MRCEM Notes

Bile-acid malabsorption

Bile-acid malabsorption is a cause of chronic diarrhoea. This may be primary, due to an excessive production of bile acid, or secondary to an underlying gastrointestinal disorder causing reduced bile acid absorption. Secondary causes are often seen in patients with ileal disease, such as with Crohn's.

Other secondary causes include:
  • cholecystectomy
  • coeliac disease
  • small intestinal bacterial overgrowth

Investigation
  • the test of choice is SeHCAT
  • nuclear medicine test using a gamma-emitting selenium molecule in selenium homocholic acid taurine or tauroselcholic acid (SeHCAT)
  • scans are done 7 days apart to assess the retention/loss of radiolabelled 75SeHCAT

Management
  • bile acid sequestrants e.g. cholestyramine
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