Primary Hyperaldosteronism

Home
Keys to Success in Medicine
Cardiovascular System
Respiratory System
Locomotor System
Endocrine and Metabolic System
Kidneys and Urinary System
Gastrointestinal Tract
Central Nervous System
Haematological System
Integumental System
Reproductive and Genital System
Analysing Medical Investigations
Recommended Reading
Forum
Links

amazon astore

ydr

aces for paces

Clinical Skills Blogspot

 

Google
Web ydr.org.uk
acesforpaces.com medicalrevision.org

 

 

Primary Hyperaldosteronism             

Title               

Ñ    Primary Hyperaldosteronism        

Definition

Ñ    Excess production of aldosterone

Ñ    Independent of the renin-angiotensin axis

Pathogenesis

Ñ    Adrenal adenoma:

Conn’s syndrome

Ñ    Bilateral adrenal hyperplasia

Ñ    Adrenal carcinoma:

Rare

Ñ    Glucocorticoid-remediable aldosteronism (GRA):

Condition where aldosterone production is under the control of ACTH

Pathophysiology

Ñ    Increased physiological effects of aldosterone

Clinical Features

History

Ñ    Adenoma:

More common in young females

Ñ    Bilateral adrenal hyperplasia:

Rare under the age of 40 years

More common in males

KUS

Ñ    Nocturia

CNS

Ñ    Muscle weakness

Ñ    Tetany

Examination

CVS

Ñ    Hypertension

Investigations

The objectives of investigation are:

Ñ    Establish diagnosis

Ñ    Differentiate cause

Establish Diagnosis

Fluids

Blood

Biochemistry

Ñ    Hypokalaemic alkalosis

Ñ    Increased aldosterone: plasma renin activity ratio

Urine

Ñ    Potassium loss:

> 30 mmol/day in the presence of hypokalaemia

Differentiate cause

Adenoma or hyperplasia:

Fluids

Blood

Biochemistry

Ñ    Selective venous catheterisation for aldosterone levels

Ñ    18-OH cortisol:

Increased in adenoma

Ñ    0800 supine, 1200 erect blood levels of aldosterone, cortisol:

·          In normal people aldosterone levels rise when they are erect and the 1200 level is approximately twice 0800 level

·          This response is seen in adrenal hyperplasia

·          In adenoma and GRA aldosterone is under the control of ACTH and hence levels fall:

Rare exception is angiotensin II sensitive adenoma

Ñ    Overnight dexamethasone suppression test:

Suppresses aldosterone production in GRA

Imaging

CT or MRI

Ñ    May miss small tumours

Nuclear Medicine

Adrenal scintigraphy

Ñ    Unilateral or bilateral uptake

Management

Control

Drugs

Ñ    Spironolactone

Ñ    Amiloride

Ñ    Dexamethasone:

For GRA

Surgery

Ñ    Adenoma

 

 

[ Back ] [ Up ] [ Next ]

 

 

[Up]