Effect of growth hormone therapy in children with achondroplasia: growth pattern, hypothalamic-pituitary function, and genotype.

OBJECTIVE: Although there are a few reports on GH therapy in achondroplasia, these were based on a small sample and/or short-term observation. To clarify the effectiveness of GH treatment on short stature in achondroplasia and hypochondroplasia, a long-term treatment study in a larger number of patients was performed.

METHOD: Forty-two children (16 males and 26 females, age 3-14 years) with achondroplasia were examined in this study. Initially, we evaluated hypothalamic-pituitary function and point mutation analysis as previously reported. After the evaluation, the children were treated with GH for more than 2 years; then post-treatment growth velocity and body proportion parameters were determined.

RESULTS: The 35 typical variants of our achondroplasia patients showed previously reported point mutation in the fibroblast growth factor receptor 3 gene. The annual height gain during GH therapy was significantly greater than that before therapy (3.9 +/- 1.0 cm/year before treatment vs 6.5 +/- 1.8 cm/year for the first year and 4.6 +/- 1.6 cm/year for the second year of treatment). The body disproportion had not been aggravated during the treatment period.

CONCLUSION: We conclude that GH might be beneficial in the treatment of short stature in children with achondroplasia in the first 2 years of treatment.