Administration of Arginine Plus Growth Hormone Releasing Hormone to Evaluate Growth Hormone (GH) Secretory Status in Children With GH Deficiency

J Pediatr Endocrinol Metab. 2007 Dec;20(12):1307-14. doi: 10.1515/jpem.2007.20.12.1307.

Abstract

Background: Diagnosis of growth hormone deficiency (GHD) in childhood is usually based on growth hormone (GH) response to at least two provocative stimuli. The aim of this study was to determine whether sequential administration of arginine (Arg) plus GH releasing hormone (GHRH) could be a useful tool in evaluating GHD in children.

Methods: Thirty patients with short stature (mean age 9.0 years) with decreased growth rate were tested for GHD with Arg and the insulin tolerance test (ITT). Patients with confirmed GHD (peak GH <8 ng/ml) were subsequently tested with Arg + GHRH.

Results: Maximum GH stimulation for Arg and ITT was 6.3 (1.0-7.8) and 6.7 (0.5-7.7) ng/ml, respectively. Peak GH for the Arg + GHRH test was 36.3 (4.3-84.5) ng/ml and significantly different from the other provocative tests. Peak GH values for the three tests were not significantly correlated between tests or with clinical parameters. There were no significant differences in Arg + GHRH results between children with or without abnormal hypothalamic-pituitary MRI scans.

Conclusion: Arg + GHRH gave higher GH levels than insulin or Arg alone. Because of the different causes of childhood GHD (hypothalamic and/or pituitary dysfunction), the Arg + GHRH test is unsuitable .for evaluating GHD and deciding whether GH replacement therapy is indicated.

Publication types

  • Clinical Trial

MeSH terms

  • Adolescent
  • Age Factors
  • Arginine / administration & dosage*
  • Arginine / blood
  • Blood Glucose / analysis
  • Body Height / drug effects
  • Child
  • Child, Preschool
  • Diffusion Magnetic Resonance Imaging / methods
  • Dose-Response Relationship, Drug
  • Female
  • Fluoroimmunoassay / methods
  • Growth Hormone-Releasing Hormone / administration & dosage*
  • Growth Hormone-Releasing Hormone / blood
  • Human Growth Hormone / blood
  • Human Growth Hormone / deficiency*
  • Human Growth Hormone / metabolism*
  • Humans
  • Hydrocortisone / blood
  • Infusions, Intravenous
  • Insulin / administration & dosage
  • Insulin / blood
  • Insulin-Like Growth Factor Binding Protein 3 / analysis
  • Insulin-Like Growth Factor Binding Protein 3 / metabolism
  • Insulin-Like Growth Factor I / analysis
  • Insulin-Like Growth Factor I / metabolism
  • Male
  • Pituitary Diseases / blood
  • Pituitary Diseases / diagnosis
  • Time Factors

Substances

  • Blood Glucose
  • Insulin
  • Insulin-Like Growth Factor Binding Protein 3
  • Human Growth Hormone
  • Insulin-Like Growth Factor I
  • Growth Hormone-Releasing Hormone
  • Arginine
  • Hydrocortisone