Urinary growth hormone during puberty in normal and diabetic children

The measurement of GH in urine may have many clinical applications, particularly in childhood. We have used a highly sensitive direct immunoradiometric assay to examine urinary GH excretion in children during puberty. Fifty-five healthy schoolchildren collected timed overnight urine samples. A further 36 children (15 normal, six of short stature and 15 diabetic) collected urine samples during a total of 50 overnight plasma GH secretory profiles (15-min sampling). Overnight urinary GH excretion increased during puberty, with a peak at breast stage 2 in girls, and genital stage 4 in boys, before declining at stage 5. There was a positive correlation (r = 0.57, p = 0.003) with height velocity in girls, but not in boys. At each puberty stage except 2, the diabetics excreted more urinary GH than the normal children. There was a highly significant correlation (r = 0.79, p less than 0.001) between mean overnight plasma GH concentrations and urinary GH excretion, suggesting that the latter accurately reflects physiological GH secretion.