Hyperaldosteronism is a
medical condition wherein too much
aldosterone
Aldosterone is the main mineralocorticoid steroid hormone produced by the zona glomerulosa of the adrenal cortex in the adrenal gland. It is essential for sodium conservation in the kidney, salivary glands, sweat glands, and colon. It plays a c ...
is produced by the
adrenal glands
The adrenal glands (also known as suprarenal glands) are endocrine glands that produce a variety of hormones including adrenaline and the steroids aldosterone and cortisol. They are found above the kidneys. Each gland has an outer cortex which ...
, which can lead to lowered levels of
potassium
Potassium is the chemical element with the symbol K (from Neo-Latin ''kalium'') and atomic number19. Potassium is a silvery-white metal that is soft enough to be cut with a knife with little force. Potassium metal reacts rapidly with atmosphe ...
in the
blood
Blood is a body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells, and transports metabolic waste products away from those same cells. Blood in the c ...
(
hypokalemia) and increased hydrogen ion excretion (
alkalosis
Alkalosis is the result of a process reducing hydrogen ion concentration of arterial blood plasma (alkalemia). In contrast to acidemia (serum pH 7.35 or lower), alkalemia occurs when the serum pH is higher than normal (7.45 or higher). Alkalosis i ...
).
This cause of mineralocorticoid excess is primary hyperaldosteronism reflecting excess production of aldosterone by adrenal
zona glomerulosa
The ''zona glomerulosa'' (sometimes, glomerular zone) of the adrenal gland is the most superficial layer of the adrenal cortex, lying directly beneath the renal capsule. Its cells are ovoid and arranged in clusters or arches (''glomus'' is Latin ...
. Bilateral micronodular hyperplasia is more common than unilateral adrenal adenoma.
Signs and symptoms
It can be
asymptomatic
In medicine, any disease is classified asymptomatic if a patient tests as carrier for a disease or infection but experiences no symptoms. Whenever a medical condition fails to show noticeable symptoms after a diagnosis it might be considered asy ...
, but these symptoms may be present:
*
Fatigue
Fatigue describes a state of tiredness that does not resolve with rest or sleep. In general usage, fatigue is synonymous with extreme tiredness or exhaustion that normally follows prolonged physical or mental activity. When it does not resolve ...
*
Headache
Headache is the symptom of pain in the face, head, or neck. It can occur as a migraine, tension-type headache, or cluster headache. There is an increased risk of depression in those with severe headaches.
Headaches can occur as a result ...
*
High blood pressure
Hypertension (HTN or HT), also known as high blood pressure (HBP), is a long-term medical condition in which the blood pressure in the arteries is persistently elevated. High blood pressure usually does not cause symptoms. Long-term high bl ...
*
Hypokalemia
*
Hypernatraemia
Hypernatremia, also spelled hypernatraemia, is a high concentration of sodium in the blood. Early symptoms may include a strong feeling of thirst, weakness, nausea, and loss of appetite. Severe symptoms include confusion, muscle twitching, and b ...
*
Hypomagnesemia
* Intermittent or temporary
paralysis
Paralysis (also known as plegia) is a loss of motor function in one or more muscles. Paralysis can also be accompanied by a loss of feeling (sensory loss) in the affected area if there is sensory damage. In the United States, roughly 1 in 50 ...
*
Muscle spasms
*
Muscle weakness
Muscle weakness is a lack of muscle strength. Its causes are many and can be divided into conditions that have either true or perceived muscle weakness. True muscle weakness is a primary symptom of a variety of skeletal muscle diseases, includi ...
*
Numbness
*
Polyuria
Polyuria () is excessive or an abnormally large production or passage of urine (greater than 2.5 L or 3 L over 24 hours in adults). Increased production and passage of urine may also be termed diuresis. Polyuria often appears in conjunction with ...
*
Polydipsia
Polydipsia is excessive thirst or excess drinking.Porth, C. M. (1990). ''Pathophysiology: Concepts of altered health states''. Philadelphia: J.B. Lippincott Company. The word derives from the Greek () "very thirsty", which is derived from (, "mu ...
* Tingling
*
Metabolic alkalosis
Metabolic alkalosis is a metabolic condition in which the pH of tissue is elevated beyond the normal range (7.35–7.45). This is the result of decreased hydrogen ion concentration, leading to increased bicarbonate, or alternatively a direct resu ...
* Nocturia
* Blurry Vision
* Dizziness/Vertigo
Cause
The causes of primary hyperaldosteronism are
adrenal hyperplasia and
adrenal adenoma
Adrenocortical adenoma is commonly described as a benign neoplasm emerging from the cells that comprise the adrenal cortex. Like most adenomas, the adrenocortical adenoma is considered a benign tumor since the majority of them are non-functioning ...
(
Conn's syndrome).
These cause
hyperplasia
Hyperplasia (from ancient Greek ὑπέρ ''huper'' 'over' + πλάσις ''plasis'' 'formation'), or hypergenesis, is an enlargement of an organ or tissue caused by an increase in the amount of organic tissue that results from cell proliferati ...
of aldosterone-producing cells of the
adrenal cortex
The adrenal cortex is the outer region and also the largest part of an adrenal gland. It is divided into three separate zones: zona glomerulosa, zona fasciculata and zona reticularis. Each zone is responsible for producing specific hormones. It is ...
resulting in primary hyperaldosteronism.
The causes of secondary hyperaldosteronism are accessory renal veins,
fibromuscular dysplasia, reninoma, renal tubular acidosis, nutcracker syndrome, ectopic tumors, massive
ascites,
left ventricular failure, and
cor pulmonale.
These act either by decreasing circulating fluid volume or by decreasing cardiac output, with resulting increase in
renin
Renin (etymology and pronunciation), also known as an angiotensinogenase, is an aspartic protease protein and enzyme secreted by the kidneys that participates in the body's renin–angiotensin–aldosterone system (RAAS)—also known as the r ...
release leading to secondary hyperaldosteronism. Secondary hyperaldosteronism can also be caused by
proximal renal tubular acidosis
Proximal renal tubular acidosis (pRTA) or type 2 renal tubular acidosis (RTA) is a type of RTA caused by a failure of the proximal tubular cells to reabsorb filtered bicarbonate from the urine, leading to urinary bicarbonate wasting and subsequen ...
Secondary hyperaldosteronism can also be a symptom of genetic conditions Bartter's Syndrome and Gitelman's Syndrome.
Diagnosis
When taking a
blood test
A blood test is a laboratory analysis performed on a blood sample that is usually extracted from a vein in the arm using a hypodermic needle, or via fingerprick. Multiple tests for specific blood components, such as a glucose test or a cholester ...
, the
aldosterone-to-renin ratio is abnormally increased in
primary hyperaldosteronism, and decreased or normal but with high
renin
Renin (etymology and pronunciation), also known as an angiotensinogenase, is an aspartic protease protein and enzyme secreted by the kidneys that participates in the body's renin–angiotensin–aldosterone system (RAAS)—also known as the r ...
in secondary hyperaldosteronism.
Types
In
endocrinology
Endocrinology (from '' endocrine'' + '' -ology'') is a branch of biology and medicine dealing with the endocrine system, its diseases, and its specific secretions known as hormones. It is also concerned with the integration of developmental event ...
, the terms 'primary' and 'secondary' are used to describe the abnormality (e.g., elevated aldosterone) in relation to the defect, ''i.e.'', the tumor's location. It also refers to causes that are genetic (primary) or due to another condition or influence (secondary).
Primary
Primary aldosteronism (hyporeninemic hyperaldosteronism) was previously thought to be most commonly caused by an
adrenal adenoma
Adrenocortical adenoma is commonly described as a benign neoplasm emerging from the cells that comprise the adrenal cortex. Like most adenomas, the adrenocortical adenoma is considered a benign tumor since the majority of them are non-functioning ...
, termed
Conn's syndrome. However, recent studies have shown that bilateral idiopathic adrenal hyperplasia is the cause in up to 70% of cases. Differentiating between the two is important, as this determines treatment. Also, see
congenital adrenal hyperplasia
Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive disorders characterized by impaired cortisol synthesis. It results from the deficiency of one of the five enzymes required for the synthesis of cortisol in the adrenal cortex. ...
.
Adrenal carcinoma is an extremely rare cause of primary hyperaldosteronism.
Two
familial forms have been identified:
type I Type 1 or Type I or ''variant'', may refer to:
Health
*Diabetes mellitus type 1 (also known as "Type 1 Diabetes"), insulin-dependent diabetes
* Type I female genital mutilation
* Type 1 personality
*Type I hypersensitivity (or immediate hypersensit ...
(
dexamethasone
Dexamethasone is a glucocorticoid medication used to treat rheumatic problems, a number of skin diseases, severe allergies, asthma, chronic obstructive lung disease, croup, brain swelling, eye pain following eye surgery, superior vena cav ...
suppressible), and type II, which has been linked to the 7p22 gene.
Features
*
Hypertension
Hypertension (HTN or HT), also known as high blood pressure (HBP), is a long-term medical condition in which the blood pressure in the arteries is persistently elevated. High blood pressure usually does not cause symptoms. Long-term high bl ...
*
Hypokalemia (e.g., may cause muscle weakness)
*
Alkalosis
Alkalosis is the result of a process reducing hydrogen ion concentration of arterial blood plasma (alkalemia). In contrast to acidemia (serum pH 7.35 or lower), alkalemia occurs when the serum pH is higher than normal (7.45 or higher). Alkalosis i ...
Investigations
* High serum
aldosterone
Aldosterone is the main mineralocorticoid steroid hormone produced by the zona glomerulosa of the adrenal cortex in the adrenal gland. It is essential for sodium conservation in the kidney, salivary glands, sweat glands, and colon. It plays a c ...
* Low serum
renin
Renin (etymology and pronunciation), also known as an angiotensinogenase, is an aspartic protease protein and enzyme secreted by the kidneys that participates in the body's renin–angiotensin–aldosterone system (RAAS)—also known as the r ...
* High-resolution CT abdomen
Management
* Adrenal adenoma: surgery
* Bilateral adrenocortical hyperplasia: aldosterone antagonist, e.g.,
spironolactone
Spironolactone, sold under the brand name Aldactone among others, is a medication that is primarily used to treat fluid build-up due to heart failure, liver scarring, or kidney disease. It is also used in the treatment of high blood pressure ...
Secondary
* Secondary hyperaldosteronism (also hyperreninism, or hyperreninemic hyperaldosteronism) is due to overactivity of the
renin–angiotensin–aldosterone system (RAAS).
Secondary refers to an abnormality that indirectly results in pathology through a predictable physiologic pathway, i.e., a
renin
Renin (etymology and pronunciation), also known as an angiotensinogenase, is an aspartic protease protein and enzyme secreted by the kidneys that participates in the body's renin–angiotensin–aldosterone system (RAAS)—also known as the r ...
-producing tumor leads to increased aldosterone, as the body's aldosterone production is normally regulated by renin levels. One cause is a
juxtaglomerular cell tumor
Juxtaglomerular cell tumor (JCT, JGCT, also reninoma) is an extremely rare kidney tumour of the juxtaglomerular cells, with less than 100 cases reported in literature. This tumor typically secretes renin, hence the former name of reninoma. It ofte ...
. Another is
renal artery stenosis, in which the reduced blood supply across the
juxtaglomerular apparatus
The juxtaglomerular apparatus (also known as the juxtaglomerular complex) is a structure in the kidney that regulates the function of each nephron, the functional units of the kidney. The juxtaglomerular apparatus is named because it is next to ...
stimulates the production of renin. Likewise,
fibromuscular dysplasia may cause stenosis of the renal artery, and therefore secondary hyperaldosteronism. Other causes can come from the tubules: low reabsorption of sodium (as seen in Bartter and Gitelman syndromes) will lead to hypovolemia/hypotension, which will activate the
renin–angiotensin system
The renin–angiotensin system (RAS), or renin–angiotensin–aldosterone system (RAAS), is a hormone system that regulates blood pressure, fluid and electrolyte balance, and systemic vascular resistance.
When renal blood flow is reduced, juxt ...
(RAAS).
Secondary hyperaldosteronism can also be caused by excessive ingestion of
licorice
Liquorice (British English) or licorice (American English) ( ; also ) is the common name of ''Glycyrrhiza glabra'', a flowering plant of the bean family Fabaceae, from the root of which a sweet, aromatic flavouring can be extracted.
The liq ...
or other members of the ''
Glycyrrhiza'' genus of plants that contain the
triterpenoid
Triterpenes are a class of chemical compounds composed of three terpene units with the molecular formula C30H48; they may also be thought of as consisting of six isoprene units. Animals, plants and fungi all produce triterpenes, including squale ...
saponin
Saponins (Latin "sapon", soap + "-in", one of), also selectively referred to as triterpene glycosides, are bitter-tasting usually toxic plant-derived organic chemicals that have a foamy quality when agitated in water. They are widely distributed ...
glycoside
In chemistry, a glycoside is a molecule in which a sugar is bound to another functional group via a glycosidic bond. Glycosides play numerous important roles in living organisms. Many plants store chemicals in the form of inactive glycosides. ...
known as
glycyrrhizin
Glycyrrhizin (or glycyrrhizic acid or glycyrrhizinic acid) is the chief sweet-tasting constituent of ''Glycyrrhiza glabra'' ( liquorice) root. Structurally, it is a saponin used as an emulsifier and gel-forming agent in foodstuffs and cosmet ...
. Licorice and closely related plants are perennial shrubs, the roots of which are used in medicine as well as making candies and in cooking other desserts because of the sweet taste. Through inhibition of
11-beta-hydroxysteroid dehydrogenase type 2 (11-beta-HSD2), glycyrrhizin allows
cortisol
Cortisol is a steroid hormone, in the glucocorticoid class of hormones. When used as a medication, it is known as hydrocortisone.
It is produced in many animals, mainly by the ''zona fasciculata'' of the adrenal cortex in the adrenal gland ...
to activate
mineralocorticoid receptors in the kidney. This severely potentiates mineralocorticoid receptor-mediated renal sodium reabsorbtion, due to much higher circulating concentrations of cortisol compared to aldosterone. This, in turn, expands the
extracellular volume
In cell biology, extracellular fluid (ECF) denotes all body fluid outside the cells of any multicellular organism. Total body water in healthy adults is about 60% (range 45 to 75%) of total body weight; women and the obese typically have a lower ...
, increases
total peripheral resistance
Vascular resistance is the resistance that must be overcome to push blood through the circulatory system and create flow. The resistance offered by the systemic circulation is known as the systemic vascular resistance (SVR) or may sometimes be ca ...
and increases
arterial blood pressure. The condition is termed
pseudohyperaldosteronism
Pseudohyperaldosteronism (also pseudoaldosteronism) is a medical condition which mimics the effects of elevated aldosterone (hyperaldosteronism) by presenting with high blood pressure (hypertension), low blood potassium levels (hypokalemia), metabo ...
.
Secondary hyperaldosterone can also be caused by a genetic mutation in the kidneys which causes sodium and potassium wasting. These conditions can be referred to syndromes such as Bartter Syndrome and Gitelman Syndrome.
Treatment
Treatment includes removing the causative agent (such as licorice), a high-potassium, low-sodium diet (for primary) and high-sodium diet (for secondary),
spironolactone
Spironolactone, sold under the brand name Aldactone among others, is a medication that is primarily used to treat fluid build-up due to heart failure, liver scarring, or kidney disease. It is also used in the treatment of high blood pressure ...
and
eplerenone
Eplerenone, sold under the brand name Inspra, is an aldosterone antagonist type of potassium-sparing diuretic that is used to treat chronic heart failure and high blood pressure, particularly for patients with resistant hypertension due to elevat ...
,
potassium-sparing diuretic
Potassium-sparing diuretics refers to drugs that cause diuresis without causing potassium loss in the urine. They are typically used as an adjunct in management of hypertension, cirrhosis, and congestive heart failure. The steroidal aldosterone ...
s that act as
aldosterone antagonist
An antimineralocorticoid, also known as a mineralocorticoid receptor antagonist (MRA or MCRA) or aldosterone antagonist, is a diuretic drug which antagonizes the action of aldosterone at mineralocorticoid receptors. This group of drugs is often u ...
s, and surgery, depending on the cause.
Secondary hyperaldosteronism may also be treated with cox2 inhibitors which cause water retention, sodium retention and potassium retention as well as raising blood pressure. Bartter and Gitleman syndrome tend to cause low blood pressure in significant populations and treatment with blood pressure medications tend to lower the blood pressure even more.
Other animals
Cats can be affected by hyperaldosteronism. The most common signs in cats are muscle weakness and loss of eyesight, although only one of these signs may be present.
Muscle weakness is due to low potassium concentrations in the blood, and signs of muscle weakness, such as being unable to jump, may be intermittent.
High blood pressure causes either detachment of the retina, or blood inside the eye, which leads to loss of vision.
Hyperaldosteronism caused by a tumor is treated by surgical removal of the affected adrenal gland.
See also
*
Hypoaldosteronism
Hypoaldosteronism is an endocrinological disorder characterized by decreased levels of the hormone aldosterone. Similarly, isolated hypoaldosteronism is the condition of having lowered aldosterone without corresponding changes in cortisol. (The ...
*
Glucocorticoid remediable aldosteronism
Glucocorticoid remediable aldosteronism also describable as ''aldosterone synthase hyperactivity'', is an autosomal dominant disorder in which the increase in aldosterone secretion produced by ACTH is no longer transient.
It is a cause of primary ...
References
External links
Primary Hyperaldosteronism Nursing Management{Medical resources
, DiseasesDB = 6187
, ICD10 = {{ICD10, E, 26, , e, 20
, ICD9 = {{ICD9, 255.1
, ICDO =
, OMIM = 103900
, OMIM_mult = {{OMIM, 605635, , none
, MedlinePlus = 000330
, eMedicineSubj = radio
, eMedicineTopic = 354
, MeshID = D006929
Adrenal gland disorders