Primary aldosteronism. Results of surgical treatment

Developing the novel diagnostic model and potential drugs by integrating bioinformatics and machine learning for aldosterone-producing adenomas

Background: Aldosterone-producing adenomas (APA) are a common cause of primary aldosteronism (PA), a clinical syndrome characterized by hypertension and electrolyte disturbances. If untreated, it may lead to serious cardiovascular complications. Therefore, there is an urgent need for potential biomarkers and targeted drugs for the diagnosis and treatment of aldosteronism. Methods: We downloaded two datasets (GSE156931 and GSE60042) from the GEO database and merged them by de-batch effect, then screened the top50 of differential genes using PPI and enriched them, followed by screening the Aldosterone adenoma-related genes (ARGs) in the top50 using three machine learning algorithms. We performed GSEA analysis on the ARGs separately and constructed artificial neural networks based on the ARGs. Finally, the Enrich platform was utilized to identify drugs with potential therapeutic effects on APA by tARGseting the ARGs. Results: We identified 190 differential genes by differential analysis, and then identified the top50 genes by PPI, and the enrichment analysis showed that they were mainly enriched in amino acid metabolic pathways. Then three machine learning algorithms identified five ARGs, namely, SST, RAB3C, PPY, CYP3A4, CDH10, and the ANN constructed on the basis of these five ARGs had better diagnostic effect on APA, in which the AUC of the training set is 1 and the AUC of the validation set is 0.755. And then the Enrich platform identified drugs tARGseting the ARGs with potential therapeutic effects on APA. Conclusion: We identified five ARGs for APA through bioinformatic analysis and constructed Artificial neural network (ANN) based on them with better diagnostic effects, and identified drugs with potential therapeutic effects on APA by tARGseting these ARGs. Our study provides more options for the diagnosis and treatment of APA.

Hypertension outcomes of adrenalectomy for unilateral primary aldosteronism

PURPOSE

To evaluate laboratory and clinical results after unilateral adrenalectomy in patients with primary aldosteronism (PHA).

METHODS

A cross-sectional analysis was performed using data from patients who underwent transperitoneal laparoscopic adrenalectomy for PHA, between January 2008 and December 2019. Surgical indications were based on adrenal venous sampling without ACTH stimulation. Analyses included patient demographics; preoperative clinical, pharmacological, laboratory, and radiological data; and postoperative results assessed after a median of 4 months. Antihypertensive drug use was quantified by estimating the daily defined dose (DDD) of antihypertensive medication, thus enabling standardized comparison of dosage between the drug classes. Statistical assessments included univariable and multivariable logistic regression analysis.

RESULTS

This study enrolled 87 patients. The patients were taking 5.4 DDD of antihypertensive medication before surgery, and 3.0 DDD after surgery. Complete biochemical success of surgery was reached 67 patients (77%), 19 patients (22%) had partial biochemical success. Complete clinical success with normalization of blood pressure and withdrawal of all antihypertensive drugs was achieved in 19 patients (22%). 57 patients (65%) exhibited a reduction of DDD after surgery and/or improvement of blood pressure-partial clinical success. Thus, in 76 (87%) of all enrolled patients, surgery had an overall positive effect on hypertension control. Multivariable logistic regression showed that complete clinical success was independently associated with female gender and baseline sum of antihypertensive drugs DDD < 4.

CONCLUSION

A majority of patients undergoing unilateral adrenalectomy for PHA achieved markedly improved hypertension control, despite almost halving their antihypertensive medication. Almost a quarter of patients were cured and able to cease using all antihypertensive drugs.

Performance evaluation of scoring systems for predicting post-operative hypertension cure in primary aldosteronism

OBJECTIVE

Hypertension cure following adrenalectomy in unilateral primary aldosteronism is not guaranteed. Its likelihood is associated with pre-operative parameters, which have been variably combined in six different predictive scoring systems. The relative performance of these systems is currently unknown. The objective of this work was to identify the best performing scoring system for predicting hypertension cure following adrenalectomy for primary aldosteronism.

DESIGN

Retrospective analysis in a single tertiary referral centre.

PATIENTS

Eighty-seven adult patients with unilateral primary aldosteronism who had undergone adrenalectomy between 2004 and 2018 for whom complete data sets were available to calculate all scoring systems.

MEASUREMENTS

Prediction of hypertension cure by each of the six scoring systems.

RESULTS

Hypertension cure was achieved in 36/87 (41.4%) patients within the first post-operative year, which fell to 18/71 (25.4%) patients at final follow-up (median 53 months, P = .002). Analysis of receiver operating characteristic area under the curves for the different scoring systems identified a difference in performance at early, but not late, follow-up. For all systems, the area under the curve was lower at early compared with late follow-up and compared to performance in the cohorts in which they were originally defined.

CONCLUSIONS

No single scoring system performed significantly better than all others when applied in our cohort, although two did display particular advantages. It remains to be determined how best such scoring systems can be incorporated into the routine clinical care of patients with PA.

Endocrine hypertension secondary to adrenal tumors: clinical course and predictive factors of clinical remission

PURPOSE

Endocrinopathies constitute ~ 10% of secondary hypertension (SH) etiologies. Primary aldosteronism, pheochromocytoma (PHEO), and Cushing's syndrome are common causes. Early identification and treatment result in resolution/improvement of SH. The aim of this study was to characterize the clinical course, outcomes, and remission-associated prognostic factors of SH related to adrenal tumors.

METHODS

Retrospective cohort study including patients with SH who underwent adrenalectomy from 2000 to 2019. Postoperative outcomes were analyzed. Remission was defined as normalization of blood pressure without drug use.

RESULTS

Eighty-three patients with SH were included. Mean ± SD age was 38.8 ± 14.2 years and 75.9% were women. Diagnosis was PHEO in 35 patients (42.2%), aldosteronoma (APA) in 28 (33.7%), cortisol producing adenoma (CPA) in 16 (19.3%), and ACTH-dependent Cushing's in 4 (4.8%). Laparoscopic adrenalectomy was performed in 81 (97.6%) patients. Mean ± SD follow-up was 57.4 ± 49.6 months (range 1-232). Surgical morbidity occurred in 7.2% of patients and there was no mortality. Remission of SH occurred in 61(73.5%): 100% of ACTH-dependent Cushing's, 85.7% of PHEO, 68.8% of CPA, and 57.1% of APA. Biochemical phenotype and the combination of larger tumor size, number of antihypertensive drugs, male gender, older age, obesity, and preoperative SH for more than 5 years were associated with less likely clinical remission in patients with APA (p = 0.004), CPA (p < 0.0001), and PHEO (p < 0.0001).

CONCLUSION

SH remission rates are 57-100% after adrenalectomy. Several prognostic factors could be used to predict SH control. Adrenalectomy provides good clinical outcome and must be considered a treatment option in all surgical candidates.

The Management of Primary Hyperaldosteronism in a Poor Technology Environment

We report a case of Conn's adenoma in a 35-year-old female successfully managed in a poor hospital technology environment.

Trends in blood pressure-related outcomes after adrenalectomy in patients with primary aldosteronism: A systematic review

BACKGROUND

Decrease in blood pressure (BP) is the major goal of adrenalectomy for primary aldosteronism. Nevertheless, the optimal timing to assess these outcomes and the needed duration of follow-up are uncertain. We systematically reviewed the literature regarding trends in BP-related outcomes during follow-up after adrenalectomy.

METHODS

A systematic literature search of medical literature from PubMed, Embase and the Cochrane Library regarding BP-related outcomes (i.e. cure of hypertension rates, BP and antihypertensives) was performed. The Quality In Prognosis Studies risk of bias tool was used.

RESULTS

Of the 2057 identified records, 13 articles met the inclusion criteria. Overall study quality was low. In multiple studies, the biggest decrease in BP was shown within the first month(s) after adrenalectomy and afterwards BP often remained stable during long-term follow-up.

CONCLUSIONS

Based on the available studies one might suggest that long follow-up is unnecessary, since outcomes seem to stabilize within the first months.

Primary Aldosteronism Diagnosis and Management: A Clinical Approach

Primary aldosteronism used to be considered a rare cause of secondary hypertension. However, accruing evidence indicates that primary aldosteronism is more common than previously recognized. The implications of this increased prevalence are important to public health because autonomous aldosterone production contributes to cardiovascular disease and can be treated in a targeted manner. This article focuses on clinical approaches for diagnosing primary aldosteronism more frequently and earlier in its course, as well as practical treatment objectives to reduce the risk for incident cardiovascular disease.

Effectiveness of Thermal Ablation for Aldosterone-Producing Adrenal Adenoma: A Systematic Review and Meta-Analysis of Clinical and Biochemical Parameters

PURPOSE

To assess the effectiveness of thermal ablation for aldosterone-producing adrenal adenoma.

MATERIALS AND METHODS

A systematic search of the PubMed and CINAHL databases was performed to identify studies of thermal ablation for adrenal adenomas. Random effects meta-analysis models were used to compare pre- and post-treatment values of the following outcomes: systolic blood pressure (SBP), diastolic blood pressure (DBP), use of antihypertensive medications, and biochemical parameters (plasma aldosterone levels, aldosterone-to-renin ratio, and potassium levels). The rate of hypertension (HTN) resolution and improvement were also evaluated.

RESULTS

A total of 89 patients from 7 studies were included in the analysis. The mean postablation follow-up duration was 45.8 months. Pooled data analysis revealed a statistically significant decrease in SBP (-29.06 mm Hg; 95% confidence interval [CI], -33.93 to -24.19), DBP (-16.03 mm Hg; 95% CI, -18.33 to -13.73), and the number of antihypertensive medications used (-1.43; 95% CI, -1.97 to -0.89) after ablation. Biochemical parameters had returned to normal ranges after ablation in all studies. The cumulative rate of resolution or improvement in HTN status was 75.3%. On metaregression analysis, there was no statistically significant association between postablation blood pressure changes or serum aldosterone levels and study follow-up duration.

CONCLUSIONS

Thermal ablation for aldosterone-producing adrenal adenoma can be effective in controlling blood pressure, reducing the need for antihypertensive medications, and normalizing hormone secretion. Further higher-quality evidence is needed to confirm these results.

Primary Aldosteronism: Cardiovascular Outcomes Pre- and Post-treatment

PURPOSE OF REVIEW

Primary aldosteronism (PA) is a common form of hypertension characterized by autonomous aldosterone secretion from one or both adrenal glands. The purpose of this review is to synthesize recent research findings regarding cardiovascular disease risk in PA both pre- and post-targeted therapy.

RECENT FINDINGS

Previously considered a rare disease, recent prevalence studies demonstrate that PA is actually a very common, yet vastly under-diagnosed, etiology of hypertension. Prior to targeted therapy, PA is associated with substantially higher rates of cardiovascular disease compared with essential hypertension. Surgical adrenalectomy is highly effective in curing or improving hypertension as well as mitigating cardiovascular disease risk in patients with unilateral PA. For the remainder of PA patients, MR antagonists are recommended; however, several recent studies have brought into question their effectiveness in improving cardiovascular outcomes. PA is a common cause of hypertension that leads to disproportionately high rates of cardiovascular disease. Future studies are needed to enhance the clinical approach to both identification and treatment of patients with PA to optimize long-term cardiovascular outcomes.

The Expanding Spectrum of Primary Aldosteronism: Implications for Diagnosis, Pathogenesis, and Treatment

Primary aldosteronism is characterized by aldosterone secretion that is independent of renin and angiotensin II and sodium status. The deleterious effects of primary aldosteronism are mediated by excessive activation of the mineralocorticoid receptor that results in the well-known consequences of volume expansion, hypertension, hypokalemia, and metabolic alkalosis, but it also increases the risk for cardiovascular and kidney disease, as well as death. For decades, the approaches to defining, diagnosing, and treating primary aldosteronism have been relatively constant and generally focused on detecting and treating the more severe presentations of the disease. However, emerging evidence suggests that the prevalence of primary aldosteronism is much greater than previously recognized, and that milder and nonclassical forms of renin-independent aldosterone secretion that impart heightened cardiovascular risk may be common. Public health efforts to prevent aldosterone-mediated end-organ disease will require improved capabilities to diagnose all forms of primary aldosteronism while optimizing the treatment approaches such that the excess risk for cardiovascular and kidney disease is adequately mitigated. In this review, we present a physiologic approach to considering the diagnosis, pathogenesis, and treatment of primary aldosteronism. We review evidence suggesting that primary aldosteronism manifests across a wide spectrum of severity, ranging from mild to overt, that correlates with cardiovascular risk. Furthermore, we review emerging evidence from genetic studies that begin to provide a theoretical explanation for the pathogenesis of primary aldosteronism and a link to its phenotypic severity spectrum and prevalence. Finally, we review human studies that provide insights into the optimal approach toward the treatment of primary aldosteronism.

Radiofrequency ablation compared with laparoscopic adrenalectomy for aldosterone-producing adenoma

BACKGROUND

Radiofrequency ablation (RFA) is an emerging treatment for primary aldosteronism owing to aldosterone-producing adenoma. Whether RFA could be an alternative treatment to laparoscopic adrenalectomy is unknown.

METHODS

This was a retrospective comparative study in patients with aldosterone-producing adenoma undergoing either laparoscopic adrenalectomy or CT-guided percutaneous RFA between 2004 and 2012. Short-term outcomes and long-term resolution rates of primary aldosteronism (normalized aldosterone to renin ratio), hypokalaemia and hypertension (BP lower than 140/90 mmHg without antihypertensive medical therapy) were evaluated.

RESULTS

Some 63 patients were included, 27 in the laparoscopic adrenalectomy group and 36 in the RFA group. RFA was associated with shorter duration of operation (median 12 versus 124 min; P < 0·001), shorter hospital stay (2 versus 4 days; P < 0·001), lower analgesic requirements (13 of 36 versus 23 of 27 patients; P < 0·001) and earlier resumption of work (median 4 versus 14 days; P = 0·006). Morbidity rates were similar in the two groups. With median follow-up of 5·7 (range 1·9-10·6) years, resolution of primary aldosteronism was seen in 33 of 36 patients treated with RFA and all 27 patients who had laparoscopic adrenalectomy (P = 0·180). Hypertension was resolved less frequently after treatment with RFA compared with laparoscopic adrenalectomy (13 of 36 versus 19 of 27 patients; P = 0·007). Hypokalaemia was resolved in all patients.

CONCLUSION

For patients with aldosterone-producing adenoma the efficacy of resolution of primary aldosteronism and hypertension was inferior after treatment with RFA compared with laparoscopic adrenalectomy.

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.

Adrenal nodularity and somatic mutations in primary aldosteronism: one node is the culprit?

CONTEXT

Somatic mutations in genes that influence cell entry of calcium have been identified in aldosterone-producing adenomas (APAs) of adrenal cortex in primary aldosteronism (PA). Many adrenal glands removed for suspicion of APA do not contain a single adenoma but nodular hyperplasia.

OBJECTIVE

The objective of the study was to assess multinodularity and phenotypic and genotypic characteristics of adrenals removed because of the suspicion of APAs.

DESIGN AND METHODS

We assessed the adrenals of 53 PA patients for histopathological characteristics and immunohistochemistry for aldosterone (P450C18) and cortisol (P450C11) synthesis and for KCNJ5, ATP1A1, ATP2B3, and CACNA1D mutations in microdissected nodi.

RESULTS

Glands contained a solitary adenoma in 43% and nodular hyperplasia in 53% of cases. Most adrenal glands contained only one nodule positive for P450C18 expression, with all other nodules negative. KCNJ5 mutations were present in 22 of 53 adrenals (13 adenoma and nine multinodular adrenals). An ATP1A1 and a CACNA1D mutation were found in one multinodular gland each and an ATP2B3 mutation in five APA-containing glands. Mutations were always located in the P450C18-positive nodule. In one gland two nodules containing two different KCNJ5 mutations were present. Zona fasciculata-like cells were more typical for KCNJ5 mutation-containing nodules and zona glomerulosa-like cells for the other three genes.

CONCLUSIONS

Somatic mutations in KCNJ5, ATP1A1, or CACNA1D genes are not limited to APAs but are also found in the more frequent multinodular adrenals. In multinodular glands, only one nodule harbors a mutation. This suggests that the occurrence of a mutation and nodule formation are independent processes. The implications for clinical management remain to be determined.

Persistent hypertension after adrenalectomy for an aldosterone-producing adenoma: weight as a critical prognostic factor for aldosterone's lasting effect on the cardiac and vascular systems

BACKGROUND

Primary aldosteronism caused by an aldosterone producing adrenal tumor/aldosteronoma (APA), is a potentially curable form of hypertension, via unilateral adrenalectomy. Resolution of hypertension (HTN) is not as prevalent after tumor resection, as are the normalization of aldosterone secretion, hypokalemia, and other metabolic abnormalities. Here, we review the immediate and long-term medical outcomes of laparoscopic adrenalectomy in patients with an APA, and attempt to identify any distinctive sex differences in the management of resistant HTN.

METHODS

We performed a retrospective review of the prospective adrenal database at the University of Wisconsin between January 2001 and October 2010. Of the 165 adrenalectomies performed, 32 were for the resection of an APA. Patients were grouped according to their postoperative HTN status. Those patients with normal blood pressure (≤120/80 mm Hg) and on no antihypertensive medication (CURE) were compared with those who continued to require medication for blood pressure control (HTN). We evaluated sex, age, body mass index, tumor size, duration of time with high blood pressure, and the differences in systolic and diastolic blood pressure following adrenalectomy. Statistical analysis was performed using Student's t-test. Statistical significance was defined as a P value of <0.05.

RESULTS

We identified 32 patients with an APA based on biochemical and radiographic studies, two patients were excluded, due to missing data. There were 19 males (63%) and 11 (37%) females, with a mean age was 48.3 ± 2.1 y, and mean tumor size was 24 ± 3 mm. Postoperatively, patients required significantly fewer antihypertensive medications (1.5 ± 0.2 versus 3.3 ± 0.3, P < 0.001). Nine patients (31%) had complete resolution of their HTN, requiring no postoperative antihypertensive medication. The only significant difference between the sexes, was a lower body mass index in women (27.6 ± 1.7 versus 33.4 ± 2.1 kg/m(2), P = 0.04). Ninety percent of the cohort had at least a 20 mm Hg decline in their systolic blood pressure postoperatively, placing them in the prehypertensive or normal blood pressure categories. Sixty-six percent of the CURE patients required at least 6 mo for resolution of their HTN. All 20 patients who presented with hypokalemia, had immediate resolution postoperatively and did not require continuance of the preoperative spironolactone or potassium supplementation.

CONCLUSIONS

Laparoscopic adrenalectomy for aldosterone producing adenoma results in the normalization of, or more readily manageable blood pressure in 90% of patients, within 6 mo. Metabolic disturbances are immediately corrected with tumor resection. Weight is an important contributing factor in resolving HTN.

Outcome of surgery for primary hyperaldosteronism

BACKGROUND

Primary hyperaldosteronism (PHA) frequently causes secondary hypertension and is a surgically amenable disease if associated with unilateral adenoma. Patients who underwent laparoscopic adrenalectomy at the authors' department were followed to identify clinical parameters that predict resolution of hypertension.

METHODS

All patients with PHA and adrenalectomy from 1993 to 2009 were identified. Charts and follow-up data were reviewed for clinical parameters and hormone levels. Univariate and multivariate analysis were performed with SPSS 15.0.

RESULTS

A cohort of 30 female and 24 male patients underwent laparoscopic adrenalectomy. Hypokalemia was observed in 47/54 (87%) patients. Twenty patients (37%) were cured without any further need of antihypertensive medication, 20 (37%) patients experienced an improvement in hypertension, and 14 (26%) patients remain unaffected. Consequently, hypertension was resolved or improved in 40/54 (74%) patients. A shorter duration of hypertension (<6 years), the number of antihypertensive drugs (<3), and the serum creatinine level (<1.3 mmol/l) were independent predictors of resolution of hypertension in a multivariate analysis. At final follow-up after a mean of 49 ± 40 months, resolution of hypertension was observed in 17/30 (57%) patients. Interestingly, in 10/17 patients a period longer than 12 months was required before a resolution of hypertension was observed. Coexistent hyperplasia, which was observed in 30% of patients, did not correlate with outcome.

CONCLUSIONS

In 50% of patients with PHA, hypertension resolves after laparoscopic adrenalectomy, but the process may require more than 12 months. Patients with a duration of hypertension of more than 6 years, more than 3 antihypertensive drugs, and elevated serum creatinine have a higher risk of persistent hypertension after surgery. Coexistent hyperplasia in the resected adrenal gland is not associated with persistent hypertension.

Kidney in primary aldosteronism: A key determinant of treatment outcome

Recently, it has been suggested that primary aldosteronism (PA) is associated with a variety of cardiac, vascular, metabolic, and renal sequelae that reflect the capability of elevated aldosterone to induce organ damage beyond that induced by hypertension itself. The evidence supporting of these views has been obtained from experiments conducted in rodents and clinical studies conducted in patients with this endocrine disorder. It has been suggested that untoward effects of high-salt intake are dependent on activation of mineralocorticoid receptors that might result from increased oxidative stress and changes in the intracellular redox potential. Unilateral adrenalectomy or treatment with mineralocorticoid receptor antagonists are the current options for treating an aldosterone-producing adrenal adenoma or idiopathic adrenal hyperplasia. Treatments are largely effective in correcting hypertension and hypokalemia, and currently available information on their capability to prevent deterioration of renal function indicates that surgery and medical treatment are equally beneficial in the long term. This editorial review will focus on the renal aspects of PA and highlights the role of the kidney as a key determinant of both adaptation to aldosterone-induced volume retention and response of blood pressure to treatment.

Primary aldosteronism: from bench to bedside

Primary aldosteronism is now thought to be the commonest potentially curable and specifically treatable form of hypertension. The detection of primary aldosteronism is of utmost importance not only because it provides an opportunity for a targeted treatment, but also because it has been demonstrated that patients with primary aldosteronism are more prone to cardiovascular events and target organ damage than essential hypertensives. Normalization of blood pressure and hypokalemia should not be the only goal of treatment. Normalization of circulating aldosterone or mineralocorticoid blockade is necessary to prevent aldosterone-induced tissue damage that occurs independent of blood pressure. This review will focus on the current understanding and comprehensive management review of primary aldosteronism, highlighting the new evidence that has become recently available.

Treatment of primary aldosteronism: Where are we now?

Primary aldosteronism (PA) is an important cause of secondary hypertension, is being increasingly diagnosed and may account for more than 10% of hypertensive patients, both in primary care and in referral centers. Aldosterone excess is associated with adverse cardiovascular, renal and metabolic effects that are in part hypertension-independent. Laparoscopic adrenalectomy remains the mainstay of treatment for unilateral forms of PA, whereas medical treatment is recommended for bilateral forms of PA. However, a favourable surgical outcome depends on several factors and many patients are not suitable for this treatment. On the other hand, surgery in patients considered to have bilateral PA may contribute to better blood pressure control. In this review, established and novel strategies for the management of different types of PA are discussed.

Treatment of primary aldosteronism

The prevalence of primary hyperaldosteronism approaches 10% of all hypertensive patients, and besides efficient diagnostic procedures, effective treatment is of increasing importance to reverse increased morbidity and mortality. Aldosterone-producing adenoma and unilateral adrenal hyperplasia are amenable to cure by endoscopic adrenalectomy. Bilateral adrenal hyperplasia (micro- or macronodular), which comprises two-thirds of primary hyperaldosteronism, is treated primarily by mineralocorticoid receptor antagonists (starting dose 12.5-25mg/day spironolactone with titration up to 100mg/day, alternatively 50-100mg/day eplerenone). If blood pressure is not normalised by this first-line treatment, additional treatment with potassium-sparing diuretics (amiloride or triamterene) or calcium channel antagonists is necessary. The start of medication should be closely monitored by serum electrolyte and creatinine controls.

Diagnosis and surgical management for primary hyperaldosteronism

The evaluation of primary hyperaldosteronism presents a challenge to endocrinologists, radiologists, and urologic surgeons. A multidisciplinary approach with biochemical screening and radiologic evaluation is essential in order to assess the nature and function of hypersecreting adrenal glands. Furthermore, it is of great importance to identify individuals that are morbidly affected by aldosterone hypersecretion. Traditionally, open adrenalectomy was the preferred option for these patients. More recently, laparoscopic adrenalectomy has offered a minimally invasive approach, with its resultant advantages of improved perioperative parameters. Herein we describe the evaluation and surgical management for patients with a suspected diagnosis of primary hyperaldosteronism.

Aldosteronomas--state of the art

Primary aldosteronism (PA) is the most common cause of secondary hypertension in nonsmokers. Widespread screening of unselected hypertensives has identified PA in as many as 15% of patients. With such screening efforts using the PAC/PRA ratio and PAC, the widespread prevalence of the disease has become apparent while the relative percentage of APA has decreased. PA is confirmed by demonstrating lack of aldosterone suppressibility with sodium loading. Subtype evaluation is best achieved with high resolution CT scanning and AVS in the appropriate setting. In patients with PA and a unilateral source of aldosterone excess, laparoscopic adrenalectomy is the treatment of choice with excellent outcomes and low morbidity as compared with older open approaches. Patients with IHA, or those not amenable or agreeable to surgery, are best managed with a MR antagonist.

Small tumor size as favorable prognostic factor after adrenalectomy in Conn's adenoma

OBJECTIVE

Primary aldosteronism (PA) due to aldosterone-producing adenoma (APA) is the most common curable form of secondary hypertension.

DESIGN

In order to evaluate blood pressure outcome after adrenalectomy for APA and to identify new favorable prognostic factors, data from 42 consecutive APA patients who underwent adrenalectomy were collected from 2005 to 2007.

METHODS

Renin-angiotensin-aldosterone system (upright and postsaline infusion test), serum and urinary electrolytes, office and ambulatory blood pressure monitoring were evaluated at baseline and after a follow-up of 2.7+/-2.2 years. Drug history and adenoma size at morphological evaluation were also collected.

RESULTS

Multiple regression analysis showed that, before surgery, patients with a small adenoma (diameter <20 mm) displayed higher postsaline aldosterone values (P=0.0001), and lower serum potassium levels (P=0.020), than patients with adenoma >20 mm. Before surgery, mineralocorticoid receptor (MR) antagonists were used in patients with small APA in greater percentage than patients with bigger adenomas (64 vs 30% respectively, P=0.037). At follow-up, blood pressure normalized in 63% of the subjects. Recovered patients had a shorter duration of hypertension (P=0.038), and a smaller adenoma size (P=0.035). Receiver operating characteristic curves showed that a duration of hypertension <or=6 years and an APA size <20 mm were the best predictors of blood pressure normalization. Patients with APA <20 mm showed the complete restoration of blood pressure circadian rhythm.

CONCLUSIONS

The presence of APA <20 mm, duration of hypertension equal or less than 6 years, and preoperative MR antagonists use are favorable prognostic factors for hypertension recovery after adrenalectomy.

Long-term results of laparoscopic adrenalectomy for primary aldosteronism

BACKGROUND

The management of primary aldosteronism is currently achieved by both medical and surgical treatment. Laparoscopy has in recent years unquestionably become the gold standard in adrenal surgery for benign lesions. This study aims to evaluate our clinical results among patients who underwent laparoscopic adrenalectomy (LA) for primary aldosteronism.

METHODS

From January 1994 to January 2006, amid LA series, 59 primary aldosteronism patients were treated in our institution. Patients were 33 males and 26 females with mean age 49.3 yr (19-78). The mean body mass index was 25.9 kg/m2 (20.5-33.3). The mean size of lesion was 2.9 cm (1-5.5). Clinical symptoms were as follows: hypertension and symptomatic/asymptomatic hypokalemia (54), hypokalemia (5).

RESULTS

Thirty-five left and 24 right LA were performed. On the left side, 22 procedures were carried out by anterior approach, 9 by anterior submesocolic route, and 4 by means of flank approach. All right procedures were completed by the anterior supine approach. The mean operative time was 103.5 min for left and 92.8 min for right adrenalectomy. There was one major complication, a colonic post-operative fistula, regarding a left adrenalectomy case. The mean post-operative hospital stay was 3 days (1-9). The cure rate of hypertension and hypokalemia was similar to the current literature results.

CONCLUSIONS

LA is a safe and effective option in the treatment of primary aldosteronism. Appropriate selection of patients, larger adrenal masses and duration of symptoms are determining factors in the success rate of hypertension management.

Case detection, diagnosis, and treatment of patients with primary aldosteronism: an endocrine society clinical practice guideline

OBJECTIVE

Our objective was to develop clinical practice guidelines for the diagnosis and treatment of patients with primary aldosteronism.

PARTICIPANTS

The Task Force comprised a chair, selected by the Clinical Guidelines Subcommittee (CGS) of The Endocrine Society, six additional experts, one methodologist, and a medical writer. The Task Force received no corporate funding or remuneration.

EVIDENCE

Systematic reviews of available evidence were used to formulate the key treatment and prevention recommendations. We used the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) 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

Consensus was guided by systematic reviews of evidence and discussions during one group meeting, several conference calls, and multiple e-mail communications. The drafts prepared by the task force with the help of a medical writer were reviewed successively by The Endocrine Society's CGS, Clinical Affairs Core Committee (CACC), and Council. The version approved by the CGS and CACC was placed on The Endocrine Society's Web site for comments by members. At each stage of review, the Task Force received written comments and incorporated needed changes.

CONCLUSIONS

We recommend case detection of primary aldosteronism be sought in higher risk groups of hypertensive patients and those with hypokalemia by determining the aldosterone-renin ratio under standard conditions and that the condition be confirmed/excluded by one of four commonly used confirmatory tests. 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 the presence of a unilateral form of primary aldosteronism should be established/excluded by bilateral adrenal venous sampling by an experienced radiologist and, where present, optimally treated by laparoscopic adrenalectomy. We recommend that patients with bilateral adrenal hyperplasia, or those unsuitable for surgery, optimally be treated medically by mineralocorticoid receptor antagonists.

Urinary aldosterone-to-active-renin ratio: a useful tool for predicting resolution of hypertension after adrenalectomy in patients with aldosterone-producing adenomas

BACKGROUND

The purpose of this study was to determine the preoperative clinical and biological factors that predict the clinical outcomes after surgery, in subjects with aldosterone-producing adenomas (APAs).

METHODS

Fifty-eight patients (mean age 52 +/- 11 years) with APA were followed up for 43 +/- 13 months after they had undergone unilateral adrenalectomy. The subjects were classified as "cured" (n = 23) if the blood pressure (BP) was <140/90 mm Hg without postoperative medication, "normalized" (n = 20) if BP was <140/90 mm Hg with antihypertensive therapy, and "uncontrolled" (n = 15) if a BP of < or =140/90 mm Hg was not achieved despite intensive therapy.

RESULTS

The cured patients had a significantly lower mean preoperative age, cardiac mass, and serum creatinine (P < 0.001) than the other subjects. The main independent predictors of surgical curability were: age (P < 0.01), low serum potassium (P < 0.0001), and the urinary aldosterone-to-active-renin (UAAR) ratio (P < 0.008). Among the hormonal parameters, the UAAR ratio provided the best area under the receiver operating-characteristics curve (0.802 (confidence interval (CI) 95%: 0.676-0.944)). For a cutoff value of 15, the positive and negative predictive values of the UAAR ratio were 85 and 92%, respectively. In the study population as a whole, surgical treatment restored the age-systolic BP (SBP) relationship (P < 0.006), which was insignificant before surgery.

CONCLUSIONS

Although all the subjects showed lowering of BP after surgery, and the age-BP relationship was restored, the long-term cure rate of APA subjects was 40%. The UAAR ratio, by comparison with other classical hormonal features of primary aldosteronism, was the best independent predictor of the cure of hypertension after adrenalectomy.

The aldosteronoma resolution score: predicting complete resolution of hypertension after adrenalectomy for aldosteronoma

OBJECTIVE

To develop a prediction model using information readily available, at clinical presentation, which could determine whether patients with aldosterone-producing adenomas would have complete resolution of hypertension after adrenalectomy.

BACKGROUND

Primary aldosteronism is the most common curable cause of secondary hypertension. However, a large number of patients continue to require antihypertensive medications to control their blood pressure. Differentiating patients that will have complete resolution of hypertension without the need for antihypertensive medications from patients that will require continued use of antihypertensive medications is difficult before adrenalectomy.

METHODS

The predictive logistic regression model was derived using data on 100 patients who underwent adrenalectomy for primary aldosteronism at one tertiary medical center and was externally validated using an independent series of 67 patients from another center.

RESULTS

Clinical features were similar for patients in the derivation and validation groups. Four readily available predictors (2 or fewer antihypertensive medications, body mass index < or =25 kg/m, duration of hypertension < or =6 years, and female sex) yielded the best predictive model for complete resolution of hypertension after adrenalectomy. Based on the resulting 4-item aldosteronoma resolution score (ARS), 3 likelihood levels for complete resolution were identified: low (0-1), medium (2-3), and high (4-5) with a predictive accuracy of 27%, 46%, and 75%, respectively.

CONCLUSION

The ARS accurately identifies individuals at low (ARS < or =1) or high (ARS > or =4) likelihood of complete resolution of hypertension without further need of lifelong antihypertensive medications after adrenalectomy for aldosteronoma. This scoring system can help clinicians objectively inform patients of likely clinical outcomes before surgical intervention.

Outcomes of laparoscopic adrenalectomy for hyperaldosteronism

BACKGROUND

Primary hyperaldosteronism is a frequent cause of resistant hypertension and is amenable to surgical intervention when caused by a unilateral aldosterone-producing adenoma. The aim of this study was to investigate the long-term results of laparoscopic adrenalectomy in the control of hypertension caused by primary hyperaldosteronism.

METHODS

A prospective case series of patients undergoing laparoscopic adrenalectomy for hyperaldosteronism was studied. Blood pressure (BP), serum aldosterone levels, plasma renin activity, serum potassium and antihypertensive requirement were measured before and after adrenalectomy.

RESULTS

Sixty-two patients with hyperaldosteronism underwent laparoscopic adrenalectomy in the period from December 1995 to August 2005. The median follow up was 59 months. There was a significant decrease in both systolic blood pressure and diastolic blood pressure at final follow up compared with that before operation. Systolic blood pressure decreased from 149 mmHg to 129 mmHg at final follow up (P < 0.0001). Diastolic blood pressure decreased from 89 mmHg to 80 mmHg (P < 0.0001). Antihypertensive requirement was decreased from an average of 2.6 separate medications preoperatively to 1.4 medications at final follow up (P < 0.0001). Serum aldosterone levels were significantly lower (698 (confidence interval 534-862) pg/mL vs 181 (confidence interval 139-225) pg/mL, P < 0.0001). Overall, 34% of patients had cure of hypertension and did not require any antihypertensive agent. A further 51% had improvement in BP control, whereas 5% had no change or had worsening hypertension. Multivariate regression analysis showed that age and gland size were independent factors predicting sustained hypertension after surgery.

CONCLUSION

In appropriately selected patients with primary hyperaldosteronism, laparoscopic adrenalectomy is effective in improving long-term BP control. Larger adrenal gland size and older age at time of surgery are predictors of persisting hypertension.

Renal cysts and hypokalemia in primary aldosteronism: results of long-term follow-up after treatment

BACKGROUND

Cross-sectional studies have reported an elevated prevalence of renal cysts in patients with primary aldosteronism. The nature of this association could be related to hypokalemia and/or hypertension and has never been evaluated in prospective studies.

METHODS

A consecutive sample of 54 patients with tumoral or idiopathic primary aldosteronism was followed after adrenalectomy or treatment with aldosterone antagonists. At baseline, renal cysts were evaluated by renal ultrasound and patients with primary aldosteronism were compared with 323 essential hypertension patients with the same severity and duration of disease, and 113 age- and sex-matched normotensive subjects.

RESULTS

The adjusted prevalence and average number of renal cysts were significantly greater in patients with primary aldosteronism than in patients with essential hypertension and normotensive subjects. Multivariate analysis revealed that age and plasma potassium levels were independently associated with the presence of renal cysts in patients with primary aldosteronism. Treatment of primary aldosteronism decreased blood pressure (BP) and restored normal potassium concentrations. After a median follow-up of 6.2 years, no significant change from baseline of cyst number and cyst total volume was observed in patients with both tumoral and idiopathic aldosteronism and in a subset of 100 patients with essential hypertension. In patients with primary aldosteronism, stepwise logistic analysis showed that the presence of renal cysts was associated with worse BP outcome after treatment.

CONCLUSION

Renal cystic disease is highly frequent in patients with primary aldosteronism and either surgical or medical treatment halt its progression, supporting the contention that hypokalemia and its severity are the main contributors to cyst formation in these patients.

Relationships of plasma renin levels with renal function in patients with primary aldosteronism

BACKGROUND

The renal damage that is present in primary aldosteronism might reflect functional and potentially reversible abnormalities that are initiated by glomerular hyperfiltration. The aim of this study was to investigate the relationships of plasma renin and aldosterone concentrations with renal outcomes after treatment of primary aldosteronism.

DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS

Fifty-six consecutive patients who had primary aldosteronism and were recruited in a university center were studied. Patients were prospectively followed after either surgical or medical treatment for a mean of 6.2 yr, during which they received antihypertensive drugs to reach a target BP of <140/90 mmHg.

RESULTS

At baseline, patients with primary aldosteronism had higher creatinine clearance and albuminuria than 323 patients with essential hypertension and 113 normotensive individuals. In patients with primary aldosteronism, plasma active renin levels that were higher than the lower limit of detection (2.5 pg/ml) were associated with higher BP, plasma potassium, and albuminuria and lower creatinine clearance. Plasma aldosterone concentrations that were higher than the median value (225 pg/ml) were associated with lower plasma potassium and higher creatinine clearance. Creatinine clearance was correlated directly with plasma aldosterone and inversely with renin. During follow-up, patients with higher baseline plasma renin required use of more antihypertensive drugs to obtain BP control and had a smaller early decline in albuminuria than did patients with suppressed renin.

CONCLUSIONS

Escape of renin from suppression by excess aldosterone is associated with evidence of more severe renal damage in patients with primary aldosteronism and predicts less favorable outcomes after treatment.

Primary aldosteronism: current knowledge and controversies in Conn's syndrome

Primary aldosteronism has been recognized as a common cause of secondary hypertension, accounting for approximately 10% of the hypertensive population. Screening should be applied in hypertensive patients presenting with one of the following: hypokalemia, refractory hypertension, suggestive family history, or an incidentally detected adrenal mass. The most advocated screening test at present is the aldosterone-to-renin ratio, which has a high sensitivity but low specificity. The specificity increases if patients with low aldosterone concentrations are excluded. Published cut-off values vary depending on the hormone assay and the investigated population. Before screening, antihypertensive treatment, especially aldosterone antagonists and beta-blockers, should be discontinued. A pathologic result requires additional work up to prove mineralocorticoid excess. Subtype differentiation is performed by adrenal venous sampling combined with imaging (CT or MRI). One-third of cases are due to aldosterone-producing adenomas, for which the preferred treatment is laparoscopic adrenalectomy. Bilateral adrenal hyperplasia (idiopathic aldosteronism) underlies two-thirds of cases and requires treatment with aldosterone antagonists. Treatment is started with low doses of spironolactone (25-50 mg once daily), which often results in substantial improvements in hypertension.

Long-Term Results of Endoscopic Adrenalectomy for Conn's Syndrome

The long-term effect of adrenalectomy on aldosterone-producing adenomas of the adrenal gland is controversially discussed. The aim of this study was to analyze the long-term course, with special consideration of factors of persisting hypertension after endoscopic adrenalectomy, for Conn's syndrome. Between February 1994 and March 2004, 40 patients with Conn's syndrome underwent endoscopic adrenalectomy. Data were recorded prospectively. Adrenalectomy was carried out unilaterally in all patients. Twenty-three patients (57.5%) were women; the median age was 51.7 (31.2–71.4) years. Preoperatively, all patients presented with arterial hypertension persisting over a median period of 84 (5–240) months; 76.3 per cent of the patients had previously been treated with an aldosterone antagonist, and 85 per cent with specific antihypertensives, whereas 52.6 per cent of all patients were under therapy with potassium compounds at the time of admission. After a median follow-up of 45 (7–114) months, potassium substitution was discontinued in 100 per cent of patients, and the aldosterone antagonist was discontinued in 94.7 per cent of patients. In 60.5 per cent of patients, the specific antihypertensive drugs were reduced. Patients with a reduction in antihypertensive medication had, compared with patients without a reduction, a shorter preoperative duration of arterial hypertension and a lower level of serum aldosterone, and were younger. Endoscopic adrenalectomy for Conn's syndrome leads to an immediate normalization of the electrolyte balance postoperatively, whereas hypertension resolves in 60.5 per cent of patients in the long-term course. Thus, the coexistence of essential hypertension or, respectively, a long duration of preoperative hypertension with associated renovascular alterations are of significance for the long-term result.

Adrenal venous sampling in primary hyperaldosteronism: Comparison of radiographic with biochemical success and the clinical decision-making with “less than ideal” testing

BACKGROUND

Adrenal venous sampling (AVS) is used in the workup of primary hyperaldosteronism (PA). The purpose of this study was to determine the success rate of AVS and to examine the decision-making process after "less than ideal" AVS.

METHODS

A total of 60 patients underwent 62 AVS for PA. Biochemical evidence of adrenal vein cannulization was analyzed with adrenal-peripheral cortisol ratios. Pathology and clinical outcomes were reviewed in patients undergoing adrenalectomy.

RESULTS

Bilateral cannulization was confirmed in only 21% (pre-adrenocorticotropic hormone [ACTH] infusion) and 44% (post-ACTH infusion) AVS. Of 39 patients who underwent adrenalectomy for presumed unilateral disease, only 16 patients had "ideal" AVS, and 18 patients had only unilateral cannulization on AVS. Despite this, 11 appeared to lateralize and 7 had imaging to support unilateral disease. Postoperatively, 15 (82%) had a significant reduction in their blood pressure, and 7 (39%) of these were cured. Surgery failed in 2 patients; both were found to have bilateral hyperplasia. Bilaterally unsuccessful cannulization (n = 5) still lateralized in 3 patients, and 2 patients had nodules on computed tomography scan. All 5 patients had significant reduction in blood pressure, and 2 were cured.

CONCLUSIONS

ACTH infusion during AVS enhances the biochemical evidence of adrenal vein cannulization. Following "less than ideal" AVS, clinical decisions can still be made using anatomic and partial AVS data.

Selective use of adrenal venous sampling in the lateralization of aldosterone-producing adenomas

INTRODUCTION

It has been suggested that routine adrenal venous sampling (AVS) is necessary to lateralize an aldosterone-producing adenoma in patients with primary hyperaldosteronism. However, the success rate of AVS is variable, with potential risks. We review our experience at University of California San Francisco (UCSF), where AVS is used only selectively, to determine outcomes with this approach.

METHODS

All patients undergoing adrenalectomy for aldosteronoma at UCSF from January 1995 to October 2004 were included. Outcome after adrenalectomy was determined based on plasma levels of aldosterone and potassium, rates of persistent hypertension, and reduced use of antihypertensive medications.

RESULTS

Altogether, 65 patients were included in the study, 52 (80%) of whom had their adrenal tumors lateralized based on computed tomography scans, magnetic resonance imaging, or both. The remaining 13 (20%) patients had doubtful localization of their lesions on imaging. We did not routinely perform AVS in patients with definitive imaging findings. Thus, only 4 (8%) patients with definitive imaging findings underwent AVS, and one was unsuccessful. Of the 13 patients with doubtful lateralization on imaging, 8 underwent AVS. With this practice, biochemical cure rates after adrenalectomy were up to 100%, and hypertension resolved or was improved in 85% of patients.

CONCLUSIONS

AVS may be performed selectively only when preoperative imaging cannot definitively lateralize the aldosteronoma. This practice in our center has resulted in high cure rates. During the era of improved imaging resolution and experience, mandatory routine AVS is not necessary to achieve high cure rates for aldosteronomas.

Laparoscopic partial adrenalectomy for aldosterone-producing adenomas with needlescopic instruments

INTRODUCTION

Laparoscopic total adrenalectomy is the treatment of choice for aldosterone-producing adenomas (APAs). There have not been many reports of laparoscopic partial adrenalectomy, although this procedure offers benefits to patients with suspected bilateral APAs or an APA in a solitary adrenal gland. We describe the feasibility of a novel technique of laparoscopic partial adrenalectomy for APA solely using 2-mm working instruments and a 5 to 10-mm telescope.

TECHNICAL CONSIDERATIONS

Six unilateral and two bilateral partial adrenalectomies were performed laparoscopically. Only one umbilical 12-mm port for the telescope and two (for left adenomas) or three (for right adenomas) subcostal 2-mm working ports were used. Hemostasis and transection of adrenal tissues were performed using a 2-mm mini-bipolar coagulator and 2-mm scissors.

RESULTS

All laparoscopic operations were successfully performed using only 2-mm working instruments and a 5 or 10-mm 30 degree telescope with no intraoperative or postoperative complications. Blood loss was minimal, and the operative times were comparable to those of previous reports. All patients had low pain scores, required minimal amounts of narcotics postoperatively, and reported excellent cosmetic results for the wounds. The pathologic examinations confirmed complete excision of all adenomas with intact capsules. The plasma aldosterone concentrations and renin activities returned to normal ranges postoperatively in all patients. At a mean follow-up of 25 months (range 13 to 48), 7 (87.5%) were cured of their hypertension and 1 had the hypertensive medications significantly reduced.

CONCLUSIONS

Laparoscopic partial adrenalectomy for APAs using 2-mm working instruments and a 5 to 10-mm telescope is a safe and effective treatment alternative.

Laparoscopic adrenalectomy

Laparoscopic adrenalectomy (LA) was first described in the literature in 1992, and has become the preferred method for the removal of benign functioning and non-functioning tumors of the adrenal gland <12 cm. The objectives of the present study are to review the experience of LA gained since it was first done in 1992 and to critically evaluate its effectiveness for the surgical management of endocrine hypertension; specifically pheochromocytoma, aldosteronoma and Cushing's syndrome and disease, as opposed to open adrenalectomy. The benefits of minimally invasive techniques for the removal of the adrenal gland include decreased requirements for analgesics, improved patient satisfaction, shorter hospital stay and recovery time when compared to open surgery. LA can be performed safely for bilateral disease and may become the standard of care for malignant tumors. Current limitations are operator-dependent and not a factor of limitations of minimally invasive techniques. A thorough pre-operative work-up is key for differentiating the various cases of hypertension and adequate pre-operative treatment is paramount when indicated.

[Modern pharmacological aspects of hyperaldosteronism therapy]

The prevalence of primary hyperaldosteronism is 5-10% of all hypertensive patients, and clearly above the estimated prevalence in the past. In nearly 30% of patients with therapy resistant hypertension, primary hyperaldosteronism is detected if they are investigated thoroughly. This will result in 1.5 to 2.5 million people in Germany suffering from primary hyperaldosteronism. Besides efficient diagnostic procedures, an effective treatment is of increasing importance. The aldosterone-producing adenoma (Conn's syndrome) is primarily cured by operation, in most cases performed endoscopically. Bilateral hyperplasia, which is found in two-thirds of primary hyperaldosteronism, is treated primarily by mineralocorticoid receptor antagonist: 12.5-50 mg/day spironolactone (in case of anti-androgenic side-effects alternatively by 50-100 mg/day eplerenone). If the blood pressure can not be lowered by this first-line treatment, an additional treatment with potassium-sparing diuretics, calcium-antagonists, ACE-inhibitors or angiotensin-2-antagonists is necessary. The start of medication should be closely monitored by serum electrolyte and creatinine controls.

Primary aldosteronism: diagnostic and treatment strategies

Primary aldosteronism is caused by bilateral idiopathic hyperplasia in approximately two-thirds of cases and aldosterone-producing adenoma in one-third. Most patients with primary aldosteronism are normokalemic. In the clinical setting of normokalemic hypertension, patients who have resistant hypertension and hypertensive patients with a family history atypical for polygenic hypertension should be tested for primary aldosteronism. The ratio of plasma aldosterone concentration to plasma renin activity has been generally accepted as a first-line case-finding test. If a patient has an increased ratio, autonomous aldosterone production must be confirmed with an aldosterone suppression test. Once primary aldosteronism is confirmed, the subtype needs to be determined to guide treatment. The initial test in subtype evaluation is CT imaging of the adrenal glands. If surgical treatment is considered, adrenal vein sampling is the most accurate method for distinguishing between unilateral and bilateral adrenal aldosterone production. Optimal treatment for aldosterone-producing adenoma or unilateral hyperplasia is unilateral laparoscopic adrenalectomy. The idiopathic bilateral hyperplasia and glucocorticoid-remediable aldosteronism subtypes should be treated pharmacologically. All patients treated pharmacologically should receive a mineralocorticoid receptor antagonist, a drug type that has been shown to block the toxic effects of aldosterone on nonepithelial tissues.

Long-term follow-up after adrenalectomy for primary aldosteronism

The objective of this study was to assess the long-term effects of adrenalectomy on the blood pressure and antihypertensive medication in patients with primary aldosteronism (PA). Twenty-four patients (15 female and 9 male) with a mean age of 48.3 +/- 10.8 years underwent surgery for PA in our institution between 1988 and 2001. All subjects were re-examined with a complete clinical work-up after a mean follow-up period of 86 +/- 48 months, including blood pressure readings (<140/90 mmHg defined as normal), endocrine adrenal function, and specific medication. All patients suffered from hypertension (onset 8.5 +/- 5.5 years prior to surgery). In 92% of the patients, hypokalemia was present (onset 2.0 +/- 2.6 years prior to surgery). The histopathologic examinations revealed unilateral adenomas in 23 patients and a bilateral hyperplasia in one patient. At follow-up, 33% (8) of the patients were completely cured (normal blood pressure and no antihypertensive treatment), with seven of these eight patients being under 50 years of age at the time of surgery. One patient revealed a contralateral aldosterone-secreting adrenal adenoma during the subsequent endocrine and imaging examination 44 months after the first operation. Despite normalized plasma-aldosterone concentration (PAC), plasma-renin-activity (PRA) and serum potassium levels, a long-lasting insufficiently treated hypertension due to the delayed diagnosis in patients with PA may explain the persistent blood pressure elevation, indicating the necessity of a life-long, regular control of the blood pressure and antihypertensive medication.

Laparoscopic adrenalectomy

BACKGROUND

Laparoscopic adrenalectomy (LA) has become the procedure of choice for small benign lesions. Compared with open adrenalectomy (OA), it appears to achieve superior results in terms of recovery, cosmesis and morbidity.

METHODS

A Medline literature search (PubMed database, 1990-2003) was undertaken to identify relevant English language papers. Studies comparing LA with OA were categorized according to their level of evidence. Variables of outcome were analysed systematically for various adrenal pathologies.

RESULTS

No prospective randomized studies comparing LA with OA were identified. According to 20 comparative case-control studies (level 3b) and many case-series reports (level 4), the results of LA were reproducible and it has consistently been associated with faster recovery and lower morbidity than OA. The clinical outcome in hormonally active lesions was similar. The lateral transabdominal approach was the laparoscopic technique of choice; it was practised by 78.6 per cent of surgeons. Lesion sizes of 10-12 cm were cited as the upper limit for LA in many large series. Experience of 70 malignancies demonstrated the feasibility of LA, with short-term oncological results comparable to those of conventional surgery.

CONCLUSION

Despite a lack of a high level of evidence in its favour, LA has practically replaced OA in the management of small and medium-size benign functioning and non-functioning adrenal lesions, as it has proved to be as effective as OA with less associated morbidity. Although limited experience with large and malignant tumours shows some promise, present data are insufficient for clear conclusions to be drawn.

Outcome of patients undergoing laparoscopic adrenalectomy for primary hyperaldosteronism

OBJECTIVES

To study the long-term outcome of patients with primary hyperaldosteronism who underwent laparoscopic adrenalectomy and to determine the preoperative predictive factors of persistent hypertension.

METHODS

Between 1996 and 2002, 47 patients with primary hyperaldosteronism underwent transperitoneal laparoscopic adrenalectomy at our institution. Their clinical and biochemical parameters were reviewed retrospectively, and the outcome of 46 patients with complete follow-up notes were determined.

RESULTS

The study comprised 16 male and 30 female patients with a mean age of 45.6 years (range, 18 to 63 years). Almost all patients had hypertension and hypokalemia at presentation, requiring medication. The average operating time was 127 minutes (range, 70 to 240 min), and the mean postoperative stay was 2.6 days (range, 1 to 5 days). No mortalities occurred, and perioperative morbidity was minimal. Forty-two (91%) patients had adrenal cortical adenoma (including 1 with both adenoma and hyperplasia), and 4 (9%) had adrenal hyperplasia on histology. The average follow-up time was 21 months (range, 1 to 60 months), and at the end of follow-up, all patients had normal serum potassium levels without potassium supplements. Twenty-three (50%) patients were cured of hypertension, and 13 (28%) patients had better control of their hypertension as evidenced by the decrease in the number of antihypertensive medications used. On multivariate analysis, the age of the patient at surgery was shown to be an independent predictive factor of persistent hypertension after successful surgery.

CONCLUSION

Laparoscopic adrenalectomy is a safe and effective way to treat primary hyperaldosteronism, especially in controlling hypokalemia and in the management of hypertension. The age of a patient at surgery is an independent preoperative risk factor of persistent hypertension.

Review of surgical management of aldosterone secreting tumours of the adrenal cortex

AIMS

To evaluate the investigation and surgical management of primary hyperaldosteronism. Retrospective case note analysis of thirty-three patients who underwent adrenalectomy for primary hyperaldosteronism between 1982 and 2001 and a current relevant literature review.

METHODS

The records of twelve male and twenty-one female patients, age range 18 to 81 (mean 48 years) were reviewed. Eleven operations were performed by an open approach and twenty-two laparoscopically. Preoperative investigations included computed tomography (CT), magnetic resonance imaging (MRI), selective venous sampling and seleno-cholesterol isotope scanning, along with biochemical and hormonal assays. Twenty-six benign adenomas, three nodular hyperplastic lesions, one primary adrenal hyperplasia and three functional carcinomas were excised. Mean follow up was 12 months.

RESULTS

Patients had a mean blood pressure of 185/107 mmHg for 6.2 years mean duration. The mean severity of hypokalaemia was 2.7 mmol/l. Sensitivity of CT scanning was 85%, and of MRI 86%. Fifty percent of seleno-cholesterol scans were accurate. Mean operating time was 158 min for laparoscopic adrenalectomy whilst open surgery took 129 min (p=0.2, NS). Two cases commenced laparoscopically required open access for control of primary haemorrhage whilst one other bleed was managed via the operating ports. Mean postoperative stay was significantly shorter for the laparoscopic group (3 days compared with 7.9 days, p<0.0001). Thirty day mortality was zero. There were three infective complications in the open group (two chest, one wound) with no postoperative complications in the laparoscopic group. All patients were cured of hypokalaemia, whilst 62% cure of hypertension was achieved. Of those patients whose blood pressure was improved preoperatively by spironolactone 78% were cured by adrenalectomy. Adrenalectomy led to an overall reduction in the mean number of anti-hypertensive medications (2.3 drugs preoperative to 0.6 postoperative, p<0.0001). Of those not cured, 58% had improved blood pressure control requiring less medication on average (1.6 drugs compared with 2.6 drugs, p=0.08). Mean age of patients not cured by surgery was 55 years, whilst those cured was 44 years (p=0.03).

CONCLUSIONS

Primary hyperaldosteronism is a rare but important cause of hypertension. Selective venous sampling is a useful tool where investigations are inconclusive and fail to lateralise secretion. Patients with primary hyperaldosteronism enjoy lower complication rates and earlier discharge with the advent of laparoscopic surgery. Most patients will be cured of their hypertension and all of hypokalaemia. Laparoscopic adrenalectomy is now the accepted method of surgery for benign hyperaldosteronism. Those with bilateral disease due to idiopathic hyperaldosteronism (IHA) are not candidates for surgery and should be treated medically.

Diagnosis and management of primary aldosteronism

Identifying primary aldosteronism within the hypertensive population is an important clinical challenge, as most patients with a unilateral source of excess aldosterone secretion are amenable to surgical cure. At least 20% of patients with primary aldosteronism have normal serum potassium levels. Therefore, screening tests should not be based on recognition of hypokalemia alone. Rather, the diagnosis should depend on identifying renin suppression and measuring the ratio of plasma aldosterone concentration to plasma renin activity. The diagnosis may be confirmed by performing an aldosterone suppression test after oral salt loading. Once primary aldosteronism has been established, it is necessary to exclude glucocorticoid-remediable aldosteronism and then proceed to localization studies. Detecting a unilateral source of aldosterone, usually due to an adenoma (Conn syndrome), is achieved by postural hormonal testing and confirmed by selective venous sampling (SVS) with measurement of aldosterone concentrations (expressed as the aldosterone/cortisol ratio) in each adrenal vein. SVS is enjoying a revival in many institutions as it is more sensitive and specific than either cross-sectional imaging or scintigraphy and has the potential to influence significantly both the diagnosis and clinical decision-making. Patients with unilateral disease are ideally treated by laparoscopic adrenalectomy. Patients in whom localization is not achieved usually have bilateral adrenal hyperplasia and are treated medically.