Kline Gregory A, Boyd Jessica, Polzin Brenda, Harvey Adrian, Pasieka Janice L, Sadrzadeh Hossein S M, Leung Alexander A
Cumming School of Medicine, Department of Medicine, University of Calgary, Calgary, Canada.
Department of Clinical Pathology and Laboratory Medicine, University of Calgary, Calgary, Canada.
J Clin Endocrinol Metab. 2021 Jul 13;106(8):e2900-e2906. doi: 10.1210/clinem/dgab241.
False-positive results are common for pheochromocytoma/paraganglioma (PPGL) real-world screening.
Determine the correlation between screening urine and seated plasma metanephrines in outpatients where PPGL was absent, compared to meticulously prepared and supine-collected plasma metanephrines with age-adjusted references.
Retrospective cohort study.
Databases from a single-provider provincial laboratory (2012-2018), a validated PPGL registry, and a manual chart review from a specialized endocrine testing unit.
PPGL registry data excluded known PPGL cases from the laboratory database. Outpatients having both urine and plasma metanephrines <90 days apart.
The correlation between urine and seated plasma measures along with the total positivity rate. All cases of plasma metanephrines drawn in the endocrine unit were reviewed for test indication and test positivity rate.
There were 810 non-PPGL pairs of urine and plasma metanephrines in the laboratory database; 46.1% of urine metanephrines were reported high. Of seated outpatient plasma metanephrines drawn a median of 5.9 days later, 19.2% were also high (r = 0.33 and 0.50 for normetanephrine and metanephrine, respectively). In contrast, the meticulously prepared and supine collected patients (n = 139, 51% prior high urine metanephrines) had <3% rate of abnormal high results in patients without known PPGL/adrenal mass.
There was a poor-to-moderate correlation between urine and seated plasma metanephrines. Up to 20% of those with high urine measures also had high seated plasma metanephrines in the absence of PPGL. Properly prepared and collected supine plasma metanephrines had a false-positive rate of <3% in the absence of known PPGL/adrenal mass.
在嗜铬细胞瘤/副神经节瘤（PPGL）的实际筛查中，假阳性结果很常见。
在无PPGL的门诊患者中，将筛查尿和坐位血浆甲氧基肾上腺素的结果与精心准备且仰卧位采集的血浆甲氧基肾上腺素结果及年龄校正参考值进行比较，以确定二者之间的相关性。
回顾性队列研究。
来自单一供应商省级实验室（2012 - 2018年）的数据库、经过验证的PPGL登记册以及专门内分泌检测单位的手工病历审查。
PPGL登记数据排除了实验室数据库中已知的PPGL病例。门诊患者尿和血浆甲氧基肾上腺素检测间隔时间均小于90天。
尿和坐位血浆检测结果之间的相关性以及总阳性率。对在内分泌科采集的所有血浆甲氧基肾上腺素病例进行检测指征和检测阳性率审查。
实验室数据库中有810对非PPGL的尿和血浆甲氧基肾上腺素检测结果；46.1%的尿甲氧基肾上腺素报告为升高。在中位时间5.9天后采集的坐位门诊患者血浆甲氧基肾上腺素中，19.2%也升高（去甲氧基肾上腺素和甲氧基肾上腺素的r分别为0.33和0.50）。相比之下，精心准备且仰卧位采集样本的患者（n = 139，51%之前尿甲氧基肾上腺素升高）在无已知PPGL/肾上腺肿物的患者中异常高结果发生率<3%。
尿和坐位血浆甲氧基肾上腺素之间的相关性较差至中等。在无PPGL的情况下，高达20%尿检测结果升高的患者其坐位血浆甲氧基肾上腺素也升高。在无已知PPGL/肾上腺肿物的情况下，正确准备和采集的仰卧位血浆甲氧基肾上腺素假阳性率<3%。
