Administration of arginine plus growth hormone releasing hormone to evaluate growth hormone (GH) secretory status in children with GH deficiency.
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.


CONCLUSIONS
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.
Keller
A
A
Hospital for Children and Adolescents, University of Leipzig, Germany. alexandra.keller@medizin.uni-leipzig.de
Donaubauer
J
J
Kratzsch
J
J
Pfaeffle
R
R
Hirsch
W
W
Kiess
W
W
Keller
E
E
D000293:Adolescent; D000367:Age Factors; D001120:Arginine / Q000008:administration & dosage* / Q000097:blood; D001786:Blood Glucose / Q000032:analysis; D001827:Body Height / Q000187:drug effects; D002648:Child; D002675:Child, Preschool; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods; D004305:Dose-Response Relationship, Drug; D005260:Female; D015200:Fluoroimmunoassay / Q000379:methods; D013007:Growth Hormone-Releasing Hormone / Q000008:administration & dosage* / Q000097:blood; D019382:Human Growth Hormone / Q000097:blood / Q000172:deficiency* / Q000378:metabolism*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D007262:Infusions, Intravenous; D007328:Insulin / Q000008:administration & dosage / Q000097:blood; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000032:analysis / Q000378:metabolism; D007334:Insulin-Like Growth Factor I / Q000032:analysis / Q000378:metabolism; D008297:Male; D010900:Pituitary Diseases / Q000097:blood / Q000175:diagnosis; D013997:Time Factors
D001786:Blood Glucose; D007328:Insulin; D018972:Insulin-Like Growth Factor Binding Protein 3; D019382:Human Growth Hormone; D007334:Insulin-Like Growth Factor I; D013007:Growth Hormone-Releasing Hormone; D001120:Arginine; D006854:Hydrocortisone