静脉盐水负荷试验在原发性醛固酮增多症诊断中的应用

目的探讨静脉盐水负荷试验在原发性醛固酮增多症(原醛症)诊断中的应用价值。方法2004~2006年临床确诊原醛症患者65例,其中醛固酮瘤27例,特发性醛固酮增多症(特醛症)26例,原发性肾上腺增生11例,醛固酮癌1例。所有患者检测血电解质,血、尿醛固酮及立位血浆肾素活性等生化指标,同时行静脉盐水负荷试验。以19例原发性高血压患者作为对照组。结果与对照组比较,原醛症组患者的血、尿醛固酮明显升高,而血钾及立位血浆肾素活性则低;原醛症组和对照组静脉盐水负荷后血醛固酮不能抑制者分别为95.4%(62/65)和21.1%(4/19);该试验对原醛症诊断的敏感性和特异性分别为95.4%和93.9%。65例原醛症患者中,醛固酮瘤和原发性肾上腺增生患者的血钾较特醛症患者低,而血、尿醛固酮则高;醛固酮瘤、特醛症、原发性肾上腺增生及醛固酮癌患者的静脉盐水负荷后血醛固酮的抑制率分别为16.1%、28.9%、15.4%和5.2%。结论原发性肾上腺增生患者生化指标改变与醛固酮瘤患者类似,均较特醛症患者更为明显。静脉盐水负荷试验是一项安全且可靠的原醛症确诊方法,其敏感性和特异性均较高。

Value of saline load test in diagnosis of primary aldosteronism

Objective To investigate the value of i.v. saline load test (SLT) in the diagnosis of primary aldosteronism (PA). MethodsFrom 2004 to 2006, 65 patients clinically diagnosed with PA (27 APA, 26 IHA, 11 PAH and 1 CA) were examined with plasma and urinary aldosterone, upright plasma renin activity (PRA) and electrolyte. All of them were performed i.v. SLT. Nineteen patients with essential hypertension (EH) were served as controls. Results Compared with the controls, the patients with PA had higher plasma and urinary aldosterone, lower serum potassium and upright PRA. Those whose plasma aldosterone could not be suppressed after i.v. SLT accounted for 95.4%(62/65)and 21.1%(4/19), respectively in the PA group and control group, and the sensitivity and specificity of SLA for PA was 95.4% and 93.9%. The patients with APA and PAH had lower serum potassium and higher plasma and urinary aldosterone than those with IHA. The inhibition rates of plasma aldosterone after i.v. SLT were 16.1%, 28.9%, 15.4% and 5.2%, respectively, for those with APA, IHA, PAH and CA. Conclusion The laboratory anomalies of patients with APA and PAH are similar and are more evident than those with IHA. The i.v. SLT is a safe and reliable confirmatory test for the diagnosis of PA with a high sensitivity and specificity.