case of previously diagnosed diabetes, reevaluation can inform treatment.