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Aldosterone-producing Adenoma (aldosterone-producing + adenoma)
Selected AbstractsPrimary Aldosteronism: Diagnosis and TreatmentJOURNAL OF CLINICAL HYPERTENSION, Issue 12 2006Eduardo Pimenta MD Recent studies have indicated a higher prevalence of primary aldosteronism (PA) than reported historically. Aldosterone excess induces sodium and fluid retention with consequential increases in blood pressure. Patients with PA are at an increased risk of developing left ventricular hypertrophy, chronic kidney disease, and endothelial dysfunction. Measurement of the plasma aldosterone/plasma renin activity ratio is an effective screening test for PA. The majority of patients with PA do not have a discernable aldosterone-producing adenoma (APA), and the aldosterone excess is considered idiopathic in etiology and/or attributed to adrenal hyperplasia. Treatment of PA includes medical therapy with mineralocorticoid receptor antagonists and adrenalectomy for patients with a unilateral APA. A reasonable treatment strategy is to attempt medical therapy in all patients with a high plasma aldosterone/PRA ratio and reserve the extensive workup needed to identify an APA for those patients whose hypertension or hypokalemia cannot be controlled medically. [source] SELECTION OF PATIENTS FOR SURGERY FOR PRIMARY ALDOSTERONISMCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 4 2008Pierre-François Plouin SUMMARY 1Primary aldosteronism is a condition characterized by renin suppression and various degrees of hypertension and hypokalemia caused by aldosterone hypersecretion. 2The adoption of the aldosterone-to-renin ratio determination as a screening test has led to an increase in the prevalence of diagnosed cases of primary aldosteronism. 3Primary aldosteronism is confirmed by the demonstration of either sustained absolute aldosterone hypersecretion, or non-suppressible aldosterone hypersecretion. 4Computed tomography and adrenal vein sampling can then be used to distinguish between idiopathic primary aldosteronism and the surgically remediable forms: aldosterone-producing adenoma and primary adrenal hyperplasia. 5In patients with aldosterone-producing adenoma or primary adrenal hyperplasia, unilateral adrenalectomy generally results in the normalization of aldosterone secretion and kalemia, but normotension is achieved in only half of the cases. Nevertheless, in many cases without hypertension cure, adrenalectomy leads to an improvement in hypertension control with lower blood pressure levels and/or less antihypertensive medication. [source] Retroperitoneoscopic partial adrenalectomy for small adrenal tumours (,1 cm): the Ruijin clinical experience in 88 patientsBJU INTERNATIONAL, Issue 6 2010Xiao-jing Wang Study Type , Therapy (case series) Level of Evidence 4 OBJECTIVE To present our experience of retroperitoneoscopic partial adrenalectomy (RPA) for small adrenal tumours, as with modern imaging methods small adrenal lesions are being diagnosed more commonly, and retroperitoneoscopic adrenal surgery for small adrenal tumours (,1 cm) can be challenging. PATIENTS AND METHODS We retrospectively reviewed the records of 389 consecutive retroperitoneoscopic adrenalectomies from September 2005 to December 2008, 88 of which were small adrenal tumours and treated by RPA. Ultrasonography and computed tomography (CT) were used in all patients before RPA, and magnetic resonance imaging or positron emission tomography/CT in some patients. We used RPA for adrenal tumours and total adrenalectomy for adrenal cancer. During the surgery, the internal part of the adrenal gland close to the retroperitoneum was freed first, and the whole adrenal tissue was dissected completely. The preoperative imaging was important in these procedures. RESULTS There were no deaths; conversions to open surgery were necessary in four patients (4.5%), the reasons being a missing target in two, massive haemorrhage caused by central adrenal vein injury in one, and severe adhesion in one. The mean (range) size of the adrenal tumours was 0.7 (0.5,1.0) cm, including 69 aldosterone-producing adenomas, 11 nonfunctional adrenal adenomas, three Cushing syndrome, two phaeochromocytomas, two myelolipomas and one melanoma. The operative duration in the initial 38 cases was significantly longer than that in the subsequent 50 (P < 0.01). However, there was no significant correlation between estimated blood loss and the number of procedures. Tumour size did not correlate with estimated blood loss and operative duration. There was no significant correlation between body mass index and operative duration. CONCLUSION RPA is a safe, effective and minimally invasive therapeutic option for patients with small adrenal tumours. With improved operative technique the RPA has been completed in more quickly. Freeing the internal part of the adrenal gland close to the retroperitoneum first, and exploring the whole adrenal tissue during surgery are the key points of RPA. The location of the small adrenal tumour can be different from that shown on imaging before surgery, and the abnormality of the adrenal gland should be considered. [source] The role of TASK1 in aldosterone production and its expression in normal adrenal and aldosterone-producing adenomasCLINICAL ENDOCRINOLOGY, Issue 1 2010Edson F. Nogueira Summary Objectives, Aldosterone production in the adrenal glomerulosa is mainly regulated by angiotensin II and K+. Adrenal glomerulosa cells are uniquely sensitive to extracellular K+. Genetic deletion of subunits of K+ -selective leak-channels (KCNK), TASK1 and/or TASK3, in mice generates animals with hyperaldosteronism and histological changes in the adrenal cortex. Herein, we studied the expression of TASK1 in human adrenocortical cells, as well as its role in aldosterone production in H295R cells. Design, TASK1 expression was investigated by comparative microarray analysis of aldosterone-producing adenomas (APA) and normal adrenals (NAs). The effects of TASK1 knockdown by siRNA transfection were investigated in H295R cells. Fluo-4 fluorescent measurements of intracellular Ca2 + and pharmacological inhibition of Ca2 + -dependent calmodulin kinases (CaMK) were performed to better define the effects of TASK1 on Ca2 + signalling pathways. Results, Microarray analysis of APA and NA showed similar expression of TASK1 between these two groups. However, in APA, NA and H295R cells the expression of TASK1 was predominant when compared with other KCNK family members. Knockdown of TASK1 (with siRNA) induced the expression of steroidogenic acute regulatory (StAR) protein and aldosterone synthase (CYP11B2), and also stimulated pregnenolone and aldosterone production. Cells transfected with siTASK1 had increased intracellular Ca2 + , leading to activation of CaMK and increased expression of CYP11B2. Conclusions, Our study reveals the predominant expression of TASK1 over other KCNK family genes in the human adrenal cortex. Herein, we also described the role of TASK1 in the regulation of human aldosterone production through regulation of intracellular Ca2 + and CaMK signalling pathways. [source] |