Abstract：
PURPOSE: The diagnostic value of adding a Corticotropin-Releasing Hormone (CRH) Stimulation Test to the 2-day Low Dose Dexamethasone Suppression Test (Dex-CRH Test) has been debated in the literature.
We identified 65 patients with Cushing disease (CD) and 42 patients in whom a diagnosis of Cushing disease could not be confirmed (NCD) after a minimum follow-up of 14 months who underwent the Dex-CRH test.
The female sex ratio, median (range) age, and BMI were similar between the two groups. The follow-up for patients with CD and NCD was 74 (4-233) and 52 (14-146) months, respectively. Among 65 patients with CD, 5 (7.7%) had a cortisol level ≤1.4 µg/dl after LDDST but were appropriately classified as CD with a cortisol level >1.4 µg/dL at 15-min post CRH stimulation. In contrast, 3/42 patients (7.1%) in NCD had an abnormal Dex-CRH test. In only one of three patients, the LDDST was marginally normal (cortisol was 1.4 µg/dL and increased to 3.1 µg/dL 15-min post CRH). A cortisol cutoff value of >1.4 µg/dL during the Dex-CRH test provided a sensitivity of 100%, specificity of 93%, and diagnostic accuracy of 97% to diagnose CD. When patients without a Dex level were excluded (n = 74), the sensitivity did not change, but the specificity and accuracy of the Dex-CRH test increased to 97 and 99%, respectively.
The Dex-CRH Test provided additional case detection in 5/65 (7.7%) patients with CD. It resulted in one false-positive case compared to LDDST. Measurement of dexamethasone improved diagnostic accuracy of the test.
We identified 65 patients with Cushing disease (CD) and 42 patients in whom a diagnosis of Cushing disease could not be confirmed (NCD) after a minimum follow-up of 14 months who underwent the Dex-CRH test.
The female sex ratio, median (range) age, and BMI were similar between the two groups. The follow-up for patients with CD and NCD was 74 (4-233) and 52 (14-146) months, respectively. Among 65 patients with CD, 5 (7.7%) had a cortisol level ≤1.4 µg/dl after LDDST but were appropriately classified as CD with a cortisol level >1.4 µg/dL at 15-min post CRH stimulation. In contrast, 3/42 patients (7.1%) in NCD had an abnormal Dex-CRH test. In only one of three patients, the LDDST was marginally normal (cortisol was 1.4 µg/dL and increased to 3.1 µg/dL 15-min post CRH). A cortisol cutoff value of >1.4 µg/dL during the Dex-CRH test provided a sensitivity of 100%, specificity of 93%, and diagnostic accuracy of 97% to diagnose CD. When patients without a Dex level were excluded (n = 74), the sensitivity did not change, but the specificity and accuracy of the Dex-CRH test increased to 97 and 99%, respectively.
The Dex-CRH Test provided additional case detection in 5/65 (7.7%) patients with CD. It resulted in one false-positive case compared to LDDST. Measurement of dexamethasone improved diagnostic accuracy of the test.
摘要：
未经证实：目的：在2天低剂量地塞米松抑制试验（Dex-CRH试验）中添加促肾上腺皮质激素释放激素（CRH）刺激试验的诊断价值在文献中一直存在争议。
方法：我们确定了65例库欣病（CD）患者和42例库欣病（NCD）患者，经过最少14个月的随访，并进行了Dex-CRH测试。
结果：女性性别比例，中位（范围）年龄，两组的BMI相似。CD和NCD患者的随访时间为74（4-233）和52（14-146）个月，分别。在65例CD患者中，5（7.7％）在LDDST后皮质醇水平≤1.4µg/dl，但在CRH刺激后15分钟被适当分类为CD，皮质醇水平>1.4µg/dL。相比之下,3/42例(7.1%)NCD患者的Dex-CRH检测异常。只有三个病人中的一个，LDDST基本正常(皮质醇为1.4µg/dL,CRH后15分钟增加至3.1µg/dL).在Dex-CRH测试中，皮质醇临界值>1.4µg/dL提供了100％的灵敏度，特异性为93%，诊断CD的准确率为97%。当没有Dex水平的患者被排除在外（n=74），灵敏度没有改变,但是Dex-CRH测试的特异性和准确性提高到97％和99％，分别。
结论：Dex-CRH测试在5/65（7.7％）的CD患者中提供了额外的病例检测。与LDDST相比，它导致了一个假阳性病例。地塞米松的测量提高了测试的诊断准确性。
方法：我们确定了65例库欣病（CD）患者和42例库欣病（NCD）患者，经过最少14个月的随访，并进行了Dex-CRH测试。
结果：女性性别比例，中位（范围）年龄，两组的BMI相似。CD和NCD患者的随访时间为74（4-233）和52（14-146）个月，分别。在65例CD患者中，5（7.7％）在LDDST后皮质醇水平≤1.4µg/dl，但在CRH刺激后15分钟被适当分类为CD，皮质醇水平>1.4µg/dL。相比之下,3/42例(7.1%)NCD患者的Dex-CRH检测异常。只有三个病人中的一个，LDDST基本正常(皮质醇为1.4µg/dL,CRH后15分钟增加至3.1µg/dL).在Dex-CRH测试中，皮质醇临界值>1.4µg/dL提供了100％的灵敏度，特异性为93%，诊断CD的准确率为97%。当没有Dex水平的患者被排除在外（n=74），灵敏度没有改变,但是Dex-CRH测试的特异性和准确性提高到97％和99％，分别。
结论：Dex-CRH测试在5/65（7.7％）的CD患者中提供了额外的病例检测。与LDDST相比，它导致了一个假阳性病例。地塞米松的测量提高了测试的诊断准确性。
