Adrenal Disorders Flashcards
Describe the arrangement of the adrenal veins.
The right adrenal vein drains directly into theVena Cava
The left adrenal vein drains to the left renal vein and then to the IVC (Inferior vena cava filter)
Describe the passage of blood through the adrenal gland.
The blood flows through the adrenal arteries and arterioles in the cortex where it picks up all the adrenal hormones and then it drains into a single CENTRAL VEIN.
What are the three layers of the adrenal gland from the outside to the inside?
Zona Glomerulosa (aldosterone) Zona Fasciculata (cortisol) Zona Reticularis (doesn’t do much - evolutionary remnant) Adrenal Medulla (catecholamines)
What is the precursor for ACTH?
Proopiomelanocortin – POMC
what is the different mechanism if you need cortisol or aldosterone
ACTH turn on correct enzymes to make cortisol.
Aldosterone can be made by turing on enzymes using the renin-angiotensin sysem
Why does an increase in ACTH cause hyperpigementation of the skin?
POMC is broken down to ACTH, endorphins and Melanocyte Stimulating Hormone (MCH) which stimulates the pigmentation of the skin.
What is Addison’s Disease?
Primary adrenal failure
What can Addison’s Disease be caused by? State the most common cause in the UK and the most common cause worldwide.
UK - autoimmune disease - the immune system wipes out the adrenal cortex Worldwide - tuberculosis
State some clinical features of Addison’s Disease and why does this occur
Pigmentation of the skin: body tries to compensate so pituitary glands secrete lots of ACTH and hence there is large amount of MSH
Weight loss
Hypotension: because adrenals are not producing aldosterone anymore and lack of cortisol
Muscular weakness
Autoimmune vitiligo
What are the steps that need to be taken if a patient is experiencing an Addisonian Crisis?
- Rehydrate with normal saline
- Dextrose tablets to counteract the hypoglycaemia due to lack of cortisol/glucocorticoid
- Hydrocortisone or another glucocorticoid medication
What are the consequences of excess cortisol?
Impaired glucose tolerance (due to chronic elevation of blood glucose) Interscapular fat pad
Moon face
Hypertension
Striae (stretch marks)
Thin skin and easy bruising
Proximal myopathy (weakness of large muscles)
State four causes of Cushing’s Syndrome.
Oral steroid drugs
Pituitary tumour/adenoma causing overproduction of ACTH
Ectopic(wrong place) ACTH (some lung cancer cells can produce ACTH)
Adrenal adenoma or carcinoma
What is the difference between Cushing’s Syndrome and Cushing’s Disease?
Syndrome: a collection of symptom which could be any cause e.g. moon face, striae, thin skin etc
Disease: where the cause is known to be a pituitary adenoma
what are the clinical features of cushings syndrome
Thin skin proximal myopathy centripetal obesity (lemon on sticks)) diabetes, hypertension, and osteoporosis immunosuppression moon face
What is Conn’s Syndrome?
Tumour of the zona glomerulosa (produces aldosterone)
aldosterone makes you retain sodium and lose potassium
