Objective: Aldosterone-producing adenomas (APA) are a major cause of primary aldosteronism. Somatic mutations explain the excess aldosterone production in the majority of patients with APA with mutations in KCNJ5 encoding a potassium channel the most prevalent in most reported populations. Mechanisms driving cell proliferation are largely undefined. Design and method: Quantitative transcriptome analysis using RNA-seq was used to identify differentially expressed genes between macro-APAs (n = 9, diameter >= 30 mm) and micro-APAs (n = 12, diameter <= 10 mm). Validation of RNA-seq data by TaqMan real-time PCR was performed for 14 genes in a broader cohort of APAs (NMD, no mutation detected, n = 28; KCNJ5-mutated, n = 43). Results: Hierarchical cluster analysis of the 500 genes with largest coefficient of variation indicated sample clustering based on genotype (KCNJ5 or NMD) and APA diameter. Differential expression of 155 and 348 genes was found between micro- and macro-APAs with KCNJ5 mutations and NMD, respectively. Among the top 5 overrepresented Gene Ontology terms (biological process), cell death was exclusively enriched in NMD micro- vs NMD macro-APAs. The expression levels of 10 genes were validated with a potential function related to cell growth. Expression of BEX1 (a reported tumour suppressor) was 2.8-fold down regulated in macro-APAs relative to micro-APAs (P < 0.001), and a linear negative correlation of BEX1 expression with APA diameter was observed in NMD APAs (r = -0.501, P = 0.007). Genes involved in beta-catenin signalling, SFRP2, DKK1 and TSPAN12 were 5.9-fold (P < 0.001), 1.8-fold (P = 0.007) and 8.3-fold (P < 0.0001) down regulated, respectively, in macro-APAs compared with micro-APAs. BAI1 and CCL21 were also down regulated in macro-APAs relative to micro-APAs (3.3-fold, P = 0.026; 2.6-fold, P = 0.145, respectively). Additionally, the expression of TMPRSS3 (r = 0.727, P < 0.001), BMP4 (r = 0.389, P = 0.041) and FBXL21 (r = 0.761, P < 0.001) showed a linear positive correlation with adenoma diameter in NMD subgroup. Conclusions: APA display distinct transcriptome profiles according to adenoma diameter which may help identify genes involved in APA tumour cell growth.
Current guidelines recommend screening for PA in patients with hypertension on the basis of individual factors, that considered together are present in more than 50% of patients. Recently, some experts proposed to further expand the screening for PA to all patients with hypertension, potentially increasing the burden and the costs on the health care system.We designed a study to build and validate prediction models based on supervised learning and a conventional scoring system to define the risk of PA in arterial hypertension and tailor the diagnostic workup to the individual risk of each patient.We developed a clinical score and supervised machine learning algorithms in a retrospective internal cohort of 4059 patients with hypertension, and an external cohort of 584 patients with hypertension. Primary aldosteronism was confirmed by confirmatory tests, in agreement with major international recommendations, and subtype diagnosis was achieved by computed tomography and adrenal vein sampling.On the basis of 6 widely available parameters (male sex, systolic blood pressure, antihypertensive treatment, body mass index, lowest potassium, and organ damage) we developed a numerical scoring system (SToP-PA score) and 308 machine learning based models, selecting the one with the highest predicting performances. At internal validation we obtained high predictive performance with SToP-PA score (ptimised sensitivity of 90.7% for PA and 92.3% for unilateral PA) and even higher with machine learning based model (ptimised sensitivity of 96.6% for PA, and 100.0% for unilateral PA). The application of these models allowed the identification of a subgroup of patients with very low probability of having PA (0.6% with both models) and null probability of having unilateral PA. Finally, we validated our models within an independent external cohort, with performance not significantly different from internal validation.The SToP-PA score and the machine learning model accurately predict the individual pretest probability of PA in patients with hypertension, avoiding the screening for PA in up to 32.7% of patients using a machine learning algorithm, without omitting patients with unilateral UPA.
The aim of the present manuscript is to provide an overview of the most updated studies on the prevalence of primary aldosteronism in primary care and to compare these figures with the actual rate of diagnosis in clinical practice and with the prevalence of primary aldosteronism in specific subgroup of patients.Over the last 20 years the clinical spectrum of low renin hypertension and primary aldosteronism has changed dramatically. Once considered only in the presence of severe hypertension and hypokalemia, it is now well known that primary aldosteronism is not uncommon even in patients with mild forms of hypertension and/or normokalemia. Moreover, recent evidence points toward a large proportion of normotensive study participants as being affected by subclinical primary aldosteronism, which represents a strong risk factor for incident hypertension. Moreover, primary aldosteronism patients are exposed to an increased risk of cardio and cerebrovascular events and metabolic comorbidities compared with patients affected by essential hypertension. Disappointingly, primary aldosteronism remains a largely underdiagnosed and undertreated disorder.These recent findings further highlight the importance of widening the spectrum of patients who should be screened for primary aldosteronism, to reduce the cardiovascular risk associated with this medical condition.
Idiopathic scoliosis is the most common form of spinal deformity in children. However, secondary causes of scoliosis, such as ganglioneuroma, should be always considered to avoid wrong diagnosis, and further investigations are required when there are atypical signs. We report a case of ganglioneuroma misdiagnosed as idiopathic scoliosis and review the literature to identify the red flags useful for physicians during the evaluation of a child with scoliosis. On the basis of both clinical and radiographic criteria that emerged from this study, we propose an algorithm that could help in the differential diagnosis, suggesting when to perform an MRI.
Primary aldosteronism is the most common surgically curable form of hypertension. The sporadic forms of the disorder are usually caused by aldosterone overproduction from a unilateral adrenocortical aldosterone-producing adenoma or from bilateral adrenocortical hyperplasia. The main knowledge-advances in disease pathophysiology focus on pathogenic germline and somatic variants that drive the excess aldosterone production. Less clear are the molecular and cellular mechanisms that lead to an increased mass of the adrenal cortex. However, the combined application of transcriptomics, metabolomics, and epigenetics has achieved substantial insight into these processes and uncovered the evolving complexity of disrupted cell growth mechanisms in primary aldosteronism. In this review, we summarize and discuss recent progress in our understanding of mechanisms of cell death, and proliferation in the pathophysiology of primary aldosteronism.
Aldosterone-producing adenomas (APAs) are a major cause of primary aldosteronism, a common form of endocrine hypertension. Here, we demonstrate that Early Growth Response 1 (EGR1) plays a dual role in adrenal cell biology, regulating both oxidative stress and aldosterone production. Using RNA sequencing of RSL3-treated human adrenal cells and spatial transcriptomics of adrenal glands from patients with primary aldosteronism, we identify EGR1 as a key gene associated with RSL3-related oxidative stress and APAs. We show that EGR1 silencing decreases oxidative stress and increases CYP11B2 gene expression and aldosterone production in adrenal cells, while its overexpression has the opposite effects. Notably, EGR1 expression is downregulated in APAs and aldosterone-producing micronodules compared to the adjacent adrenal cortex, which correlates in part with decreased levels of oxidative stress markers. The adrenal cortex of pigs with secondary hyperaldosteronism shows decreased immunostaining of EGR1 and a marker of oxidative stress, suggesting a potential link between EGR1 expression, oxidative stress levels, and adrenocortical function. These findings reveal a novel mechanism linking EGR1 to oxidative stress regulation and aldosterone production in adrenal cells, with potential implications for the pathogenesis of APAs and other adrenocortical tumors.
Objective: Familial hyperaldosteronism type III (FH-III) is a rare autosomal dominant and clinically heterogeneous condition, that can display mild as well as severe phenotypes. Point mutations in the KCNJ5 gene, affecting the ion selectivity of the inward rectifier K+ channel 4 (Kir3.4), represent the molecular basis of FH-III. So far, five germline mu- tations in the KCNJ5 gene have been identified and functionally characterized in patients with FH-III. Objective of the present study was to characterized the effect of a de novo KCNJ5 germline substitution in vitro. Design and method: We describe the case of a girl affected by severe hyperaldosteronism. KCNJ5 gene was PCR amplified from peripheral blood and sequenced. Electrophysiological and gene expression studies were performed to establish the functional effects of the new mutation on the membrane potential and adrenal cell CYP11B2 (aldosterone synthase) expression. Results: The index case is a Caucasian girl born to nonconsanguineous parents. She came to medical attention at the age of two years because of polydipsia, polyuria and failure to thrive. The patient, affected by hypertension and hypokalemia, was diagnosed with primary aldosteronism on the basis of extremely high aldosterone levels and suppressed plasma renin activity. At the age of 19 she was on four antihypertensive medications and potassium supplements; transthoracic echocardiography revealed mildly dilated aortic root and ascending aorta without left ventricular hypertrophy. The patient consented to bilateral adrenalectomy which was performed laparoscopically. KCNJ5 sequencing in the index case and her parents revealed a de novo p.Glu145Gln germline mutation. The substitution resulted in Na+-dependent depolarization of adrenal cells and increased intracellular calcium concentration, which activated the transcription of NR4A2 and, in turn, CYP11B2. Pharmacological studies revealed that the mutant channel was insensitive to tertiapin-Q and calcium-channel blocker verapamil. Conclusions: Herein we report on the identification of a novel KCNJ5 germline mutation responsible for severe hyperaldosteronism that presented in infancy with symptoms of diabetes insipidus. The findings of this study further elucidate the etiology of FH-III and expand our knowledge of this rare condition.
