Addison's

Question 1

Define Addison’s disease

Answer 1

Deficiency of adrenal cortical hormones i.e. mineralocorticoids, glucocorticoids and androgens

Question 2

Aetiology of Addison’s disease

Answer 2

Primary: Addison’s disease = autoimmune (>70%)*
Infections: TB, meningococcal septicaemia (waterhouse-Friderichsen syndrome**), CMV (HIV patients), histoplasmosis
Infiltration: Metastasis e.g. lung, breast, melanoma, lymphomas, amyloidosis
Infarction: thrombophilia
Inherited: Adrenoleukodystrophy, ACTH receptor mutation, congenital adrenal hyperplasia
Surgical: After bilateral adrenalectomy
Secondary: pituitary or hypothalamic disease
Iatrogenic: Sudden cessation of long-term steroid therapy

*90% of the adrenal cortex needs to be destroyed to produce adrenal insufficiency. 80-90% are autoimmune, with Abs against the adrenal cortex and/or 21-hydroxylase.
**Adrenal failure due to bleeding into the glands, commonly caused by N. meningitis infection in the past

Question 3

Symptoms of Addison’s disease

Answer 3

Dizziness
Anorexia
Weight loss
Diarrhoea
Vomiting
Abdominal pain
Lethargy
Weakness
Depression

Question 4

Signs of addison’s disease on examination

Answer 4

Postural hypotension
Skin hyperpigmentation - noticeable on buccal mucosa, scars, skin creases, nails, pressure points (Primary only)
Loss of body hair in women
Associated autoimmune conditions e.g. vitiligo

Question 5

Investigations for addison’s disease

Answer 5

UOsm/sodium: raised

U&Es: hyperkalaemia and hyponatraemia
Cortisol: 9am <100nmol/L
Short Synacthen test: Cortisol <550nmol/L
Long synacthen test: no increase in cortisol
Autoantibodies: positive
FBC: neutrophilia
VBG/ABG: metabolic acidosis
Bone profile: Raised calcium
Glucose: hypoglycaemia (esp. in crisis)

Abdo CT/MRI: wasted adrenal glands

Question 6

What is the management for addison’s disease

Answer 6

1. Replace glucocorticoids with hydrocortisone (3x a day) and mineralocorticoids with fludrocortisone
2. Must increase hydrocortisone dose during acute illness or stress
3. WITH hypothyroidism - give hydrocortisone BEFORE thyroxine
4. Give steroid warning card, medic-alert bracelet, emergency hydrocortisone

Question 7

Prognosis for addison’s disease

Answer 7

Adrenal function will rarely recover, but normal life expectancy can be expected with treatment

Question 8

What is an addisonian crisis

Answer 8

Acute adrenal insufficiency with major haemodynamic collapse, often precipitated by stress

Question 9

Symptoms and signs of addisonian crisis

Answer 9

Syncope (BP)
Dehydration (vomiting and diarrhoea)
Hypoglycaemia
Confusion and seizures (electrolyte)

Signs: hypotensive shock, tachycardia, pale, cold, clammy, oliguria

Question 10

Management for addisonian crisis

Answer 10

1. Rapid IV fluid rehydration (0.9% saline, 1L over 30-60 minutes)
2. 50ml of 50% dextrose
3. Hydrocortisone 200mg IV bolus followed by 100mg 6 hourly (100mg IV followed up 200mg IV 24h?)
4. Treat any underlying cause
5. Monitor

+ medicalert bracelet for steroid dependence

Question 11

What is polyglandular autoimmune syndrome type II (Schmidt’s syndrome), what causes it, and what are the clinical features

Answer 11

Addison’s disease + primary hypothyroidism

Autoimmune nature of both diseases - Abs against both the thyroid and adrenal glands

Primary hypothyroidism + hypoglycaemia (glucocorticoid deficiency) + hyperkalaemia/hyponatraemia (Addison’s)