ABSTRACT
Primary aldosteronism(PA) is one of the most common causes of secondary hypertension,plasma aldosterone concentration(PAC)/plasma renin activity (PRA) ratio is widely used in clinical practice.However,PRA reflects the level of plasma renin indirectly.In recent years,plasma renin concentration (PRC) has been measured by automatic chemiluminescence immunoassay,which is more stable,convenient and with less confounding factors than conventional renin activity.This review briefly introduces methods of examining PRA,PRC and PAC,and compares the value of PAC/PRC ratio with PAC/PRA ratio in PA detection.
ABSTRACT
Objective To explore the best way for clinical screening of primary aldosteronism (PA).Methods Three hundred and three suspected cases of PA were collected and divided into groups of primary aldosteronism group, essential hypertension group, and nonsecreting cortical adrenal tumor group.The plasma aldosterone concentration/plasma renin concentration ratio ( ARR) was used to draw the receiver operating characteristic ( ROC) curve and obtain the best cut-off point.Furthermore, the current screening schemes for PA were compared.Results Upright ARR yield had larger areas under the ROC curve than plasma aldosterone concentration or plasma renin concentration under all conditions of testing. The best cut-off point of upright ARR[(pg/ml)/(μIU/ml)] for the diagnosis of PA was 43.45.During the two postural stimulation tests,the two upright ARR exceeded 43.45 with the highest diagnostic sensitivity of PA reaching 0.94.During the two upright tests ARR was less than 43.45, with a sensitivity of 0.74, and a specificity of 0.94.Conclusion To screen for PA in high-risk populations, twice postural stimulation test is recommended.As long as the upright ARR is above 43.45, PA may be considered and further confirmation is needed to prevent misdiagnosis.
ABSTRACT
Primary aldosteronism (PA) is characterized by inappropriately high production of aldosterone relatively autonomous from the renin-angiotensin system and no suppression by sodium loading. The prevalence of PA is estimated more than 10% among nonseleted hypertensive patients. PA is clinically very important since patients with PA have higher cardiovascular morbidity and mortality than age- and sex-matched patients with essential hypertension and the same degree of blood pressure elevation. The ratio of plasma aldosterone concentration to plasma renin activity (ARR) has been generally accepted as a first-line screening test. ARR might be affected by patient age, anti-hypertensive drugs, posture and menstrual cycles. Once the ARR is measured, confirmative test should be performed. Although a gold standard confirmative test for PA is not yet identified, intravenous saline loading test is widely used. Adrenal venous sampling (AVS) is a gold standard for differentiation of unilateral from bilateral forms of PA. Since adrenal CT imaging has limitations to accurate diagnosis of PA, AVS is recommended for all patients who wish to pursue surgical treatment. Although unilateral laparoscopic adernalectomy is the optimal treatment for patients with aldosterone producing adenoma or unilateral hyperplasia, strong evidence linking adernalectomy with improved quality of life, morbidity or mortality is not available. Mneralocorticoid receptor antagonists, spironolactone or eplerenone, are recommended for pharmacologic therapy of PA.