Primary aldosteronism: diagnostic and treatment strategies

Follow-up care and assessment of comorbidities and complications in patients with primary aldosteronism: The clinical practice guideline of the Taiwan Society of aldosteronism

Primary aldosteronism (PA) is the most common form of endocrine hypertension, characterized by excess aldosterone production that leads to an increased risk of cardiovascular events and target organ damage. Both adrenalectomy and medical treatment have shown efficacy in improving clinical outcomes and comorbidities associated with PA, including a specific subtype of PA with autonomous cortisol secretion (ACS). Understanding the comorbidities of PA and establishing appropriate follow-up protocols after treatment are crucial for physicians to enhance morbidity and mortality outcomes in patients with PA. Additionally, the screening for hypercortisolism prior to surgery is essential, as the prognosis of patients with coexisting PA and ACS differs from those with PA alone. In this review, we comprehensively summarize the comorbidities of PA, encompassing cardiovascular, renal, and metabolic complications. We also discuss various post-treatment outcomes and provide insights into the strategy for glucocorticoid replacement in patients with overt or subclinical hypercortisolism. This clinical practice guideline aims to equip medical professionals with up-to-date information on managing concurrent hypercortisolism, assessing treatment outcomes, and addressing comorbidities in patients with PA, thereby improving follow-up care.

2023 Korean Endocrine Society Consensus Guidelines for the Diagnosis and Management of Primary Aldosteronism

Primary aldosteronism (PA) is a common, yet underdiagnosed cause of secondary hypertension. It is characterized by an overproduction of aldosterone, leading to hypertension and/or hypokalemia. Despite affecting between 5.9% and 34% of patients with hypertension, PA is frequently missed due to a lack of clinical awareness and systematic screening, which can result in significant cardiovascular complications. To address this, medical societies have developed clinical practice guidelines to improve the management of hypertension and PA. The Korean Endocrine Society, drawing on a wealth of research, has formulated new guidelines for PA. A task force has been established to prepare PA guidelines, which encompass epidemiology, pathophysiology, clinical presentation, diagnosis, treatment, and follow-up care. The Korean clinical guidelines for PA aim to deliver an evidence-based protocol for PA diagnosis, treatment, and patient monitoring. These guidelines are anticipated to ease the burden of this potentially curable condition.

Usefulness of Alternative Therapy with Hydrocortisone in the Postoperative Management of Severe Primary Aldosteronism

Mineralocorticoid deficiency (MD) with hyperkalemia is an important complication of adrenalectomy in patients with primary aldosteronism (PA). We herein report a 52-year-old man with refractory hypertension, hypokalemia, and severe renal dysfunction due to PA caused by a right adrenal adenoma. His estimated glomerular filtration rate (eGFR) transiently increased immediately after adrenalectomy but then gradually declined, and he developed hyperkalemia. A postoperative endocrine examination revealed MD. Considering the patient's hypertension and severe renal dysfunction, we administered hydrocortisone instead of fludrocortisone, which improved the hyperkalemia and stopped the decline in the eGFR. Alternative therapy with hydrocortisone may be useful in such patients with MD.

Anesthetic Implications in Managing a Case of Primary Hyperaldosteronism: A Case Report

Primary hyperaldosteronism (also called Conn's syndrome) is a rare condition of the adrenal glands characterized by excessive secretion of the hormone aldosterone, which regulates the balance of water and electrolytes in the body, and maintains blood volume and pressure. Hyperaldosteronism causes sodium and water retention, hypokalemia, hypertension, and muscle weakness. Common cause of primary hyperaldosteronism is an adrenal adenoma or bilateral adrenal hyperplasia. A 36-year-old female presented with hypertension, hypokalemia and muscle cramps, and on further evaluation by computed tomography (CT) scan was found to have a right adrenal adenoma. She was scheduled for a right-sided laparoscopic adrenalectomy. We report the successful peri-operative anesthetic management of this patient who had an uneventful intra-operative and post-operative course.

Left adrenal aldosteronism coexisting with left paraaortic paraganglioma presenting as bilateral adrenal and left paraaortic tumors- comprehensive adrenal evaluation aiding perfect management: a case report

BACKGROUND

Coexistence of a catecholamine-secreting tumor and an adrenal cortical tumor is quite rare which makes both diagnosis and management challenging. The purpose of this article is to describe the presence of this condition, share a stepwise approach for preoperative evaluation, and review the related literature.

CASE PRESENTATION

A 44-year-old male patient had a history of hypertension and aggravating hypokalemia for years. Abdominal computed tomography incidentally found concomitant bilateral adrenal and left para-aortic tumors. Comprehensive adrenal hormone tests revealed a high aldosterone renin ratio and mildly elevated 24-h urine vanillylmandelic acid and norepinephrine levels. Subsequently, a metaiodobenzylguanidine scan showed uptake over the left para-aortic tumor, and NP-59 adrenal scintigraphy showed uptake over the left adrenal tumor. Further confirmatory tests, including captopril suppression, irbesartan suppression, and saline infusion, all confirmed the diagnosis of hyperaldosteronism. Adrenal venous sampling following 2 months of preparation with an alpha blocker demonstrated a left aldosterone-producing adrenal adenoma. Combining hormonal analysis, imaging studies, and adrenal venous sampling, the patient was diagnosed with left adrenal aldosteronoma, right adrenal nonfunctional tumor, and left para-aortic paraganglioma (PGL). Accordingly, laparoscopic left adrenalectomy and left PGL excision were performed smoothly under alpha blocker maintenance. The pathology report confirmed left adrenal cortical adenoma and left para-aortic PGL. Postoperatively, the blood pressure, biochemical tests, and adrenal hormone assays returned to normal, and related symptoms disappeared and were relatively stable during the follow-up period of two years.

CONCLUSIONS

This is the first case of left para-aortic PGL coexisting with an ipsilateral aldosterone-producing adenoma presenting as a left para-aortic tumor associated with bilateral adrenal tumors. Awareness of the rarity of this coexistence can avoid unexpected disasters during the process of evaluation and management.

Screening for primary aldosteronism is underutilised in patients with chronic kidney disease

BACKGROUND

Primary aldosteronism (PA) is the most common and potentially curable endocrine cause of secondary hypertension, and carries a worse prognosis than essential hypertension. Despite the high prevalence of hypertension in patients with chronic kidney disease (CKD), the screening rates for primary aldosteronism in CKD are unknown.

METHODS

In this study, we retrospectively reviewed medical records of 1627 adults who presented to the nephrology clinics of 2 tertiary hospitals in Melbourne, Australia, between 2014 and 2019. In addition to assessing the pattern of screening, we also evaluated patient-specific factors associated with the decision to test for primary aldosteronism. Patients were excluded from the final analysis if they did not have CKD, had an organ transplant, had end stage renal failure, or had insufficient data or follow-up.

RESULTS

Of the 600 patients included in the analysis, 234 (39%) had an indication for screening for primary aldosteronism based on recommendations made by the Endocrine Society. However, only 33 (14%) were tested. They were younger, had a higher mean systolic blood pressure, better renal function, and lower mean serum potassium than those who were indicated but not screened. Of the 33 screened patients, an elevated aldosterone-to-renin ratio was noted in 8 patients and a diagnosis of primary aldosteronism was made in 4 patients.

CONCLUSIONS

The screening rate for primary aldosteronism is low in a CKD population, especially in patients who are older, have a lower eGFR and normal serum potassium. The consequences of undiagnosed primary aldosteronism in this select population may be substantial due to the cardiovascular and renal sequelae associated with untreated disease.

The Relationship Between Renal Stones and Primary Aldosteronism

INTRODUCTION

The association between primary aldosteronism (PA) and nephrolithiasis is still unclear. The hypercalciuria and hypocitraturia of PA patients might be the reason leading to recurrent calcium nephrolithiasis. This study aimed to evaluate the relationship between PA and renal stones, including stone size and density.

MATERIALS AND METHODS

From February 2010 to March 2021, we retrospectively collected 610 patients who presented to our medical center with hypertension history, and all these patients, suspicious of PA, had PA data survey. In total, 147 patients had kidney stone and were divided into 44 patients with essential hypertension as group 1 and 103 patients with PA as group 2. Pearson χ² test and independent Student's t-test were performed to examine the differences among variables.

RESULTS

The mean age was 54.4 ± 12.0 years in group 1 and 53.0 ± 11.1 years in group 2. The incidence rate of renal stones in the PA group was around 24%. No significant differences between the two groups were found for gender, systolic/diastolic blood pressure, duration of hypertension, diabetes mellitus history, and laterality of kidney stone; however, mean stone size was 4.0 ± 3.3 mm in group 1 and 6.5 ± 7.2 mm in group 2, with a significantly larger renal stone size noted in the PA group than that in the essential hypertension group (p = 0.004). Hounsfield unit (HU) density was higher in the PA group vis-à-vis the essential hypertension cohort, although this did not reach a significant difference (p = 0.204).

CONCLUSIONS

Our study revealed that PA patients had a higher incidence rate of renal stones compared to that of the general population. Besides, the PA-related renal stones also presented as larger and harder than those of the essential hypertension group. Further investigation concerning the association between PA and renal stones is warranted.

Circadian control of human cardiovascular function

Endogenous circadian rhythms prepare the cardiovascular (CV) system for optimal function to match the daily anticipated behavioral and environmental cycles, including variable activities when awake during the day and recuperation when sleeping at night. The overall day-night patterns in most CV variables result from the summation of predictable circadian effects with variable behavioral and environmental effects on the CV system. The circadian system has also been implicated in the morning peak in the incidence of adverse CV events, including myocardial infarction, stroke, and sudden cardiac death. We discuss the resting and stress-reactive circadian control of CV physiology in humans and suggest future research opportunities, including improving CV therapy by optimally timing therapy relative to a person's internal body clock time.

Subtype diagnosis, treatment, complications and outcomes of primary aldosteronism and future direction of research: a position statement and consensus of the Working Group on Endocrine Hypertension of the European Society of Hypertension

: Primary aldosteronism is a frequent cause of secondary hypertension requiring a specific pharmacological treatment with mineralocorticoid receptor antagonist or with unilateral adrenalectomy. These treatments have shown to reduce the excess of cardiovascular risk characteristically associated with this disease. In part I of this consensus, we discussed the procedures for the diagnosis of primary aldosteronism. In the present part II, we address the strategies for the differential diagnosis of primary aldosteronism subtypes and therapy. We also discuss the evaluation of outcomes and provide suggestions for follow-up as well as cardiovascular and metabolic complications specifically associated with primary aldosteronism. Finally, we analyse the principal gaps of knowledge and future challenges for research in this field.

Hypokalemia and the Prevalence of Primary Aldosteronism

Hypokalemia is closely linked with the pathophysiology of primary aldosteronism (PA). Although hypokalemic PA is less common than the normokalemic course of the disease, hypokalemia is of particular importance for the manifestation and development of comorbidities. Specifically, a growing body of evidence demonstrates that hypokalemia in PA patients is associated with a more severe disease course regarding cardiovascular and metabolic morbidity and mortality. It is also well appreciated that low potassium levels per se can promote or exacerbate hypertension. The spectrum of hypokalemia-related symptoms ranges from asymptomatic courses to life-threatening conditions. Hypokalemia is found in 9-37% of all cases of PA with a predominance in patients with aldosterone producing adenoma. Conversely, hypokalemia resolves in almost 100% of cases after both, specific medical or surgical treatment of the disease. However, to date, high-level evidence about the prevalence of primary aldosteronism in a hypokalemic population is missing. Epidemiological data are expected from the recently launched IPAHK+study ("Incidence of Primary Aldosteronism in Patients with Hypokalemia").

The 2020 Italian Society of Arterial Hypertension (SIIA) practical guidelines for the management of primary aldosteronism

Background and aim

Considering the amount of novel knowledge generated in the last five years, a team of experienced hypertensionlogists was assembled to furnish updated clinical practice guidelines for the management of primary aldosteronism.

Methods

To identify the most relevant studies, the authors utilized a systematic literature review in international databases by applying the PICO strategy, and then they were required to make use of only those meeting predefined quality criteria. For studies of diagnostic tests, only those that fulfilled the Standards for Reporting of Diagnostic Accuracy recommendations were considered.

Results

Each section was jointly prepared by at least two co-authors, who provided Class of Recommendation and Level of Evidence following the American Heart Association methodology. The guidelines were sponsored by the Italian Society of Arterial Hypertension and underwent two rounds of revision, eventually reexamined by an External Committee. They were presented and thoroughly discussed in two face-to-face meetings with all co-authors and then presented on occasion of the 36th Italian Society of Arterial Hypertension meeting in order to gather further feedbacks by all members. The text amended according to these feedbacks was subjected to a further peer review.

Conclusions

After this process, substantial updated information was generated, which could simplify the diagnosis of primary aldosteronism and assist practicing physicians in optimizing treatment and follow-up of patients with one of the most common curable causes of arterial hypertension.

Disease monitoring of Primary Aldosteronism

Primary aldosteronism (PA) is a highly prevalent cause of arterial hypertension featuring excess cardiovascular events. A timely diagnosis and treatment of PA cures hyperaldosteronism and can provide resolution or improvement of arterial hypertension, even when the latter is resistant to drug treatment. Accordingly, strategies to screen early and widely the hypertensive patients for PA by means of simplified diagnostic algorithms are justified. Such strategies are particularly beneficial in subgroups of hypertensive patients, who are at the highest cardiovascular risk. Broadening of screening strategies means facing with an increased number of patients where monitoring the disease becomes necessary. Hence, after identification of the surgically and non surgically curable cases of PA and implementation of targeted treatment physicians are faced with the challenges of follow-up, which are scantly discussed in the literature. Hence, the purpose of this paper is to provide some recommendations on how to optimize the monitoring of patients in whom the PA subtype has been diagnosed and treatment, either with unilateral laparoscopic adrenalectomy or medically, has been instituted.

Application of CT texture analysis to assess the localization of primary aldosteronism

We performed present study to investigate whether the localization of primary aldosteronism (PA) can be predicted using quantitative texture analysis on unenhanced computed tomography (CT). Plain CT data of 82 PA patients (54 unilateral (right-sided:left-sided = 24:30), 28 bilateral) were analyzed retrospectively. After semi-automatically setting the region of interest to include the whole adrenal gland, texture analyses were performed with or without a Laplacian of Gaussian filter with various spatial scaling factors (SSFs). Logistic regression analysis was performed using the extracted histogram-based texture features to identify parameters capable of predicting excessive aldosterone production. The result of adrenal venous sampling served as gold standard in present study. As a result, logistic regression analysis indicated that the mean gray level intensity (p = 0.026), the mean value of the positive pixels (p = 0.003) in the unfiltered image, and entropy (p = 0.027) in the filtered image (SSF: 2 mm) were significant parameters. Using the model constructed by logistic regression analysis and the optimum cutoff value, the localization of PA (three multiple choices of left, right or bilateral) was determined with an accuracy of 67.1% (55/82). CT texture analysis may provide a potential avenue for less invasive prediction of the localization of PA.

A short review of primary aldosteronism in a question and answer fashion

OBJECTIVES

The aim of this study was to present up to date information concerning the diagnosis and treatment of primary aldosteronism (PA). PA is the most common cause of endocrine hypertension. It has been reported up to 24% of selective referred hypertensive patients.

METHODS

We did a search in Pub-Med and Google Scholar using the terms: PA, hyperaldosteronism, idiopathic adrenal hyperplasia, diagnosis of PA, mineralocorticoid receptor antagonists, adrenalectomy, and surgery. We also did cross-referencing search with the above terms. We had divided our study into five sections: Introduction, Diagnosis, Genetics, Treatment, and Conclusions. We present our results in a question and answer fashion in order to make reading more interesting.

RESULTS

PA should be searched in all high-risk populations. The gold standard for diagnosis PA is the plasma aldosterone/plasma renin ratio (ARR). If this test is positive, then we proceed with one of the four confirmatory tests. If positive, then we proceed with a localizing technique like adrenal vein sampling (AVS) and CT scan. If the lesion is unilateral, after proper preoperative preparation, we proceed, in adrenalectomy. If the lesion is bilateral or the patient refuses or is not fit for surgery, we treat them with mineralocorticoid receptor antagonists, usually spironolactone.

CONCLUSIONS

Primary aldosteronism is the most common and a treatable case of secondary hypertension. Only patients with unilateral adrenal diseases are eligible for surgery, while patients with bilateral and non-surgically correctable PA are usually treated by mineralocorticoid receptor antagonist (MRA). Thus, the distinction between unilateral and bilateral aldosterone hypersecretion is crucial.

H-score of 11β-hydroxylase and aldosterone synthase in the histopathological diagnosis of adrenocortical tumors

PURPOSE

To assess the diagnostic performance of the H-score of 11β-hydroxylase (CYP11B1) and aldosterone synthase (CYP11B2) in the histopathological diagnosis of adrenocortical tumors (ACT).

METHODS

We retrospectively evaluated 199 cases of ACT, of which 85 were diagnosed as aldosterone-producing adenoma (APA), 66 as cortisol-producing adenoma (CPA), 9 as aldosterone-cortisol co-secreting adenoma, 30 as nonhyperfunctioning adenoma, and 9 as adrenocortical carcinoma (ACC). Immunohistochemical staining was performed using anti-CYP11B1 and anti-CYP11B2 monoclonal antibodies. The staining was quantified by the McCarty's H-score system. The diagnostic performance was assessed by the receiver operating characteristic curve (ROC).

RESULTS

The H-score of CYP11B1 is highest in the CPA group and lowest in the ACC group. The H-score of CYP11B2 in the APA group is significantly higher than other ACT groups. The area under ROC (AUC) of an increased H-score of CYP11B2 (>65) for the diagnosis of APA was 0.971 (95%CI 0.937-0.990). The AUC of an increased H-score of CYP11B1 (>204) for the diagnosis of CPA was 0.725 (95%CI 0.658-0.786). The AUC of a decreased H-score of CYP11B1 (<85) for the diagnosis of ACC was 0.960 (95%CI 0.923-0.983).

CONCLUSIONS

H-score of CYP11B1 and CYP11B2 are reliable tools for the histopathological subtyping of functional benign ACT and may offer some value in the histopathological diagnosis of malignant ACT.

The characteristics of captopril challenge test-positive patients using various criteria

Introduction:

The captopril challenge test (CCT) is the major confirmatory test for primary aldosteronism (PA), and frequently carried out because of its convenience. However, it presents false-negative results with a certain probability, and as there are many criteria for CCT, it is not concluded yet which criteria to use.

Materials and methods:

A total of 71 PA patients were evaluated. We compared CCT-positive and CCT-negative patients in the following three criteria: plasma aldosterone/renin ratio (ARR) >200 after the CCT (criterion 1); plasma aldosterone concentration (PAC) >120 pg/ml after the CCT (criterion 2); and PAC suppression <30% of PAC before CCT (criterion 3).

Results:

The positive rate was 70.4%, 64.8% and 54.9% for criterion 1, criterion 2 and criterion 3, respectively. With criterion 1, the baseline plasma renin activity was lower, thus baseline ARR was higher in CCT-positive patients. With criterion 2, PAC was higher and estimated sodium intake and K were lower in CCT-positive patients. With criterion 3, K and PAC were lower in CCT-positive patients. Although it was not significant, in the patients with high sodium intake, the positive rate of criterion 1 was higher than that of the other criteria.

Conclusions:

ARR>200 is the valuable criterion for the diagnosis of PA.

Serum Aldosterone Is Related to Left Ventricular Geometry and Function in Young Adults with Never-Treated Primary Hypertension

Background: Although aldosterone has been demonstrated to induce left ventricular (LV) hypertrophy not only in primary aldosteronism but also in primary hypertension (HT), it can be affected by multiple factors, including age, and the effect of aldosterone on LV function is controversial. This study was to investigate the relationship of aldosterone to changes in LV geometry and function in young adults with never-treated HT. Methods: Seventy-five consecutive patients (age, 29.8 ± 6.3 years) with never-treated HT and 45 normal controls were enrolled. Echocardiographic values and LV global longitudinal strain (LVGLS) were obtained. Serum aldosterone concentration (SAC) and serum procollagen type III amino-terminal peptide (PIIINP) level were obtained in HT patients. Results: HT patients had higher LV mass index, higher relative wall thickness (RWT), and worse LV function than normal controls. LVGLS and e’ velocity were worse in HT patients with normal geometry than in normal controls. SAC was well correlated with LV mass index, RWT, e’ velocity, LVGLS, and PIIINP (all p < 0.05). LV geometry pattern was most related to SAC among clinical parameters (p = 0.019). LVGLS was most related to LV geometry and diastolic blood pressure. In contrast, e’ velocity was most related to PIIINP. Conclusion: Our findings may indicate that in young patients with never-treated HT, aldosterone significantly contributes to changes in LV geometry and functional impairment through its pro-hypertrophic and myocardial fibrosis effects beyond blood pressure.

Diagnostic value of adrenal iodine-131 6-beta-iodomethyl-19-norcholesterol scintigraphy for primary aldosteronism: a retrospective study at a medical center in North Taiwan

BACKGROUND

Primary aldosteronism (PA) is a common cause of secondary hypertension. Among the many leading causes of PA, the two most frequent are, bilateral adrenal hyperplasia (BAH) and aldosterone-producing adenomas (APA). Since a solitary APA may be cured surgically, but BAH needs lifelong pharmacologic therapy, confirmation is mandatory before surgery. We herein sought to determine the diagnostic value of iodine-131 6-beta-iodomethyl-19-norcholesterol (NP-59) adrenal scintigraphy to distinguish BAH from APA.

PATIENTS AND METHODS

Patients clinically suspected of PA from March 2000 to October 2016 were retrospectively analyzed. A total of 145 patients, including 74 postunilateral adrenalectomy and seven postradiofrequency ablation for adrenal mass, were reviewed. All patients received NP-59 adrenal scintigraphy prior to surgery. The accuracy of the NP-59 adrenal scintigraphy was confirmed by the pathologic findings and postoperative outcomes.

RESULTS

Among 81 patients receiving interventional procedures for adrenal mass, adenoma was eventually diagnosed in 72 patients according to their pathologic results, with 60 unilaterally and seven bilaterally localized lesions by NP-59 scintigraphy; nevertheless, there were five negative findings initially. The sensitivity, specificity, and positive predictive value of NP-59 scintigraphy for APA detection were therefore 83.3, 44.4, and 92.3%, respectively. Moreover, single-photon emission computed tomography/computed tomography scan increased the sensitivity and specificity, but not the positive predictive value (85.0, 60.0, and 89.5%) of NP-59 scintigraphy in this study.

CONCLUSION

NP-59 adrenal scintigraphy is a useful imaging test to detect APA. Lateralization by this modality prior to surgical intervention may reduce the need for such invasive procedures as adrenal venous sampling.

Primary aldosteronism associated with a germline variant in CACNA1H

The CACNA1H gene encodes the pore-forming α1 subunit of the T-type voltage-dependent calcium channel Ca_V3.2, expressed abundantly in the adrenal cortex. Mutations in CACNA1H are associated with various forms of primary aldosteronism (PA), including familial hyperaldosteronism type 4 (FH4). We describe a patient with refractory hypokalaemia and elevated aldosterone secretion independent of renin activity. Despite the absence of overt hypertension in this patient, the laboratory evaluation was consistent with a diagnosis of PA. Whole-exome sequencing revealed a de novo missense variant, R890H, in the voltage sensing domain of CACNA1H Expression of the variant channel in cells resulted in decreased whole-cell current, consistent with a loss-of-function. We hypothesise this variant is the genetic cause of pathological aldosterone secretion in this patient, and thereby expand the current understanding of the genetic basis of FH4.

Separate and interacting effects of the endogenous circadian system and behaviors on plasma aldosterone in humans

Measurements of aldosterone for diagnosis of primary aldosteronism are usually made from blood sampled in the morning when aldosterone typically peaks. We tested the relative contributions and interacting influences of the circadian system, ongoing behaviors, and prior sleep to this morning peak in aldosterone. To determine circadian rhythmicity and separate effects of behaviors on aldosterone, 16 healthy participants completed a 5-day protocol in dim light while all behaviors ranging from sleep to exercise were standardized and scheduled evenly across the 24-h circadian period. In another experiment, to test the separate effects of prior nocturnal sleep or the inactivity that accompanies sleep on aldosterone, 10 healthy participants were studied across 2 nights: 1 with sleep and 1 with maintained wakefulness (randomized order). Plasma aldosterone was measured repeatedly in each experiment. Aldosterone had a significant endogenous rhythm ( P < 0.001), rising across the circadian night and peaking in the morning (~8 AM). Activity, including exercise, increased aldosterone, and different behaviors modulated aldosterone differently across the circadian cycle (circadian phase × behavior interaction; P < 0.001). In the second experiment, prior nocturnal sleep and prior rested wakefulness both increased plasma aldosterone ( P < 0.001) in the morning, to the same extent as the change in circadian phases between evening and morning. The morning increase in aldosterone is due to effects of the circadian system plus increased morning activities and not prior sleep or the inactivity accompanying sleep. These findings have implications for the time of and behaviors preceding measurement of aldosterone, especially under conditions of shift work and jet lag.

MicroRNA-21 ablation exacerbates aldosterone-mediated cardiac injury, remodeling, and dysfunction

Primary aldosteronism is characterized by excess aldosterone secretion by the adrenal gland independent of the renin-angiotensin system and accounts for ~10% of hypertensive patients. Excess aldosterone causes cardiac hypertrophy, fibrosis, inflammation, and hypertension. The molecular mechanisms that trigger the onset and progression of aldosterone-mediated cardiac injury remain incompletely understood. MicroRNAs (miRNAs) are endogenous, small, noncoding RNAs that have been implicated in multiple cardiac pathologies; however, their regulation and role in aldosterone-mediated cardiac injury and dysfunction remains mostly unknown. We previously reported that microRNA-21 (miR-21) is the most upregulated miRNA by excess aldosterone in the left ventricle in a rat experimental model of primary aldosteronism. To elucidate the role of miR-21 in aldosterone-mediated cardiac injury and dysfunction, miR-21 knockout mice and their wild-type littermates were treated with aldosterone infusion and salt in the drinking water for 2 or 8 wk. miR-21 genetic ablation exacerbated aldosterone/salt-mediated cardiac hypertrophy and cardiomyocyte cross-sectional area. Furthermore, miR-21 genetic ablation increased the cardiac expression of fibrosis and inflammation markers and fetal gene program. miR-21 genetic ablation increased aldosterone/salt-mediated cardiac dysfunction but did not affect aldosterone/salt-mediated hypertension. miR-21 target gene Sprouty 2 may be implicated in the cardiac effects of miR-21 genetic ablation. Our study shows that miR-21 genetic ablation exacerbates aldosterone/salt-mediated cardiac hypertrophy, injury, and dysfunction blood pressure independently. These results suggest that miR-21 plays a protective role in the cardiac pathology triggered by excess aldosterone. Furthermore, miR-21 supplementation may be a novel therapeutic approach to abolish or mitigate excess aldosterone-mediated cardiovascular deleterious effects in primary aldosteronism.

Primary Aldosteronism and Cerebrovascular Diseases

As diagnostic techniques have advanced, primary aldosteronism (PA) has emerged as the most common cause of secondary hypertension. The excess of aldosterone caused by PA resulted in not only cardiovascular complications, including coronary artery disease, myocardial infarction, arrhythmia, and heart failure, but also cerebrovascular complications, such as stroke and transient ischemic attack. Moreover, PA is associated more closely with these conditions than is essential hypertension. In this review, we present up-to-date findings on the association between PA and cerebrovascular diseases.

Aldosterone Mediated Regulation of Epithelial Sodium Channel (ENaC) Subunits in the Rat Hypothalamus

Current evidence suggests that the epithelial Na⁺ channel (ENaC) in the brain plays a significant role in the development of hypertension. ENaC is present in vasopressin (VP) neurons in the hypothalamus, suggesting that ENaC in VP neurons is involved in the regulation of blood pressure. Our recent study demonstrated that high dietary salt intake caused an increase in the expression and activity of ENaC that were responsible for the more depolarized basal membrane potential in VP neurons. A known regulator of ENaC expression, the mineralocorticoid receptor (MR), is present in VP neurons, suggesting that ENaC expression in VP neurons is regulated by aldosterone. In this study, the effects of aldosterone and corticosterone on ENaC were examined in acute hypothalamic slices. Real-time PCR and Western blot analysis showed that aldosterone and corticosterone treatment resulted in a significant increase in the expression of γENaC, but not α- or βENaC, and that this expression was attenuated by MR and glucocorticoid receptor (GR) antagonists. Moreover, chromatin immunoprecipitation demonstrated that the aldosterone-MR complex directly interacts with the promoter region of the γENaC gene. However, the treatment with aldosterone did not cause subcellular translocation of ENaC toward the plasma membrane nor an increase in ENaC Na⁺-leak current. These results indicate that expression of γENaC in VP neurons is induced by aldosterone and corticosterone through their MR and GR, respectively; however, aldosterone or corticosterone alone is not sufficient enough to increase ENaC current when they are applied to hypothalamic slices in vitro.

Could sodium imbalances predispose to postoperative venous thromboembolism? An analysis of the NSQIP database

Background

Hyponatremia is common among patients with pulmonary embolism, while hypernatremia increases the risk of venous thromboembolism (VTE). Our objective was to evaluate the association between sodium imbalances and the incidence of VTE and other selected perioperative outcomes.

Methods

We conducted a retrospective cohort study using the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) and identified 1,108,704 patients undergoing major surgery from 2008 to 2012. We evaluated 30-day perioperative outcomes, including mortality and cardiac, respiratory, neurological, urinary, wound, and VTE outcomes. Multivariate logistic regressions were used to estimate the odds of 30-day perioperative outcomes.

Results

Compared with the normal sodium group, in which VTE occurred in 1.0% of patients, 1.8% of patients in the hyponatremia group (unadjusted odds ratio (OR) 1.84) and 2.4% of patients in the hypernatremia group (unadjusted OR 2.49) experienced VTE. Crude mortality was 1.3% in the normal sodium group, 4.9% in the hyponatremia group (unadjusted OR 3.93) and 8.4% in the hypernatremia group (unadjusted OR 7.01). Crude composite morbidity was 7.1% for the normal sodium group, 16.7% for the hyponatremia group (unadjusted OR 2.63) and 20.6% for the hypernatremia group (unadjusted OR 3.43). After adjusting for potential confounders, hyponatremia and hypernatremia remained significantly and independently associated with an increased risk of VTE (adjusted OR 1.43 and 1.56, respectively), mortality (adjusted OR 1.39 and 1.39, respectively) and composite morbidity (adjusted OR 2.15 and 3.34, respectively).

Conclusions

Pre-operative hyponatremia and hypernatremia are potential prognostic markers for perioperative 30-day morbidity, mortality and VTE.

Role of Venous Sampling in the Diagnosis of Endocrine Disorders

Venous sampling is the gold standard for localizing abnormal hormone secretion in several endocrine disorders. The most common indication for venous sampling is in the workup of primary aldosteronism, adrenocorticotropic hormone-dependent Cushing's syndrome, and hyperparathyroidism. In experienced hands, venous sampling is safe and accurate. This review discusses the role of venous sampling in the workup of endocrine disease, describing the underlying anatomy and pathophysiology, as an understanding of these concepts is essential for technical and clinical success.

Insufficiency of the zona glomerulosa of the adrenal cortex and progressive kidney insufficiency following unilateral adrenalectomy - case report and discussion

BACKGROUND

Primary aldosteronism (PA) is the most common cause of secondary hypertension and bilateral adrenal hyperplasia (BAH) and aldosterone-producing adenoma (APA) seem to be the most common causes of PA. Unilateral adrenalectomy (UA) is the preferred treatment for APA, although the benefits are still difficult to assess.

CASE REPORT

We present a case report of a 69-year old man with a 30 year history of hypertension and probably long-standing PA due to APA, with typical organ complications. Since repeated abdominal CT scans were equivocal, not showing radiological changes characteristic for PA, the diagnosis of APA was delayed and was only finally confirmed by adrenal venous sampling which demonstrated unilateral aldosteronism. The patient underwent UA, complicated by mineralocorticoid deficiency syndrome and increased creatinine and potassium levels. At 12 months follow-up the patient still had hyperkalemia and was fludrocortisone dependent.

CONCLUSIONS

Older patients and patients with long-lasting PA who are treated with UA may demonstrate deterioration of renal function and develop transient or persistent insufficiency of the zona glomerulosa of the remaining adrenal gland necessitating fludrocortisone supplementation. Transient hyperkalemia may be observed following UA as a result of the prolonged effects of aldosterone antagonists and/or transient mineralocorticoid/glucocorticoid insufficiency. Additionally, the level of progression of chronic kidney disease after UA is difficult to predict. There likely exists a group of patients who might paradoxically have higher cardiovascular risk due to significant deterioration in kidney function not only resulting from the removal of the aldosterone induced glomerular hyperfiltration phenomenon. Identification of such a group requires further detailed investigation.

The Many Faces of Primary Aldosteronism and Cushing Syndrome: A Reflection of Adrenocortical Tumor Heterogeneity

Adrenal cortical tumors constitute a heterogeneous group of neoplasms with distinct clinical, morphological, and molecular features. Recent discoveries of specific genotype–phenotype correlations in adrenal cortical adenomas have transformed our understanding of their respective endocrine syndromes. Indeed, a proportion of patients with primary aldosteronism are now known to harbor adrenal cortical adenomas with heterogeneous molecular alterations (KCNJ5, ATP1A1, ATP2B3, and CACNA1D) involving the calcium/calmodulin kinase signaling pathway. Several lines of evidence suggest that KCNJ5-mutant aldosterone-producing adenomas have distinct clinicopathological phenotype compared to those harboring ATP1A1, ATP2B3, and CACNA1D mutations. Benign adrenal cortical tumors presenting with Cushing syndrome often have diverse mutations (PRKACA, PRKAR1A, GNAS, PDE11A, and PDE8B) involving the cyclic AMP signaling pathway. In addition to cortisol-producing adenomas, bilateral micronodular adrenocortical disease and primary bilateral macronodular adrenal hyperplasia (PBMAH) have also expanded the spectrum of benign neoplasms causing adrenal Cushing disease. The recent discovery of inactivating ARMC5 germline mutations in PBMAH has challenged the old belief that this disorder is mainly a sporadic disease. Emerging evidence suggests that PBMAH harbors multiple distinct clonal proliferations, reflecting the heterogeneous genomic landscape of this disease. Although most solitary adrenal cortical tumors are sporadic, there is an increasing recognition that inherited susceptibility syndromes may also play a role in their pathogenesis. This review highlights the molecular and morphological heterogeneity of benign adrenal cortical neoplasms, reflected in the diverse presentations of primary aldosteronism and adrenal Cushing syndrome.

Targeted treatment of primary aldosteronism - The consensus of Taiwan Society of Aldosteronism

BACKGROUND/PURPOSE

Even with the increasing recognition of primary aldosteronism (PA) as a cause of refractory hypertension and an issue of public health, the consensus of its optimal surgical or medical treatment in Taiwan has not been reached. Our objective was to develop a clinical practice guideline that is feasible for real-world management of PA patients in Taiwan.

METHODS

The Taiwan Society of Aldosteronism (TSA) Task Force recognized the above-mentioned issues and reached this Taiwan PA consensus at its inaugural meeting, in order to provide updated information of internationally acceptable standards, and also to incorporate our local disease characteristics and constraints into PA management.

RESULTS

In patients with lateralized PA, including aldosterone producing adenoma (APA), laparoscopic adrenalectomy is the 'gold standard' of treatment. Mini-laparoscopic and laparoendoscopic single-site approaches are feasible only in highly experienced surgeons. Patients with bilateral adrenal hyperplasia or those not suitable for surgery should be treated by mineralocorticoid receptor antagonists. The outcome data of PA patient management from the literature, especially from PA patients in Taiwan, are reviewed. Mental health screening is helpful in early detection and management of psychopathology among PA patients.

CONCLUSION

We hope this consensus will provide a guideline to help medical professionals to manage PA patients in Taiwan to achieve a better quality of care.

Glucocorticoid-remediable aldosteronism in a young adult with a family history of Conn's syndrome

Glucocorticoid-remediable aldosteronism is a hereditary form of primary hyperaldosteronism and the most common monogenic cause of hypertension. We present the case of a 24-year-old man with a family history of Conn's syndrome. Yet, in the index patient, classical characteristics of mineralocorticoid excess could be reversed by exogenous glucocorticoids.

The Many Faces of Primary Aldosteronism and Cushing Syndrome: A Reflection of Adrenocortical Tumor Heterogeneity

Adrenal cortical tumors constitute a heterogeneous group of neoplasms with distinct clinical, morphological, and molecular features. Recent discoveries of specific genotype-phenotype correlations in adrenal cortical adenomas have transformed our understanding of their respective endocrine syndromes. Indeed, a proportion of patients with primary aldosteronism are now known to harbor adrenal cortical adenomas with heterogeneous molecular alterations (KCNJ5, ATP1A1, ATP2B3, and CACNA1D) involving the calcium/calmodulin kinase signaling pathway. Several lines of evidence suggest that KCNJ5-mutant aldosterone-producing adenomas have distinct clinicopathological phenotype compared to those harboring ATP1A1, ATP2B3, and CACNA1D mutations. Benign adrenal cortical tumors presenting with Cushing syndrome often have diverse mutations (PRKACA, PRKAR1A, GNAS, PDE11A, and PDE8B) involving the cyclic AMP signaling pathway. In addition to cortisol-producing adenomas, bilateral micronodular adrenocortical disease and primary bilateral macronodular adrenal hyperplasia (PBMAH) have also expanded the spectrum of benign neoplasms causing adrenal Cushing disease. The recent discovery of inactivating ARMC5 germline mutations in PBMAH has challenged the old belief that this disorder is mainly a sporadic disease. Emerging evidence suggests that PBMAH harbors multiple distinct clonal proliferations, reflecting the heterogeneous genomic landscape of this disease. Although most solitary adrenal cortical tumors are sporadic, there is an increasing recognition that inherited susceptibility syndromes may also play a role in their pathogenesis. This review highlights the molecular and morphological heterogeneity of benign adrenal cortical neoplasms, reflected in the diverse presentations of primary aldosteronism and adrenal Cushing syndrome.

A step by step approach in differential diagnosing of adrenal incidentaloma (epinephroma), (with comments on the new Clinical Practice Guidelines of the European Society of Endocrinology)

Objectives. To present a step by step approach for the diagnosis of adrenal incidentaloma (AI).

Method. An extensive review of the literature was conducted, searching the Pub-Med and Google Scholar using the Mesh terms; Adrenal; Incidentaloma; Adrenal tumours; Radiology; Diagnosis. We also did a cross-referencing search of the literature. Comments on the new European guidelines are presented.

Results. The majority of the tumours are non-functioning benign adenomas. The most important radiological characteristic of an adrenal incidentaloma is the radiation attenuation coefficient. Wash out percentage and the imaging characteristics of the tumour may help in diagnosis.

Conclusion. Density less than 10 HU is in most cases characteristic of a lipid rich benign adenoma. More than 10 HU or/and history of malignancy raise the possibility for cancer. 1 mg dexamethasone test and plasma metanephrines should be done in all patients. If there is history of hypokalemia and/or resistant hypertension we test the plasma aldosterone to plasma renin ratio (ARR). Newer studies have shown that tumours even nonfunctioning and less than 4 cm may increase the metabolic risks so we may consider surgery at an earlier stage.

Predictors of hypertension urgency in primary aldosteronism patients during the first 24 hours after surgery

Study about blood pressure variation in the first 24 hours post-operation is limited in patients with adrenal aldosterone-producing adenoma. We aim to evaluate the potential predictors for postoperative hypertension urgency during the first 24 hours after laparoscopic adrenalectomy in patients with aldosterone-producing adenoma. Clinical data of 177 patients with aldosterone-producing adenoma were retrospectively collected from January 2009 to December 2015 and the potential factors that may influence postoperative blood pressure during the first 24 hours after surgery were analyzed. The factors included gender, age, body mass index, preoperative maximum systolic blood pressure, number of antihypertensive medicines, preoperative spironolactone treatment, duration of hypertension, surgical method and approach, adenoma diameter, preoperative proteinuria, estimated glomerular filtration rate, serum potassium and serum aldosterone. Univariate and multivariate regression analyses were used to evaluate the relationship between the above variables and postoperative hypertension urgency. We found that the proportion of patients with a higher systolic blood pressure ≥ 160 mmHg and ≥ 180 mmHg were significantly increased post-operation (both p < 0.001). In multivariate analysis, the maximum systolic blood pressure was an independent predictor of postoperative hypertension urgency, and the cut-off point was 157 mmHg with the sensitivity of 66% and specificity of 82%. Multivariable analysis also showed that preoperative maximum systolic blood pressure and number of antihypertensive medicines were independent risk factors for higher postoperative systolic blood pressure. This study was derived from a high volume adrenal tumor center, and these data may provide a potential tool to guide preoperative counseling.

Radiology of the adrenal incidentalomas. Review of the literature

The term "adrenal incidentaloma" is a radiological term. Adrenal incidentalomas are adrenal tumors discovered in an imaging study that has been obtained for indications exclusive to adrenal conditions (Udelsman 2001; Linos 2003; Bulow et al. 2006; Anagnostis et al. 2009). This definition excludes patients undergoing imaging testing as part of staging and work-up for cancer (Grumbach et al. 2003; Anagnostis et al. 2009). Papierska et al. (2013) have added the prerequisite that the size of a tumor must be "greater than 1cm in diameter", in order to be called incidentaloma. Although in the most cases these masses are non-hypersecreting and benign, they still represent an important clinical concern because of the risk of malignancy or hormone hyperfunction (Barzon et al. 2003). Th e adrenal tumors belong to the commonest incidental findings having been discovered (Kanagarajah et al. 2012).

Role and Regulation of MicroRNAs in Aldosterone-Mediated Cardiac Injury and Dysfunction in Male Rats

Primary aldosteronism is characterized by excess aldosterone (ALDO) secretion independent of the renin-angiotensin system and accounts for approximately 10% of hypertension cases. Excess ALDO that is inappropriate for salt intake status causes cardiac hypertrophy, inflammation, fibrosis, and hypertension. The molecular mechanisms that trigger the onset and progression of ALDO-mediated cardiac injury are poorly understood. MicroRNAs (miRNAs) are endogenous, small, noncoding RNAs that have been implicated in diverse cardiac abnormalities, yet very little is known about their regulation and role in ALDO-mediated cardiac injury. To elucidate the regulation of miRNAs in ALDO-mediated cardiac injury, we performed a time-series analysis of left ventricle (LV) miRNA expression. Uninephrectomized male Sprague-Dawley rats were treated with ALDO (0.75 µg/h) infusion and SALT (1.0% NaCl/0.3% KCl) in the drinking water for up to 8 weeks. ALDO/SALT time dependently modulated the expression of multiple miRNAs in the LV. miR-21 was the most upregulated miRNA after 2 weeks of treatment and remained elevated until the end of the study. To elucidate the role of miR-21 in ALDO/SALT-mediated cardiac injury, miR-21 was downregulated by using antagomirs in ALDO/SALT-treated rats. miR-21 downregulation exacerbated ALDO/SALT-mediated cardiac hypertrophy, expression of fibrosis marker genes, interstitial and perivascular fibrosis, OH-proline content, and cardiac dysfunction. These results suggest that ALDO/SALT-mediated cardiac miR-21 upregulation may be a compensatory mechanism that mitigates ALDO/SALT-mediated cardiac deleterious effects. We speculate that miR-21 supplementation would have beneficial effects in reverting or mitigating cardiac injury and dysfunction in patients with primary aldosteronism.

Clinical Guidelines for the Management of Adrenal Incidentaloma

An adrenal incidentaloma is an adrenal mass found in an imaging study performed for other reasons unrelated to adrenal disease and often accompanied by obesity, diabetes, or hypertension. The prevalence and incidence of adrenal incidentaloma increase with age and are also expected to rise due to the rapid development of imaging technology and frequent imaging studies. The Korean Endocrine Society is promoting an appropriate practice guideline to meet the rising incidence of adrenal incidentaloma, in cooperation with the Korean Adrenal Gland and Endocrine Hypertension Study Group. In this paper, we discuss important core issues in managing the patients with adrenal incidentaloma. After evaluating core proposition, we propose the most critical 20 recommendations from the initially organized 47 recommendations by Delphi technique.

Histopathological Classification of Cross-Sectional Image-Negative Hyperaldosteronism

Context

Approximately half of patients with primary aldosteronism (PA) have clinically evident disease according to clinical (hypertension) and/or laboratory (aldosterone and renin levels) findings but do not have nodules detectable in routine cross-sectional imaging. However, the detailed histopathologic, steroidogenic, and pathobiological features of cross-sectional image-negative PA are controversial.

Objective

To examine histopathology, steroidogenic enzyme expression, and aldosterone-driver gene somatic mutation status in cross-sectional image-negative hyperaldosteronism.

Methods

Twenty-five cross-sectional image-negative cases were retrospectively reviewed. In situ adrenal aldosterone production capacity was determined using immunohistochemistry (IHC) of steroidogenic enzymes. Aldosterone-driver gene somatic mutation status (ATP1A1, ATP2B3, CACNA1D, and KCNJ5) was determined in the CYP11B2 immunopositive areas [n = 35; micronodule, n = 32; zona glomerulosa (ZG), n = 3] using next-generation sequencing after macrodissection.

Results

Cases were classified as multiple adrenocortical micronodules (MN; n = 13) or diffuse hyperplasia (DH) of ZG (n = 12) based upon histopathological evaluation and CYP11B2 IHC. Aldosterone-driver gene somatic mutations were detected in 21 of 26 (81%) of CYP11B2-positive cortical micronodules in MN; 17 (65%) mutations were in CACNA1D, 2 (8%) in KCNJ5, and 1 each (4% each) in ATP1A1 and ATP2B. One of 6 (17%) of nodules in DH harbored somatic aldosterone-driver gene mutations (CACNA1D); however, no mutations were detected in CYP11B2-positive nonnodular DH areas.

Conclusion

Morphologic evaluation and CYP11B2 IHC enabled the classification of cross-sectional image-negative hyperaldosteronism into MN and DH. Somatic mutations driving aldosterone overproduction are common in micronodules of MN, suggesting a histological entity possibly related to aldosterone-producing cell cluster development.

Recognition and Management of Resistant Hypertension

Despite improvements in hypertension awareness and treatment, 30%-60% of hypertensive patients do not achieve BP targets and subsequently remain at risk for target organ damage. This therapeutic gap is particularly important to nephrologists, who frequently encounter treatment-resistant hypertension in patients with CKD. Data are limited on how best to treat patients with CKD and resistant hypertension, because patients with CKD have historically been excluded from hypertension treatment trials. First, we propose a consistent definition of resistant hypertension as BP levels confirmed by both in-office and out-of-office measurements that exceed appropriate targets while the patient is receiving treatment with at least three antihypertensive medications, including a diuretic, at dosages optimized to provide maximum benefit in the absence of intolerable side effects. Second, we recommend that each patient undergo a standardized, stepwise evaluation to assess adherence to dietary and lifestyle modifications and antihypertensive medications to identify and reduce barriers and discontinue use of substances that may exacerbate hypertension. Patients in whom there is high clinical suspicion should be evaluated for potential secondary causes of hypertension. Evidence-based management of resistant hypertension is discussed with special considerations of the differences in approach to patients with and without CKD, including the specific roles of diuretics and mineralocorticoid receptor antagonists and the current place of emerging therapies, such as renal denervation and baroreceptor stimulation. We endorse use of such a systematic approach to improve recognition and care for this vulnerable patient group that is at high risk for future kidney and cardiovascular events.

Adrenocortical carcinoma, an unusual cause of secondary hypertension

We present the case of a female patient aged 39 years who was admitted to our hospital due to hypertension, severe hypokalaemia and metabolic alkalosis; physical examination was remarkable for plethoric moon face, centripetal obesity and bilateral lower extremity oedema. She was admitted for intravenous potassium replacement and further assessment of hypertension and associated clinical findings. Laboratory testing showed increased levels of aldosterone, renin, cortisol, testosterone and androstenedione. An abdominal CT revealed a large mass in the right adrenal gland with hepatic involvement. The patient was started on antihypertensive medications and underwent laparoscopic surgery for mass and liver biopsy. The pathological diagnosis was adrenocortical carcinoma with liver metastasis. Hyperaldosteronism is a cause of secondary hypertension and its diagnosis is usually benign. Adrenocortical carcinoma is a rare condition and aldosterone secreting tumours are even rarer; associated hypertension usually improves after tumour resection, but with the presence of metastasis, blood pressure control is difficult.

Secondary Hypertension: Differential Diagnosis and Basic Principles of Treatment

Secondary hypertension occurs in 5-10% of cases in the patient population with primary hypertension. The most common forms of secondary hypertension are as follows: parenchymal renal disease (renoparenchymal hypertension), renal artery stenosis (renovascular hypertension), adrenal gland adenoma (primary hyperaldosteronism), a tumour of the adrenal gland marrow (pheochromocytoma) and adenoma of adrenal and pituitary glands (Cushing’s syndrome). In patients with a typical clinical picture of secondary hypertension, the appropriate diagnostic tests should be conducted based on the suspected form of secondary hypertension. Determining a diagnosis of secondary hypertension is gradual. First, the appropriate screening tests are performed. If the screening test is positive, then additional tests to confirm the forms of secondary hypertension are conducted. Once a diagnosis of the appropriate form of secondary hypertension is confirmed, tests to distinguish causes and laterality tests to determine the precise localisation of the pathological process are applied to evaluate the response to therapy. Analysing the results of endocrine diagnostic tests provides an accurate diagnosis and selection of optimal therapeutic procedures.

[Primary hyperaldosteronism due to unilateral adrenal hyperplasia with surgical resolution]

Unilateral adrenal hyperplasia is a rare cause of primary hyperaldosteronism (around a 3%) that has surgical treatment. A case of a patient with hypertension resistant to conventional therapy in treatment with 7 drugs who presented with primary hyperaldosteronism due to unilateral adrenal hyperplasia is presented. A left adrenalectomy was performed, and the patient had a good clinical response, with no need of any drug after 2 years of surgery. Unilateral adrenal hyperplasia is a different entity and it is not an asymmetric variant of the bilateral adrenal hyperplasia. In the study of patients with primary hyperaldosteronism and imaging tests with absence of adenoma is a diagnosis that must be considered before cataloguing patients with bilateral adrenal hyperplasia and start a medical treatment, because unilateral adrenal hyperplasia would have a surgical resolution.

Primary aldosteronism in patients with acute stroke: prevalence and diagnosis during initial hospitalization

Background

Hypertension is the prime risk factor for stroke, and primary aldosteronism (PA) is the most common cause of secondary hypertension. The prevalence of PA in stroke patients has never been reported. The aim of this study was to elucidate the prevalence of PA.

Methods

A total of 427 consecutive patients with acute stroke were prospectively enrolled for this study. The screening tests were performed at the initial visit and a week after admission by measuring plasma aldosterone concentration and plasma renin activity. The rapid adrenocorticotropic hormone (ACTH) test was performed as the confirmatory test when both screening tests were positive. The primary endpoint was a final diagnosis of PA.

Results

The sensitivity of the dual screening system for the diagnosis of PA was 88.2 %, and PA was finally diagnosed in 4.0 % of acute stroke patients and in 4.9 % of stroke patients with a history of hypertension. Patients with PA were less likely to be male and have diabetes, and they had higher blood pressure at the initial visit, lower potassium concentration, and more intracerebral hemorrhage. The rapid ACTH test was performed safely even in acute stroke patients.

Conclusions

The prevalence of PA is not low among acute stroke patients. Efficient screening of PA should be performed particularly for patients with risk factors.

Trial registration

UMIN-CTR; UMIN000011021. Trial registration date: June 23, 2013 (retrospectively registered).

Renovascular Hypertension: Clinical Features, Differential Diagnoses and Basic Principles of Treatment

Renovascular hypertension is caused by renal artery stenosis. Its prevalence in populations of hypertensive patients is 1-8%, and in populations of patients with resistant hypertension, it is up to 20%. The two main causes of stenosis are atherosclerosis and fibromuscular dysplasia of the renal artery. The main clinical consequences of renal artery stenosis include renovascular hypertension, ischemic nephropathy and “flash” acute pulmonary oedema. Unilateral stenosis of the renal artery causes angiotensin II-dependent hypertension, and bilateral stenosis of the renal arteries produces volume-dependent hypertension. Renovascular aetiology of hypertension should be questioned in patients with resistant hypertension, hypertension with a murmur identified upon auscultation of the renal arteries, and a noticeable side-to-side difference in kidney size. Non-invasive diagnostic tests include the determination of concentrations of peripheral vein plasma renin activity, the captopril test, captopril scintigraphy, colour Doppler ultrasonography, computed tomography angiography, and nuclear resonance angiography. Renovasography represents the gold standard for the diagnosis of renovascular hypertension. The indications for revascularization of the renal artery include haemodynamically significant renal artery stenosis (with a systolic pressure gradient at the site of stenosis of - ΔP ≥ 20 mmHg, along with the ratio of the pressure in the distal part of the renal artery (Pd) and aortic pressure (Pa) less than 0.9 (Pd/Pa < 0.9)), resistant hypertension, loss of renal function after administration of ACE inhibitors or angiotensin receptor II blockers, and recurrent flash pulmonary oedema associated with bilateral renal artery stenosis. The contraindications for renal artery revascularization include a longitudinal diameter of the affected kidney that is less than 8.0 cm, the resistance index measured from the segmental arteries peak blood flow (RI) > 0.8, chronic kidney disease (GFR <30 ml/min/1.73 m2) and negative captopril scintigraphy (lack of lateralization).

Comparison of radiofrequency ablation versus laparoscopic adrenalectomy for benign aldosterone-producing adenoma

PURPOSE

To retrospectively compare the safety and efficacy of radiofrequency ablation (RFA) with laparoscopic adrenalectomy (LA) in treating aldosterone-producing adenoma (APA) of the adrenal gland.

MATERIALS AND METHODS

From September 2009 to September 2013, seven patients, diagnosed with unilateral adrenal APA and underwent computed tomography (CT)-guided percutaneous RFA, were recruited in this retrospective study. Eighteen unilateral adrenal APA with the same tumor size (<25 mm) who underwent LA during the same interval were enrolled as control group. Treatment success was defined as complete tumor ablation on follow-up CT scan and normalization of serum aldosterone-to-renin ratio. We also compared "normalization ability" between RFA group and LA group. Normalization ability was defined as reduction in blood pressure, decrease in number of antihypertensive medicine use, reduction in serum aldosterone, and increase in serum potassium level.

RESULTS

There was no statistically significant demographic difference in both groups. The mean tumor size was 18 (8-25) mm in RFA and 19 (11-25) mm in LA groups, respectively. There was only one intra-procedure hypertensive crisis in the RFA group. No other complications needed further management in both groups. During an interval of 3-6 months of follow-up, the treatment success rate reached 100 % in the RFA group versus 94.4 % in the LA group. Normalization ability was statistically equivalent in the RFA and the LA group. Comparing with LA group, RFA group demonstrated with less post-operative pain (visual analog scale, 2.0 ± 1.16 vs. 4.22 ± 1.44, p < 0.001) and shorter operative time (105 ± 34 vs. 194 ± 58 min, p < 0.001).

CONCLUSIONS

CT-guided percutaneous RFA is effective, safe and is a justifiable alternative for patients who are reluctant or unfit for laparoscopic surgery for the treatment of APA.

Subtype prediction in primary aldosteronism: measurement of circadian variation of adrenocortical hormones and 24-h urinary aldosterone

OBJECTIVE

Currently, adrenal venous sampling (AVS) is the only reliable method to distinguish unilateral from bilateral hyperaldosteronism in primary aldosteronism (PA). However, AVS is costly and time-consuming compared with simple blood tests. In this study, we conducted a retrospective study to determine whether circadian variation in plasma adrenocortical hormone levels (i.e. aldosterone, cortisol and ACTH) and a 24-h urinary aldosterone could contribute to the clinical differentiation between unilateral hyperaldosteronism (UHA) and bilateral hyperaldosteronism (BHA).

DESIGN

In 64 patients who were diagnosed with PA and underwent AVS, 32 and 22 patients were diagnosed with UHA and BHA, respectively. Plasma adrenocortical hormone levels at 0:00, 6:00, 12:00 and 18:00 and 24-h urinary aldosterone under a condition of 6 g daily dietary sodium chloride intake were measured.

RESULTS

Baseline plasma aldosterone concentration (PAC) and 24-h urinary aldosterone level in patients with UHA were significantly higher than in patients with BHA, particularly at 6:00. The area under the ROC curve for PAC at 0:00, 6:00, 12:00 and 18:00 and 24-h urinary aldosterone to discriminate UHA and BHA was 0·839 [95% confidence interval (CI); 0·73-0·95], 0·922 (95% CI; 0·85-1·00), 0·875 (95% CI; 0·78-0·97), 0·811 (95% CI; 0·69-0·93), 0·898 (95% CI; 0·81-0·99), respectively.

CONCLUSIONS

PAC at different blood sampling times and 24-h urinary aldosterone level may be diagnostically helpful in discriminating between UHA and BHA. We believe that these tests could reduce the number of unnecessary AVS procedures.

The Management of Primary Aldosteronism: Case Detection, Diagnosis, and Treatment: An Endocrine Society Clinical Practice Guideline

OBJECTIVE

To develop clinical practice guidelines for the management of patients with primary aldosteronism.

PARTICIPANTS

The Task Force included a chair, selected by the Clinical Guidelines Subcommittee of the Endocrine Society, six additional experts, a methodologist, and a medical writer. The guideline was cosponsored by American Heart Association, American Association of Endocrine Surgeons, European Society of Endocrinology, European Society of Hypertension, International Association of Endocrine Surgeons, International Society of Endocrinology, International Society of Hypertension, Japan Endocrine Society, and The Japanese Society of Hypertension. The Task Force received no corporate funding or remuneration.

EVIDENCE

We searched for systematic reviews and primary studies to formulate the key treatment and prevention recommendations. We used the Grading of Recommendations, Assessment, Development, and Evaluation group criteria to describe both the quality of evidence and the strength of recommendations. We used "recommend" for strong recommendations and "suggest" for weak recommendations.

CONSENSUS PROCESS

We achieved consensus by collecting the best available evidence and conducting one group meeting, several conference calls, and multiple e-mail communications. With the help of a medical writer, the Endocrine Society's Clinical Guidelines Subcommittee, Clinical Affairs Core Committee, and Council successfully reviewed the drafts prepared by the Task Force. We placed the version approved by the Clinical Guidelines Subcommittee and Clinical Affairs Core Committee on the Endocrine Society's website for comments by members. At each stage of review, the Task Force received written comments and incorporated necessary changes.

CONCLUSIONS

For high-risk groups of hypertensive patients and those with hypokalemia, we recommend case detection of primary aldosteronism by determining the aldosterone-renin ratio under standard conditions and recommend that a commonly used confirmatory test should confirm/exclude the condition. We recommend that all patients with primary aldosteronism undergo adrenal computed tomography as the initial study in subtype testing and to exclude adrenocortical carcinoma. We recommend that an experienced radiologist should establish/exclude unilateral primary aldosteronism using bilateral adrenal venous sampling, and if confirmed, this should optimally be treated by laparoscopic adrenalectomy. We recommend that patients with bilateral adrenal hyperplasia or those unsuitable for surgery should be treated primarily with a mineralocorticoid receptor antagonist.

Hyperaldosteronism after decreased renal K+ excretion in KCNMB2 knockout mice

The kidney is the primary organ ensuring K(+) homeostasis. K(+) is secreted into the urine in the distal tubule by two mechanisms: by the renal outer medullary K(+) channel (Kir1.1) and by the Ca(2+)-activated K(+) channel (KCa1.1). Here, we report a novel knockout mouse of the β2-subunit of the KCa1.1 channel (KCNMB2), which displays hyperaldosteronism after decreased renal K(+) excretion. KCNMB2(-/-) mice displayed hyperaldosteronism, normal plasma K(+) concentration, and produced dilute urine with decreased K(+) concentration. The normokalemia indicated that hyperaldosteronism did not result from primary aldosteronism. Activation of the renin-angiotensin-aldosterone system was also ruled out as renal renin mRNA expression was reduced in KCNMB2(-/-) mice. Renal K(+) excretion rates were similar in the two genotypes; however, KCNMB2(-/-) mice required elevated plasma aldosterone to achieve K(+) balance. Blockade of the mineralocorticoid receptor with eplerenone triggered mild hyperkalemia and unmasked reduced renal K(+) excretion in KCNMB2(-/-) mice. Knockout mice for the α-subunit of the KCa1.1 channel (KCNMA1(-/-) mice) have hyperaldosteronism, are hypertensive, and lack flow-induced K(+) secretion. KCNMB2(-/-) mice share the phenotypic traits of normokalemia and hyperaldosteronism with KCNMA1(-/-) mice but were normotensive and displayed intact flow-induced K(+) secretion. Despite elevated plasma aldosterone, KNCMB2(-/-) mice did not display salt-sensitive hypertension and were able to decrease plasma aldosterone on a high-Na(+) diet, although plasma aldosterone remained elevated in KCNMB2(-/-) mice. In summary, KCNMB2(-/-) mice have a reduced ability to excrete K(+) into the urine but achieve K(+) balance through an aldosterone-mediated, β2-independent mechanism. The phenotype of KCNMB2 mice was similar but milder than the phenotype of KCNMA1(-/-) mice.

A curious case of paralysis

Primary hyperaldosteronism is found in up to 13% of patients with hypertension. This article describes a patient with hypokalemia, hypertension, and periodic paralysis that were caused by primary hyperaldosteronism. Plasma aldosterone concentration to plasma renin activity ratio is a common screening test, and adrenal vein sampling can be performed to determine which gland is overproducing aldosterone. Treatment with mineralocorticoid receptor antagonists or adrenalectomy gives similar reductions in BP.