A disorder that results from the excessive production of the hormone aldosterone from one or both adrenal glands. Aldosteronism caused by an adrenal tumour is known as Conn’s syndrome. Aldosteronism may also be caused by disorders, such as heart failure or liver damage, that reduce the flow of blood through the kidneys. Reduced blood flow through the kidneys leads to overproduction of renin and angiotensin, which, in turn, leads to excessive aldosterone production.
Symptoms are directly related to the actions of aldosterone. Too much sodium is retained in the body, leading to a rise in blood pressure, and excess potassium is lost in the urine. Low potassium causes tiredness and muscle weakness and impairs kidney function, leading to thirst and overproduction of urine.
Treatment in all cases includes restriction of dietary salt and use of the diuretic drug spironolactone.
If the cause of aldosteronism is an adrenal tumour, this may be surgically removed.
(hyperaldosteronism) n. overproduction of aldosterone, one of the hormones secreted by the adrenal cortex, usually due to a benign tumour (adenoma) in the cortex or hyperplasia of that tissue. It leads to abnormalities in the amounts of sodium, potassium, and water in the body. It is a rare cause of raised blood pressure (hypertension). See also Conn’s syndrome.
Cancerous or noncancerous tumours in the adrenal glands, usually causing excess secretion of hormones. Adrenal tumours are rare. Tumours of the adrenal cortex may secrete aldosterone, causing primary aldosteronism, or hydrocortisone, causing Cushing’s syndrome. Tumours of the medulla may cause excess secretion of adrenaline and noradrenaline. Two types of tumour affect the medulla: phaeochromocytoma and neuroblastoma, which affects children. These tumours cause intermittent hypertension and sweating attacks. Surgical removal of a tumour usually cures these conditions.... adrenal tumours
(RTA) metabolic acidosis due to failure of the kidney to excrete acid into the urine. Three types of RTA are recognized. Type 1 (distal RTA) results from a reduction in net acid secretion in the distal convoluted tubule (see nephron) and an inability to acidify the urine. Hypokalaemia is often present and may be severe. The condition can be either genetically determined or, more commonly, the result of systemic disease (e.g. autoimmune disorders) or drugs (e.g. amphotericin). Type II (proximal RTA) is due to a lowered threshold for bicarbonate reabsorption; eventually a steady state is established with a low serum bicarbonate but capacity to acidify the urine. Hypokalaemia is present due to *aldosteronism caused by the increased delivery of sodium to the distal tubule. Proximal RTA usually occurs as part of more widespread proximal tubule dysfunction with the *Fanconi syndrome. Type IV RTA results from impaired excretion of both acid and potassium and results in acidosis with hyperkalaemia. It is most commonly seen with aldosterone deficiency. This may be isolated, especially in diabetics, or it may be induced by drugs (angiotensin II antagonists or ACE inhibitors).... renal tubular acidosis
n. a synthetic corticosteroid that inhibits the activity of the hormone *aldosterone and is used as a potassium-sparing *diuretic to treat fluid retention (oedema) in cirrhosis, *ascites, and severe heart failure. It is also used in treating aldosteronism. Side-effects may include headache, stomach upsets, breast enlargement and impotence (in men), and menstrual disturbances (in women).... spironolactone
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