Update on Primary Aldosteronism: Time to Screen All Hypertensives.

Primary aldosteronism (PA), characterized by autonomous renin-independent aldosterone production, is the most common endocrine cause of hypertension.1 PA was initially considered a rare cause of secondary hypertension, as experts described 0.451% prevalence in mild to moderate hypertension when hypokalemia was an essential reason for screening.1 However, recent data suggests that PA may be present even in patients with normokalemia, and 515% of patients in the hypertensive cohort have underlying overt PA.2.

Resident-led improvement project to screen for primary hyperaldosteronism in patients with resistant hypertension in an outpatient clinic.

Clinical practice guidelines recommend screening for primary hyperaldosteronism (PH) in patients with resistant hypertension. However, screening rates are low in the outpatient setting. We sought to increase screening rates for PH in patients with resistant hypertension in our Veterans Affairs (VA) outpatient resident physician clinic, with the goal of improving blood pressure control. Patients with possible resistant hypertension were identified through a VA Primary Care Almanac Metric query, with subsequent chart review for resistant hypertension criteria. Three sequential patient-directed cycles were implemented using rapid cycle improvement methodology during a weekly dedicated resident quality improvement half-day. In the first cycle, patients with resistant hypertension had preclinic PH screening labs ordered and were scheduled in the clinic for hypertension follow-up. In the second cycle, patients without screening labs completed were called to confirm medication adherence and counselled to screen for PH. In the third cycle, patients with positive screening labs were called to discuss mineralocorticoid receptor antagonist (MRA) initiation and possible endocrinology referral. Of 97 patients initially identified, 58 (60%) were found to have resistant hypertension while 39 had pseudoresistant hypertension from medication non-adherence. Of the 58 with resistant hypertension, 44 had not previously been screened for PH while 14 (24%) had already been screened or were already taking an MRA. Our screening rate for PH in resistant hypertension patients increased from 24% at the start of the project to 84% (37/44) after two cycles. Of the 37 tested, 24% (9/37) screened positive for PH, and 5 patients were started on MRAs. This resident-led quality improvement project demonstrated that a focused intervention process can improve PH identification and treatment.

Surgical versus medical management of patients with primary hyperaldosteronism and indeterminate adrenal vein sampling: A 10-year experience of the Cleveland Clinic.

In patients with primary hyperaldosteronism (PA), adrenal vein sampling (AVS) can identify patients suitable for unilateral adrenalectomy. However, in AVS with an indeterminate aldosterone-to-cortisol lateralization (ACL) ratio of 3.0-4.0, clinical guidance is unclear. The authors screened all patients undergoing AVS at the Cleveland Clinic from October 2010 to January 2021 and identified 18 patients with indeterminate ACL results. Ten underwent adrenalectomy and eight continued medical management. The surgical group was younger (58.5 vs. 68 years, p = .17), and more likely to have a unilateral imaging adrenal abnormality (90% vs. 38%, p = .043) and a lower contralateral suppression index (0.63 vs. 1.1, p = .14). Post-treatment, the surgical group had a significant reduction in diastolic blood pressure (-5.5 mmHg, p = .043) and aldosterone (4.40 vs. 35.80 ng/mL, p = .035) and required fewer anti-hypertensive medications (2 vs. 3, p = .015). These findings may support the benefit of adrenalectomy in a select group of patients with indeterminate ACL.

[Clinical characteristics and prognosis of primary aldosteronism associated with subclinical Cushing syndrome].

Objective: To analyze the clinical characteristics and prognosis of patients with primary aldosteronism (PA) associated with subclinical Cushing syndrome (SCS). Methods: This retrospective cohort study was conducted at the First Affiliated Hospital of Chongqing Medical University in China. Patients with PA were included between January 2014 and December 2022. According to the results of 1-mg overnight dexamethasone suppression test, the patients were divided into the PA group and PA associated with SCS (PA/SCS) group. The demographic information, hormone levels, and follow-up results were analyzed. Independent sample t-test, chi-square test and Mann-Whitney U test were used for data comparison. Results: A total of 489 PA patients were enrolled in this study, of which 109 had PA/SCS (22.3%). Patients with SCS were on average older (54.4±10.7 vs. 47.4±11.0, P<0.001); had a larger proportion of women (69.7%, 76/109 vs. 57.4%, 218/380; P=0.020); and a longer duration of hypertension [96 (36, 180) vs. 60 (12, 120) months, P=0.001] than patients without SCS. There were 215 and 51 patients in the PA group and PA/SCS group, who completed adrenalectomy and follow-up, respectively. The remission rate of autonomous cortisol secretion in the PA/SCS group was 85.3% (29/34). There was no significant difference in the remission rate of autonomous aldosterone secretion among patients between the PA/SCS and PA group (94.1%, 48/51 vs. 94.4%, 203/215; P=1.000), while the clinical remission rate in the PA/SCS group was lower than that in the PA group (39.2%, 20/51 vs. 61.9%, 133/215; P=0.003). Conclusions: SCS is common in PA patients (22.3%), and the clinical remission rate is low. Screening using the 1-mg overnight dexamethasone suppression test is recommended for all patients with PA.

Comparison of saline infusion test and captopril challenge test in the diagnosis of Chinese with primary aldosteronism in different age groups.

Background: To explore the diagnostic accuracy and the optimal cutoff value between the saline infusion test (SIT) and captopril challenge test (CCT) [including the value and suppression of plasma aldosterone concentration (PAC)] for primary aldosteronism (PA) diagnosing. Methods: A total of 318 patients with hypertension were consecutively enrolled, including 126 patients with PA and 192 patients with essential hypertension (EH), in this observational study. The characteristics of patients and laboratory examinations were collected and compared. The comparison between SIT and CCT was carried by drawing the receiver operator characteristic curve (ROC) and calculating the area under the curve (AUC) to explore the diagnostic accuracy and the optimal cutoff value. Results: The average age was 51.59 ± 10.43 in the PA group and 45.72 ± 12.44 in the EH group (p<0.05). The optimal cutoff value was 10.7 ng/dL for post-CCT PAC, 6.8 ng/dL for post-SIT PAC, and 26.9% for suppression of post-CCT PAC. The diagnostic value of post-CCT PAC was the highest with 0.831 for the AUC and 0.552 for the Youden index. The optimal cutoff value for patients who were <50 years old was 11.5 ng/dL for post-CCT PAC and 8.4 ng/dL for post-SIT PAC. The suppression of post-CCT PAC turned to 18.2% for those of age 50 or older. Conclusion: Compared with SIT, CCT had a higher diagnostic value when post-CCT PAC was used as the diagnostic criterion in Chinese people, while the selection of diagnostic thresholds depended on patient age.

Familial hyperaldosteronism: an European Reference Network on Rare Endocrine Conditions clinical practice guideline.

We describe herein the European Reference Network on Rare Endocrine Conditions clinical practice guideline on diagnosis and management of familial forms of hyperaldosteronism. The guideline panel consisted of 10 experts in primary aldosteronism, endocrine hypertension, paediatric endocrinology, and cardiology as well as a methodologist. A systematic literature search was conducted, and because of the rarity of the condition, most recommendations were based on expert opinion and small patient series. The guideline includes a brief description of the genetics and molecular pathophysiology associated with each condition, the patients to be screened, and how to screen. Diagnostic and treatment approaches for patients with genetically determined diagnosis are presented. The recommendations apply to patients with genetically proven familial hyperaldosteronism and not to families with more than one case of primary aldosteronism without demonstration of a responsible pathogenic variant.

Evaluation of screening practices for primary hyperaldosteronism by specialists and general practitioners: an observational, cross-sectional study.

Objective: Despite its recognized importance, primary hyperaldosteronism (PHA) remains an underdiagnosed condition in clinical practice. The objective of the present study was to evaluate PHA screening practices by general practitioners and specialists in endocrinology and cardiology. Subjects and methods: This cross-sectional, observational study invited physicians to respond voluntarily to an online survey. The survey collected the respondents' sociodemographic data and answers to five hypothetical clinical cases meeting Endocrine Society criteria for PHA screening. Results: In all, 126 physicians responded to the online survey. Endocrinologists were the specialists who most often chose PHA screening, although the screening rates were overall low, ranging from 36.5% to 92.9%, depending on the case and the respondents' specialty. The survey also assessed the reasons for not choosing PHA screening, which included limited availability of tests within the public health services, interference of antihypertensive medications on hormone levels, and failure to identify the screening indication. Being an endocrinologist was an independent predictor for choosing PHA screening for the patients in Cases #1 and #5 (p = 0.001 and p = 0.002, respectively). Conclusion: Endocrinologists were the specialists who most often chose PHA screening, although the screening rates were overall low among all specialists. These findings highlight a need for continuing medical education programs addressing PHA screening and making the diagnosis of PHA more present in the daily clinical practice of physicians treating patients with hypertension.

Conn´s syndrome after kidney transplantation.

Conn's syndrome, defined as unilateral aldosterone-producing adenoma, accounts for 35-40% of cases of primary hyperaldosteronism. Primary hyperaldosteronism typically occurs in younger patients with poorly controlled arterial hypertension due to extracellular fluid retention, in whom at least a triple combination of antihypertensives, including a diuretic, is needed to maintain normotension. The clinical picture of arterial hypertension may be complemented by symptoms associated with hypokalaemia, such as weakness, fatigue, palpitations, convulsions, polydipsia, or polyuria. In addition to arterial hypertension and hypokalaemia, the diagnosis of Conn's syndrome relies on examination of serum renin and aldosterone concentrations, plasma renin activity, exercise or furosemide stimulation tests, and imaging studies, preferably computed tomography. The method of treatment of Conn's syndrome is adrenalectomy. In patients with primary hyperaldosteronism with underlying bilateral adrenal cortical hyperplasia or patients contraindicated for surgery, mineralocorticoid receptor antagonists are administered in combination with antihypertensives targeted for optimal blood pressure control.In the group of patients after kidney transplantation, the exact incidence of primary hyperaldosteronism is unknown. Based on a cross-sectional study performed in 2020, it is estimated to be approximately 15% in the group of patients with unsatisfactorily compensated arterial hypertension; in the cohort of normotensive recipients, the incidence of primary hyperaldosteronism is not documented. Diagnosis of Conn's syndrome in patients in the early period after kidney transplantation is problematic, as the prevalence of arterial hypertension in transplanted patients is high (70-90%) according to the literature. Mineral abnormalities, including hypokalaemia, are also common in the early post-transplant period, mainly due to factors such as duration of cold ischaemia, onset of graft function, donor parameters, post-transplant tubulopathy, and diuretics, the effects of immunosuppressive drugs (especially calcineurin inhibitors and corticosteroids), and possibly potassium-restricted dietary habits that the patient brings from the pre-transplant period, which may mask the effect of hyperaldosteronism on potassium.We present the case of a patient who was diagnosed with Conn's syndrome 7 months after primary kidney transplantation from a deceased donor based on persistent hypokalaemia unresponsive to replacement therapy. At the time of the first manifestation of severe hypokalaemia, the patient was treated with a dual combination of antihypertensives (amlodipine at a daily dose of 5 mg and carvedilol at a daily dose of 50 mg), without the need for a diuretics.We consider the case interesting because the spectrum of mineral and acid-base abnormalities in advanced renal failure and in the early post-transplant period, as well as acid-base and mineral imbalances, including hypokalaemia, and the high prevalence of arterial hypertension in the post-transplant period, may mask the picture of Conn's syndrome (Fig. 3, Ref. 19). Text in PDF www.elis.sk Keywords: kidney transplantation, primary hyperaldosteronism, hypokalaemia, metabolic alkalosis, secondary arterial hypertension.

Effect of adrenocorticotropic hormone stimulation during adrenal vein sampling for the subtyping of primary aldosteronism: a prospective study.

OBJECTIVE: Adrenal venous sampling (AVS) is key for primary aldosteronism subtype identification. However, the value of adrenocorticotropic hormone (ACTH) stimulation in AVS is still controversial. METHODS: In this prospective study, we investigated the role of continuous ACTH infusion on the performance and interpretation of bilateral simultaneous AVS using a standard protocol in 59 primary aldosteronism patients. We analyzed the selectivity index and lateralization index in AVS pre and post-ACTH and estimated the prognosis of patients who underwent adrenalectomy with different cutoff points of lateralization index post-ACTH. RESULTS: The confirmed success rate of bilateral adrenal vein catheterization increased from 84% pre-ACTH to 95% post-ACTH. Fifty percent of the patients had a decline in lateralization index post-ACTH, 30% of patients showed unilateral primary aldosteronism pre-ACTH but bilateral primary aldosteronism post-ACTH according to lateralization index at least 2 pre-ACTH and lateralization index at least 4 post-ACTH. The outcomes of the patients with primary aldosteronism after adrenalectomy indicated that all patients achieved clinical and biochemical success regardless of lateralization index at least 4 or less than 4 post-ACTH. Receiver operating characteristic curves showed that lateralization index cutoff 2.58 post-ACTH stimulation yielded the best threshold in lateralization with a sensitivity of 73.1% and a specificity of 92.9%. CONCLUSION: ACTH stimulation increased the AVS success rates in patients with primary aldosteronism, reduced lateralization index in some cases and decreased the proportion of identified unilateral primary aldosteronism, resulting in some patients losing the opportunity for disease cure. Compared with lateralization index at least 4, a lower cutoff point of lateralization index at least 2.58 after ACTH stimulation has better accuracy of lateralization diagnosis.

Untargeted metabolomics reveals potential plasma biomarkers for diagnosis of primary aldosteronism using liquid chromatography-mass spectrometry.

Metabolite profiling has the potential to comprehensively bridge phenotypes and complex heterogeneous physiological and pathological states. We performed a metabolomics study using parallel liquid chromatography-mass spectrometry (LC-MS) combined with multivariate data analysis to screen for biomarkers of primary aldosteronism (PA) from a cohort of 111 PA patients and 218 primary hypertension (PH) patients. Hydrophilic interaction chromatography and reversed-phase liquid chromatography separations were employed to obtain a global plasma metabolome of endogenous metabolites. The satisfactory classification between PA and PH patients was obtained using the MVDA model. A total of 35 differential metabolites were screened out and identified. A diagnostic biomarker panel was established using the least absolute shrinkage and selection operator (LASSO) binary logistic regression model and receiver operating characteristic analysis. Joint analysis with clinical indicators, including plasma supine aldosterone level, plasma orthostatic aldosterone level, body mass index, and blood potassium, revealed that the combination of metabolite biomarker panel and plasma supine aldosterone has the best clinical diagnostic efficacy.

Laboratory Testing for Endocrine Hypertension: Current and Future Perspectives.

BACKGROUND: Secondary hypertension (SH) is a form of high blood pressure caused by an identifiable underlying condition. Although, it accounts for a small fraction of the overall hypertensive population, detection and management of SH is of utmost importance, because SH phenotypes carry a high cardiovascular risk and can possibly be cured by timely treatment. CONTENT: This review focuses on the endocrine causes of SH, such as primary aldosteronism, Cushing syndrome, thyroid disease, pheochromocytoma and paraganglioma, acromegaly, and rare monogenic forms. It discusses current biomarkers, analytical methods, and diagnostic strategies, highlighting advantages and limitations of each approach. It also explores the emerging -omics technologies that can provide a comprehensive and multidimensional assessment of SH and its underlying mechanisms. SUMMARY: Endocrine SH is a heterogeneous and complex condition that requires proper screening and confirmatory tests to avoid diagnostic delays and improve patient outcomes. Careful biomarker interpretation is essential due to potential interferences, variability, and method-dependent differences. Liquid chromatography-tandem mass spectrometry is a superior method for measuring low-concentration hormones and metabolites involved in SH, but it requires expertise. Omics approaches have great potential to identify novel biomarkers, pathways, and targets for SH diagnosis and treatment, especially considering its multifactorial nature.

Subtype Identification of Surgically Curable Primary Aldosteronism During Treatment With Mineralocorticoid Receptor Blockade.

BACKGROUND: Current guidelines and consensus documents recommend withdrawal of mineralocorticoid receptor antagonists (MRAs) before primary aldosteronism (PA) subtyping by adrenal vein sampling (AVS), but this practice can cause severe hypokalemia and uncontrolled high blood pressure. Our aim was to investigate if unilateral PA can be identified by AVS during MRA treatment. METHODS: We compared the rate of unilateral PA identification between patients with and without MRA treatment in large data sets of patients submitted to AVS while off renin-angiotensin system blockers and ß-blockers. In sensitivity analyses, the between-group differences of lateralization index values after propensity score matching and the rate of unilateral PA identification in subgroups with undetectable (≤2 mUI/L), suppressed (<8.2 mUI/L), and unsuppressed (≥8.2 mUI/L) direct renin concentration levels were also evaluated. RESULTS: Plasma aldosterone concentration, direct renin concentration, and blood pressure values were similar in non-MRA-treated (n=779) and MRA-treated (n=61) patients with PA, but the latter required more antihypertensive agents (P=0.001) and showed a higher rate of adrenal nodules (82% versus 67%; P=0.022) and adrenalectomy (72% versus 54%; P=0.01). However, they exhibited no significant differences in commonly used AVS indices and the area under the receiving operating characteristic curve of lateralization index, both under unstimulated conditions and postcosyntropin. Several sensitivity analyses confirmed these results in propensity score matching adjusted models and in patients with undetectable, or suppressed or unsuppressed renin levels. CONCLUSIONS: At doses that controlled blood pressure and potassium levels, MRAs did not preclude the identification of unilateral PA at AVS. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01234220.

Investigating the cut-off values of captopril challenge test for primary aldosteronism using the novel chemiluminescent enzyme immunoassay method: a retrospective cohort study.

The measurement evolution enabled more accurate evaluation of aldosterone production in hypertensive patients. However, the cut-off values for novel assays have been not sufficiently validated. The present study was undertaken to validate the novel chemiluminescent enzyme immunoassay for aldosterone in conjunction with other methods. Moreover, we also aimed to establish a new cut-off value for primary aldosteronism in the captopril challenge test using the novel assay. First, we collected 390 plasma samples, in which aldosterone levels measured using liquid chromatography-mass spectrometry ranged between 0.18 and 1346 ng/dL. The novel chemiluminescent enzyme immunoassay showed identical correlation of plasma aldosterone with liquid chromatography-mass spectrometry, in contrast to conventional radioimmunoassay. Further, we enrolled 299 and 39 patients with primary aldosteronism and essential hypertension, respectively. Plasma aldosterone concentrations measured using the novel assay were lower than those measured by radioimmunoassay, which resulted in decreased aldosterone-to-renin ratios. Subsequently, positive results of the captopril challenge test based on radioimmunoassay turned into "negative" based on the novel assay in 45% patients with primary aldosteronism, using the conventional cut-off value (aldosterone-to-renin activity ratio > 20 ng/dL per ng/mL/h). Receiver operating characteristic curve analysis demonstrated that aldosterone-to-renin activity ratios > 8.2 ng/dL per ng/mL/h in the novel assay was compatible with the conventional diagnosis (sensitivity, 0.874; specificity, 0.980). Our study indicates the great measurement accuracy of the novel chemiluminescent enzyme immunoassay for aldosterone, and the importance of measurement-adjusted cut-offs in the diagnosis of primary aldosteronism.

A comparison of the performance of 68Ga-Pentixafor PET/CT versus adrenal vein sampling for subtype diagnosis in primary aldosteronism.

Objective: To investigate the diagnostic efficiency and prognostic value of 68Ga-Pentixafor PET/CT in comparison with adrenal vein sampling (AVS) for functional lateralization in primary aldosteronism (PA). Histology and long-term clinical follow-up normally serve as the gold standard for such diagnosis. Methods: We prospectively recruited 26 patients diagnosed with PA. All patients underwent 68Ga-Pentixafor PET/CT and AVS. Postsurgical biochemical and clinical outcomes of patients with unilateral primary aldosteronism (UPA), as diagnosed by PET/CT or AVS, were assessed by applying standardized Primary Aldosteronism Surgical Outcome (PASO) criteria. Immunohistochemistry (IHC) was performed to detect the expression of aldosterone synthase (CYP11B2) and CXCR4. Results: On total, 19 patients were diagnosed with UPA; of these, 13 patients were lateralized by both PET/CT and AVS, four patients were lateralized by PET-only, and two by AVS-only. Seven subjects with no lateralization on AVS and PET received medical therapy. All patients achieved complete biochemical success except one with nodular hyperplasia lateralized by AVS alone. The consistency between PET/CT and AVS outcomes was 77% (20/26). Moreover, CYP11B2-positive nodules were all CXCR4-positive and showed positive findings on PET. Patients who achieved complete biochemical and clinical success had a higher uptake on PET as well as stronger expression levels of CXCR4 and CYP11B2. Conclusion: Our analysis showed that 68Ga-Pentixafor PET/CT could enable non-invasive diagnosis in most patients with PA and identify additional cases of unilateral and surgically curable PA which could not be classified by AVS. 68Ga-Pentixafor PET/CT should be considered as a first-line test for the future classification of PA.

[Comparison of Different Doses of ACTH Used in ACTH Stimulation Test to Determine the Subtypes of Primary Aldosteronism]. / ä¸åŒå‰‚é‡ä¿ƒè‚¾ä¸Šè ºçš®è´¨æ¿€ç´ å ´å¥‹è¯•éªŒåœ¨åŽŸå‘æ€§é†›å›ºé ®å¢žå¤šç—‡åˆ†åž‹è¯Šæ–­ä¸­çš„æ¯”è¾ƒ.

Objective: To compare the diagnostic value of adrenocorticotropic hormone (ACTH) stimulation test (AST) with different doses of ACTH combined with midnight administration of 1 mg dexamethasone for the determination of the subtypes of primary hyperaldosteronism (PA). Methods: This is a prospective observational study. Patients diagnosed with PA in the Department of Endocrinology, the First Medical Center of of Chinese PLA General Hospital from January 1, 2020 to September 30, 2022 underwent AST with different doses of ACTH. All patients received 1 mg dexamethasone at midnight for inhibition. Then, the patients were randomly assigned to 25-unit and 50-unit ACTH treatment groups by a ratio of 1:2. Subtype classification and diagnosis of aldosterone-producing adenoma (APA) and idiopathic hyperaldosteronism (IHA) was made on the basis of adrenal venous blood samples and/or postoperative pathology and clinical follow-up findings. Receiver operating characteristics (ROC) curves were plotted to examine the diagnostic efficacy and the difference of AST by varying doses of ACTH in distinguishing APA and IHA. Results: A total of 82 patients, including 49 patients with APA (59.8%) and 33 patients with IHA (40.2%), were enrolled. There were 29 patients in the 25-unit ACTH group (35.4%) and 53 patients in the 50-unit ACTH group (64.6%). There were no significant differences in age, sex, blood pressure, minimum serum potassium, and biochemical parameters between the 25-unit and 50-unit groups. After ACTH stimulation, plasma aldosterone concentration (PAC), cortisol (F), and PAC/F at different points of time showed no statistical difference between the two groups (P>0.05). The area under the curve (AUC) of PAC in the 25-unit group was higher than that of PAC/F. The AUC of PAC reached the maximum at 90 minutes (0.948, 95% confidence interval [CI]: 0870-1.000) and the optimal cutoff was 38.0 ng/dL, which had a sensitivity of 92.9% and a specificity of 86.7% for differentiating APA and IHA. Similar to the 25-unit group, the maximum AUC of PAC in the 50-unit group was greater than that of PAC/F. The AUC of PAC reached the maximum 90 minutes (0.930, 95% CI: 0.840-0.994) and the optimal cutoff was 39.6 ng/dL, which had a sensitivity of 91.2% and a specificity of 83.3%. The AUC of PAC at different points of time in the 25-unit ACTH group (0.862-0.948) was greater than that of 50-unit ACTH group (0.823-0.930), but the difference was not statistical significance. Conclusion: AST with 25-unit or 50-unit ACTH combined with small-dose dexamethasone can be used in PA subtype determination, ie, differentiation between APA and IHA. The optimal PAC cut-off values for 25-unit or 50-unit ACTH are similar, being 38.0 ng/dL and 39.6 ng/dL, respectively, and both cutoff values show higher sensitivity and specificity at 90 min. The AST with 25-unit ACTH has the smaller dose and the better safety. Therefore, it is recommended for the diagnosis of PA subtypes.

MicroRNAs in aldosterone production and action.

Aldosterone is a cardiovascular hormone with a key role in blood pressure regulation, among other processes, mediated through its targeting of the mineralocorticoid receptor in the renal tubule and selected other tissues. Its secretion from the adrenal gland is a highly controlled process subject to regulatory influence from the renin-angiotensin system and the hypothalamic-pituitary-adrenal axis. MicroRNAs are small endogenous non-coding RNA molecules capable of regulating gene expression post-transcriptionally through stimulation of mRNA degradation or suppression of translation. Several studies have now identified that microRNA levels are changed in cases of aldosterone dysregulation and that microRNAs are capable of regulating the expression of various genes involved in aldosterone production and action. In this article we summarise the major studies concerning this topic. We also discuss the potential role for circulating microRNAs as diagnostic biomarkers for primary aldosteronism, a highly treatable form of secondary hypertension, which would be highly desirable given the current underdiagnosis of this condition.

A 120-Minute Saline Infusion Test for the Confirmation of Primary Aldosteronism: A Pilot Study.

BACKGROUND: The saline infusion test (SIT) to confirm primary aldosteronism requires infusing 2 L of normal saline over 240 minutes. Previous studies raised concerns regarding increased blood pressure and worsening hypokalemia during SIT. We aimed to evaluate the diagnostic applicability of a SIT that requires 1 L of saline infusion over 120 minutes. METHODS: A cross-sectional study, including all patients in a large medical center who underwent SIT from 1 January 2015 to 30 April 2023. Blood samples were drawn for baseline renin and aldosterone (t = 0) after 2 hours (t = 120 min) and after 4 hours (t = 240 min) of saline infusion. We used ROC analysis to evaluate the sensitivity and specificity of various aldosterone cut-off values at t = 120 to confirm primary aldosteronism. RESULTS: The final analysis included 62 patients. A ROC analysis yielded 97% specificity and 90% sensitivity for a plasma aldosterone concentration (PAC) of 397 pmol/L (14 ng/dL) at t = 120 to confirm primary aldosteronism, and an area under the curve of 0.97 (95% CI [0.93, 1.00], P < 0.001). Almost half (44%) of the patients did not suppress PAC below 397 pmol/L (14 ng/dL) at t = 120. Of them, only one (4%) patient suppressed PAC below 276 pmol/L (10 ng/dL) at t = 240. Mean systolic blood pressure increased from 140.1 ±â€…21.3 mm Hg at t = 0 to 147.6 ±â€…14.5 mm Hg at t = 240 (P = 0.011). CONCLUSIONS: A PAC of 397 pmol/L (14 ng/dL) at t = 120 has high sensitivity and specificity for primary aldosteronism confirmation.