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Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Primary aldosteronism is classified as aldosterone-producing adenoma (APA), idiopathic hyperaldosteronism (IHA), unilateral adrenal hyperplasia (UAH), primary adrenal hyperplasia (PAH), adrenal cancer, and glucocorticoid-remediable aldosteronism. We describe here 4 cases of primary aldosteronism due to unilateral hyperaldosteronemia, demonstrating unique histopathologic findings, such as unilateral multiple adrenocortical micronodules in the affected adrenals. Thirty-three patients with primary aldosteronism were consecutively admitted; 27 of them were treated by unilateral adrenalectomy. Four of them also had unilateral adrenal hypersecretion of aldosterone by selective adrenal venous sampling and adrenocortical multiple micronodules without an adenoma. These patients had hyporeninemic hyperaldosteronism with normokalemic hypertension. In these patients, furosemide plus upright test failed to increase plasma renin activity (PRA); the ratio of plasma aldosterone concentration (PAC) to PRA at 90 minutes after captopril administration was similar to that in patients with IHA and APA. Aldosterone concentrations were increased in each unilateral adrenal vein, and poorly encapsulated multiple adrenocortical micronodules from 2 to 3 mm in diameter were microscopically detected in the resected adrenal glands. Immunohistochemical analysis of steroidogenic enzymes, including cholesterol side chain cleavage, 3beta-hydroxysteroid dehydrogenase, 21-hydroxylase, 17alpha-hydroxylase, and 11beta-hydroxylase, indicated that the cortical cells within these micronodules were active in aldosterone production, while the non-nodular zona glomerulosa cells were inactive. We conclude that the clinical and pathologic characteristics of our 4 cases with unilateral multiple adrenocortical micronodules (UMN) are distinct from those of APA, IHA, UAH, and PAH. Furthermore, unilateral hyperaldosteronemia induced by UMN may be frequently misdiagnosed, because standard imaging tests, which cannot always detect tiny abnormalities of adrenals, showed "normal adrenal glands" in these patients. Thus, primary aldosteronism due to UMN should be carefully examined for differential diagnosis of each form of hyperaldosteronemia.
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PMID:Unique cases of unilateral hyperaldosteronemia due to multiple adrenocortical micronodules, which can only be detected by selective adrenal venous sampling. 1188 72

Primary aldosteronism is a potentially curable form of hypertension. Recent studies using the plasma aldosterone to plasma renin activity ratio as screening test in hypertensive populations have demonstrated a high prevalence of primary aldosteronism close to 10%. This frequency is clearly higher than the classically described when hypokalemia is used as the screening method. The most common subtypes of primary aldosteronism are idiopathic aldosteronism and aldosterone-producing adenoma. Other causes are glucocorticoid-remediable aldosteronism, unilateral or primary adrenal hyperplasia and adrenal carcinoma. The diagnosis of primary aldosteronism is advocated to confirm the autonomy of aldosterone secretion from the renin-angiotensin system and to differentiate the clinical subtypes of the disease. This article reviews the new data about prevalence, diagnosis criteria and describes the clinical, biochemical and genetic characteristics of the different subtypes of the disease. We also discuss the treatment, and the differential diagnosis with other hyper-mineralocorticoid states.
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PMID:Primary aldosteronism. 1193 20

This report describes a rare case of ACTH-independent macronodular adrenal hyperplasia (AIMAH) arisen with symptomatic severe hypertension and hypokaliemia. A 55-year-old man was admitted to hospital with a clinical picture characterized by several episodes of transient ischemic attacks (TIA) and right hemiplegia, related to severe arterial hypertension. Laboratory tests showed urinary levels of catecholamines, metanephrines and vanillylmandelic acid (VMA) in normal range; high urinary free cortisol excretion, elevated serum cortisol with loss of the circadian rhythm and low ACTH plasma levels. ACTH failed to respond to CRH administration. Serum cortisol levels were not modified after high doses of dexamethasone. MRI showed bilateral macronodular hyperplasia of adrenal glands, whereas pituitary-MRI did not show tumoral lesions. Therefore, ACTH-independent macronodular hyperplasia was suspected. Though obese, the patient had no typical Cushing habit, and symptomatic hypertension with hypokaliemia was the only clinical evidence for this rare kind of Cushing's syndrome. After obtaining a satisfactory control of blood pressure, the patient was successfully submitted to laparoscopic bilateral adrenalectomy and underwent complete clinical remission. The histology showed adrenal macronodular hyperplasia. During the twenty-four month follow-up, the patient had no further transient ischemic attacks or need of glucocorticoid replacement therapy and withdrew the antihypertensive drugs.
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PMID:A case of severe hypertension caused by ACTH-independent macronodular adrenal hyperplasia. 1193 69

Primary aldosteronism is a disorder with hypertension, hypokalemia, increased plasma aldosterone, and suppressed renin activity. A random plasma aldosterone/renin activity (PA/PRA) >65 (conventional units ratio [CUR] >30) has been proposed as a screening test. We have retrospectively determined the value of the post-captopril plasma aldosterone/renin activity (CAPT PA/PRA) test for the diagnosis of patients with primary aldosteronism whose PA/PRA was <65. We considered the CAPT PA/PRA test to be positive for primary aldosteronism if either the plasma aldosterone concentration did not drop below 0.33 nmol/L (12 ng/dL) or the ratio was >26 (CUR >12). We found 6 patients with a random PA/PRA of 21 to 60 (CUR 10 to 28), yet with an abnormal post-captopril test criteria for primary aldosteronism. Five had an abnormal saline suppression test, and all 6 were confirmed by a combination of diagnostic localization with computerized axial tomography, iodocholesterol scan, adrenal venous sampling, and/or surgery. Four had idiopathic adrenal hyperplasia, and 2 had an aldosterone-producing adenoma. One other patient had an abnormal random plasma aldosterone/renin activity ratio of 99 (CUR 46), a negative saline infusion study, and was determined to have essential hypertension. In summary, the CAPT PA/PRA, but not the random PA/PRA, correctly diagnosed 6 patients with primary aldosteronism in our institution. An additional patient with essential hypertension was incorrectly diagnosed as having primary aldosteronism by the PA/PRA test. We conclude that the simple addition of 25 mg of captopril, taken orally 2 hours before sampling, enhances the accuracy for diagnosing patients with primary aldosteronism.
Hypertension 2002 Apr
PMID:Diagnostic value of the post-captopril test in primary aldosteronism. 1196 53

Primary aldosteronism is a disorder that is commonly considered in patients referred to the hypertension clinic. The ease of measuring the random aldosterone-to-renin ratio in conjunction with an elevated serum aldosterone level has led to an increased screening for this disorder. Typically, patients undergo a confirmatory test after a positive screening test. However, once primary aldosteronism is confirmed, subtype delineation is critical to decide on the optimal treatment. We report a patient with resistant hypertension and primary aldosteronism with a normal computed tomographic scan of the adrenal glands, a left-sided uptake on adrenal scintigraphy, and a right-sided lateralization of aldosterone after adrenal vein sampling. A repeat adrenal vein sampling confirmed the aldosterone lateralization to the right adrenal gland, which was then removed laparoscopically. The patient had a good clinical and biochemical response, and unilateral adrenal hyperplasia was discovered at histology. Excessive reliance on adrenal scintigraphy without adrenal vein sampling may lead to serious errors in patient management.
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PMID:Unilateral adrenal hyperplasia causing primary aldosteronism: limitations of I-131 norcholesterol scanning. 1202 49

Aldosteronoma is a surgically curable cause of hypertension. Recent studies have found aldosteronomas to be a more common cause of hypertension than previously thought. At least 2% of patients with hypertension may have an aldosteronoma. More than 50% of these patients are normokalemic because of earlier diagnosis or milder disease, but still benefit from adrenalectomy. Patients with hypertension should be screened for possible primary hyperaldosteronism regardless of their serum potassium level. When used in conjunction with the appropriate laboratory tests, high-resolution computerized tomography scanning helps the surgeon to differentiate accurately between an adrenal adenoma and bilateral adrenal hyperplasia. Focused approach and laparoscopic resection are the norm for the surgical treatment of aldosteronoma.
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PMID:Aldosteronoma. 1207 69

Pheochromocytoma and primary hyperaldosteronism are well-known causes of hypertension. It was recently reported that their frequency in the hypertensive population is 0.1-0.2% and 3-15%, respectively. We describe the case study of a patient with severe hypertension (200/100 mmHg) and the coexistence of pheochromocytoma and primary hyperaldosteronism attributable to adrenal hyperplasia. The originality of this clinical report is that the patient presented a pheochromocytoma in the left adrenal gland and hyperplasia of the contralateral adrenal gland. The simultaneous presence of pheochromocytoma and primary hyperaldosteronism in the same patient is probably due to either genetic predisposition or to specific environmental risk factors for these adrenal diseases.
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PMID:[Hyperaldosteronism and simultaneous pheocromocytoma: a puzzle case]. 1219 18

Primary hyperaldosteronism represents less tha 1% of all causes of hypertension. We report one case of primary hyperaldosteronism which emphasizes the difficulty of distinguishing tumoral PHA from idiopathic PHA (bilateral adrenal hyperplasia), observed in a 57-year-old man. The diagnosis was suggested by marked hypokalemia, and was confirmed by hyperaldosteronaemia and low and poorly stimulated renin activity. Intravenous saline infusion failed to significantly suppress plasma aldosterone levels. Upright posture for 60 minutes suppressed plasma aldosterone concentration. A Computed tomography (CT) scan showed bilateral adrenal mass. Management consisted of total right adrenalectomy, and enucleation of adenoma from the opposite adenoma. The patient is normotensive 4 years after surgery.
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PMID:[Bilateral Conn's adenoma. Diagnostic discussions]. 1246 32

Excess secretion of any of the adrenal cortical or medullary hormones contributes to a number of well-known clinical syndromes.. They may result from benign or malignant adrenal tumours, adrenal hyperplasia or, least frequently, from extra-adrenal disease. Differentiation among these possibilities is often impossible on clinical or biochemical grounds alone. Location of the site(s) of excess hormone production in the past depended on relatively insensitive or invasive radiological methods. The non-invasive evaluation began with X-ray computed tomography but the functional significance of anatomical abnormalities cannot be determined from CT scan. Incorporation of specific radiopharmaceuticals into the abnormal tissues allows scintigraphic localization of functional abnormalities with a high degree of efficacy. The combination of adrenal scintigraphy and kompjuterizovanom tomografijom CT or magnetskom rezonancijom MRI should in most cases obviatc the need for more invasive procedures. Phaeochromocytoma is rare in hypertensive population, affecting only an estimated of 0.1%. However, a high index of suspicion is essential, since these tumours have potentially life-threatening cardiovascular effects and their successful resection is curative. Important clinical clues include the presence of orthostatic hypotension in an untreated hypertensive, resistance of hypertension to standard therapy (including possible exacerbation by (beta-blockers). In most cases, the diagnosis can be established by demonstrating high levels of free catecholamines and their metabolites (metanephrines and Vanillylmandelic acid). Clonidine test may be important in some cases. The purpose of this study is to point that metaiodobenzylguanidine (mlBG) has proved to be a safe, sensitive and highly specific agent for the location of phaeochromocytoma. The first successful schinigraphic demonstration of phaeochromocytomas in man was reported in 1981, using a new radiopharmaceutical, 131l-metaiodobenzylguanidinc (mlBG). mlBG is an aralkyl-guanidine which structurally resembles noradrenaline sufficiently to be recognized and be stored in the catecholamine storage vesicles. Whereas unstored noradrenaline is rapidly degraded, the halogenated benzyl ring of mlBG conlers resistance to catechol-o-methyltransferase (COMT) while its guanidino side-chain is resistant to monoamine oxidase (MAO). Uptake of mIBG is inhibited by some inhibitors (reserpine, tricyclic antidepressants, cocaine, labetalol, calcium-chanel blockers...). 131I-mlBG is normally taken up by liver, spleen, myocardium and salivary glands. Thyroid uptake ol liberated radioiodide will also occur unless the thyroid is blocked with stable iodide. The normal adrenal glands are usually not seen but faint uptake may be visible 48-72 h after injection in up to 16% of cases. Hepatic uptake is maximal at 24 h, declining to very low levels by 72 h (even more rapid in patients with phaeochromocytoma. Dosimetric corlsiderations limit the amount of 131l-mlBG that is administered for diagnostic studies. This, coupled with the low detection efficiency of gamma cameras for the 364 keV photon of 131l, led to the introduction of 131l-mlBG as an adrenomedullary scintigraphic agent of choice. In our department we started with mIBG scintigraphy in 1985 and we treated near 1000 patients. In this study we are talking about 180 patients from the beginning of 1996 to the end of 2001 all treated with 131l-mlBG. Like the other worldwide experience with this agent our sensitivity was 88.58% and specificity of 98.46%. Positive predictive value was 88.5% and negative predictive value was 93.46%. False negative results were 6.52% and there were no false positive results. After all we can say that mlBG has proved to be a safe, sensitive and highly specific agent for the location of phaeochromocytoma and neuroblastoma. Other radiolabelled aralkylamines have been examined as potential adrenal medullary scintigraphic agents. None has demonstrated superiority over mlBG in animal or limited human studies. 131l-mlBG should always be considered the radiopharmaceutical of choice for imaging purposes if it is available. 131l-mlBG in high doses is successfully used in therapy of malignant phaeochromocytoma and especially in nuroblastoma.
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PMID:[Nuclear medicine diagnosis of pheochromocytoma with metaiodobenzylguanidine]. 1258 93

ACTH-independent macronodular adrenal hyperplasia (AIMAH) is a rare disorder and an unusual cause of Cushing s syndrome, of which familial transmission has rarely been reported. In this study, a mother and her son, the former affected with definite AIMAH and the latter with possible AIMAH, are described. Although the mother manifested overt Cushing s syndrome, her son remained with no stigmata of Cushing s syndrome except for bilateral adrenal tumor and mild hypertension, and a full suppression of plasma cortisol by lowdose dexamethasone was observed in him. Recently, aberrant expression of adrenal receptors for various ligands has been noted in AIMAH patients. In our cases, provocation tests in vivo suggested that AVP and catecholamines promoted cortisol production through V1a and/or V1b receptors and via beta-adrenergic receptor, respectively. Reverse transcriptional-PCR analysis of the operated adrenal tissues of mother revealed the abnormal expression of mRNA of receptors for V1b, V2, and LH/hCG, none of which was observed in a normal control. Inherited AIMAH is very rare, and the son might be at the earliest developmental stage of AIMAH among the cases reported so far. An intervention could be tried to prevent the development of overt Cushing s syndrome by suppression of the possible endogenous ligands or by blockade of the receptors that may be aberrantly expressed in his adrenal glands.
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PMID:Inherited adrenocorticotropin-independent macronodular adrenal hyperplasia with abnormal cortisol secretion by vasopressin and catecholamines: detection of the aberrant hormone receptors on adrenal gland. 1262 33


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