Clinical Aspects of the Adrenal Gland Clinical Case & Discussion

Question 1

what is the main cause of addisonse disease?

Answer 1

> 85% UK cases of adrenal failure

+ve adrenal autoantibodies (to 21-OHase) in 70% cases

Question 2

what are common symptoms associated with primary adrenal failure?

Answer 2

Weakness, fatigue, anorexia, weight loss 100%

Skin pigmentation or vitiligo 92%

Hypotension 88%

Unexplained vomiting or diarrhoea 56%

Salt Craving 19 %

Postural symptoms 12%

Question 3

what are possible clues to diagnosis of adrenal failure?

Answer 3

Disproportion between severity of illness & circulatory collapse / hypotension / dehydration

Unexplained hypoglycaemia

Other endocrine features (hypothyroidism, body hair loss, amenorrhoea)

Previous depression or weight loss

Question 4

what is the diagnosis of adrenal insufficiency?

Answer 4

Routine bloods: U&E, glucose, FBC

Random cortisol
>550 nmol/l (not Addison’s)
<500 nmol/l (adrenal status uncertain)

Synacthen test (and basal ACTH)
If suspicion high & patient unwell, treat with steroids and do Synacthen test later

Question 5

what is the mineralocorticoid replacement?

Answer 5

Synthetic steroid, fludrocortisone

Binds to mineralocorticoid (aldosterone) receptors

Question 6

in regards to stress and steroids, who needs special care?

Answer 6

Hypoadrenal patients on replacement steroids
Patients on steroids in doses sufficient to suppress the pituitary adrenal axis (>7.5mg prednisolone daily, or equivalent)
Patients who have received such treatment during the previous 18/12 (HPA axis may still be suppressed)

Question 7

what action should be taken in regardsto stress and steroids?

Answer 7

Minor short-lived illness or stress
double glucocorticoid dose
Major illness or operation
(especially if nil by mouth or GI upset)
100mg hydrocortisone iv stat
50-100mg HC iv 8-hourly
as stress abates, reduce HC by 50% per day until back on usual replacement dose

Question 8

what are the three important self care rules for patients on steroids?

Answer 8

Never miss steroid doses
2. Double the hydrocortisone dose in event of intercurrent illness (eg flu, UTI)
3. If severe vomiting or diarrhoea, call for help without delay
(likely to need IM hydrocortisone - some patients or their partners are taught to inject)

Question 9

what are the endocrine causes of hypertension?

Answer 9

Primary hyperaldosteronism
unilateral adenoma
bilateral hyperplasia

Rarer causes
Phaeochromcytoma
Cushing’s syndrome
Acromegaly
Hyperparathyroidism
Hypothyroidism
Congenital Adrenal hyperplasia

Question 10

what are adrenal disorders hyper secretion?

Answer 10

Cortex
Cushing’s syndrome (cortisol, androgens) (adenoma, carcinoma or bilateral hyperplasia)

Conn’s syndrome (aldosterone) (adenoma or bilateral hyperplasia)

Medulla
Phaeochromocytoma (catecholamines)

Question 11

what are the investigations of hypercortisolism?

Answer 11

overnight dex test, 24hr urine free cortisol

low dose dex text

paired morn-midnight ACTH cortisol

high dose dex test

MRI sella
CT adrenal
BIPSS
CT chest

Question 12

what causes congenital adrenal hyperplasia?

Answer 12

> 90% cases due to 21-hydroxylase deficiency