Novel metabolomic profile of subjects with non-classic apparent mineralocorticoid excess.

Nonclassic apparent mineralocorticoid excess (NC-AME) is proposed as a novel clinical condition with a mild phenotypic spectrum that ranges from normotension to severe hypertension. This condition is mainly characterized by a high serum cortisol to cortisone ratio (F/E) and concomitant low cortisone (E), however further metabolic changes in NC-AME have not been studied. A cross-sectional study was performed in a primary-care cohort of 396 Chilean subjects, which were classified in two groups: NC-AME (n = 28) and healthy controls (n = 27). A discovery study based in untargeted metabolomics assay in serum samples from both groups was performed by UPLC-Q-TOF/MS. Global metabolomic variations were assayed by principal component analysis and further compared by orthogonal partial least-squares discriminant analysis (OPLS-DA). NC-AME subjects exhibited higher values of blood pressure, fractional excretion of potassium, and lower plasma renin activity and urinary sodium to potassium ratio. Metabolomic analyses showed 36 differentially regulated metabolites between NC-AME and control subjects. A ROC curve analyses identified eight metabolites with high discriminatory capacity between NC-AME and control subjects. Moreover, gamma-L-glutamyl-L-methionine sulfoxide and 5-sulfoxymethylfurfural, exhibited significant association with cortisone, which are potential biomarkers of NC-AME, however further assays should elucidate its biological role in setup and progression of this phenotype.

Serum concentration of mineralocorticoids, glucocorticoids, and sex steroids in peripartum bitches.

The aim of the work was to describe the profile of steroid hormones in the peripartum period of the bitch. Twenty-five healthy pregnant bitches presented for pregnancy monitoring and parturition assistance were included in the study. A blood sample was collected for routine progesterone assay, and serum was stored at -20°C. The day of parturition and the number of delivered puppies were registered. Concentrations of corticosteroids, androgens, progestogens, estrogens, for a total number of 17 different hormones, were measured using ultra-performance supercritical fluid chromatography-tandem mass spectrometry. Data were analyzed using a repeated measure, mixed-model approach, taking into account day (from day -4 to day +2 from parturition), age, parity (primiparous vs pluriparous), number of delivered puppies (<4 vs 4-8 vs > 8), and interactions between factors. Day related to parturition significantly affected the concentration of progesterone (P < 0.001), testosterone (P < 0.001), 17α-hydroxyprogesterone (P = 0.0002), and cortisone (P = 0.006). Estrogen concentration did not show any significant variation over time. Testosterone and androstenedione showed an abrupt decline on the day of parturition. The concentration of all glucocorticoids increased the day before parturition. Age or parity was not significantly associated with any of the steroids. Litter size significantly affected concentrations of aldosterone (P = 0.02) and etiocholanolone (P = 0.01). Aldosterone concentrations were higher in litters with 4 to 8 pups than in litters with more than 8 pups (P = 0.02). None of the steroids measured in our study, with the already known exception of progesterone, shows potential to be clinically useful in predicting the onset of parturition in the bitch.

Mineralocorticoid Dysfunction during Critical Illness: A Review of the Evidence.

The recent demonstration of the significant reduction in mortality in patients with septic shock treated with adjunctive glucocorticoids combined with fludrocortisone and the effectiveness of angiotensin II in treating vasodilatory shock have renewed interest in the role of the mineralocorticoid axis in critical illness. Glucocorticoids have variable interactions at the mineralocorticoid receptor. Similarly, mineralocorticoid receptor-aldosterone interactions differ from mineralocorticoid receptor-glucocorticoid interactions and predicate receptor-ligand interactions that differ with respect to cellular effects. Hyperreninemic hypoaldosteronism or selective hypoaldosteronism, an impaired adrenal response to increasing renin levels, occurs in a subgroup of hemodynamically unstable critically ill patients. The suggestion is that there is a defect at the level of the adrenal zona glomerulosa associated with a high mortality rate that may represent an adaptive response aimed at increasing cortisol levels. Furthermore, cross-talk exists between angiotensin II and aldosterone, which needs to be considered when employing therapeutic strategies.

Mineralocorticoids, glucose homeostasis and type 2 diabetes mellitus: The Henan Rural Cohort study.

AIMS: We aimed to evaluate the associations of mineralocorticoids with type 2 diabetes mellitus (T2DM) and glucose homeostasis among rural Chinese adults. METHODS: A total of 2713 participants were selected from the Henan Rural Cohort study. Serum mineralocorticoids were measured by liquid chromatography-tandem mass spectrometry. Logistic regression and restricted cubic splines were employed to evaluate the associations of mineralocorticoids with pre-diabetes and T2DM. Linear regression was implemented to assess the associations of aldosterone and 11-deoxycorticosterone with different markers of glucose homeostasis by different diabetes status. RESULTS: Elevated aldosterone and 11-deoxycorticosterone were associated with an increased prevalence of pre-diabetes and T2DM (P < 0.05), with a nonlinear dose-response trend, but the association between 11-deoxycorticosterone and T2DM was no statistical significance after adjustment. A 100% increase in ln-aldosterone was associated with a 0.029 mg/dl higher fasting plasma glucose (FPG) and a 1.2% higher HOMA2-IR among those with normal glucose tolerance (NGT), and related to a 0.034 mg/dl lower FPG, a 1.1% higher HbA1c and a 1.3% higher HOMA2-ß among individuals with pre-diabetes. A 100% increment in ln-11-deoxycorticosterone was associated with a 16% increase in HbA1c and a 5.6% decrease in HOMA2-ß in participants with T2DM. CONCLUSIONS: Higher aldosterone and 11-deoxycorticosterone are associated with T2DM risk and glucose homeostasis disorder among different diabetes status.

Selective LC-MRM/SIM-MS based profiling of adrenal steroids reveals metabolic signatures of 17α-hydroxylase deficiency.

Adrenal steroids are generated in the adrenal cortex and metabolized by various enzymes such as hydroxylases, dehydrogenases, and reductases. Determining the comprehensive metabolic signatures of adrenal steroids can provide insight into their metabolic functions and roles in the pathophysiology of adrenal diseases, including Cushing's syndrome (CS) and congenital adrenal hyperplasia (CAH). To this end, we developed an advanced quantitative profiling method of serum adrenal steroids with liquid chromatography-mass spectrometry (LC-MS) under molecular-specific scan modes. Twenty-seven steroids were separated on a 1.9-µm particle C18 column (50 × 2.1 mm) at a flow rate of 250 µL/min and quantified via triple-quadrupole MS with electrospray ionization. During validation, linearities ( r2) were higher than 0.940 with a limit of quantification of 0.1-5.0 ng/mL, and precision (coefficient of variation) and accuracy (%bias) of 3.7-14.3 % and 96.3-113.1 %, respectively. In contrast with the significantly increased serum levels of mineralocorticoids (P <  0.001), the present LC-MS assay revealed remarkably decreased levels of all glucocorticoids and androgens in a patient diagnosed with 17α-hydroxylase deficiency CAH (P <  0.001) compared to those of age- and sex-matched healthy and CS subjects. In the CAH patient, the metabolic ratios for 17α-hydroxylase were significantly decreased, whereas there was no reduction in the metabolic ratio of 17-hydroxyprogesterone to androstenedione, indicating 17,20-lyase activity. In particular, both pregnenolone and dehydroepiandrosterone sulfates, and their metabolic ratio, were identified as potential biomarkers for 17α-hydroxylase deficiency (all P <  0.001), which were also distinct from those of CS patients. The devised LC-MS assay clearly revealed the metabolic signatures of 17α-hydroxylase deficiency, as a rare phenotype of CAH, compared to both healthy and CS subjects, indicating its utility for screening adrenal diseases.

Blockade of mineralocorticoid receptor ameliorates oral contraceptive-induced insulin resistance by suppressing elevated uric acid and glycogen synthase kinase-3 instead of circulating mineralocorticoid.

Context: Estrogen-progestin combined oral contraceptive (COC) has been connected to mineralocorticoid receptor (MR) activation and adverse cardiometabolic events. We consequently hypothesised that insulin resistance (IR), hyperuricemia, and elevated circulating GSK-3 induced by COC is through activation of MR via mineralocorticoid and glucocorticoid pathways.Methods: Female Wistar rats aged 12 weeks received (po) vehicle and COC (1.0 µg ethinylestradiol plus 5.0 µg levonorgestrel) with or without MR blocker (0.25 mg/kg spironolactone; Spl), daily for eight weeks.Results: Data showed that COC treatment led to increased IR, 1-hour postload glucose level, insulinemia, triglyceride/HDL-cholesterol ratio, total cholesterol/HDL-cholesterol ratio, uric acid, GSK-3, aldosterone, corticosterone values, impaired glucose tolerance and pancreatic ß-cell function. However, MR blockade by Spl ameliorated all these alterations except that of aldosterone.Conclusion: The results demonstrate that COC induces IR, hyperuricemia and high GSK-3 levels through activation of MR via glucocorticoid dependent pathway.

Influence of hormones on the immunotolerogenic molecule HLA-G: a cross-sectional study in patients with congenital adrenal hyperplasia.

BACKGROUND: HLA-G is an immune checkpoint molecule, naturally expressed during pregnancy, playing a critical role in the tolerance of the fetal semi-allograft from the maternal immune system. While HLA-G expression levels are associated with progesterone, the influence of other hormones is still unclear. Congenital adrenal hyperplasia (CAH) represents an adequate model to study the hormonal influence on biomarkers as it leads to impaired cortisol biosynthesis and increased progesterone and androgens production due to 21-hydroxylase enzyme deficiency. METHODS: In a cross-sectional study of CAH patients matched on sex and age with healthy control, the association between circulating levels of soluble HLA-G and hormones was assessed by use of non-parametric analyses tests. Multivariable linear regressions were performed on normalized data. RESULTS: Overall, 83 CAH patients and 69 healthy controls were included. Among CAH patients, all were under glucocorticoid and 52 (62.6%) were under mineralocorticoid supplementation. Compared to controls, CAH patients had increased HLA-G levels (15 vs 8 ng/mL, P = 0.02). In controls, HLA-G level was independently associated with progesterone and estradiol (ß = 0.44 (0.35-1.27) and -0.44 (-0.94, -0.26) respectively, both P values = 0.001). In CAH patients, HLA-G level was independently associated with mineralocorticoid supplementation dosage (ß = 0.25 (0.04-0.41), P = 0.001) and estradiol (ß = -0.22 (-0.57, -0.02), P < 0.001). CONCLUSION: CAH patients had higher HLA-G levels than healthy controls. HLA-G level was positively associated with progesterone and corticosteroid supplementation, and negatively with estradiol. The association between mineralocorticoid, renin and HLA-G levels may suggest a role of the renin-angiotensin system in the expression of soluble HLA-G.

Multi-disciplinary evaluation of a 5-month-old with hypertrophic cardiomyopathy related to a functional adrenocortical tumor.

Background Hypertrophic cardiomyopathy (HCM) in childhood is a rare diagnosis, and associations with adrenocortical tumors (ACTs) have been rarely reported in the pediatric literature. Case presentation We present a case of a 5-month-old who presented with HCM and during the evaluation for hypertension was found to have elevated glucocorticoids, mineralocorticoids, androgens and urine metanephrines. During preoperative evaluation, he developed shock followed by cardiogenic collapse requiring extracorporeal membrane oxygenation (ECMO); however, he did not survive. Pathology revealed an ACT with hormone production that contributed to his demise. Conclusions Adrenocortical tumors associated with hypertrophic cardiomyopathy can be life-threatening. We discuss the complex interplay of unrestricted cortical hormone production in the setting of hypertrophic cardiomyopathy that may lead to rapid decline and poor clinical outcomes.

Oral hormonal therapy with ethinylestradiol-levonorgestrel improves insulin resistance, obesity, and glycogen synthase kinase-3 independent of circulating mineralocorticoid in estrogen-deficient rats.

Estrogen deficiency has been associated with increased incidence of cardiovascular diseases , and recent clinical trials of standard formulations of hormonal therapies have not demonstrated consistent beneficial effects. Estrogen-progestin therapy has been used as exogenous estrogen to normalize depressed estrogen level during menopause. Ovariectomized rodents mimic an estrogen-deficient state in that they develop cardiometabolic dysfunction, including insulin resistance (IR). We therefore hypothesized that hormonal therapy with combined oral contraceptive steroids, ethinylestradiol-levonorgestrel (EEL), improves IR, obesity, and glycogen synthase kinase-3 (GSK-3) through reduction of circulating mineralocorticoid in ovariectomized rats. Twelve-week-old female Wistar rats were divided into 4 groups: sham-operated (SHM) and ovariectomized (OVX) rats were treated with or without EEL (1.0 µg ethinylestradiol and 5.0 µg levonorgestrel) daily for 8 weeks. Results showed that OVX or SHM + EEL treated rats had increased HOMA-IR (homeostatic model assessment of IR), 1 h postload glucose, HOMA-ß, triglycerides (TG), total cholesterol (TC), TC/HDL cholesterol, TG/HDL cholesterol, plasma insulin, GSK-3, corticosterone, and aldosterone. On the other hand, OVX + EEL treatment ameliorated all these effects except that of aldosterone. Taken together, the results demonstrate that oral hormonal replacement with EEL improves IR and pancreatic ß-cell function and suppresses GSK-3 and glucocorticoid independent of circulating aldosterone, suggesting a positive cardiometabolic effect of oral EEL therapy in estrogen-deficient rats.

Primary Adrenal Insufficiency: Managing Mineralocorticoid Replacement Therapy.

Context: Mineralocorticoid (MC) replacement therapy in patients with primary adrenal insufficiency (PAI) was introduced more than 60 years ago. Still, there are limited data on how MC substitution should be optimized, because MC dosing regimens have only been systematically investigated in a few studies. We review the management of current standard MC replacement therapy in PAI and its plausible impact on outcome. Design: Using PubMed, we conducted a systematic review of the literature from 1939 to 2017, with the following keywords: adrenal insufficiency, MC deficiency, aldosterone, cardiovascular disease, hypertension, and heart failure. Results: The current standard treatment consists of fludrocortisone (FC) given once daily in the morning, aiming at normotension, normokalemia, and plasma renin activity in the upper normal range. Available data suggest that patients with PAI may be underreplaced with FC as symptoms and signs indicating chronic MC underreplacement, such as salt craving and postural dizziness persist, in many treated patients with PAI. Data acquired from large registry-based studies show that glucocorticoid doses for replacement in PAI are higher than those estimated from endogenous production. Glucocorticoid overreplacement may reduce the need of MC replacement but may also be a consequence of inadequate MC replacement. Conclusions: The commonly used MC replacement in PAI may not be adequate in some patients. Insufficient MC substitution may be responsible for poor cardiometabolic outcome and the failure to restore well-being adequately in patients with PAI. Well-designed studies oriented at optimizing MC replacement therapy are urgently needed.

The relation of the serum aldosterone level and central serous chorioretinopathy - a pilot study.

OBJECTIVE: The aim of this study was to investigate the serum aldosterone level and abnormal levels of mineral corticoid in patients with the central serous chorioretinopathy (CSC). PATIENTS AND METHODS: All recruited patients with CSC received fundus fluorescein angiography (FFA), enhanced depth imaging spectral-domain optical coherence tomography (EDI-OCT) and serum aldosterone assay. The patients were classified into spontaneously resolved group and unresolved group according to a 3-months follow-up of Optical Coherence Tomography (OCT) examination. Patients from unresolved group were recruited to receive treatment with 40 mg spironolactone orally for 2 months. After the treatment, the EDI-OCT and best corrected visual acuity (BCVA) were performed again to assess the treatment efficacy. RESULTS: The study included 61 patients (72 eyes) with 34 patients in the unresolved group and 27 patients in the resolved group. The aldosterone level was significantly associated with the subfoveal choroidal thickness (SFCT) of revolved CSC eyes (r=0.342, p<0.05) as well as the SFCT of unresolved CSC eyes (r=0.348, p<0.05). And the aldosterone level in the unresolved CSC group was greater than that in the spontaneously resolved group (161.8 ± 50.1 ng/dl vs. 122.5 ± 50.5 ng/dl, p<0.05). The central macular thickness and SFCT were decreased significantly (p<0.05) after the treatment with 40 mg/d spironolactone for two months. CONCLUSIONS: The unresolved CSC patients were characterized by high level of aldosterone and thickened SFCT. Spironolactone treatment was associated with the improvement of chronic CSC. Besides, the side effect of spironolactone treatment was rare.

Multiplexed steroid profiling of gluco- and mineralocorticoids pathways using a liquid chromatography tandem mass spectrometry method.

Serum steroid assays are major tools in the clinical evaluation of adrenal disorders. The main adrenal steroids are routinely measured with immunoassays. However, chromatographic methods are known to offer better specificity. We report a liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay for simultaneous quantification of 15 adrenal steroids targeting the mineralo- and gluco-corticosteroid pathways. Serum steroids combined with deuterated internal standards were extracted using successive protein precipitation and solid phase extraction steps. Cortisol, cortisone, 11-deoxycortisol, 17-hydroxyprogesterone, 21-deoxycortisol, progesterone, 11-deoxycorticosterone, corticosterone, 11-dehydrocorticosterone, 18-hydroxycorticosterone, 18-hydroxy-11-deoxycorticosterone, aldosterone, dehydroepiandrosterone sulfate, testosterone and androstenedione were resolved in fourteen minutes using a BEH C18 column coupled to a methanol-ammonium formate gradient. Detection was performed using multiple reaction monitoring quantitation. Routinely determined steroid levels by immunoassays were compared to those measured by LC-MS/MS. This method was applied to assess steroid profiles in congenital adrenal hyperplasia (CAH) patients with 21-hydroxylase deficiency. Low quantification limits depending on each steroid (ranging from 0.015ng/mL for aldosterone to 20ng/mL for DHEAS) are adapted to the clinical use. Recoveries of steroids range from 64% for 21-deoxycortisol to 101% for cortisol and are fully corrected by internal standards. A good linearity with R>0.989 is obtained for each compound. The inter-day variation coefficients ranged from 4.7% for cortisol to 16.3% for 11-deoxycorticosterone. The immunoassay for cortisol (Immulite 2000, Siemens) showed acceptable agreement with LC-MS/MS (bias +7.2%). However, Bland-Altman plots revealed large negative bias for aldosterone (-33.4%, AldoCT, CisBio international), for 17-hydroxyprogesterone at concentrations below 2ng/mL (-74.1%, OHP-CT MP Biomedical), for androstenedione (-80.3%, RIA D4, Beckman Coulter) and for 11-deoxycortisol (-125.3%, Diasource Immunoassays). Finally, the analysis of samples from 21-hydroxylase defective patients demonstrated the potential usefulness of multiplexed steroid profiling for the diagnosis and/or monitoring of different forms of congenital adrenal hyperplasia. This LC-MS/MS method provides highly sensitive and specific assessments of mineralo- and glucocorticoids pathways from a small volume sample and is therefore a promising potent tool for clinical and experimental endocrine studies.

Increased Steroid Excretion in Children with Extremely Low Birth Weight at a Median Age of 9.8 years.

BACKGROUND: Events during foetal or early extrauterine life may affect bodily structure and/or functions and even pave the way for adult diseases. AIMS: To find whether extremely low birth weight (ELBW) infants differ from healthy controls regarding the excretion of steroid metabolites. METHODS: The study compared 17 female and 10 male ELBW infants, all prepubertal, aged 8-11 years, birth weight <1,000 g, with 27 age- and sex-matched controls. All were healthy at the time of the study. Height, weight and BMI did not differ between the groups. Results were adjusted according to body surface area. 36 urinary steroid metabolites were quantified by gas chromatography-mass spectrometry. RESULTS: In the ELBW girls 33/36 steroid metabolites were higher (19 significantly) than in the controls. All 36 steroid metabolites were higher in the ELBW boys (9 significantly) than in the controls. Sums of mineralocorticoid precursors, metabolites descriptive for cortisol and parameters of adrenal androgen production were significantly higher in ELBW infants (both sexes). Only the sum of the metabolites known to be illustrative for adrenal 11ß-hydroxysteroid dehydrogenase activity was not different. CONCLUSION: Prepubertal ELBW children have an augmented urinary excretion of adrenal androgens, cortisol and mineralocorticoid precursors. These findings corroborate and help to explain the link between early-life adversity and subsequent adrenocortical function.

[Adrenal incidentalomas]. / Incidentalomes de la glande surrénale : ne pas méconnaître les tumeurs à risque.

Adrenal incidentalomas are found in approximately 2-3% of abdominal CT-scan examinations. A key issue is to determine whether the incidentaloma is neoplastic or responsible for endocrine hypersecretion, two situations in which surgical excision is recommended. Candidate incidentalomas for surgery include hypersecreting tumors (pheochromocytomas, Cushing's adenoma, Conn's adenoma) and adrenocortical carcinomas. The majority of adrenal incidentalomas are non-secreting cortical adenomas and lesions to remove account for less than 5% of adrenal incidentalomes. The pathological consequences of "subclinical" cortisol-secreting adenomas responsible for mild hypercortisolism and whether or not these tumors should be removed remain debatable.

Long-term re-evaluation of primary aldosteronism after medical treatment reveals high proportion of normal mineralocorticoid secretion.

OBJECTIVE: In most cases of primary aldosteronism (PA), An adrenal aldosterone-secreting tumor cannot be reasonably proven, so these patients undergo medical treatment. Controversial data exist about the evolution of PA after medical therapy: long-term treatment with mineralocorticoid antagonists has been reported to normalize aldosterone levels but other authors failed to find remission of mineralocorticoid hypersecretion. Thus, we planned to retest aldosterone secretion in patients with medically treated PA diagnosed at least 3 years before. DESIGN: Retrospective, cross-sectional study. METHODS: The same workup for PA as at diagnosis (basal aldosterone to renin activity ratio (ARR) and aldosterone suppression test) was performed after stopping interfering drugs and low-salt diet, in 34 subjects with PA diagnosed between 3 and 15 years earlier, by case finding from subgroups of hypertensive patients at high risk for PA. Criteria for persistence of PA were the same as at diagnosis (ARR (pg/ml per ng per ml per h) >400, aldosterone >150 pg/ml basally, and >100 pg/ml after saline infusion) or less restrictive. RESULTS: PA was not confirmed in 26 (76%) of the patients and also not in 20 (59%) using the least restrictive criteria suggested by international guidelines. Unconfirmed PA was positively associated with female sex, higher potassium levels, longer duration of hypertension, and follow-up, but not with adrenal mass, aldosterone levels at diagnosis, and treatment with mineralocorticoid antagonists. CONCLUSIONS: This study suggests that mineralocorticoid hyperfunction in patients with PA after medical treatment may decline spontaneously. Higher potassium concentration and duration of treatment seem to increase the probability of this event.

Overview of endocrine systems in primary hypertension.

Multiple hormonal factors play a major role in the functional and structural abnormalities of hypertension (HT). At present, the kidneys and, in particular, renal Na(+) retention are thought to constitute a primary and sustaining mechanism in the development of HT. However, the precise renal and hormonal mechanisms leading to increased Na(+) reabsorption and HT remain unknown. Because the vast majority of HT is primary, this article focuses on the major endocrine systems, the RAS, aldosterone, and the SNS, that play a prominent role in the pathogenesis of HT.

Inherited forms of mineralocorticoid hypertension.

PURPOSE OF REVIEW: Inherited forms of mineralocorticoid hypertension are a group of monogenic disorders that, although rare, have enlightened our understanding of normal physiology, and subsequent processes implicated in the pathogenesis of 'essential' hypertension. They often present in early life and can be a cause of major morbidity and mortality that can be effectively treated with simple but targeted pharmacological therapy. Interestingly, all the conditions centre on the regulation of sodium transport through its epithelial channel, either directly or through mediators that act via the mineralocorticoid receptor. RECENT FINDINGS: In recent years, molecular mechanisms of these conditions and their functional consequences have been elucidated. Diagnosis has been facilitated by plasma and urinary biomarkers. SUMMARY: We provide an overview and diagnostic approach to apparent mineralocorticoid excess, glucocorticoid remediable aldosteronism, familial hyperaldosteronism type 2, Liddle's syndrome, Gordon's syndrome, activating mutations of the mineralocorticoid receptor, generalized glucocorticoid resistance and hypertensive forms of congenital adrenal hyperplasia.

Indicators of mineralocorticoid excess in the evaluation of primary aldosteronism.

It is suggested to use the aldosterone-to-renin ratio (ARR) as a first test in the screening for primary aldosteronism (PA). However, many groups rather rely on the determination of urinary tetrahydroaldosterone secretion; others calculate a ratio of urinary aldosterone to plasma renin activity. The aim of the present study was to evaluate the usefulness of different parameters of aldosterone excess in the case finding of PA. The study included 28 patients with PA and 33 subjects with essential hypertension. Clinical data, which included the hormonal parameters, serum aldosterone, plasma renin concentration, urinary free aldosterone and metabolites and serum and urinary electrolyte levels were analyzed. These indices of aldosterone excess, the ARR, serum sodium to urinary sodium to (serum potassium)(2) to urinary potassium (SUSPPUP) ratio and combinations of these parameters were compared between the groups. Receiver-operating curve analysis revealed that the ARR multiplied by the SUSPPUP ratio (ARR x SUSPPUP) is the most reliable screening test, with a sensitivity of 92.3% and a specificity of 93.9% (cutoff point 199.2 (mmol l(-1))(-1)). The combination of ARR x SUSPPUP ratio with urinary free aldosterone divided by the plasma renin concentration rendered a specificity of 100%. Less useful was the correction of urinary free aldosterone and its metabolites for sodium excretion. Although the ARR and urinary free aldosterone divided by renin are good tests in the screening for PA, the combination of ARR with SUSPPUP ratio is a better indicator of an aldosterone excess and aldosterone action in patients with ongoing antihypertensive medication. Antihypertensive drugs only marginally interfere with the SUSPPUP ratio, but they may influence the ARR, whereby the effects in PA patients seem to be negligible.