title: Diagnosis of bile acid diarrhoea by fasting and postprandial measurements of fibroblast growth factor 19.
abstract: BACKGROUND
  A deficiency in the ileal hormone fibroblast growth factor 19 (FGF19) has been described in patients with bile acid diarrhoea (BAD), but fasting FGF19 levels have insufficient diagnostic power. We assess whether single postprandial sampling of FGF19 has greater discriminative value than fasting FGF19 for detection of BAD and we evaluate the reproducibility of fasting FGF19.
  
  
  METHODS
  Twenty-six patients consecutively referred to Se homocholic acid retention test (SeHCAT) were included. Serum FGF19 was measured after an overnight fast and again 1 h postprandially and again in the fasting state 1 week later.
  
  
  RESULTS
  Nine of 26 patients had SeHCAT less than 10% and fasting FGF19 was lower [median 62 pg/ml, interquartile range (IQR): 47-67] than in the 17 diarrhoea controls with SeHCAT at least 10% (median 103 pg/ml, IQR: 77-135, P=0.006). Postprandial FGF19 in BAD patients (61 pg/ml, IQR: 48-69) was similar to fasting values (P=0.59) and increased insignificantly in diarrhoea controls (137 pg/ml, IQR: 88-182; P=0.25). The difference in postprandial FGF19 between patients with BAD and diarrhoea controls was highly significant (P<0.001).
  
  
  CONCLUSIONS
  The difference in serum FGF19 between groups of patients with BAD and diarrhoea controls is amplified postprandially. Within each group, the difference between fasting and postprandial FGF19 was not statistically significant. Further investigations are warranted on stimulated FGF19 response to elucidate its role in BAD.
authors.affiliation: Departments of aInternal Medicine bClinical Biochemistry cClinical Physiology, Køge Hospital, Køge dDepartment of Clinical Physiology, Hvidovre Hospital, Hvidovre eDepartment of Internal Medicine and Clinical Research Unit, Gentofte Hospital, Hellerup fFaculty of Health and Human Sciences, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Christian
authors.initials: C
authors.lastname: Borup
authors.forename: Charlotte
authors.initials: C
authors.lastname: Syversen
authors.forename: Pierre
authors.initials: P
authors.lastname: Bouchelouche
authors.forename: Morten
authors.initials: M
authors.lastname: Damgaard
authors.forename: Jesper
authors.initials: J
authors.lastname: Graff
authors.forename: Jüri Johannes
authors.initials: JJ
authors.lastname: Rumessen
authors.forename: Lars Kristian
authors.initials: LK
authors.lastname: Munck
mesh_terms: D000328:Adult; D000368:Aged; D001647:Bile Acids and Salts / Q000378:metabolism*; D015415:Biomarkers / Q000097:blood; D002908:Chronic Disease; D003967:Diarrhea / Q000175:diagnosis*; D005215:Fasting / Q000502:physiology; D005260:Female; D005346:Fibroblast Growth Factors / Q000097:blood*; D006801:Humans; D008297:Male; D008875:Middle Aged; D019518:Postprandial Period / Q000502:physiology; D011446:Prospective Studies; D015203:Reproducibility of Results
chemical_list: D001647:Bile Acids and Salts; D015415:Biomarkers; C117476:FGF19 protein, human; D005346:Fibroblast Growth Factors