Boyle James G, Davidson D Fraser, Perry Colin G, Connell John M C
Division of Cardiovascular and Medical Sciences, Western Infirmary, University of Glasgow, Glasgow G12 8TA, United Kingdom.
J Clin Endocrinol Metab. 2007 Dec;92(12):4602-8. doi: 10.1210/jc.2005-2668. Epub 2007 Jul 17.
Recent evidence suggests that plasma-free metanephrines provide a highly sensitive test in patients requiring exclusion of pheochromocytoma. The diagnostic efficacy of urinary free metanephrines, however, has not been evaluated. OBJECTIVE, DESIGN, SETTING, PATIENTS, AND OUTCOME MEASURES: We compared retrospectively the diagnostic efficacy of 24-h urinary free metanephrines with our currently available measurements of 24-h urinary vanillyl mandelic acid (VMA), urinary catecholamines, and plasma catecholamines in 159 outpatients tested in a tertiary referral center for pheochromocytoma over a 4-yr period.
The sensitivity of urinary free metanephrines was 100% [25 of 25 patients; 95% confidence interval (CI) 86-100%)] compared with the sensitivity of 84% (21 of 25; 95% CI 64-95%) for urinary catecholamines; 72% (18 of 25; 95% CI 51-88%) for urinary VMA; and 76% (16 of 21; 95% CI 53-92%) for plasma catecholamines. The specificity of urinary free metanephrines was 94% (116 of 123; 95% CI 89-98%), compared with the specificity of 99% (127 of 129; 95% CI 96-100%) for urinary catecholamines; 96% (130 of 134; 95% CI 91-98%) for urinary VMA; and 88% (66 of 75; 95% CI 78-94%) for plasma catecholamines. Receiver operating characteristic curves for all test groups were generated. Pairwise comparisons of the area under the receiver operating characteristic curve for urinary free metanephrines with that of each of the other three test groups individually were: 0.993 (95% CI 0.962-0.999) vs. 0.919 (95% CI 0.862-0.957, P = 0.032) for urine catecholamines; 0.993 (95% CI 0.962-0.999) vs. 0.846 (95% CI 0.778-0.900, P = 0.002) for urine VMA; and 0.992 (95% CI 0.945-0.998) vs. 0.852 (95% CI 0.762-0.918, P = 0.009) for plasma catecholamines. Testing with urinary free metanephrines failed to misidentify a single case of pheochromocytoma, compared with four missed cases for urinary catecholamines, seven missed cases for urinary VMA, and five missed cases for plasma catecholamines.
Urinary free metanephrines were superior to urinary VMA, urinary catecholamines, and plasma catecholamines and can provide a valuable test for diagnosis of pheochromocytoma in adults.
近期证据表明，对于需要排除嗜铬细胞瘤的患者，血浆游离甲氧基肾上腺素提供了一项高灵敏度检测。然而，尿游离甲氧基肾上腺素的诊断效能尚未得到评估。目的、设计、研究地点、患者及观察指标：我们回顾性比较了在一家三级转诊中心4年期间接受检测的159例门诊患者中，24小时尿游离甲氧基肾上腺素与我们目前可用的24小时尿香草扁桃酸（VMA）、尿儿茶酚胺及血浆儿茶酚胺检测的诊断效能。
尿游离甲氧基肾上腺素的灵敏度为100%（25例患者中的25例；95%置信区间[CI]86% - 100%），相比之下，尿儿茶酚胺的灵敏度为84%（25例中的21例；95%CI 64% - 95%）；尿VMA的灵敏度为72%（25例中的18例；95%CI 51% - 88%）；血浆儿茶酚胺的灵敏度为76%（21例中的16例；95%CI 53% - 92%）。尿游离甲氧基肾上腺素的特异性为94%（123例中的116例；95%CI 89% - 98%），相比之下，尿儿茶酚胺的特异性为99%（129例中的127例；95%CI 96% - 100%）；尿VMA的特异性为96%（134例中的130例；95%CI 91% - 98%）；血浆儿茶酚胺的特异性为88%（75例中的66例；95%CI 78% - 94%）。生成了所有检测组的受试者工作特征曲线。尿游离甲氧基肾上腺素的受试者工作特征曲线下面积与其他三个检测组各自的曲线下面积的两两比较结果分别为：与尿儿茶酚胺相比，0.993（95%CI 0.962 - 0.999）对0.919（95%CI 0.862 - 0.957，P = 0.032）；与尿VMA相比，0.993（95%CI 0.962 - 0.999）对0.846（95%CI 0.77 _ 0.900，P = 0.002）；与血浆儿茶酚胺相比，0.992（95%CI 0.945 - 0.998）对0.852（95%CI 0.762 - 0.918，P = 0.009）。与尿儿茶酚胺漏诊4例、尿VMA漏诊7例、血浆儿茶酚胺漏诊5例相比，尿游离甲氧基肾上腺素检测未漏诊一例嗜铬细胞瘤病例。
尿游离甲氧基肾上腺素优于尿VMA、尿儿茶酚胺及血浆儿茶酚胺，可为成人嗜铬细胞瘤的诊断提供一项有价值的检测。
