生理盐水试验对原发性醛固酮增多症诊断价值的再评价

Revaluation on the clinical value of saline infusion test in diagnosis of primary hyperaldosteronism

目的评价生理盐水试验(SIT)对原发性醛固酮增多症(PA,简称原醛症)的诊断价值。方法回顾性分析2014年1月-2016年3月在解放军总医院内分泌科诊治并进行盐水输注试验的132例高血压患者的临床资料,包括PA组72例及原发性高血压(EH)组60例。根据盐水输注后血浆醛固酮的变化,绘制受试者工作曲线(ROC)并寻找诊断PA的最佳切点。结果 PA组和EH组立位醛固酮/肾素活性比值(ARR)≥20的患者分别占83.3%和15.0%,无论PA或EH组,盐水负荷前后两组间(ARR<20与ARR≥20)血浆醛固酮水平差异均无统计学意义(P>0.05)。与立位ARR≥20的患者比较,EH组立位ARR<20者肾素活性更高(P<0.01),血钠水平更低(P<0.05)。盐水负荷后,PA组和EH组患者中血浆醛固酮水平仍大于10ng/dl的比例分别为91.7%和75.0%,诊断PA的最佳切点值为388.1pmol/L(14.0ng/dl),曲线下面积(AUC)为0.674,敏感度及特异度分别为63.9%及66.7%,约登指数(YI)为0.3。结论生理盐水输注是一项安全且可靠的PA确诊方法,盐水负荷后血浆醛固酮的最佳诊断切点值取决于研究人群的纳入及诊断标准。

Objective To evaluate the diagnostic value of saline infusion test（SIT） for patients with primary hyperaldosteronism（PA）. Methods The data of 132 patients with hypertension, admitted to the Department of Endocrinology of Chinese PLA General Hospital and undergone saline infusion test from Jan. 2014 to Mar. 2016, were retrospectively analyzed. Of the 132 subjects, 72 were with primary hyperaldosteronism（PA group） and 60 were with essential hypertension（EH group）. The receiver operating characteristic（ROC） curve was drawn up based on the altered level of plasma aldosterone after infusion of saline and used to judge the suitable tangent point of PA diagnoses. Results 83.3% and 15.0% patients, respectively, in PA group and EH group were with the erect aldosterone-to-active renin ratio（ARR） ≥20. No significant difference existed in plasma aldosterone levels of patients between PA and EH group（ARR20 and ARR≥20） before and after SIT（P〈0.05）. Compared to the patients with erect ARR≥20 in EH group, those with erect ARR20 in the same group had higher renin activity（P〈0.01） and lower blood sodium level（P〈0.05）. After saline load, 91.7% and 75.0% patients, respectively, in PA group and EH group were with the plasma aldosterone levels greater than 10 ng/dl. The optimal cut-off point for PA diagnoses was 388.1 pmol/L（14.0 ng/dl）, the relevant area under the ROC curve（AUC） was 0.674, the sensitivity and specificity were 63.9% and 66.7%, respectively, and the Youden index（YI）was 0.3. Conclusions SIT is a safe and reliable method for the diagnosis of PA. The best cut-off point of plasma aldosterone after saline loading is depended on recruited population and the diagnostic criteria.