faecal elastase (pancreatic)

Last reviewed 04/2021

• elastase is a pancreatic enzyme, which helps to break down connective tissue. It is present in the serum, urine and faces. Pancreatic elastase does not undergo any significant degradation during intestinal transit and, therefore, acts as a useful marker of pancreatic activity
• assessment of exocrine pancreatic function has traditionally been carried out using invasive, unpleasant and expensive procedures. Measurement of faecal elastase has been shown to be an excellent practical alternative to these procedures and has the advantage of being carried out on random faecal specimens
  • pancreatic elastase-1 has been isolated and characterized as a pancreas-specific protease in humans that undergoes minimal degradation during intestinal transit
    • approximately six-fold enriched in faeces compared with duodenal juice
  • faecal elastase 1 (FE1) is an indirect test which has improved the diagnostic approach
  • excellent correlation has been found between the FE1 level and duodenal juice amylase, lipase and trypsin values in both controls and chronic pancreatitis patients
    • measurement of FE1 has been shown to be an excellent indicator of pancreatic insufficiency, with a sensitivity of 90% to 100% and a specificity of 93% to 100%, even while patients are taking pancreatic enzyme supplements
    • sensitivity of FE1 in mild chronic pancreatitis is in the range 0-65%, and in moderate to severe disease is 33-100%
      • specificity of FE1 varies between 29% and 95%
      • steatorrhoea of non-pancreatic origin may artificially lower FE1 concentration, presumably due to dilutional effects from diarrhoea

Reference:

1. Chowdury RS, Forsmark CE. Pancreatic function testing. Aliment Pharmacol Ther. 2003 Mar 15;17(6):733-50.
2. Waise Ahmed (August 2007), Consultant Biochemist, York Hospital.