Adrenal Disease

Question 1

Difference between primary and secondary hypoadrenocorticalism?

Answer 1

Primary: complete destruction of AC. Cortisol, aldosterone and sex hormones low
Secondary: Change in ACTH release. aldosterone levels are maintained since it is stimulated by angiotensin II rather than ACTH.

Question 2

What is adrenalitis ?

Answer 2

Autoimmunity, with 21-hydroxylase acting as the autoantigen.
Other causes including TB, surgery, Ca and HIV/AIDs.

Question 3

Defining features of Addison’s ? What are their nutritional deficiencies ?
high or low potassium?

Answer 3

pigmentation, postural hypotension and syncope
tiredness
adensonion crisis precipitated by trauma, surgery or illness.

salt, glucose
hyperkalaemia

Question 4

Diagnostic test for addison’s?

Answer 4

A short ACTH stimulation test is of value, in normality giving tetracosactide (Synacthen) should stimulate cortisol >600 at 30 minutes. This will not occur in patients with hypoadrenocorticolism.

Test may be requested in Addison’s disease where the concentrations of this hormone in the bloodstream are usually high. In such patients a synacthen test (stimulation test) should be carried out

Question 5

Difference between Cushnig’s disease and syndrome?

Answer 5

Cushing’s disease is caused by pituitary gland hypersecretion of ACTH.
Cushing’s syndrome however may be caused by ectopic ACTH secreting tumours (such as small cell carcinoma of the lung or RCC kidney), adrenal adenomas, glucocorticoid administration or ACTH administration. Alcohol and depression may induce pseudo-Cushing’s syndrome.

Question 6

Signs of Cushings?

Answer 6

Signs include thin skin, bruising, moon face, plethora, striae, proximal myopathy (lemon on sticks), hypertension, pathological fractures and buffalo hump.
Most obese, hirsute, hypertensive patients do not have Cushing’s syndrome/disease.

Question 7

Diagnostic tests for Cushings?

Answer 7

Confirmation of diagnosis is performed by observing inappropriate cortisol secretion.
􏰀 Low dose DEXA (0.5mg 6 hourly) suppression tests will suppress adrenal tumour output.
􏰀 High dose DEXA suppression testing (2mg 6 hourly) will differentiate between pituitary and
ectopic sources. Pituitary ACTH output will be inhibited but ectopic ACTH output will not.