title: Reduced insulin growth factor I concentrations in iron-overloaded beta thalassaemic patients with normal growth hormone secretion and liver function.
abstract: We selected 92 subjects (46 females and 46 males), aged 10-15 years, from the Haematology and Endocrine Clinic of Shiraz University, Iran. Forty-six were beta thalassaemia patients (beta-Th) with short stature, 23 had idiopathic short stature (ISS) and 23 were healthy children with a standing height between the 10th and 95th percentile. Growth hormone (GH) secretion was normal in 23 beta-Th patients and reduced in the remaining 23 patients. A low insulin growth factor I (IGF-I) was found in 73.9% of beta-Th patients with GH deficiency, 56.5% of beta-Th patients with normal GH secretion to stimulation test and 8.7% of children with ISS. The reduced IGF-I concentration in beta-Th patients with normal GH secretion may be explained by partial insensitivity to GH (GHIS), neurosecretory dysfunction, low bioactive GH or increased proportion of circulating, non-22-kDa GH isoform. The possibility of GHIS in beta-Th patients with short stature indicates that higher doses of rechGH may be required to obtain an improvement in growth velocity in beta-Th patients.
authors.affiliation: Endocrine Department, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran. karimim@sums.ac.ir
authors.forename: Hamdollah
authors.initials: H
authors.lastname: Karamifar
authors.forename: Mehran
authors.initials: M
authors.lastname: Karimi
authors.forename: Gholamhossein
authors.initials: G
authors.lastname: Amirhakimi
authors.forename: Mohammadreza
authors.initials: M
authors.lastname: Sharbatialaei
authors.forename: Vincenzo
authors.initials: V
authors.lastname: De Sanctis
mesh_terms: D000293:Adolescent; D000410:Alanine Transaminase / Q000097:blood; D001827:Body Height; D002648:Child; D002675:Child, Preschool; D003676:Deferoxamine / Q000494:pharmacology; D005260:Female; D005293:Ferritins / Q000097:blood; D019382:Human Growth Hormone / Q000378:metabolism*; D006801:Humans; D007223:Infant; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D019190:Iron Overload / Q000201:enzymology / Q000378:metabolism*; D008099:Liver / Q000201:enzymology / Q000378:metabolism; D008297:Male; D017086:beta-Thalassemia / Q000097:blood / Q000201:enzymology / Q000378:metabolism*
chemical_list: D019382:Human Growth Hormone; D007334:Insulin-Like Growth Factor I; D005293:Ferritins; D000410:Alanine Transaminase; D003676:Deferoxamine