Department of Endocrinology and Hypertension, Tokyo Women's Medical University, Tokyo, Japan.
Hypertens Res. 2020 Jun;43(6):543-549. doi: 10.1038/s41440-020-0406-4. Epub 2020 Feb 4.
Urinary measurement of fractionated metanephrines is one of the best available biochemical tests for the diagnosis of pheochromocytoma and paraganglioma; however, false-positive results remain an issue. In addition, despite their convenience, there is no evidence to suggest that spot urine samples should replace the standard 24-h urine collection method. The objective of this study is to elucidate clinical variables that may influence the levels of spot urine fractionated metanephrines and to examine their instability. The study is a retrospective review of prospectively collected data from 949 patients whose spot urine fractionated metanephrines were measured under suspicion of pheochromocytoma or paraganglioma at our institution from January 2011 to June 2017. The effects of clinical factors such as age, sex, renal function, and medications on the level of spot urine fractionated metanephrines were evaluated. Urinary fractionated metanephrines were significantly higher in female subjects. They correlated with age but not with estimated glomerular filtration rate (eGFR). A multivariate regression model for urinary fractionated metanephrine levels revealed that age, female sex, eGFR, and the presence of α1-blocker medication were significantly positively correlated with urinary metanephrine (M) levels. Age, female sex, eGFR, and presence of α1-blockers and antidepressant and antipsychotic medications positively correlated with urinary normetanephrine (NM). In addition, age, female sex, eGFR, and presence of α1-blockers and antidepressant and antipsychotic medications were positively correlated with urinary M + NM. In conclusion, sex, age, eGFR, and treatment with α1-blockers, antidepressants, and antipsychotics may affect the levels of urinary fractionated metanephrines. When assessing urinary fractionated metanephrines in patients with suspected PPGLs, we must consider these factors.
尿中分次测定甲氧基肾上腺素是诊断嗜铬细胞瘤和副神经节瘤的最佳生化检测之一；然而，假阳性结果仍然是一个问题。此外，尽管它们很方便，但没有证据表明点尿样应该取代标准的 24 小时尿液收集方法。本研究的目的是阐明可能影响点尿分次甲氧基肾上腺素水平的临床变量，并研究其不稳定性。该研究是对 2011 年 1 月至 2017 年 6 月期间我院因怀疑患有嗜铬细胞瘤或副神经节瘤而检测点尿分次甲氧基肾上腺素的 949 例患者前瞻性收集数据的回顾性分析。评估了年龄、性别、肾功能和药物等临床因素对点尿分次甲氧基肾上腺素水平的影响。女性患者的尿分次甲氧基肾上腺素明显升高。它们与年龄相关，但与估算肾小球滤过率（eGFR）无关。尿分次甲氧基肾上腺素水平的多变量回归模型显示，年龄、女性、eGFR 以及α1 阻滞剂的存在与尿甲氧基肾上腺素（M）水平显著正相关。年龄、女性、eGFR 以及α1 阻滞剂、抗抑郁药和抗精神病药的存在与尿去甲甲氧基肾上腺素（NM）水平呈正相关。此外，年龄、女性、eGFR 以及α1 阻滞剂、抗抑郁药和抗精神病药的存在与尿 M+NM 呈正相关。总之，性别、年龄、eGFR 以及α1 阻滞剂、抗抑郁药和抗精神病药的治疗可能会影响尿分次甲氧基肾上腺素的水平。在评估疑似 PPGLs 患者的尿分次甲氧基肾上腺素时，我们必须考虑这些因素。
