Hyperaldosteronism
Hyperaldosteronism Main page |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Mehrian Jafarizade, M.D [2]
This page contains general information about Hyperaldosteronism. For more information on specific types, please visit the pages on Primary hyperaldosteronism, and Secondary hyperaldosteronism.
Synonyms and keywords: Aldosteronism
Overview
Classification
Aldosteronism and mineralocorticoid excess may be classified into two types, primary hyperaldosteronism (conn's syndrome) and secondary hyperaldosteronism. The different types of aldosteronism described in the below table:
Primary hyperaldosteronism | Category | Diseases |
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Adrenal causes | Aldosterone-secreting adrenal adenoma | |
Idiopathic hyperaldosteronism
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Extra-adrenal causes | Ectopic secretion of aldosterone | |
Familial hyperaldosteronism | Familial hyperaldosteronism type I
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Familial hyperaldosteronism II
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Familial hyperaldosteronism type III
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Other | Pure aldosterone-producing adrenocortical carcinomas | |
Unilateral adrenal hyperplasia | ||
Secondary hyperaldosteronism | Genetic mutation | Bartter and Gitelman syndromes (hyperplasia of the juxtaglomerular apparatus, the source of renin in the kidney) |
Endocrine causes | Cushing syndrome
of cortisol which saturates 11-HSD2 activity,
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Ectopic ACTH production (Secondary to carcinomas such as lung cancer) | ||
Renovascular | Kidney transplant | |
Renin-secreting juxtaglomerular cell tumors | ||
Scleroderma renal crisis | ||
Malignant hypertension | ||
Tumors | Reninoma | |
Intravascular hypovolemia |
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Pseudohyperaldosteronism causes (low renin):
Pseudohyperaldosteronism causes | Disease | Etiology | Clinical features | Labratory | ||||
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Elevated mineralocorticoid | Renin | Aldosterone | Other | Treatment | ||||
Endogenous causes | 17 alpha-hydroxylase deficiency | Mutations in the CYP17A1 gene |
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Deoxycorticosterone (DOC) | ↓ | ↓ | Cortisol ↓ | Corticosteroids |
11β-hydroxylase deficiency | Mutations in the CYP11B1 gene |
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Cortisol ↓ | |||||
Apparent mineralocorticoid excess syndrome (AME) | Genetic or acquired defect of 11-HSD
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Cortisol has mineralocorticoid effects | ↓ | ↓ | Urinary free cortisone ↓↓ | Dexamethasone and/or mineralocorticoid blockers | |
Liddle’s syndrome (Pseudohyperaldosteronism type 1) | Mutation of the epithelial sodium channels (ENaC) gene in the distal renal tubules |
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No extra mineralocorticoid presents, and mutations in Na channels mimic aldosterone mechanism | ↓ | ↓ | Cortisol ↓ | amiloride or triamterene can reverse the clinical picture reactivating the renin aldosterone | |
Cushing’s syndrome | The main pathogenetic mechanism is linked to the excess
of cortisol which saturates 11-HSD2 activity, allowing cortisol to bind MR. A similar picture is also related to over secretion of cortisol by adrenocortical carcinomas. In some cases the disease is associated with secondary hyperaldosteronism due to a direct activation of the renin angiotensin system by glucocorticoids. |
Rapid weight gain, particularly of the trunk and face with limbs sparing (central obesity)
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Cortisol has mineralocorticoid effects | ↓ |
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Urinary free cortisol markedly ↑↑ |
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Insensitivity to glucocorticoids (Chrousos syndrome) | Mutations in glucocorticoid receptor (GR) gene |
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Deoxycorticosterone (DOC) | ↓ | ↓ | Cortisol | Dexamethasone | |
Aldosterone-secreting adrenocortical carcinoma | Cortisol has mineralocorticoid effects | ↓ |
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Urinary free cortisol markedly ↑↑ | ||||
Geller’s syndrome | mutation of MR that alters its specificity and allows progesterone to bind MR | severe hypertension particularly during pregnancy | ↓ | ↓ | ||||
Gordon’s syndrome (Pseudohypoaldosteronism type 2) | Mutations of at least four genes have been identified, including WNK1 and WNK4 |
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No excess mineralocorticoid; an increased activity of the thiazide-sensitive Na–Cl co-transporter in the distal tubule | ↓ | Normal | Hyperkalemia | thiazide diuretics and/or dietary sodium restriction | |
Exogenous causes | Corticosteroids with mineralocorticoid activity | Fludrocortisone or fluoroprednisolone can mimic the action of aldosterone, |
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Medications such as Fludrocortisone | ↓ | ↓ | - | Change the treatment |
Licorice ingestion | glycyrrhetinic acid that binds MR and blocks 11-HSD2 at the level of classical target tissues of aldosterone | ↓ | ↓ | Urinary free cortisol Moderate ↑ | ||||
grapefruit | High assumption of naringenin, a component of grapefruit, can also block 11-HSD | |||||||
Contraceptives | Estrogens can retain sodium and water by different mechanisms, causing increased blood pressure values and suppressing the renin aldosterone system. However, contraceptives usually cause hypertension through a secondary hyperaldosteronism due to the stimulation of the synthesis of angiotensinogen | |||||||
Particular causes of hypertension | Sclerosis of juxtaglomerular apparatus (diabetic microangiopathy and/or of the elderly) | |||||||
FANS | ||||||||
B-Adrenergic agonists | ||||||||
Aging | ||||||||
Low-renin essential hypertension | ||||||||
Autonomic dysfunction | ||||||||
Partial/total nephrectomy or removal of renal tissue |
Differentiating Diagnosis
Hyperaldosteronism should be differentiated from other diseases causing hypertension and hypokalemia for example:
- Renal artery stenosis
- Cushing's syndrome
- Congenital adrenal hyperplasia (CAH)
- Liddle's syndrome
- Diuretic use
- Licorice ingestion
- Renin-secreting tumors
Hypertension and Hypokalemia | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Plasma renin activity | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Normal or High (Plasma Renin/Aldosterone ratio <10 | Suppressed (Plasma Renin/Aldosterone ratio >20 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
*Renin-secreting tumors *Diuretic use *Renovascular hypertension *Coarctation of aorta *Malignant phase hypertension | Urinary aldosterone | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Elevated | Normal | Low | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Conn's syndrome (Primary aldosteronism) | Profound K+ depletion | • 17 alpha hydroxylase deficiency • 11 beta hydroxylase deficiency • Liddle's syndrome • Licorice ingestion • Deoxycortisone producing tumor | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Add Mineralocrticoid antagonist for 8 weeks | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
BP response | No BP response | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
• Deoxycorticosterone excess( Tumor, 17 alpha hydroxylase and 11 beta hydroxylase deficiency) • Licorice ingestion •Glucocorticoid resistance | Liddle's syndrome) | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||