PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Hyperaldosteronism”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2Linked to original sources

Re-evaluation of the captopril test for the diagnosis of primary hyperaldosteronism.

OBJECTIVE: We aimed to re-evaluate the captopril test in the diagnosis of primary hyperaldosteronism. DESIGN: Serum aldosterone and plasma renin activity were measured supine prior to and 60, 90, 120 minutes after oral captopril, 25 mg. PATIENTS: We have performed this test in ten patients with primary hyperaldosteronism, two with hypertension and secondary hyperaldosteronism and in ten normokalaemic patients with essential hypertension. MEASUREMENTS: Validity was assessed by mathematical prediction methods. RESULTS: Using a ratio of aldosterone to plasma renin activity greater than or equal to 1400 pmol/l per microgram/ml/h as a predictor of primary hyperaldosteronism, the captopril test had a sensitivity of 100%, a specificity of 83% and a predictive value of 82% with a 60-minute post captopril evaluation being sufficient. Nevertheless, this test was only marginally superior to a careful analysis of the supine values where a similar ratio in the presence of a normal or suppressed plasma renin activity predicted primary hyperaldosteronism with a sensitivity also of 100% but a slightly lower specificity of 75% and predictive value of 77%. CONCLUSION: Application of the captopril test to patients identified as abnormal by screening confirms all cases of primary hyperaldosteronism but false positive or equivocal results, necessitating further investigation, may occur in some patients with essential hypertension.

Adult↗

Primary hyperaldosteronism: a missed diagnosis in 'essential hypertensives'?

BACKGROUND: It has been recognised recently that primary hyperaldosteronism may be more common than previously thought, the frequency of diagnosis being improved by screening using a plasma aldosterone concentration to renin activity ratio. AIMS: To determine the frequency of primary hyperaldosteronism, screening with both plasma aldosterone to renin concentration (PRC) and activity (PRA) ratios, in normokalaemic subjects previously diagnosed as having essential hypertension. METHODS: Plasma potassium, aldosterone and PRCs and PRA and blood pressure (BP) were measured in 74 hypertensive subjects previously diagnosed by one physician as having essential hypertension. A normal range for plasma aldosterone/renin ratios was determined in 147 control subjects. Hypertensive subjects with elevated aldosterone/renin ratios were further assessed for primary hyperaldosteronism using saline loading and fludrocortisone suppression. Those in whom plasma aldosterone concentration exceeded 140 pmol/L after suppression tests underwent adrenal vein sampling for measurement of aldosterone and cortisol concentrations as well as adrenal CT scanning to diagnose the cause of primary hyperaldosteronism. The main outcome measures were a diagnosis of aldosterone producing adenoma or bilateral adrenal hyperplasia based upon adrenal vein sampling. RESULTS: Four subjects (5%) had an elevated plasma aldosterone to renin ratio using PRC and six (8%) using PRA. Two subjects (2.7%) in this selected population had primary hyperaldosteronism, both of whom had BP > 160/110 mmHg at the time of testing. CONCLUSIONS: The frequency of normokalaemic primary hyperaldosteronism appears to be greater than previously thought, though the true incidence in the general population of hypertensive subjects remains unknown. The sensitivity of diagnosis (but not specificity) may be improved by measurement of the plasma aldosterone/renin ratio and PRC is at least as adequate as PRA for this process.

Adult↗

Study on clinical and endocrine characteristics of dexamethasone-suppressible hyperaldosteronism compared with those in primary aldosteronism owing to aldosterone-producing adenoma.

The clinical and endocrine characteristics of 12 Japanese patients with dexamethasone-suppressible hyperaldosteronism were compared with those in 49 Japanese patients with primary aldosteronism due to aldosteronoma. The results were as follows: 1. Most of the laboratory data in the two groups were almost the same. 2. The grade of vascular damage in both uncontrolled (3) and well-controlled (9) patients with dexamethasone-suppressible hyperaldosteronism did not correlate with blood pressure response. 3. The responsiveness of plasma aldosterone to exogenous ACTH in 6 patients with dexamethasone-suppressible hyperaldosteronism was not different from that in 9 patients with aldosteronoma. Even in 3 well-controlled patients in the former group, the plasma aldosterone response was as low as in all the 3 patients with small aldosteronomas. 4. In 4 patients with small aldosteronomas, plasma aldosterone was continuously suppressed with daily dexamethasone to the same degree as in dexamethasone-suppressible hyperaldosteronism. 5. The blood pressure, however, did not improve even in the patients with small aldosteronomas. The possible indistinguishable mechanism in dexamethasone-suppressible hyperaldosteronism and primary aldosteronism with small adenomas and the role of unknown hypertensinogenic steroid(s) other than aldosterone in inducing hypertension in dexamethasone-suppressible hyperaldosteronism are discussed.

Adenoma↗

Normokalemic hyperaldosteronism in patients with resistant hypertension.

BACKGROUND: Primary aldosteronism is a common cause of non-renal secondary hypertension. A correct diagnosis results in curing the hypertension or targeting appropriate pharmacotherapy. In patients with low renin resistant hypertension (after treatment with three or more different anti-hypertensive drugs the blood pressure remains above 140/90 mmHg), screening for aldosteronism is mandatory. OBJECTIVES: To demonstrate that normal blood levels of potassium in resistant hypertensive patients do not exclude the possible presence of hyperaldosteronism, and to suggest the use of the plasma aldosterone concentration (ng/dl)/plasma renin activity (ng/ml/hour) ratio in screening for hyperaldosteronism. METHODS: Blood tests, suppression and stimulation tests (2 L normal saline i.v./4 hours and 20 mg furosemide i.v. for 60 minutes in a standing position) were systematically performed in 20 low renin normokalemic resistant hypertensive patients. None had renal disorders, known endocrine abnormalities or heart failure. They did not receive anti-hypertensive drugs affecting PAC or PRA. Basal PRA and PAC were measured twice: PAC after saline infusion and PAC/PRA after stimulation. RESULTS: PAC/PRA above 50 was used to denote hyperaldosteronism. Serum K was 4 +/- 0.07 mM/L, PAC 22.8 +/- 1.8 ng/dl, PRA 0.13 +/- 0.02 ng/ml/hour, PAC/PRA 190 +/- 22 (above 100 in 17). After suppression PAC decreased from 25 +/- 1.8 to 11 +/- 1 ng/dl (normal < 5 ng/dl). Stimulation did not affect PRA and PAC/PRA. Abdominal computed tomography scan revealed normal adrenal glands in 15 patients. Spironolactone (116 +/- 60 mg/day) normalized blood pressure in all patients; it was used as a single therapy in 8, and in association with only one anti-hypertensive drug in the remaining 12 patients. In one patient the treatment was discontinued due to the presence of hyperkalemia. CONCLUSIONS: Low renin resistant hypertension associated with normokalemia may be due to hyperaldosteronism. Normal aldosterone levels in the basal condition do not exclude the possibility of hyperaldosteronism. Using a PAC/PRA ratio above 50 as a screening test can aid the physician in deciding when to perform dynamic tests, thus increasing the sensitivity of the diagnosis of hyperaldosteronism. CT scan is frequently normal. Targeted pharmacotherapy leads to a normalization of blood values.

Adult↗

[High prevalence of thyroid disfunction in primary hyperaldosteronism].

Primary hyperaldosteronism is associated with other endocrinology pathologies, like pheochromocytoma, Cushing's syndrome, hyperprolactinemia, primary hyperparathyroidism and a type of multiple endocrine neoplasia. Furthermore, association between hyperaldosteronism and thyroid diseases were already pointed out. Aim of the study was to value the prevalence of some thyroid diseases in a series of patients with primary hyperaldosteronism. We studied 105 consecutive patients with primary hyperaldosteronism, 43 (40.95%) with adrenal adenoma, 62 (50.05%) with bilateral adrenal hyperplasia and a control group of 223 patients with essential arterial hypertension. In all patients we tested thyroid function (FT3, FT4, TSH), thyroid antibodies (AbTPO, AbTG) and, sometimes, thyroid morphology by ultrasonography (US scan). The results of the study show that thyroid disfunction occur in 28.6% of patients with primary hyperaldosteronism and in 16.6% of patients with essential hypertension, with a statistically significative difference (chi2 = 0.012). At present, the relationship between primary hyperaldosteronism and thyroid diseases is unclear, but it can be hypothesized that there are common pathogenetic mechanisms, like an imbalance between various growth factors. Further studies are necessary to confirm the results of our study.

Adult↗

[Hyperaldosteronism sensitive to dexamethasone with adrenal adenoma. Clinical, biological and genetic study].

OBJECTIVES: Dexamethasone-sensitive hyperaldosteronism is associated with early onset hypertension and primary hyperaldosteronism. Diagnosis is difficult but can be improved by genetic testing for the mutant gene. METHODS: We collected the clinical, biological and genetic elements observed in a family with dexamethasone-sensible hyperaldosteronism. Complete data were obtained in 5 adult subjects with the disease. Degree of hypertension varied, more so in the second generations as did hypokaliaemia and hyperaldosteronism. In affected patients, there was a 10 to 50 fold increase in urinary 18-OH components and 18 oxocortisol. RESULTS: Single dose (1.5 mg) dexamethasone led to a greater than 80% drop in aldosterone levels in the blood and urine, confirming the abnormal effect of ACTH on mineralocorticoid secretion. At the dose of 1 mg/d for 10 weeks, dexamethasone lowered mean 24-H ambulatory arterial pressure (11.8/9.6 mmHg) and corrected for the hypokaliaemia (+0.54 mmol/l) and the hyperaldosteronism (mean decrease -36% and -75% in blood and urine respectively). An adrenal tumour was identified in hyperplasic glands in two subjects and a micronodular formation was identified in two others. The specific molecular diagnosis of the disease was done with Southern blotting. Among the 18 families in 3 generations, 8 carried a 11 beta OHase-aldosterone synthetase chimeric gene. This mutation cosegregates with hormonal abnormalities and confirms the autosomal dominant inheritance of the disease. CONCLUSION: The simplicity and rapidity of genetic testing allows early diagnosis of this disease among families with early onset hypertension and associated hyperaldosteronism with or without adrenal hyperplasia and/or a tumoral formation.

Adolescent↗

Glucocorticoid-suppressible hyperaldosteronism: effects of crossover site and parental origin of chimaeric gene on phenotypic expression.

1. Genetic analysis of five kindreds with glucocorticoid-suppressible hyperaldosteronism, four of whom had not been subjected to any previous genetic analysis, revealed three different crossover breakpoints within the five kindreds clustered in the exon 3-intron 4 region of the chimaeric gene. The site of the crossover point had no effect on blood pressure within the kindreds studied. 2. The gene causing glucocorticoid-suppressible hyperaldosteronism was in strong linkage disequilibrium with an allele of a newly described restriction enzyme polymorphism of the aldosterone synthase gene promoter region, suggesting a possible role for this allele in the development of the chimaeric gene. 3. A novel observation on subjects inheriting glucocorticoid-suppressible hyperaldosteronism from their mothers showed that they had significantly higher plasma aldosterone concentrations and mean arterial blood pressures than those inheriting glucocorticoid-suppressible hyperaldosteronism from their fathers. 4. These results raise the possibility that chronic exposure in utero to elevated plasma aldosterone concentrations may result in the permanent programming of mineralocorticoid-dependent blood pressure regulatory mechanisms, which is amplified in later life by the elevated plasma aldosterone concentrations found in glucocorticoid-suppressible hyperaldosteronism.

Adolescent↗

Surgical treatment of primary hyperaldosteronism.

OBJECTIVE: A retrospective review of patients with primary hyperaldosteronism treated at the Duke University Medical Center was performed. SUMMARY BACKGROUND DATA: The management of patients with primary hyperaldosteronism has changed dramatically in the past 20 years. The outcome of surgical treatment was examined to optimize the management of these patients. METHODS: All patients who were evaluated for primary hyperaldosteronism before operation and who had adrenal surgery at Duke University Medical Center from 1970 to 1993 were included in the study. RESULTS: A ratio of plasma aldosterone concentration to plasma renin activity greater than 250 was predictive of hyperaldosteronism in 94% of patients. This ratio also predicted the size of the adenoma. Surgical treatment cured hypokalemia in 90% of the patients. Hypertension was cured or greatly improved, with an average decrease of 50.4 mmHg and 25.2 mmHg for systolic and diastolic pressures, respectively. Patients who had hypertension for less than 5 years achieved a satisfactory blood pressure response more often (13 of 14 patients) than did patients who had hypertension for 5 or more years (15 of 20 patients). CONCLUSIONS: Preoperative evaluation of patients with primary hyperaldosteronism using current modes allows a posterior approach to be used in most patients. Adrenalectomy cures hypokalemia and hypertension; however, patients with a history of hypertension for less than 5 years may be more likely to be cured by adrenal resection.

Adenoma↗

Circadian blood pressure variation in hypertensive patients with primary hyperaldosteronism.

A less-than-normal decline in nocturnal blood pressure (BP) has been associated with excessive hypertensive complications. This is concerning because secondary hypertension is often associated with this so-called nondipper BP profile. A nondipping pattern is more frequently found in the presence of pheochromocytoma, Cushing's syndrome, and sleep apnea syndrome, but the prevalence is unclear in patients with primary hyperaldosteronism. We therefore studied ambulatory BP profiles in 16 hypertensive patients with primary hyperaldosteronism and an equal number of essential hypertensive subjects. The awake-sleep BP difference of the hyperaldosteronism patients was similar to that of essential hypertensives (15/14 +/- 3/2 versus 14/9 +/- 3/2 mm Hg, P=NS). The prevalence of dippers and nondippers (according to two distinct criteria) in the two groups was similar. Repeat ambulatory BP monitoring in 12 subjects with primary hyperaldosteronism after specific intervention (3 after surgical removal of an adrenal adenoma and 9 after commencement and titration of spironolactone therapy) showed highly significant reductions in office BP (22/10 +/- 6/4 mm Hg, P<.05) and awake and sleep BP. However, the extent of nocturnal BP decline was unchanged between the two studies (17/16 +/- 3/3 versus 16/12 +/- 2/2 mm Hg, P=NS). There was no correlation between the awake-sleep difference and serum or urinary aldosterone levels or the aldosterone-to-renin ratio. In this study, we did not detect any differences in the awake-sleep differences between a group of hypertensives with primary hyperaldosteronism and a control group of essential hypertensives.

Adult↗

Diagnosis under random conditions of all disorders of the renin-angiotensin-aldosterone axis, including primary hyperaldosteronism.

Theoretically, the relationship between plasma aldosterone (PA) and PRA in normal subjects under random conditions should differ from that in patients with primary hyperaldosteronism or primary adrenal failure, but should be similar to that in patients with secondary hyperaldosteronism or hyporeninemic hypoaldosteronism. PA, expressed as a function of PRA, the PA/PRA ratio, provides an index of adrenal sensitivity in normal subjects under routine conditions. The random PA/PRA ratios in patients with primary adrenal disorders did not overlap with those in normal subjects, patients with secondary adrenal disorders, hypertensive subjects, or other patients. A single elevated PA/PRA ratio, i.e. more than 920, associated with elevated PA in 4 patients or normal PA in 6 patients indicated primary hyperaldosteronism in 10 patients. However, 5 of 17 patients with chronic renal failure had elevated PA/PRA ratios, but did not have primary hyperaldosteronism. All 14 patients with secondary hyperaldosteronism had elevated PA associated with normal PA/PRA ratios. A single PA/PRA ratio of less than 28 associated with low PA in 18 patients and a normal PA in 1 patient indicated primary adrenal insufficiency, while a low PA associated with a normal PA/PRA ratio indicated hyporeninemic hypoaldosteronism in 7 patients. Fifty-nine patients with nonadrenal disorders other than renal failure had normal PA and PA/PRA ratios. Therefore, with the exception of patients with advanced renal failure, only a single blood sample is required to establish all diagnoses of disorders of the renin-angiotensin-aldosterone axis under random conditions.

Biomarkers↗

Diagnosis of primary hyperaldosteronism: importance of correlating CT findings with endocrinologic studies.

Twenty patients with primary hyperaldosteronism had endocrinologic and radiologic studies to distinguish aldosterone-producing adenoma from idiopathic hyperaldosteronism due to bilateral micro- or macronodular hyperplasia of the adrenal cortex. In addition to examination for changes in the plasma level of aldosterone associated with postural changes and measurement of the plasma level of 18-hydroxycorticosterone, all 20 patients had CT examination of the adrenal glands. In three patients with normal adrenal glands on CT and three patients with CT evidence of two solitary nodules, one in each adrenal gland, a diagnosis of idiopathic hyperaldosteronism was confirmed by endocrinologic findings (five patients) or 131I-6 beta-iodomethyl-19-norcholesterol (NP-59) adrenal scintigraphy (one patient). In nine patients with a solitary adrenal nodule on CT, a diagnosis of aldosterone-producing adenoma was confirmed by surgery (seven patients) or hormone sampling via the adrenal veins (two patients). However, in three patients with a solitary adrenal nodule on CT, a diagnosis of idiopathic hyperaldosteronism was suggested by endocrinologic findings (three patients) and confirmed by the results of NP-59 scintigraphy (two patients) or adrenal venous sampling (one patient). In addition, in two patients with CT evidence of three adrenal nodules (two in one gland, one in contralateral gland), a diagnosis of aldosterone-producing adenoma was suggested by endocrinologic findings in both patients and confirmed by surgery in one. Although high-resolution CT is highly accurate for the detection of aldosterone-producing adenoma, significant diagnostic errors can occur in patients with primary hyperaldosteronism if CT findings are not correlated with results of endocrinologic studies.

18-Hydroxycorticosterone↗

Laparoscopic adrenalectomy is superior to an open approach to treat primary hyperaldosteronism.

We reviewed our institutional experience with primary hyperaldosteronism to compare clinical outcomes after laparoscopic versus open adrenalectomy. All patients surgically treated for primary hyperaldosteronism from 1988 through 1999 are included in this study. Patients were assigned to either the LA (laparoscopic) or OA (open) group depending on the initial surgical approach selected for treatment. Records were reviewed to determine demographics, operative results, and complications. Twenty-four patients were surgically treated for primary hyperaldosteronism. There were no significant differences between groups with respect to age, weight, number of preoperative antihypertensive medications, or preoperative potassium level. The results of adrenalectomy with respect to number of postoperative antihypertensive medications or serum potassium level were also similar. Operative times were not significantly different (191 +/- 53 minutes for OA and 205 +/- 88 minutes for LA) between groups, but four LA patients were converted to OA. Estimated blood loss was 401 +/- 513 cm3 for OA and 127 +/- 131 cm3 for LA (P = 0.07). Hospital length of stay was 6.7 +/- 3.7 days for OA and 3.3 +/- 2.7 days for LA (P = 0.02). Complications were nine for OA and three for LA (P = 0.001 by Pearson's Chi square). LA is similar to OA in the treatment of primary hyperaldosteronism. The significantly fewer complications and shorter length of hospital stay associated with LA makes the laparoscopic approach the preferred method for treating primary hyperaldosteronism.

Adrenalectomy↗

[Familial hyperaldosteronism].

Primary aldosteronism is a disorder characterized by hypertension and hypokalemia due to aldosterone secretion out of renin-angiotensin control. It is generally caused by aldosterone-producing adenoma or adrenocortical hyperplasia but, in some cases, it is due to genetic alterations. Familial type I hyperaldosteronism is the result of anomalous regulation of aldosterone secretion from ACTH (which normally regulates cortisol synthesis). Aldosterone hypersecretion can be suppressed by exogenous glucocortcoids such as dexamethasone. This autosomal dominant disorder is caused by unequal cross-over between two genes with wide sequence homology: CYP11B1 and CYP11B2. The hybrid gene is the product of fusion between the ACTH-responsive regulatory portion of the 11b-hydroxylase gene (CYP11B1) and the coding region of the aldosterone synthase gene (CYP11B2). Familial type I hyperaldosteronism is a disease with incomplete penetration and variable expressivity, especially in relation to hypertension. The marked variability in hypertension severity can mirror an interaction between the hybrid gene and other hereditary factors involved in the regulation of blood pressure. Familial type II hyperaldosteronism is another autosomal dominant form of hyperaldosteronism due to aldosterone hyper-secretion not suppressible by dexamethasone. This disorder is unrelated to mutation of the hybrid gene. The genetic cause of type II hyperaldosteronism is presently unknown, but a genome-wide search has revealed that the disorder is linked with a locus on chromosome 7 in a region that corresponds to cytogenetic band 7p22.

Humans↗

Clinical, biochemical and genetic approaches to the detection of familial hyperaldosteronism type I.

AIM: Since detection of familial hyperaldosteronism type I (glucocorticoid-suppressible hyperaldosteronism) allows specific treatment of hypertension with dexamethasone, we compared clinical, biochemical and genetic approaches to detection. PATIENTS AND METHODS: We studied 22 affected patients, 21 from a single, large family and an additional adopted male. Plasma aldosterone, plasma renin activity and urinary 18-oxo-cortisol were measured by radioimmunoassay. The hybrid gene was demonstrated using either Southern blotting or a long polymerase chain reaction technique. RESULTS: Thirteen out of 22 (59%) patients with familial hyperaldosteronism type I, but only four out of 12 (33%) under 20 years of age, were hypertensive. Plasma potassium and aldosterone were each normal in 20 out of 22 (91%), and unhelpful in diagnosis. Plasma renin activity, the aldosterone: plasma renin activity ratio and 18-oxo-cortisol were more sensitive, being abnormal in 20 out of 22 (91%), 19 out of 22 (86%) and 20 out of 20 (100%) patients, respectively. Aldosterone was unresponsive (<50% rise) to 2 h of upright posture following overnight recumbency in 15 out of 15 (100%) patients studied, and to angiotensin II infusion (2 ng/kg per min for 1 h) in 14 out of 14 patients (100%). Whereas all the abovementioned abnormalities are also characteristic of angiotensin II-unresponsive aldosterone-producing adenoma, marked aldosterone suppression following 4 days of dexamethasone (0.5 mg every 6 h) was sensitive and specific for familial hyperaldosteronism type I (n = 11). The hybrid gene was detectable in peripheral blood leucocyte DNA in all 22 affected patients by Southern blotting, and by a faster, long polymerase chain reaction method developed in our laboratory, both methods requiring only a single blood collection. CONCLUSIONS: Should studies in other families confirm its universal applicability, long polymerase chain reaction should prove to be the most practical means of detecting familial hyperaldosteronism type I in laboratories equipped with this technique.

Adolescent↗

[The effect of insulin in primary hyperaldosteronism].

BACKGROUND: Deteriorated insulin resistance was described in patients with essential hypertension. The objective of the present study was to test at the receptor and postreceptor level the presence of insulin resistance in hypertension with primary hyperaldosteronism. METHODS AND RESULTS: The diagnosis of primary hyperaldosteronism was assessed by means of biochemical and imaging methods in 123 hypertensive patients with a normal glucose tolerance (mean age 49.8 +/- 12.9 years, range 20-65 years, BMI 28.3 +/- 4.8 kg/m2). The blood pressure was monitored for 24 hours by a Spacelab tonometer (systolic BP 168 +/- 21 mm Hg, diastolic BP 103 +/- 9 mm Hg, plasma aldosterone in a recumbent position 426 +/- 472 pg/ml (normal values under 150 pg/ml), concentration of serum potassium 3.6 +/- 0.6 mmol/l. The control group was formed by seven volunteers matched for age and BMI. The patients had a normal basal blood sugar level in the morning (5.0 +/- 0.6 mmol/l), the basal insulinaemia was 19.5 +/- 10.2 mU/l. The insulin resistance was examined using the method of an euglycaemic hyperinsulinaemic clamp on Biostator at an insulin infusion rate of 1 mU/kg/min. Concurrently insulin receptors on red blood cells were assessed. The plasma potassium concentration was maintained by means of insulin receptors on erythrocytes. The potassium plasma concentration was maintained by means of a linear dosage device with potassium at constant physiological levels (after previous supplementation). In patients with primary hyperaldosteronism the authors observed, as compared with healthy controls, a lower glucose consumption during the clamping (glucose disposal rate 18.7 +/- 4.8 vs 29.3 +/- 3.7 mumol/kg/min, p < 0.01), a rise of the metabolic glucose clearance (3.8 +/- 1.5 vs. 7.0 +/- 1.1 ml/kg/min, p < 0.01 and an index of tissue sensitivity for insulin) 23.7 +/- 9.8 vs. 37.5 +/- 11.6 mumol/kg/min per mU/l x 100, p < 0.02). The characteristics of insulin receptors in patients with primary hyperaldosteronism did not differ from normal values. No correlation was found between the plasma concentration of aldosterone and the index of tissue sensitivity for insulin (r = 0.011, NS). CONCLUSIONS: It may be stated that primary hyperaldosteronism is associated with insulin resistance at the postreceptor level. Its pathogenesis has not been elucidated so far and will be the object of future research.

Adult↗

Laparoscopic vs open adrenalectomy for the treatment of primary hyperaldosteronism.

HYPOTHESIS: That the clinical presentations, biochemical profiles, and surgical outcomes of patients treated with laparoscopic vs open adrenalectomy for primary hyperaldosteronism are different. DESIGN, SETTINGS, PATIENTS, AND INTERVENTIONS: The medical records of 80 patients with primary hyperaldosteronism who underwent open adrenalectomy between 1975 and 1986 or laparoscopic adrenalectomy between 1993 and 1998 at the University of California-San Francisco were reviewed by a single unblinded researcher (W.T.S.). MAIN OUTCOME MEASURES: Severity of hypertension and hypokalemia at diagnosis, their improvement after adrenalectomy, and operative complications. RESULTS: Thirty-eight patients underwent open adrenalectomy and 42 patients underwent laparoscopic adrenalectomy. The patients who underwent open adrenalectomy had documented hypertension for a median of 5 years before surgery; all had diastolic blood pressures greater than 100 mm Hg. Laparoscopically treated patients had documented hypertension for a median of 2.5 years preoperatively, and 20 (48%) had diastolic blood pressures greater than 100 mm Hg. The median preoperative serum potassium levels for the open and laparoscopic groups were 2.6 mmol/L and 3.3 mmol/L, respectively; the mean serum aldosterone levels were 1.47 nmol/L and 1.30 nmol/L. Thirty-two (84%) of the 38 patients who underwent open surgery and 41 (98%) of the 42 patients treated laparoscopically had adrenal adenomas. The sensitivity of preoperative computed tomographic scanning for adenomas was 83% for the patients treated with open adrenalectomy and 93% for those treated laparoscopically. There were 4 postoperative complications in the open surgery group and none in the laparoscopic group. Postoperatively, 30(81%) of 37 patients (excluding 1 patient who died of adrenocortical carcinoma) in the open surgery group and 37 (88%) of 42 patients treated laparoscopically were normotensive. Post-operative values were 3.6 to 5.0 of serum potassium per liter and 3.5 to 4.9 of serum potassium per liter in the open and laparoscopic groups, respectively. CONCLUSIONS: Patients who are treated with laparoscopic adrenalectomy for primary hyperaldosteronism are being referred with less severe hypertension and hypokalemia than patients formerly treated with open adrenalectomy. Patients treated laparoscopically had fewer postoperative complications and were equally likely to improve in blood pressure and hypokalemia. Laparoscopic adrenalectomy has become the treatment of choice for patients with primary hyperaldosteronism because of lower morbidity.

Adrenalectomy↗

The effect of amiloride on the renin-aldosterone system in primary hyperaldosteronism and Bartter's syndrome.

Amiloride is a potassium-sparing diuretic which has been advocated for the treatment of hypokalemic disorders. This agent was prospectively evaluated in hypokalemic patients with either primary hyperaldosteronism (ten patients) or Bartter's syndrome (five patients). Vital signs, electrolytes, and ambulatory hormonal studies were assessed during a control period and treatment period with amiloride therapy at 10 to 40 mg/day over two to 24 weeks. During the treatment period the systolic and diastolic blood pressure fell significantly in primary hyperaldosteronism but remained unchanged in Bartter's syndrome. In summary, amiloride therapy (1) increased plasma potassium in both diseases; (2) increased plasma renin activity (PRA) in primary hyperaldosteronism but decreased PRA in Bartter's syndrome; and (3) increased plasma aldosterone in both diseases. Since potassium is known to suppress renin production and stimulate aldosterone secretion, correction of the hypokalemia in this study probably accounts for the decreased PRA and increased plasma aldosterone observed in Bartter's syndrome. The increase in both PRA and plasma aldosterone in primary hyperaldosteronism, however, may be evidence of either a direct activation of the renin-aldosterone system or, alternatively, may be due to the mild natriuretic effects of amiloride.

Adult↗

Anti-aldosterone treatment and the prevention of myocardial fibrosis in primary and secondary hyperaldosteronism.

In arterial hypertension associated with primary or secondary hyperaldosteronism myocardial fibrosis is an important determinant of pathologic hypertrophy. To further examine the relationship between elevations in plasma aldosterone (ALDO) and myocardial fibrosis, we analysed perivascular collagen area (PVCA) and interstitial collagen volume fraction (CVF) by videodensitometry and hydroxyproline concentration (HPro) by high-performance liquid chromatography. We examined both the left (LV) and right (RV) ventricles in the following rats models of primary or secondary hyperaldosteronism of eight weeks duration: unilateral renal ischemia (RHT); continuous ALDO administration via osmotic minipumps (0.75 microgram/h s.c.) and enhanced dietary sodium following uninephrectomy (AL); in RHT and AL after pre- and continuous treatment with either 20 (S) or 200 (SS) mg/kg/day s.c. of the aldosterone receptor antagonist, spironolactone; in AL after pre- and continuous treatment with 50 mg/kg/day oral captopril (AL + CAP); as well as in age and sex matched controls (C). Systolic arterial pressure was comparably elevated in RHT and AL (202 +/- 12 and 193 +/- 7 mmHg, respectively; P < 0.0005 vs C); it remained elevated with low dose spironolactone in either model of arterial hypertension, but was normalized with high dose spironolactone or captopril in AL. Left ventricular hypertrophy (LVH), expressed as significantly elevated LV/RV weight or LV/BW ratios, was present in all experimental groups, excluding AL + SS and AL + CAP, when compared with C (P < 0.005). In each ventricle, CVF and PVCA were increased (P < 0.005) in either model of hypertension and in AL + CAP, but were no different from C in all groups receiving either dose of spironolactone. Similar findings were observed for HPro. Thus, myocardial fibrosis was comparable in primary or secondary hyperaldosteronism, wherein elevations in plasma aldosterone, relative to increased sodium intake, are associated with arterial hypertension. The competitive ALDO receptor antagonist, spironolactone, was able to prevent fibrosis in either model irrespective of the development of LVH and the presence of hypertension. Captopril prevented hypertension and LVH, but not unexpectedly it did not prevent myocardial fibrosis in primary hyperaldosteronism. These findings provide further evidence that in these rat models increased plasma ALDO, relative to dietary sodium, plays a major role in the adverse accumulation of collagen that appears in the myocardium.

Angiotensin II↗