The IGFBP-3 Stimulation Test: A New Tool for the Diagnosis of Growth Hormone Deficiency in Children.

Overview

This project is designed to answer the question: Is there an acute IGFBP-3 response in normal children? Our specific hypothesis states that under the influence of growth hormone secretagogues, intact IGFBP-3 molecule will undergo proteolysis and liberate IGFBP-3 fragments, along with other components of the ternary complex. This proteolysis will result in measurable rise in IGFBP-3, which will indicate the subject's growth hormone status. Short children with growth hormone deficiency will not show an IGFBP-3 response.

The diagnosis of growth hormone deficiency is problematic, given the shortcoming of the standard growth hormone stimulation test. This study is designed to investigate a new tool for the diagnosis of growth hormone deficiency. Ten short, prepubertal children, who fulfill the inclusion criteria, will undergo a two-secretagogue standard growth hormone stimulation test, and an insulin like growth factor binding protein-3 (IGFBP-3) stimulation test simultaneously. During this test, components of the ternary complex moieties, viz, insulin-like growth factor-I (IGF-I), IGFBP-3 and acid labile subunit (ALS) will also be measured along with growth hormone. The aim of this study is to detect an acute rise in IGFBP-3 of \>15% from baseline. The importance of this study is that it inculcates the specificity and improved sensitivity of stimulated IGFBP-3 in the diagnosis of growth hormone deficiency.

Conditions

Interventions