Objective: To evaluate growth and endocrine parameters in RTX children with GH treatment during 24 months.
Subjects: 18 children (13 boys), age 13.1 yr (8.0-16.6), bone age 10.1 yr (5.4-15.3). Patients were 2.8 yr (0.5-7.5) after RTX and had immunosuppressive therapy, prednisone 0.16 mg/kg/d (0.08-0.68).
Methods: GH (4 IU/m2/day s.c.) was given and patients were seen every 3 months for evaluation of height, height velocity, bone age, and hormone parameters. Serum IGF-I was determined by RIA, IGFBP-3 by RIA and Western ligand blotting (WLB). Renal function and adverse effects (GFR, glucose tolerance, rejection episodes) were monitored.
Results: Height (+1 SDS) and height velocity (+2.2 SDS) increased significantly during 24 months GH treatment, but delta BA/delta CA was 1.7 and 1.5 during the first and second treatment year, respectively, and all patients entered puberty during the treatment period. GFR decreased slightly during 2 yr (p = 0.048), two patients had chronic rejection and GH therapy was terminated in one patient because of glucose intolerance. The ratio IGF-I/IGFBP-3 rose during the first year (p = 0.002) indicating more bioavailable IGF-I. IGFBP-3 determined by WLB was decreased, but IGFBP-1, -2 and -4 were elevated as compared to a standard.
Conclusions: GH treatment increased height and growth rate in children after RTX. This may be due to significant changes in IGF-I and IGFBP-3 relationship. However, bone maturation was also accelerated thus diminishing height potential. From month 12 to 24 a continuous decrease of IGF-I was observed. There was a slight but significant deterioration of graft function. Adverse events that led to termination of GH therapy were observed in 3 of 18 patients.