NORMAL VALUES OF FIRST-PHASE INSULIN-RESPONSE TO INTRAVENOUS GLUCOSE IN HEALTHY ITALIAN CHILDREN AND ADOLESCENTS

This study reports the first-phase insulin response (FBIR) calculated on a wide pediatric population, 138 non-obese, ICA- and GAD(65) antibo dy-negative subjects, without family history of IDDM, were tested in 2 1 Italian Pediatric Diabetic Centers, according to a standardized prot ocol, After an overnight fast, 0.5 g/kg body weight of 25% dextrose (m aximum 35 g) was infused over 2.5-3 minutes, Blood samples were taken at -10, 1, 3, 5 and 10 minutes after dextrose infusion for determinati on of insulin levels by radioimmunoassay, A significant positive relat ionship was observed between FPIR and pubertal stage groups (p=0.0043) , suggesting a progressive rise of FPIR throughout puberty, These resu lts have to be taken into consideration in evaluating early abnormalit ies of carbohydrate metabolism hi pubertal subjects, According to Tann er's stage the first percentile was 53 mu U/ml for stage I, 53.6 mu U/ ml for stages D-m and 76.6 mu U/ml for stages IV-V.