卡托普利试验在醛固酮腺瘤无创诊断中的临床价值

目的:分析原发性醛固酮增多症(primary aldosteronism,PA)中醛固酮腺瘤(aldosterone-producing adenoma,APA)亚型的临床特点及卡托普利试验(captopril challenge test,CCT)在APA诊断中的应用价值,尝试寻找从PA中识别APA的临床特异性无创指标。方法:回顾性收集因高血压住院患者的临床资料,确诊PA者90例,其中手术证实为APA者34例。对两组患者临床指标,包括CCT前后的血浆醛固酮浓度(plasma aldosterone concentration,PAC)、醛固酮/肾素比值(aldosterone to renin ratio,ARR)以及CCT后的醛固酮抑制率(%)进行比较,并绘制CCT前后相关指标的受试者工作特征曲线,比较曲线下面积(area under the curve,AUC)。结果:与PA组相比,APA患者确诊时高血压病程较短,低血钾发生率更高,血钾平均水平更低,两者的血压水平、性别分布、血钠水平、体重指数差异无统计学意义。APA组CCT前ARR及CCT后PAC、ARR、醛固酮抑制率均较PA组高,其中CCT前后ARR均对APA有诊断价值:CCT前ARR临界点为7.12时,灵敏度为35.85%,特异度为77.78%;CCT后ARR临界点为4.23时,灵敏度为71.43%,特异度为62.22%;两者对PA分型的诊断价值相当。CCT前ARR>7.12联合低血钾的诊断特异度高达80%。结论:CCT前后ARR对APA的诊断均具有临床价值,当联合低血钾时诊断特异度增高。

Clinical value of captopril test in noninvasive diagnosis of aldosterone-producing adenoma

Objective: To analyze the clinical characteristics of aldosterone-producing adenoma (APA) subtypes in primary aldosteronism (PA) and the application value of captopril challenge test (CCT) in adenomas. And to find out the clinically specific non-invasive index for identifying APA subtypes from PA. Methods: The clinical data of hospitalized patients with hypertension were retrospectively collected. All the patients were conducted with the CCT and 90 patients with PA were confirmed. Among them, 34 patients were confirmed to have APA by surgery. The clinical indicators of the two groups of patients including plasma aldosterone concentration (PAC), aldosterone inhibition rate (%), and aldosterone to renin ratio (ARR) before and after the CCT were compared, the receiver operating characteristic (ROC) curves for the relevant indicators before and after the CCT drawn, and the areas under the curve (AUC) compared. The ROC curves were used to analyze the efficiency of the different CCT diagnostic criteria for diagnosing APA. Results: Compared with the PA group, the duration of hypertension was shorter, the incidence of hypokalemia was higher, and the average serum potassium level was lower when APA was diagnosed. There were no significant differences in blood pressure level, gender, serum sodium and body mass index between the two groups. Compared with PA population, APA group had higher PAC and ARR whether before or after the CCT, but lower plasma renin concentration (PRC). In APA patients, the mean degree of PAC declined after CCT was approximately 5.7%, but 5% with that of PA. As for diagnosing, ARR before or after CCT had diagnostic value for APA, in which the ARR cut-off point was 7.12, which yielded a sensitivity and specificity of 35.85% and 77.78%. The cut-off point of ARR after CCT was 4.23, with a sensitivity of 71.43% and specificity of 62.22%. For the diagnosis, the ARR before and after CCT were of no significant difference. However, the diagnostic specificity of ARR>7.12 combined with hypokalemia was up to 80%. Conclusion: ARR before or after CCT have clinical value for the diagnosis of APA from PA, when combined with hypokalemia yielded high specificity.