Decreased levels of IGF binding protein-3 in serum from children with Perthes' disease.

The concentrations of insulin-like growth factor (IGF)-I and IGF-binding protein (IGFBP)-3 in serum obtained from 27 children with Perthes' disease and 10 age-matched control subjects were measured by radioimmunoassay (RIA). IGFBPs were also analyzed by a Western ligand blotting (WLB) method. The bone age was determined in 18 patients from hand-wrist radiographs. Serum levels of IGFBP-3 but not IGF-I were significantly lower than those in normal controls. WLB showed a decrease in the intensity of the IGFBP-3 band in 19 of the 27 patients. The bone age was delayed, 2 years or more compared with the chronological age in 7 of 18 patients, and all of them, except 1, showed decreased levels of IGFBP-3 on WLB. We conclude that there may be disturbances in availability of IGFs in some patients with Perthes' disease.