Pediatric patients with Prader-Willi syndrome (PWS) can be treated with recombinant human GH (rhGH). These patients are highly sensitive to rhGH and the standard doses suggested by the international guidelines often result in IGF-1 above the normal range. We aimed to evaluate 1 the proper rhGH dose to optimize auxological outcomes and to avoid potential overtreatment, and 2 which patients are more sensitive to rhGH. In this multicenter real-life study, we recruited 215 patients with PWS older than 1 year, on rhGH at least for 6 months, from Italian Centers for PWS care. We collected auxological parameters, rhGH dose, IGF-1 at recruitment and (when available) at start of treatment. The rhGH dose was 4.3 (0.7/8.4) mg/m²/week. At recruitment, IGF-1 was normal in 72.1% and elevated in 27.9% of the patients. In the group of 115 patients with IGF-1 available at start of rhGH, normal pretreatment IGF-1 and uniparental disomy were associated with elevated IGF-1 during the therapy. No difference in height and growth velocity was found between patients treated with the highest and the lowest range dose. The rhGH dose prescribed in Italy seems lower than the recommended one. Normal pretreatment IGF-1 and uniparental disomy are risk factors for elevated IGF-1. The latter seems to be associated with higher sensitivity to GH. In case of these risk factors, we recommend a more accurate titration of the dose to avoid overtreatment and its potential side effects.

患有Prader-Willi综合征（PWS）的小儿患者可以用重组人GH（rhGH）治疗。这些患者对rhGH高度敏感，国际指南建议的标准剂量通常会使IGF-1超出正常范围。我们的目标是评估1适当的rhGH剂量以优化临床治疗效果并避免潜在的过度治疗，以及2哪些患者对rhGH更敏感。在这项多中心的真实生活研究中，我们从意大利的PWS护理中心招募了215名至少1个月的rhGH至少6个月的PWS患者。我们在募集时和治疗开始时（如果可用）收集了生理参数，rhGH剂量，IGF-1。rhGH剂量为4.3（0.7 / 8.4）mg / m ²/周。募集时，IGF-1正常的占72.1％，而升高的占27.9％。在115位在rhGH开始时可用的IGF-1患者中，正常的治疗前IGF-1和单亲二体性与治疗期间IGF-1升高有关。在最高和最低剂量范围内的患者之间没有发现身高和生长速度的差异。意大利规定的rhGH剂量似乎低于推荐剂量。正常的预处理IGF-1和单亲二体性是IGF-1升高的危险因素。后者似乎与对GH的更高敏感性有关。如果存在这些危险因素，我们建议更准确地确定剂量，以免过度治疗及其潜在的副作用。