title: Partial growth hormone deficiency (GHD) in children has more similarities to idiopathic short stature than to severe GHD.
abstract: BACKGROUND
  Assessment of growth hormone (GH) secretion is based on stimulation tests. Low GH peaks in stimulation tests, together with decreased insulin-like growth factor-I (IGF-I) secretion, confirm a diagnosis of GH deficiency (GHD). However, limitations in interpreting the test results and discrepancies between GH and IGF-I secretion in particular patients have both been reported. GH therapy should improve the prognosis of adult height (PAH). The aim of the study was to compare the deficit of height at diagnosis, IGF-I secretion and PAH in children with either decreased (in varying degrees of severity) or normal GH secretion in stimulation tests.
  
  
  METHODS
  The analysis comprised 540 short children (373 boys, 167 girls), aged 11.7 +/- 3.2 years. In all the patients two GH stimulation tests were performed, IGF-I serum concentration was measured, bone age was assessed and PAH was calculated. According to the GH peak in the two stimulation tests, the patients were classified into the following groups: severe GHD (sGHD)--GH peak < 5 ng/mL (n = 44), partial GHD (pGHD)--GH peak 5-10 ng/mL (n = 190), idiopathic short stature (ISS)--GH peak at least 10 ng/mL (n = 306).
  
  
  RESULTS
  A significantly greater deficit of height, lower IGF-I secretion and worse PAH were observed in sGHD than in both remaining groups, while all the differences between pGHD and ISS in the parameters analysed were insignificant.
  
  
  CONCLUSIONS
  The results obtained indicate the necessity of applying another methods of qualifying short children for GH therapy other than GH stimulation tests with a cut-off value at a level of 10 ng/mL.
authors.affiliation: Department of Endocrinology and Metabolic Diseases, Polish Mother's Memorial Hospital--Research Institute, Łódź.
authors.forename: Joanna
authors.initials: J
authors.lastname: Smyczyńska
authors.forename: Andrzej
authors.initials: A
authors.lastname: Lewiński
authors.forename: Maciej
authors.initials: M
authors.lastname: Hilczer
authors.forename: Renata
authors.initials: R
authors.lastname: Stawerska
authors.forename: Michał
authors.initials: M
authors.lastname: Karasek
mesh_terms: D000293:Adolescent; D000365:Age Determination by Skeleton; D001827:Body Height; D002648:Child; D005260:Female; D006130:Growth Disorders / Q000097:blood*; D019382:Human Growth Hormone / Q000097:blood / Q000172:deficiency*; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000032:analysis / Q000378:metabolism*; D008297:Male; D011237:Predictive Value of Tests
chemical_list: D019382:Human Growth Hormone; D007334:Insulin-Like Growth Factor I