Preliminary report of the (13)C-mixed triglyceride breath test to assess timing of pancreatic enzyme replacement therapy in children with cystic fibrosis

J Cyst Fibros. 2016 Sep;15(5):669-74. doi: 10.1016/j.jcf.2016.03.008. Epub 2016 Apr 19.


Background: Despite guidelines suggesting pancreatic enzyme replacement therapy (PERT) should be taken before or during a meal, it is currently unknown whether this has benefits over administration after a meal in individuals with cystic fibrosis (CF).

Methods: 18 children with pancreatic insufficient CF were randomised to two (13)C-mixed triglyceride ((13)C-MTG) breath tests to assess lipase activity with PERT administered 10min before and 10min after a meal. Results were expressed as percentage cumulative dose recovered (PCDR) of (13)CO2 and were compared with established values in healthy subjects. Gastric half emptying time (T½) was also assessed by a (13)C-octanoate breath test.

Results: There was no difference in mean PCDR of (13)CO2 between taking PERT before versus after the meal (p=0.68). Eleven subjects had a greater PCDR when PERT was taken before and 7 when PERT was taken after the meal. 6/8 subjects (75%) with a lower than normal PCDR at one time point normalised PCDR when PERT timing was changed. When PERT was taken after the meal, PCDR was higher in normal vs. fast T½ (p=0.04).

Conclusions: Changing PERT timing can result in normalised lipase activity. Gastric emptying rate may influence optimal timing of PERT. Clinical Trial Registration Number - This study was undertaken prior to the registration process being a commonly required practice.

Keywords: Cystic fibrosis; Gastric emptying; Lipase activity; Pancreatic enzyme replacement therapy.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adolescent
  • Breath Tests / methods
  • Child
  • Cystic Fibrosis* / diagnosis
  • Cystic Fibrosis* / metabolism
  • Cystic Fibrosis* / physiopathology
  • Cystic Fibrosis* / therapy
  • Dietary Fats / metabolism
  • Drug Administration Schedule
  • Enzyme Replacement Therapy / methods*
  • Female
  • Gastric Emptying / drug effects
  • Gastric Emptying / physiology
  • Gastrointestinal Agents / administration & dosage
  • Gastrointestinal Agents / adverse effects
  • Humans
  • Lipase / analysis*
  • Male
  • Pancreas / enzymology*
  • Pancreatic Function Tests / methods
  • Pancrelipase* / administration & dosage
  • Pancrelipase* / adverse effects
  • Time Factors
  • Triglycerides* / analysis
  • Triglycerides* / metabolism


  • Dietary Fats
  • Gastrointestinal Agents
  • Triglycerides
  • Pancrelipase
  • Lipase