The Short Stature Homeobox-containing gene, SHOX, encodes a transcription factor involved in regulation of growth. SHOX haploinsufficient patients including those with Turner syndrome (TS) show growth impairment with or without mesomelic skeletal dysplasia. This study assessed the efficacy of GH in treating short stature associated with SHOX deficiency (SHOX-D). Prepubertal short patients (24 males, 28 females; 3.012.3 years) with molecularly-proven SHOX-D were randomized to either a GH-treatment (GH-Tx) group (Humatrope 0.05 mg/kg per d; n=27) or an untreated (Un-Tx) control group (n=25) for 2 years. For comparison 26 patients with TS (4.511.8 years) received GH (GH-Tx TS). Between-group comparisons of height velocity (HV) and height SDS were performed using ANCOVA. GH-Tx SHOX-D patients had significantly greater 1st and 2nd year HV than Un-Tx patients ((mean±S.E.M.) 8.7±0.3 vs 5.2±0.2 cm/y, 7.3±0.2 vs 5.4±0.2 cm/y, both P<0.001), which was similar to GH-Tx TS patients (8.9±0.4 cm/y, 7.0±0.2 cm/y). GH-Tx patients also had significantly greater 2nd year height SDS (−2.1±0.2 vs −3.0±0.2, P<0.001) than Un-Tx patients. GH treatment did not adversely affect body proportions. In addition, we assessed the relative effect of GH on adult height SDS gain in a separate cohort of patients with SHOX-D and TS, including 14 patients (12 females) with SHOX-D and 158 with TS from various databases. Height SDS gain from baseline was significant for each group (SHOX-D versus TS: 1.1±0.2 vs 1.2±0.1, both P<0.001). Although patients with SHOX-D received a lower GH dose (0.25 vs 0.31 mg/kg per wk, P=0.030) for a 0.9 years shorter duration, there was no significant difference in height SDS gain. We conclude that GH treatment in patients with SHOX-D improves longitudinal growth short-term as well as adult height similarly to patients with TS without adversely affecting body proportions.
03 - 07 May 2008
European Society of Endocrinology