(Conn’s syndrome, Conn’s syndrome)
A primary hyperaldosteronism is increased autonomous aldosterone in the adrenal cortex, which may be caused by a hyperplasia, an adenoma or carcinoma. Symptoms include a periodic weakness, increased blood pressure and hypokalemia. The diagnosis involves the measurement of plasma Aldosteronwerten and plasma renin activity. Treatment depends on the cause. A tumor is, if possible, removed. In hyperplasia spironolactone or related substances can normalize blood pressure and treat other ailments.
(See illustration of the adrenal function.)
A primary hyperaldosteronism is increased autonomous aldosterone in the adrenal cortex, which may be caused by a hyperplasia, an adenoma or carcinoma. Symptoms include a periodic weakness, increased blood pressure and hypokalemia. The diagnosis involves the measurement of plasma Aldosteronwerten and plasma renin activity. Treatment depends on the cause. A tumor is, if possible, removed. In hyperplasia spironolactone or related substances can normalize blood pressure and treat other ailments. (See illustration of the adrenal function.) Aldosterone is the most potent mineralocorticoid produced by the adrenal glands. It causes sodium retention and potassium loss. In the kidneys, aldosterone is responsible for the sodium transfer from the lumen of the distal tubules into the tubular cells. This is done in exchange for potassium and hydrogen. The same effects it has in the salivary glands, sweat glands, the cells of the intestinal mucosa and in the exchange between the intracellular fluid (ICF) and extracellular fluid (ECF). The aldosterone secretion is mainly through the renin-angiotensin system, and to a lesser extent by regulates the adrenocorticotropic hormone (ACTH). Renin, a proteolytic enzyme is stored in the juxtaglomerular cells of the kidney. A reduction of the blood volume and flow in the afferent renal arterioles causes a renin release. Renin converts angiotensinogen to angiotensin I from the liver, which is transformed by by angiotensin converting enzyme (ACE) to angiotensin II. It also has a pressor effect. Angiotensin II causes the release of aldosterone, and to a much lesser extent, the release of cortisol and desoxycorticosterone. due to increased aldosterone secretion, increase sodium and water retention blood volume and lower the renin secretion. Primary hyperaldosteronism is caused by mostly one-sided adenomas in glomerular cells of the adrenal cortex, or more rarely by adrenal carcinoma or hyperplasia. Adenomas in children are rare, but occurs occasionally in the syndrome childhood adrenal carcinoma or hyperplasia on. When adrenal hyperplasia, which is more common in older men, both adrenals are overactive and there is no adenoma. The same clinical picture may also occur with a congenital adrenal hyperplasia on the bottom of a 11-beta-hydroxylase deficiency, and at a dominantly inherited, inhibitable by dexamethasone hyperaldosteronism. Hyperplasia could be more common than previously thought, the cause of hyperaldosteronism, hypokalemia in it but remains a rare trigger. Symptoms and complaints may occur as late symptoms hypernatremia, Hypervolaemia and hypokalemic alkalosis. This can cause episodic weakness, paresthesias, transient paralysis, and tetany. Diastolic hypertension and a hypokalemic nephropathy with polyuria and polydipsia are common. In many cases, the only manifestation is mild to moderate hypertension. The occurrence of edema is unusual. Diagnosis electrolytes Plasmaaldosteron plasma renin activity (PRA) Imaging method of the adrenal glands Bilateral catheterization of the adrenal veins (for cortisol and aldosterone) The occurrence of hypertension and hypokalemia can be an indication of a Conn’s syndrome. The initial laboratory tests consist of determining the Plasmaaldosteronspiegel and plasma renin activity. Ideally, these determinations are performed after the patient drugs that affect the renin-angiotensin system (eg. As thiazide diuretics, ACE inhibitors, angiotensin antagonists, beta-blockers) discontinued for 4-6 weeks. The plasma renin activity is usually determined in the morning while the patient is lying. Patients with a primary hyperaldosteronism typically Plasmaaldosteronwerte> 15 ng / dl (> 0.42 nmol / l) and low values ??for the plasma renin activity, with a ratio of Plasmaaldosteron- (in ng / dl) for PRA (ng / ml / h ) of> 20. Low values ??for plasma renin activity and aldosterone have a caused not by aldosterone Mineralokortikoidexzess out (eg., by strong licorice consumption, Cushing’s syndrome or a Liddle’s syndrome). High levels of both plasma renin activity and aldosterone suggest a secondary hyperaldosteronism. The main differences between primary and secondary hyperaldosteronism are in differential diagnosis of hyperaldosteronism. clarified. In children, Bartter’s syndrome from a primary aldosteronism by the lack of high blood pressure and a significant increase in value of renin PRA is distinguished. Differential diagnosis of hyperaldosteronism. Clinical findings Primary hyperaldosteronism Secondary hyperaldosteronism adenoma hyperplasia Renal or accelerated hypertension Oedematous disorders blood pressure ?? ? ???? N or ? edema Rarely Rarely Rarely Available Serum sodium N or N or ? ? ? N or N or ? serum potassium ? ? ? N or N or ? plasma renin activity * ?? ?? ?? ? ? aldosterone ? ?? ? * When adjusted for age; Elderly patients have a lower mean plasma renin activity. ???? = greatly increased; ?? = greatly increased; = Increased ?; ?? = fell sharply; ? = decreased; N = normal. Patients with clinical findings that make primary hyperaldosteronism will probably should get a CT scan or MRI to determine if an adenoma or hyperplasia are the cause. However, imaging procedures are relatively insensitive, and most patients require a bilateral catheterization of the adrenal veins with subsequent measurement of cortisol and aldosterone levels in order to clarify whether the Aldosteronexzess occurs on one side (such as tumors) or both sides (as with the hyperplasia). It is possible that in the future the PET radionuclide imaging may be more helpful therapy Surgical removal of tumors spironolactone or eplerenone at hyperplasia tumors should be removed laparoscopically. After removal of the adenoma, the serum potassium levels and the blood pressure normalized decreases in all patients; a complete normalization of blood pressure without antihypertensive therapy is carried out at 50-70% of patients. In patients with adrenal hyperplasia 70% of patients remain after bilateral adrenalectomy hypertonic, so here surgery is not recommended. The hyperaldosteronism is in these patients usually by a selective Aldosteronblocker such. B. spironolactone controlled. One starts with 50 mg p.o. 1 times a day, increasing the dose within 1 to 3 months to the maintenance dose, which is 1 times daily at 100 mg for one month. Also, amiloride (5-10 mg) or other potassium-sparing diuretic can be used. The specific acting drug Eplerenone 50 mg p.o. up to 200 mg po 1 times a day can be used two times a day, because unlike spironolactone, it does not block the androgen receptor, it is the drug of choice for long-term treatment in men. About half of patients with hyperplasia need additional treatment with an antihypertensive. Conclusion The suspected diagnosis should be made in hypertensive patients with hypokalemia, where no Cushing’s syndrome is present. Among the initial examinations include measurement of plasma Aldosteronwerten and plasma renin activity. There are performed imaging studies of the adrenal glands, but usually bilateral catheterization of the adrenal veins is required to distinguish a tumor from hyperplasia. Tumors are removed and treated patients with adrenal hyperplasia with Aldosteronblockern such as spironolactone or eplerenone.