T1 L4: Adrenal hypertension Flashcards
What are the 3 causes of hypertension?
- Essential
- Renal
- Endocrine
What is essential hypertension?
Abnormal BP that isn’t caused by a medical condition
What are the 2 renal causes of hypertension?
- Primary renal disease
2. Renal artery stenosis
What is the cause of primary Hyperaldosteronism?
Adenoma, hyperplasia, or a genetic disorder affecting the zona Glomerulosa
What is a Phaeochromocytoma (A Phaeo)?
A tumour of the adrenal medulla that grown in Chromaffin cells
Describe the pathway of aldosterone secretion
Angiotensinogen is released by the liver and renin is released by the kidneys. Renin converts angiotensinogen into angiotensin I and then ACE converts angiotensin I into angiotensin II. Aldosterone is then produced
What is Primary Hyperaldosteronism?
When the adrenal glands produce too much aldosterone
What is Conn’s disease?
Primary Hyperaldosteronism
When should someone with hypertension be screened for Primary hyperaldosteronism (Conn’s disease)?
- Hypokalaemia
- Resistant hypertension
- Younger people
What does Liquorice have to do with aldosterone levels?
It causes aldosterone levels to decrease by reducing Renin
What are the initial screening tests for primary hyperaldosteronism?
Supressed renin and normal/high aldosterone tests
What is the confirmatory test for primary aldosteronism?
Oral or IV Na+ suppression test
Urinary aldosterone is then measured
Normal= low aldosterone
What are some tests for specific aetiology for primary hyperaldosteronism?
- Adrenal CT
- Adrenal venous sampling
- Metomidate PET CT
Under what conditions does cortisol turn norepinephrine into epinephrine?
Where there are high concentrations of cortisol Eg. in the adrenal medulla
What are the biological effects of Noradrenaline?
Vasoconstriction
Glycogenolysis
Which receptors does noradrenaline attach to?
Alpha 1 and alpha 2
What are the biological effects of Adrenalin?
Vasoconstriction
Vasodilatation in muscles
Increased heart rate
Sweating
Which receptors does adrenaline attach to?
Alpha 1, beta 1, and beta 2
What are the clinical presentations of Paeochronocytomas?
Spells of headache, sweating, pallor, palpitations, anxiety
Hypertension
What are some genetic conditions associated with pheochromocytomas?
Neurofibromatosis Type 1 (NF1)
- Tumours that grow along nerves
Multiple Endocrine Neoplasia Type 2 (MEN 2)
- hereditary condition associated with 3 primary types of tumours: medullary thyroid cancer, parathyroid tumours, and pheochromocytoma
Von Hippel - Lindau syndrome
- Tumours arising in multiple organs
What is the diagnostic process for Paeochromocytomas?
24 hour urine to meaure normetanephrines and metanephrines
Plasma taken to measure noradrenaline and adrenaline
Which conditions other than paeochromocytomas can raise catecholamine levels?
- Obstructive sleep apnoea
- amphetamine like drugs
- L-dopa
- Labetalol (used for hypertension)
Where in the body does urinary dopamine come from?
From the kidney and nervous system
What is a MIBG scan?
A scanner that finds or confirms the presence of pheochromocytoma and neuroblastoma
A substance is injected and abnormal growth is highlighted
What is the management for paeochromocytomas?
Surgery to remove the tumour
Alpha and beta blockers to reduce hypertension
What is the post adrenalectomy care?
- Genetic testing because 30% of tumours are genetic
- Annual metanephrines
- Additional treatment if malignant
