Efficacy of Growth Hormone Treatment in Patients with Noonan syndrome and Growth Hormone Deficiency

Purpose: Noonan syndrome (NS) is characterized by short stature, congenital heart defects, mild mental retardation, and characteristic faces. We investigated the efficacy of growth hormone (GH) treatment and the adverse effect compared to sex and age-matched patients with growth hormone deficiency (GHD). Methods: We included patients whose Noonan scores were over 60, treated with GH in Severance Children's Hospital. We analyzed height and height velocity before and during GH treatment in 14 NS patients (0.81 ± 0.13 U/kg/wk) and also in 42 patients with sex- and age-matched GHD as a control group (0.78 ± 0.17 U/kg/wk) at intervals of 3 months. Results: At the start of GH treatment, mean age was 10.0 ± 2.4 years, and mean height was 123.3 ± 13.5 cm, and the height SDS was -2.79 ± 0.85 in NS, while the mean age was 10.3 ± 2.6 years, mean height was 119.6 ± 13.5 cm, and the height SDS was -3.43 ± 1.56 in GHD. Mean duration was 3.8 ± 2.1 years in NS and 4.9 ± 2.4 years in GHD. Mean height SDS increased from -2.79 SDS to -1.94 SDS in NS (P = 0.007) and from -3.43 SDS to -1.82 SDS in GHD (P ˂ 0.0001). Growth velocity increased from 3.7 ± 1.2 cm/yr to 8.5 ± 2.5 cm/yr (P ˂ 0.0001) and 6.5 ± 2.9 cm/yr (P = 0.016) during the first and second years of GH treatment, respectively, in NS and from 3.4 ± 1.5 cm/yr to 8.8 ± 2.3 cm/yr (P ˂ 0.0001) and 8.1 ± 3.2 cm/yr (P ˂ 0.0001) in GHD. No severe adverse effects were observed during treatment. Conclusion: GH treatment in the NS patients increased growth velocity significantly, especially during the 1 st year of treatment. GH treatment in NS is thought to be effective and relatively safe. (J Korean Soc Pediatr Endocrinol 2011;16:100-105)