Suzuki Sawako, Ruike Yutarou, Ishiwata Kazuki, Naito Kumiko, Igarashi Katsushi, Ishida Akiko, Fujimoto Masanori, Koide Hisashi, Horiguchi Kentaro, Tatsuno Ichiro, Yokote Koutaro
Department of Endocrinology, Hematology and Gerontology, Chiba University Graduate School of Medicine, 260-8670, Japan.
Department of Neurological Surgery, Chiba University Hospital, 260-8670, Japan.
J Endocr Soc. 2022 Jun 6;6(8):bvac088. doi: 10.1210/jendso/bvac088. eCollection 2022 Aug 1.
Growth hormone deficiency (GHD) develops early in patients with hypothalamic-pituitary disorder and is frequently accompanied by other anterior pituitary hormone deficiencies, including secondary adrenal insufficiency (AI). A growth hormone-releasing peptide-2 (GHRP2) test, which is widely used for the diagnosis of patients with GHD, is thought to induce release of not only growth hormone (GH) but also ACTH. However, its clinical usefulness in hypothalamic-pituitary disorder is unclear.
We aimed to determine the clinical utility of the GHRP2 test in patients with hypothalamic-pituitary disorders, particularly for AI concomitant with GHD.
The GHRP2 test, a cosyntropin stimulation test, corticotropin-releasing hormone (CRH) tests, and/or insulin tolerance tests (ITTs) were performed on 36 patients with hypothalamic-pituitary disorder.
Twenty-two (61%) had severe GHD, and 3 (8%) had moderate GHD by GHRP2. There was no difference in baseline ACTH and cortisol between non-GHD, moderate GHD, and severe GHD participants. However, a cosyntropin stimulation test and subsequent CRH tests and/or ITTs revealed that 17 (47%) had secondary AI and 16/17 (94%) cases of secondary AI were concomitant with severe GHD. ROC curve analysis demonstrated that the ACTH response in the GHRP2 test was useful for screening pituitary-AI, with a cutoff value of 1.55-fold (83% sensitivity and 88% specificity). Notably, the combination of ACTH response and the peak cortisol level in the GHRP2 test using each cutoff value (1.55-fold and 10 µg/dL, respectively) showed high specificity (100%) with high accuracy (0.94) for diagnosis of pituitary-AI.
We recommend measuring ACTH as well as GH during the GHRP2 test to avoid overlooking or delaying diagnosis of secondary AI that frequently accompanies GHD.
生长激素缺乏症（GHD）在患有下丘脑 - 垂体疾病的患者中早期发生，并且经常伴有其他垂体前叶激素缺乏，包括继发性肾上腺皮质功能减退（AI）。一种广泛用于诊断GHD患者的生长激素释放肽 - 2（GHRP2）试验，被认为不仅能诱导生长激素（GH）释放，还能诱导促肾上腺皮质激素（ACTH）释放。然而，其在下丘脑 - 垂体疾病中的临床实用性尚不清楚。
我们旨在确定GHRP2试验在患有下丘脑 - 垂体疾病的患者中的临床效用，特别是对于与GHD并存的AI。
对36例下丘脑 - 垂体疾病患者进行了GHRP2试验、促肾上腺皮质激素（ACTH）刺激试验、促肾上腺皮质激素释放激素（CRH）试验和/或胰岛素耐量试验（ITT）。
通过GHRP2试验，22例（61%）患有严重GHD，3例（8%）患有中度GHD。非GHD、中度GHD和严重GHD参与者之间的基线ACTH和皮质醇水平无差异。然而，促肾上腺皮质激素刺激试验以及随后的CRH试验和/或ITT显示，17例（47%）患有继发性AI，16/17例（94%）继发性AI病例与严重GHD并存。受试者工作特征（ROC）曲线分析表明，GHRP2试验中的ACTH反应可用于筛查垂体性AI，临界值为1.55倍（敏感性83%，特异性88%）。值得注意的是，在GHRP2试验中使用各自的临界值（分别为1.55倍和10μg/dL）将ACTH反应和皮质醇峰值水平相结合，对垂体性AI的诊断显示出高特异性（100%）和高精度（0.94）。
我们建议在GHRP2试验期间同时测量ACTH和GH，以避免忽视或延迟对经常伴随GHD的继发性AI的诊断。
