title: Normal and proton pump inhibitor-mediated gastrin levels in infants 1 to 11 months old.
abstract: BACKGROUND
  Scant data exist on the normal range of serum gastrin in infants. In phase I and III trials of rabeprazole in gastroesophageal reflux disease, we studied serum gastrin levels in infants 1 to 11 months old, and assessed normal ranges and the effect of acid-suppressive drugs.
  
  
  METHODS
  Overall, 349 treatment-naïve or treatment-experienced (previously exposed to proton pump inhibitors and/or H2-receptor antagonists) infants with gastroesophageal reflux disease were screened for baseline serum gastrin. Repeat gastrin was monitored at early termination or end of study, allowing assessment of 1 to 8 week daily rabeprazole (5- or 10-mg) treatment on gastrin levels.
  
  
  RESULTS
  Median (5%-95% range) baseline gastrin was 118 ng/L (39-315) in the treatment-naïve group (n = 251), driven mostly by high levels (121.5 [48-326] ng/L) in the 1- to <4-month-old subgroup. Treatment-experienced infants (n = 98) had elevated baseline gastrin levels (152 [48-487] ng/L; P = 0.0011) with no clear difference between previously proton pump inhibitor-exposed and H2-receptor antagonist-exposed groups. At the end of study, mean (standard deviation) levels were unchanged from baseline in infants withdrawn from rabeprazole to placebo (124 [94] ng/L), but elevated from baseline in those continuing treatment with 5-mg (245 [151] ng/L) and 10-mg (332 [222] ng/L) rabeprazole during the study.
  
  
  CONCLUSIONS
  Gastrin levels in treatment-naïve infants were elevated through 8 months of age. Between 8 and 12 months of age, they declined so that the median level was within the upper limit of the normal adult range (<100 ng/L). Previous exposure to acid-suppressive medications and short-term exposure to rabeprazole significantly increased gastrin levels in infants younger than 1 year.
authors.affiliation: Janssen Research & Development, LLC, Titusville, NJ.
authors.forename: William
authors.initials: W
authors.lastname: Treem
authors.forename: Peter
authors.initials: P
authors.lastname: Hu
authors.forename: Sheldon
authors.initials: S
authors.lastname: Sloan
mesh_terms: D005755:Gastrins / Q000097:blood*; D005764:Gastroesophageal Reflux / Q000097:blood* / Q000188:drug therapy; D006635:Histamine H2 Antagonists / Q000494:pharmacology / Q000627:therapeutic use; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D054328:Proton Pump Inhibitors / Q000494:pharmacology* / Q000627:therapeutic use; D064750:Rabeprazole / Q000494:pharmacology* / Q000627:therapeutic use; D012016:Reference Values
chemical_list: D005755:Gastrins; D006635:Histamine H2 Antagonists; D054328:Proton Pump Inhibitors; D064750:Rabeprazole