Adrenal Disorders Flashcards
What is Cushings?
Hypercortisolism
What is Conn’s?
Hyperaldosteronism
What is Addison’s?
Hypoadrenalism
What happens in Conn’s?
Excessive aldosterone causes Na retention, increased plasma and ECF volume, hypokalaemia and HTN
All supresses Renin
Alkalosis
What causes Conn’s?
Adrenal adenoma (70%) Bilateral adrenal hyperplasia
What causes secondary hyperaldosteronism?
Renal artery stenosis/obstruction
Heart Failure
Causes high renin which stimulates aldosterone production
What are symptoms and signs of Excessive aldosterone?
HTN- LVH/MI renal failure
Hypernatraemia signs
Hypokalaemia- DI, thirst, polyuria, polydipsia, neuromuscular weakness, tetany and paraesthesia
How do you investigate Hyperaldosteronism?
Exclude other causes of hypokalaemia (diuretics/laxatives)
Measure aldosterone:renin ratio
Imaging
What is the mechanism of Cushings?
Chronic excessive cortisol and loss of circadian rhythms
Who gets cushings?
Male
Prepubescent
What is the difference between Cushings disease and syndrome?
Syndrome- Adrenal adenoma/ steroids/ paraneoplastic- 30%
Disease- Pituitary tumour (ACTH dependent)- 70%
What are clinical features of cushings?
HTn Central obesity Hirsutism DM Osteoporosis Straie Red Moon face Bufalo hump Depression and psychosis Impotence Hypokalaemia Acne Recurrent achilles tendonitis
How is Cushing investigated?
Repeated tests and clinical judgement needed
DEXAMETHASONE supression test- then measure ACTH and cortisol in the morning to see if morning spike reduced. First low dose then high
If pit cause= ACTH low, cort low
If adrenal cause+ ACTH low cort high
24 hour free cortisol (>2 measurements) and measure ACTH
Imaging
Refer to endocrinology
When do you get high cortisol physiologically?
Pregnancy Depression Morbid obesity DM Alcohol dependence Stress Malnutrition Chronic excercise
How is Cushings managed?
Surgery/radio
Cabergoline to act on pit or Ketoconadazole or mifepristone to act on adrenals
What is the mechanism in Addisons?
Adrenal insufficiency means reduced aldosterone and cortisol
What causes primary adrenal insufficiency?
Addisons- autoimmune destruction of cortex
TB
Lymphoma
How is primary adrenal insufficiency diagnosed?
9am cortisol low
Increased ACTH
Low Aldosterone
Syntrophin test
What causes secondary adrenal insufficiency?
Steroid excess supresses adrenal axis
Pituitary tumours
Head trauma
What is most common cause of adrenal insufficiency
CAH
What are symptoms of adrenal insufficiency>
Anorexia Weakness and fatigue Weight loss Hyperpigmented palms (lean and tanned) Nausa and pain Hypotension Salt cravings Loss of libido Tachycardia Postural dizziness Tearful
What are biochemical signs of adrenal insufficiency?
Hyponatramia Hypoglycaemia Hypercal Hyperkal Anaemia Eosinophilia Lymphocytosis Increased liver transaminases High TSH
What is management of adrenal insufficiecy?
Daily Hydrocortisone
Daily Fludrocortisone
Double doses when sick
What is the syacthen test?
syACTHen test- given synthetic ACTH and cortisol measured baseline, 30 and 60 mins after and cortisol response measured
What happens in an acute addisonian crisis?
Imbalance caused by vomit/diarrhoea, infection, surgery, MI, hypoglycaemia meaning acute lack of steroids
How does an addisonian crisi present/
Nausea Abdo pain Muscle cramps Confusion Hypotension Hyponat HyperK
How is an addisonian crisis managed?
IV HYDROCORTISONE bolus then infusion
Fluid resus
Correct glucose and monitor UandE
What is a phaemochromocytoma?
Adrenaline producing tumour of chromaffin cells in adrenals
How is adrenaline produced in phaeochromocytoma?
in bursts
WHat is phaeochromocytoma associated with?
Multiple Neuroendocrine Neopolasia (MEN 2)
Neurofibromatosis
What are clinical features of phaeochromocytoma?
HTN Palpitations Pallor Anxiety Tremor Sweating Weakness Fatigue Weight loss Hyperglycaemia
How is phaeochromocytoma investigated?
24 hour urine catecholamine collection and plasma metanephrine
CT/MRI
How is phaeochromocytoma managed?
BP control- alpha blocker (PHENOXYBENZAMINE) or CCBs then BBs once established on alpha blockers
Adrenalectomy with alpha blocker to prevent hypertensive crisis in theathre
What does Aldosterone do?
Causes increased sodium and water retention increasing BP
What does ADH do?
Increases absorbtion of sodium and water in the collecting ducts through the AQP-2 channels and therefore concentrating the urine
