Reference ranges for two automated chemiluminescent assays for serum insulin-like growth factor I (IGF-I) and IGF-binding protein 3 (IGFBP-3).

摘要: Assays for insulin-like growth factor I (IGF-I) and IGF-binding protein 3 (IGFBP-3) have become essential tools in the diagnostic work-up of disorders somatotropic axis children adults. The aim this study was to evaluate automated IMMULITE IGF-I IGFBP-3 assays establish reference limits--central 95% intervals, median, 0.1 other centiles as clinically relevant--as a function age from 797 females 787 males, first week life through ninth decade. Pubertal were classified by sex sexual maturation (Tanner stage). levels also assayed 20 pediatric patients each with hormone deficiency (GHD) Turner syndrome (UTS), before during 12 months recombinant (rhGH) therapy, well 11 adult GHD seven acromegaly therapy. Both accurate, specific sufficiently sensitive measure serum good linearity recovery. In assay, potential interference IGFBPs eliminated blocking excess IGF-II. Circulating concentrations, their ratio IGF-I/IGFBP-3, age-dependent, showing low immediately after birth, typical pubertal peak girls boys, pronounced decline puberty, reaching plateau early adulthood. adults decreased smoothly but steadily age. Children UTS had circulating which increased normal limits under therapy rhGH. Adult showed below age-related median; untreated acromegalic mostly above 97.5th centile. conclusion, are reliable diagnosis pathologies GH/IGF follow-up therapies.