Objective: The aim of the work was to determine, in pubertal and prepubertal children, the mean values of limits of confidence for quantitative indices of insulin resistance and to evaluate the importance of these indices and other factors associated with the metabolic syndrome in the diagnostics and pathogenesis of insulin resistance. Methods: Five groups of children were examined - 33 healthy nonobese children at prepubertal age and 17 ones at the pubertal age, 15 children with overweight or obesity (BMI >90 percentile), 12 children with increased risk of incidence of the metabolic syndrome in family anamnesis and 14 adolescents with essential hypertension - quantitative homeostatic indices of insulin resistance HOMA IR and QUICKI were calcula-ted in all of them and, at the samé time, various metabolic and other indicators associated with insulin resistance were determined in sérum. Results: The increase of insulin resistance in obese children was accompanied, among other known metabolic symptoms of insulin resistance, also by important increase of sérum concentrations of leptin and IgG anticardiolipin and a significant decrease of sérum concentrations of aFABP, TNFoc and leptin receptors. Children with an increased risk of metabolic syndrome differed from the control group only in some metabolic indices, but the indices of insulin resistance were not significantly different. In boys with essential hypertension, there were only changes in some parameters (C-peptide, anticardiolipin IgG), HOMA IR a QUICKI were not significantly changed. Conclusion: The results confirmed the suitability of suing homeostatic indices od insulin resistance and some other factors for the early diagnostics of insulin resistance in children and adolescents.

        Key words: obesity, insulin resistance, homeostatic indices, metabolic syndrome, prepubertal children