Unité Mixte de Recherche S693, Faculté de Médecine Paris-Sud, Université Paris-Sud 11, Institut National de la Santé et de la Recherce Médicale Unité 693, Service d'Endocrinologie et des Maladies de la Reproduction, Hôpital de Bicêtre, Assistance Publique-Hôpitaux de Paris, 78 Rue du Général Leclerc, Le Kremlin-Bicêtre 94275, France.
J Clin Endocrinol Metab. 2010 Aug;95(8):3684-92. doi: 10.1210/jc.2010-0295. Epub 2010 May 19.
The GHRH plus arginine (GHRH+Arg) test is a promising alternative to the insulin tolerance test (ITT) for diagnosis of adult GH deficiency (AGHD).
The objectives of the study were to validate the GHRH+Arg test for diagnosis of AGHD, using the ITT as comparator and a GH assay calibrated according to recent international recommendations, and to study the repeatability and tolerance of both tests.
This was a multicenter, randomized, open-label, phase III study.
The study was conducted at 10 French university hospitals.
Sixty-nine subjects (38 and 15 with high and low probability of GH deficiency, respectively, and 16 healthy controls) were randomized: 35 to the GHRH+Arg-GHRH+Arg-ITT test sequence and 34 to the ITT-ITT-GHRH+Arg test sequence.
Each subject underwent three tests of GH secretion separated by 24 h or more.
The primary variable used for response assessments was serum peak GH response. Test results were compared with the final AGHD diagnosis.
Peak GH responses in the two tests were strongly correlated. A cutoff value of 7.89 microg/liter for GHRH+Arg corresponding to 3 microg/liter for ITT was calculated. The cutoff value leading to 95% specificity with the GHRH+Arg test was measured at about 3.67 microg/liter (sensitivity 79.0%). Intermethod agreement and repeatability were high. Both tests were well tolerated. A preference for the GHRH+Arg test was expressed by 74% of subjects.
The GHRH+Arg test demonstrated good accuracy and repeatability, was at least as sensitive as the ITT, and was associated with better subject acceptability. The GHRH+Arg test represents a good alternative to the ITT for the diagnosis of AGHD.
生长激素释放激素（GHRH）加精氨酸（GHRH+Arg）试验是诊断成人生长激素缺乏症（AGHD）的一种有前途的胰岛素耐量试验（ITT）替代方法。
本研究的目的是使用 ITT 作为对照，并使用根据最近国际建议校准的 GH 测定法，验证 GHRH+Arg 试验诊断 AGHD 的准确性，并研究两种试验的可重复性和耐受性。
这是一项多中心、随机、开放标签、III 期研究。
该研究在法国 10 所大学医院进行。
69 名受试者（38 名和 15 名分别具有高和低 GH 缺乏可能性，以及 16 名健康对照者）被随机分组：35 名受试者接受 GHRH+Arg-GHRH+Arg-ITT 试验序列，34 名受试者接受 ITT-ITT-GHRH+Arg 试验序列。
每位受试者接受三种 GH 分泌试验，间隔 24 小时或更长时间。
用于反应评估的主要变量是血清峰值 GH 反应。将试验结果与最终的 AGHD 诊断进行比较。
两种试验的峰值 GH 反应强烈相关。GHRH+Arg 的 7.89 mcg/L 截断值对应于 ITT 的 3 mcg/L。使用 GHRH+Arg 试验测量的 95%特异性的截断值约为 3.67 mcg/L（灵敏度为 79.0%）。两种方法的一致性和重复性均较高。两种试验均具有良好的耐受性。74%的受试者表示更喜欢 GHRH+Arg 试验。
GHRH+Arg 试验具有良好的准确性和重复性，至少与 ITT 一样敏感，并且与更好的受试者可接受性相关。GHRH+Arg 试验是诊断 AGHD 的 ITT 的良好替代方法。
