Somatomedin in children with chronic renal insufficiency - relationship to growth rate and energy intake.

The relationship of energy intake, growth rate and serum concentration of somatomedin-A was evaluated in eighteen children with chronic renal insufficiency. Serum concentrations of somatomedin-A were found to be 0.84 micro/ml in normal children and were elevated to 3.06 micro/ml in children with chronic renal insufficiency prior to dialysis (p less than 0.01). Somatomedin-A concentrations increased during chronic hemodialysis to 5.81 micro/ml and decreased to 1.59 micro/ml following successful renal transplantation (p less than 0.01). Serum concentrations of somatomedin-A correlated with residual glomerular filtration rates (r = -0.5), serum creatinine concentration (r = 0.59), and blood urea nitrogen (r = 0.6). Growth rates correlated with energy intake (r = 0.58) and somatomedin-A concentrations (r = 0.4) in the children with chronic renal insufficiency. Both energy intake and somatomedin-A increased significantly after one year of nutritional supplementation. Our findings are consistent with the hypothesis that somatomedin, like other polypeptide hormones, is elevated in uremia and that increased energy intake may affect the growth of children with chronic renal insufficiency by increasing somatomedin levels.