Pancreatic Insufficiency: What is the Fecal Elastase-1 Test?
Fecal Elastase – aid in diagnosing exocrine pancreatic insufficiency
Elastase is an enzyme made by special tissue in the pancreas, which is an organ in your upper abdomen that assists in digestion through excretion of these enzymes (as well as hormones). Elastase helps break down fats, proteins, and carbohydrates after you eat. It’s a key part of your digestive process. A fecal elastase-1 test measures the amount of elastase in your stool. Low levels of fecal elastase can be indicative of pancreatic exocrine insufficiency.
Pancreatic elastase concentrations above 200 mcg/g are normal and are not indicative of exocrine pancreatic insufficiency. Pancreatic elastase concentrations from 100-200 mcg/g are suggestive for moderate exocrine pancreatic insufficiency.
An alternative to the fecal elastase-1 test is immunoreactive trypsinogen (IRT) — this is a blood test that measures trypsinogen, an inactive precursor produced by the pancreas that is converted to the enzyme trypsin. Trypsin is the pancreatic enzyme that digests proteins. IRT may be elevated with pancreatitis, which may cause pancreatic insufficiency.
What exactly is pancreatic insufficiency?
When the pancreas is healthy and functioning normally, it produces several enzymes (which are a group of proteins that aide in the process of digestion). These enzymes are secreted into the small intestine, where they work together to digest food. In individuals with pancreatic exocrine insufficiency, the pancreas doesn’t make enough of these enzymes to adequately break down food into absorbable components. This can lead to serious nutritional deficiencies.
In adults, pancreatic insufficiency is often a sign of chronic pancreatitis. Pancreatitis is an inflammation of the pancreas. Chronic pancreatitis is a long-lasting condition that tends to get worse over time. It can lead to permanent damage of the pancreas. Acute pancreatitis, another form of the disease, is a short-term condition. It is usually diagnosed with blood and/or imaging tests, rather than a stool elastase test.
What causes pancreatic insufficiency?
Pancreatic insufficiency does not occur randomly on its own – it comes as a result of pancreatic damage. Pancreatitis (chronic, not acute), alcohol abuse, pancreatic cancer, type 1 diabetes, and certain genetic disorders are all potential causes. Additionally, inflammation from digestive diseases such as Crohn’s disease or celiac disease can contribute.
What are the symptoms?
The most prevalent symptom is fatty stools, which is a condition called steatorrhea. This occurs when the digestive system is unable to absorb dietary fats, and they pass through the intestinal tract alongside the waste products. The stool itself is very distinctive – usually oily, large, pale in colour, foul-smelling, and it also has a tendency to float in the toilet bowl. Additionally, individuals with steatorrhea can experience fecal incontinence (even slight leakage).
Nutritional deficiencies are also common, especially in regards to the fat-soluble vitamins A, D, E and K. Weight loss can occur as well, as a result of individuals not getting sufficient calories from the food they eat. Weight loss is far more common in those who have an additional digestive disease (like Crohn’s).
Symptoms of nutrient malabsorption and their typical causes:
- Fatigue (insufficient calories/nutritional deficiencies)
- Anemia (vitamin B-12 or iron deficiency)
- Bone diseases stemming from vitamin D deficiency
- Bleeding disorders, problems clotting, bleeding under the skin, blood in the feces or urine (caused by vitamin K deficiency)
Watch our CDHF Talk with Dr. Karen Kroeker from the University of Alberta who explains the important role stool tests play in diagnosis and treatment of digestive disorders.