Serum level of IGF-I and IGFBP-3 and incidence of chromosomal abnormality in children with short stature

초록

Background Serum levels of insulin-like growth factor-I (IGF-I) and insulin-like growth factor binding protein-3 (IGFBP-3) are widely used as a screening test for growth evaluation. Serum levels of IGF-I, IGFBP-3, and thyroid-stimulating hormone (TSH) and chromosomal abnormality were evaluated on children with short stature. Methods: Two hundred and four children (39 males and 165 females, 1.1 to 16 years old), who presented short stature or other complaints such as precocious puberty or premature thelarche, were grouped into seven tiered groups (1–3 percentile, 97 children; 3–5 percentile, 16; 5–10 percentile 6; 10–25 percentile, 10; 25–50 percentile, 17; 50–75 percentile, 23; 75–100 percentile, 35) on the basis of the growth chart-2007 reported by the Korean Society of Pediatrics and evaluated for the serum IGF-I levels tested with the IRMA kit (Immunotech, France). Eighty-four out of 97 children who were below the 3-percentile were studied by conventional cytogenetic analysis with the G-banding technique and serum TSH levels were measured to rule out hypothyroidism. The serum IGFBP-3 levels were tested with the IRMA kit in 31 children, who were below the 3-percentile. Results The serum IGF-I level was lower than the reference value in 30.8% (63/204 tested). It was decreased in 42.3% of children below the 3-percentile (41/97), in 43.7% of children below the 10-percentile (52/119), and in 44.2% of children below the 25-percentile (57/129). However, the serum IGF-I level was lower only in 8.0% of children in the 25–100 percentile groups (6/75). Chromosomal abnormalities were found in 3.6% (3/84 evaluated cases), which were 45,X, mos 45,X[17]/46,X,+mar[13], and mos 45,X[24]/46,X,+mar[6]. TSH was increased in 7.1% (6/84 cases) and in one child with Turner mosaicism. The serum IGFBP-3 level was lower than the reference level in only one child out of 31 children below the 3-percentile. Conclusions The seru