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It is mandatory measurement of fat-soluble vitamins in patients with cystic fibrosis?
Thank you for your question,

It is widely recognised that malabsorption of fat-soluble vitamins (A, D, E, K) is likely in the majority of individuals with cystic fibrosis, particularly those who are pancreatic insufficient. Low serum levels of vitamins A and E have also been observed in those individuals with pancreatic insufficiency. Even infants less than 3 months old have been observed to have biochemical deficiencies of vitamins A and E. Biochemical deficiencies have been shown to be associated with poorer clinical status in individuals with CF. Factors that may contribute to deficiency of fat-soluble vitamins in CF include
•Inadequate intake
•Malabsorption – possibly due to suboptimal pancreatic enzyme replacement therapy (PERT) and/or due to residual or incomplete bile salt absorption
•Poor clinical status
•Increased utilisation and reduced bio-availability
•CF related liver disease
•Bowel resection
•Late diagnosis of CF
•Poor adherence to or inappropriate supplementation regimens.

In Summary
•Serum levels of fat soluble vitamins A D and E should be measured routinely at a time of clinical stability in all CF individuals. The PIKVA II test for vitamin K measurement should be considered, although not routinely available.
•All fat soluble vitamin levels should be interpreted based on current supplementation dose, adherence to supplementation and PERT, clinical status, other serum levels (eg Zn and RBP for vitamin A interpretation), season of measurement (vitamin D) and renal (vitamin D) or liver disease (vitamins A ,D and K)
•Supplementation is recommended if vitamin levels are low.
•Monitor vitamin levels and review the supplementation regimen 3-6 monthly until levels normalise, then revert back to annual monitoring.

I hope this is a help to you,
Best wishes,
Dee Shimmin


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9. Australasian Clinical Practice Guidelines for Nutrition in Cystic Fibrosis 2005.
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The answer is edited by: Dee Shimmin