From the Guidelines
Pancreatic function testing should start with a fecal elastase test, as it is the most appropriate initial test and can be performed on a semi-solid or solid stool specimen, with a level <100 mg/g of stool providing good evidence of exocrine pancreatic insufficiency (EPI) 1.
Key Points to Consider
- The choice of test depends on clinical presentation, with fecal elastase being a common first-line test due to its non-invasiveness.
- Direct tests like endoscopic pancreatic function testing (ePFT) and secretin stimulation test provide more definitive results but are more invasive and specialized.
- Indirect tests include fecal elastase-1, which measures pancreatic enzyme levels in stool samples, and the 13C-mixed triglyceride breath test that evaluates fat digestion.
- Blood tests for pancreatic enzymes (amylase, lipase) are useful for diagnosing acute pancreatitis but less helpful for chronic conditions.
- Glucose tolerance tests help assess endocrine function by measuring insulin response.
Testing Indications
- Patients presenting with symptoms of maldigestion, unexplained weight loss, chronic diarrhea, or steatorrhea should undergo pancreatic function testing.
- The fecal elastase test is a reliable and convenient first-line test, with a single stool sample required for analysis.
Treatment and Management
- Early detection of pancreatic insufficiency allows for appropriate enzyme replacement therapy, typically with pancrelipase at doses of 25,000-40,000 units of lipase per meal, adjusted based on symptom response 1.
- Routine supplementation and monitoring of fat-soluble vitamin levels are also recommended, along with dietary modifications such as a low-moderate fat diet with frequent smaller meals and avoiding very-low-fat diets 1.
From the FDA Drug Label
The FDA drug label does not answer the question.
From the Research
Pancreatic Function Testing Methods
- Direct pancreatic function tests, such as the secretin-pancreozymin test and the Lundh test, are considered the best way to assess exocrine pancreatic function 2
- Indirect pancreatic function tests are a practicable alternative to direct tests for diagnosing exocrine pancreatic insufficiency and are useful for staging the disease and determining the need for pancreatic enzyme replacement therapy 2
- Measurement of fecal elastase-1 is recommended as the most suitable test for the initial assessment of pancreatic function 3
Comparison of Pancreatic Function Tests
- Serum lipase offers a higher sensitivity than serum amylase in diagnosing acute pancreatitis and has a larger diagnostic window 4
- The secretin-caerulein test remains the gold standard for assessing pancreatic function in patients with mild to moderate impairment of pancreatic function 3
- Indirect tests, such as the pancreolauryl test and the BT-PABA test, yield good sensitivity and specificity but are of limited value in patients with early exocrine dysfunction 3, 5
Clinical Usefulness of Pancreatic Function Tests
- Pancreatic function tests are most commonly used to diagnose chronic pancreatitis and can detect the disease at an earlier stage than imaging tests 6
- These tests can measure gradations of decreased secretory capacity and document exocrine or endocrine gland insufficiency 6
- The choice of test depends on the clinical scenario and the availability of testing methods 2, 3, 5