SKELETAL IMMATURITY, IGF-I AND IGFBP-3 SERUM CONCENTRATIONS IN LEGG-CALVE-PERTHES DISEASE (SKELETAL IMMATURITY, IGF-I AND IGFBP-3 IN LCPD)

Background Skeletal immaturity is a major feature in Lepp-Calve-Perthe s disease (LCPD). Evaluation of growth hormone concentration, somatome din activity, or insulin-like growth factor I (IGF-I) concentration re vealed inconsistent results. Recently, IGF-binding protein 3 (IGFBP-3) was found normal in relation to chronological age in LCPD patients. P atients In this study IGF-I and IGFBP-3 were measured in the serum of 23 children with unilateral LCPD and in 23 sex and age matched control s. Methods IGF-I and IGFBP-3 were measured with radioimmunoassays, usi ng an IGF binding site-blocked assay for IGF-I. The results were relat ed to the chronological age in all and to the bone age in 19 of the pa tients. Results Bone age was retarded in 16 of 19 patients with a dela y of one year or more in twelve children (mean 14.75, range 2-35 month s). Chronological age and bone age related IGF-I and IGFBP-3 serum con centrations were predominantly within the normal ranges and did not di ffer significantly from the matched controls. IGF-I and IGEBP-3 serum levels showed a high correlation, which was similar in LCPD (r=0.7; p < 0.0001) and in the control group (r=0.8; p < 0.0001). Conclusions Ou r data confirm that most children with LCPD are skeletally immature. H owever, IGF-I measured with IGF-II-blocked IGFBP binding sites, and IG FBP-3 serum concentrations analysed with respect to bone age show no e vidence for a disturbance of the hypothalamo-pituitary-somatomedin axi s in these children.