Measurement of multiple steroids, 17 hydroxyprogesterone, 11 deoxycortisol, and 21 deoxycortisol, is required to discriminate between congenital adrenal hyperplasia due to 21 hydroxylase deficiency and that due to 11 beta hydroxylase deficiency. This work aims at the selection of the more appropriate, cost-effective method among either mass spectrometry or radioimmunoassay for the quantitation of the previous steroids. In this study, blood samples were collected from 31 patients that were newly diagnosed with congenital adrenal hyperplasia; 17 hydroxyprogesterone and 21 deoxycortisol were assayed using tandem mass spectrometry. Eleven deoxycortisol was assayed using 2 methods: radioimmunoassay and tandem mass spectrometry. Measuring 11 deoxycortisol using tandem mass spectrometry could significantly discriminate patients with 11 beta hydroxylase deficiency from those with 21 hydroxylase deficiency (p = 0.002), whereas radioimmunoassay failed (p = 0.095). Moreover, the former was highly predictive of 11 beta hydroxylase deficiency at a cutoff ≥ 11 ng/ml with 100% sensitivity and 92.3% specificity. Simultaneous measurement of 21 deoxycortisol and 11 deoxycortisol and their enrollment in an equation yielded an overall predictive accuracy 96.8% for diagnosis of CAH due to both enzymatic deficiencies. Measurement of 11 deoxycortisol using mass spectrometric approach is mandated as a part of work up to differentiate types of congenital adrenal hyperplasia.

中文翻译：

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质谱法：用于区分先天性肾上腺增生的原因及其与放射免疫分析相比的益处的基本工具

需要测量多种类固醇、17 羟孕酮、11 脱氧皮质醇和 21 脱氧皮质醇，以区分 21 羟化酶缺乏引起的先天性肾上腺增生和 11 β 羟化酶缺乏引起的先天性肾上腺增生。这项工作的目的是在质谱或放射免疫分析中选择更合适、更具成本效益的方法来定量以前的类固醇。本研究采集了31名新诊断为先天性肾上腺皮质增生症患者的血液样本；使用串联质谱法测定了 17 羟孕酮和 21 脱氧皮质醇。使用两种方法测定了 11 种脱氧皮质醇：放射免疫测定法和串联质谱法。使用串联质谱法测量 11 脱氧皮质醇可以显着区分 11 β 羟化酶缺乏症患者和 21 羟化酶缺乏症患者 (p = 0.002)，而放射免疫测定失败 (p = 0.095)。此外，前者在临界值 ≥ 11 ng/ml 时高度预测 11 β 羟化酶缺乏症，具有 100% 的敏感性和 92.3% 的特异性。由于两种酶缺陷，同时测量 21 脱氧皮质醇和 11 脱氧皮质醇并将它们纳入方程得出 CAH 诊断的总体预测准确度为 96.8%。使用质谱法测量 11 脱氧皮质醇是区分先天性肾上腺增生类型的工作的一部分。前者在临界值 ≥ 11 ng/ml 时高度预测 11 β 羟化酶缺乏症，具有 100% 的敏感性和 92.3% 的特异性。由于两种酶缺陷，同时测量 21 脱氧皮质醇和 11 脱氧皮质醇并将它们纳入方程得出 CAH 诊断的总体预测准确度为 96.8%。使用质谱法测量 11 脱氧皮质醇是区分先天性肾上腺增生类型的工作的一部分。前者在临界值 ≥ 11 ng/ml 时高度预测 11 β 羟化酶缺乏症，具有 100% 的敏感性和 92.3% 的特异性。由于两种酶缺陷，同时测量 21 脱氧皮质醇和 11 脱氧皮质醇并将它们纳入方程得出 CAH 诊断的总体预测准确度为 96.8%。使用质谱法测量 11 脱氧皮质醇是区分先天性肾上腺增生类型的工作的一部分。