Turnaround times
The quoted turnaround time is from sample receipt in the laboratory, to results authorisation in the Laboratory Information Management system. The times do not include transport of specimen to the laboratory or the administrative process to print and post/email reports. Service users must allow for transport and reporting time when ordering tests.
Clinical background:
Faecal elastase is a pancreatic-specific enzyme that is useful in the investigation of exocrine pancreatic insufficiency. Pancreatic elastase-1 remains unaffected and un-degraded during intestinal passage such that its concentration in faeces reflects the amount of enzyme secreted from the pancreas. A recent meta-analysis of studies comparing the diagnostic performance of faecal elastase measurement compared to the secretin stimulation test as a reference, determined a pooled diagnostic sensitivity of 77 % and specificity of 88 %, while compared to faecal fat as a reference, sensitivity was 96 % and specificity 88 % (Vanga et al. Clin Gastroenterol Hepatol 2018;16:1220). Faecal elastase has been recommended by the British Society of Gastroenterology in the investigation of patients with chronic diarrhoea and suspected fat malabsorption (Guidelines for the investigation of chronic diarrhoea in adults, Gut 2018;67:1380). The test is also often used to monitor patient groups at higher risk of developing pancreatic insufficiency.
Specimen container paediatric:
White universal container, random faeces
Specimen container adult:
White universal container, random faeces
Minimum volume paediatric:
5 g faeces
Minimum volume adult:
5 g faeces
Special requirements:
Not recommended in liquid samples due to possible dilution effect.
Sample stability:
Stool samples are stable at 4°C for up to 3 days.
For long-term storage, samples can be stored at -20°C for up to 6 months.
Transport requirements:
Ambient temperature.
Quality assurance:
UK National External Quality Assurance Scheme (NEQAS) for Faecal Pancreatic Elastase
Interpretation:
Pancreatic exocrine insufficiency can be caused by chronic pancreatitis, cystic fibrosis, pancreatic tumour, cholelithiasis or diabetes mellitus.
Reference ranges:
Normal exocrine pancreatic function: greater than 200 µg/g faeces
Moderate/slight exocrine pancreatic insufficiency: 100 – 200 µg/g faeces
Severe exocrine pancreatic insufficiency: less than 100 µg/g faeces
Factors affecting result:
No interference from enzyme replacement therapy. Liquid samples may not be suitable for analysis.