Journal of Tropical Pediatrics Advance Access published online on May 1, 2008
Journal of Tropical Pediatrics, doi:10.1093/tropej/fmn030
Linear Growth, Growth-Hormone Secretion and IGF-I Generation in Children with Neglected Hypothyroidism Before and After Thyroxine Replacement
aDepartments of Pediatrics
bClinical Pathology
cRadiology, University of Alexandria Children's Hospital, El Chatby, Alexandria, Egypt
Correspondence: Ashraf T. Soliman, Consultant Pediatric Endocrinologist, Department of Pediatrics, Hamad Medical Center, P. O. Box 3050, Doha, Qatar. Tel: 00974-5983874; Fax: 00974-4439571. E-mail < ATSOLIMAN{at}yahoo.com>.
| Abstract |
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We studied growth hormone (GH) stimulation and insulin-like growth factor -I (IGF-I) generation tests in 15 children with neglected congenital hypothyroidism (CH) (age = 6.4 ± 4.2 years) and measured their growth parameters for >1 years after starting thyroxine (T4) replacement. One year after treatment, height SDS (HtSDS) increased from –4.3 ± 2.5 to –2.7 ± 2.3. Peak GH response to clonidine increased from 3.2 ± 1.2 ng ml–1 to 7.62 ± 1.38 ng ml–1 after treatments. Basal and peak IGF-I response to GH increased from (34.66 ± 17.3 ng ml–1 and 58.4 ± 36.99 ng ml–1, respectively) before treatment to (130.6 ± 97.8 ng ml–1 and 193.75 ± 122.5 ng ml–1, respectively). HtSDS increments were correlated significantly with basal free T4 concentrations (r = 0.622, P < 0.01). In summary, after long period of hypothyroidism, T4 replacement produced significant, although incomplete, catch-up growth through a partial recovery of GH- IGF-I axis.