Growth in children with chronic renal faliure and after transplantation

ABSTRACT

This study aimed at studying the relation between height, glomerular filtration rate [GFR] and hormonal alteration in children with chronic renal failure [CRF] on regular hemodialysis [HD] and the possible role of normal graft function, after kidney transplantation, in this respect. The study population comprised 18 children with CRF on HD with mean age of 10.56 +/- 3.08 years and 16 children with normal graft function [mean age 11.06 +/- 3.19]. Mean duration on HD was 14.72 +/- 7.73 months for CRF group. Mean interval after transplantation was 1.97 +/- 0.9 years for the group of functioning grafts. Ten normal healthy children of matched age and sex served as controls. All patients were subjected to assessment of growth parameters including height, expressed as standard deviation scores [HtSDS] for chronological age, measurement of serum growth hormone [hGH] and serum parathormone [PTH] by radioimmunoassay. Growth performance was evaluated twice at the start of the study and after a period of one year. The overall growth retardation in children with CRF on HD corresponded to -3.16 +/- 0.43 [mean SDS for height]. Children with normal graft function had a mean HtSDS of -2.54 +/- 0.29. Growth retardation remained a critical complication after kidney transplantation despite the statistically significant improvement observed compared to the group of children with CRF [P< 0.001]. Our results confirmed that impaired HtSDS with children with CRF correlates with the duration on hemodialysis [r = -0.728, P< 0.001]. There was a significant correlation between GFR and PTH level [r = -0.750, P< 0.001] in children with CRF. Our series of children with CRF had a positive correlation between their SDS for height and GFR [r =0.760 with P<0.001]. Both categories with CRF and with normal graft function had significantly higher levels of both serum hGH and PTH compared to controls [P<0.001], while CRF children had significantly higher serum levels of both hGH and PTH compared to those with normal graft function [P<0.008 and P<0.001 respectively]. Our results support the possibility that growth retardation in children with CRF despite the normal or elevated hGH level may be explained by the presence of peripheral insensitivity to the action of hGH