Exocrine Pancreatic Insufficiency

Exocrine Pancreatic Insufficiency

Exocrine Pancreatic Insufficiency (EPI) is also referred to as Pancreatic Hypoplasia or Pancreatic Acinar Atrophy (PAA)

BASICS

Exocrine pancreatic insufficiency (EPI) is the inability to properly digest food due to a lack of digestive enzymes made by the pancreas. While the disease may occur in all species, it is frequently found in dogs. In animals, symptoms of EPI may not present until 85 to 90 percent of the pancreas is unable to secrete its enzymes.

EPI is caused by a progressive loss of the pancreatic acinar cells that make digestive enzymes, which results in the inadequate production of the digestive enzymes. Most commonly in dogs, this is caused by pancreatic acinar atrophy.

The systems affected by EPI are:
• Gastrointestinal System - duodenal mucosal disease which includes villus atrophy, inflammatory cellular infiltrates, and abnormal mucosal enzyme activities. This also then leads to bacterial overgrowth.

• Endocrine System & Metabolism--dogs may be protein-calorific malnourished.

Without these naturally produced pancreatic digestive enzymes, food remains undigested and unabsorbed resulting in an EPI dog, who although is eating copious amounts of food, is constantly undernourished and can literally waste away. Without proper treatment, the EPI dog can die a painful death from malnourishment/starvation or organ failure.

With EPI, organs, the immune, nervous and all other body systems may become compromised to one degree or another. A lack of nutrients often results in temperament changes which may express themselves in fear and/or aggression.

Causes

Chronic pancreatitis is the most common cause of EPI in humans and cats, but it is an uncommon cause in dogs. Idiopathic pancreatic acinar atrophy is the most common cause of exocrine pancreatic insufficiency in dogs.

Occasionally exocrine pancreatic insufficiency develops with adenocarcinoma and pancreatic duct obstruction.

Deficient exocrine pancreatic secretion results in mal-digestion, nutrient malabsorption, and osmotic diarrhoea. Secondary complication of the malabsorption contributes to bacterial overgrowth, which may cause secretory diarrhoea.

Genetics

EPI is assumed to be hereditary and is relatively common in the German Shepherds and transmitted by an autosomal recessive trait. It may also be seen in other breeds of dogs, but is rare in cats. It is currently thought to be multiple loci, possibly a polygenic inheritance (traits vary in degrees of severity of the disease).

Other breeds reported to be predisposed to EPI include terrier breeds, Cavalier King Charles Spaniels, Chow Chows and Picardien Shepherd.

Age and Sex Signs typically occur as a consequence of pancreatic acinar atrophy in young dogs. In older dogs Chronic pancreatitis is also a likely cause. Cats suffering from EPI tend to be middle aged to older.

There is no gender predisposition

Signs to look for:

• Weight loss accompanied by a normal to increased appetite

• Chronic watery diarrhoea of small bowel origin in many animals.

• Diarrhoea may be continuous or intermittent.

• Faecal volumes larger than normal and steatorrhea (excess fat in faeces) is present.

• Diarrhoea generally lessens in severity when a low-fat, highly digestible diet is fed.

• Flatulence and borborygmus (Bowel sounds, the gurgling, rumbling, or growling noise from the abdomen caused by the muscular contractions of peristalsis, the process that moves the contents of the stomach and intestines downward-Websters New World Medical dictionary )common

• Coprophagia (eating poo) and pica (A craving for something not normally regarded as nutritive) in some animals

• Polyuria (profuse urination) and polydipsia (Excessive thirst all the time) may be seen in animals with diabetes mellitus caused by chronic pancreatitis.

• Thinness

• Reduced muscle mass

• Poor quality hair / coat

CAUSES

• Pancreatic acinar atrophy

• Chronic relapsing pancreatitis

• Pancreatic adenocarcinoma (cancer)

• Duodenal mucosal disease

• Pancreatic fluke (Eurytrema procyonis) infection in cats

DIFFERENTIAL DIAGNOSIS

• Exocrine pancreatic insufficiency should be differentiated from all other causes of malabsorption.

• Common causes of malabsorption include small intestinal mucosal diseases which are best diagnosed by intestinal mucosal biopsy.

• Rule out chronic parasitism by performing multiple faecal examinations.

• Rule out diabetes mellitus and hyperthyroidism in cats.

Tests for EPI

DOGS

The most effective test for dogs is the Assay for Serum Trypsin-like Immunoreactivity (TLI) this is a highly reliable test for Dogs with EPI. Dogs with EPI will show a reduced TLI concentration.

CATS

The assay for TLI is not available for cats. There are 3 other tests available:

•  The bentiromide (BTPABA) absorption test - indirectly assesses pancreatic enzyme activity in the small intestine. Requires multiple samples.
• Assays of faecal proteolytic activity by use of casein-based substrates are accurate means of diagnosing exocrine pancreatic insufficiency in both dogs and cats. – Needs multiple faecal specimens and the lack of availability for clinicians.
  
• Typically, serum folate concentration is high and cobalamin (B12) concentration is low in animals with concurrent bacterial overgrowth.
  

TREATMENT
The vast majority of animals can be treated a home, however animals with oncurrent diabetes mellitus may require an initial period of hospitalization for insulin regulation.

DIET

Dietary modification is a cornerstone of treatment in dogs. Characteristics of the ideal diet include:

• highly digestible, lowfiber (<4%), and nutritionally balanced.
  
• Some Dogs will require a reduced fat intake, others will not,
  
• Supplement food with medium chain fats, easily absorbed by an EPI’ such as coconut oil.
  
• Slipper elm (herb) powder is used on a temporary basis or occasionally to help sooth irritated intestines. It's mucilage substance coats intestines allowing irritation to heal. It should not be used at the same time as other medications as it can reduce absorption of other medications. If using concurrently with other medications feed them at separate times of the day. • High digestibility reduces nutrient availability for bacterial overgrowth.
• Avoid high fat diets since fat absorption remains impaired despite appropriate administration of enzymes.
  
• Avoid high-fiber diets since fiber inhibits the activity of pancreatic enzymes.
• Addition of Pancreatic Enzymes to the diet
  
• Severely malnourished dogs may require supplementation with cobalamin, tocopherol, and fat- soluble vitamins A, D, E, and K. Pancreatic Enzyme Replacement
• Administration of pancreatic enzyme concentrates is the treatment of choice. Powdered nonenteric coated preparations are most ideal. (Avoid the use of enteric coated tablets since the dissolution of their enteric protective coating is unpredictable.)
  
  • Amylase for digestion of carbohydrates (sugars & starches in grains, fruits & vegetables),
    
  • Lipases for digestion of fats and oils, and
    
  • Trypsin and Proteases for digestion of proteins.
    

Antibiotics
Antibiotics may be required for dogs with concurrent bacterial overgrowth.

PROBIOTICS may be needed to be added to the diet either after an antibiotic regiment to replace good gut flora, or during antibiotic treatment 4 hours AFTER antibiotics are given.

COBALAMINE (B12) and folate depletion. This is normally treated with B12 injections.

EXPECTED COURSE AND PROGNOSIS

Most causes of EPI are irreversible and lifelong treatment is required. Where appropriate enzyme and dietary management plans are in place prognosis is good. Animals that suffer concurrent The prognosis in dogs with exocrine pancreatic insufficiency alone is good with appropriate diabetes mellitus caused by chronic pancreatitis, the prognosis is less sure.

References

Williams DA Exocrine pancreatic disease. In: Ettinger SJ, Feldman EC, eds . Textbook of veterinary internal medicine. 4th. ed. Philadelphia: WB Saunders, Philadelphia, 1995.

Williams DA New tests of pancreatic and small intestinal function. Compend Contin Educ Pract Vet 1987; 9:11671174.

Williams DA Sensitivity and specificity of serum trypsinlike immunoreactivity for the diagnosis of canine exocrine pancreatic insufficiency. J Am Vet Med Assoc 1988;192;195201.

Simpson JW, Maskell IE Quigg J, et al. Long term management of canine exocrine pancreatic insufficiency. J Small Anim Pract 1994; 35:133138.

Strombeck, DR, Guilford WG Small animal gastroenterology. Davis, Calif: Stonegate Publishing, 1990.