The use of insulin-like growth factor 1 reference values for the diagnosis of growth hormone deficiency in prepubertal children

Clin Endocrinol (Oxf). 2000 Jun;52(6):735-9. doi: 10.1046/j.1365-2265.2000.00999.x.


Objective: This study was done to determine whether the use of reference values obtained in children with idiopathic short stature (ISS) improved the clinical value of serum insulin-like growth factor I (IGF-1) as a tool for diagnosing GH deficiency (GHD) in prepubertal children.

Patients and methods: Serum IGF-1 was measured with a new IRMA kit (IGFI-RIA CT, Cis Bio, Gif sur Yvette, France) in 168 prepubertal normal children and in prepubertal children with ISS (n = 68), organic GHD due to a craniopharyngioma (oGHD, n = 15) and permanent idiopathic GHD (iGHD, n = 28).

Results: IGF-1 was lower (P < 0.001) in iGHD than in either ISS or oGHD and was below the fifth percentile of the normal range in 29/68 ISS (43%), 8/15 oGHD (53%) and 28/28 (100%) iGHD patients. Three oGHD (20%) and two iGHD (7%) patients had a serum IGF-1 below the fifth percentile of the normal group but above the fifth percentile of the ISS group. Thus, a serum IGF-1 below the fifth percentile of the normal group distinguished between normal children and iGHD with 100% sensitivity, between normal and oGHD with 53% sensitivity and between normal and all GHD (idiopathic + organic) with 84% sensitivity; the overall specificity was only 57%. Conversely, a serum IGF-1 below the fifth percentile of the ISS population distinguished between ISS and iGHD with 93% sensitivity, between ISS and oGHD with 33% sensitivity and between ISS and all GHD with 72% sensitivity; the overall specificity was then 95%.

Conclusions: A serum IGF-1 within the normal range virtually excludes idiopathic GHD but does not rule out organic GHD, whereas an IGF-1 below the ISS range is strongly in favour of GHD, after exclusion of poor nutritional status and/or liver disease. An IGF-1 below the normal range but in the idiopathic short stature range gives no definitive conclusion even when it is associated with a low GH peak. Thus, whereas reference values obtained in normal children must be used to interpret serum IGF-1 in short prepubertal children, reference data obtained in idiopathic short stature children should also be taken into account.

MeSH terms

  • Child
  • Child, Preschool
  • Craniopharyngioma / blood*
  • Craniopharyngioma / complications
  • Female
  • Growth Disorders / blood*
  • Growth Disorders / etiology
  • Growth Hormone / blood
  • Growth Hormone / deficiency*
  • Humans
  • Infant
  • Insulin-Like Growth Factor I / analysis*
  • Male
  • Pituitary Neoplasms / blood*
  • Pituitary Neoplasms / complications
  • Predictive Value of Tests
  • Reference Values
  • Sensitivity and Specificity


  • Insulin-Like Growth Factor I
  • Growth Hormone