L4 Adrenal causes of hypertension medulla Flashcards
Where is the Zona Glomerulosa? What does it secrete?
Outermost functional section of the adrenal cortex
-closely packed cells
secretion of aldosterone (mineralocorticoids)
“salt”
Where is the Zona fascicularis? What does it secrete?
Middle function layer of the adrenal cortex
-contains clear cells in cords
regulates glucose metabolism
cortisol (glucocorticoids)
“sugar”
Reticularis
Innermost functional layer of the adrenal cortex
-contains small, darky stained cells
Produces adrenal androgens e.g testosterone
“sex”
What is Phaeochromocytoma? It results from the excess production of…?
Tumour of the adrenal medulla and originate from chromaffin cells.
Excess production of catecholamines= hypertension
10% are malignant, 10% extra-adrenal (paragangliomas), 10% bilateral, 10% familial
What is Primary Hyperaldosteronism? How do these patients present?
Conn’s syndrome
excess production of aldosterone from the adrenal glands due to hyperactivity of the cortex , resulting in low renin levels.
Presentation
- hypertension (increased Na+ absorption=increased fluid absorption)
- polyuria
How do you test Primary Hyperaldosteronism?
Initial Screening Tests
- Supressed Renin
- Normal / High Aldosterone
Confirmatory Tests
-Oral or IV Na+ supression test (shows high aldosterone)
How do you treat Primary Hyperaldosteronism?
Unilateral Adenoma
-Laparoscopic Adrenalectomy
-Medical Treatment
Bilateral Hyperplasia Medical Treatment (Aldosterone Antagonists)
- Spironolactone
- Eplerinone
Clinical diagnosis of Neurofibromatosis Type 1
Axillary Freckling
What can elevate catecholamine levels?
- Obstructive Sleep Apnoea
- Amphetamine like drugs
- L-DOPA
- Labetalol
Biological effects of Noradrenalin
Alpha 1 and 2 Vasoconstriction -Increased BP -Pallor Glycogenolysis
Biological effects of Adrenalin
alpha 1, beta 1 and 2
- Vasoconstriction
- Vasodilatation in Muscle (B2)
- Increased heart rate
- Sweating
Presentation of Phaeochomocytoma
- Headache, Sweating
- Pallor, Palpitations
- Anxiety
-Hypertension
Permanent
Intermittent
-Family history
Pharmacological and Surgical Treatment of Phaeochomocytoma
Alpha Blockers
- block alpha adrenoreceptors
- Phenoxybenzamine
- Doxazocin
Beta Blockers
-Propranolol
Laparoscopic adrenalectomy
Surgery (Laparocscopic adrenalectomy)
Genetic conditions associated with pheochromocytoma/risk factors
Neurofibromatosis T1 (NF1)
Multiple endocrine neoplasia type 2
Von Hippel-Lindau syndrome
How would you diagnose Phaeochromocytoma
24 hour urine
