Adrenal Disease

Question 1

What is Cushing’s syndrome?

Answer 1

A syndrome characterised by excess cortisol levels

Question 2

What are possible reasons for Cushing’s syndrome?

Answer 2

Iatrogenic
- drugs (glucocorditoids mimicking cortisol)

Primary Cushing’s
- cortisol producing adrenal tumour

Secondary Cushing’s (Cushing’s disease)
- Excess ACTH resulting in 2ry hyercortisolism
[] pituitary tumour
[] ACTH secreting ectopic tumour

Question 3

What are the symptoms associated with Cushing’s syndrome?

Answer 3

Cushingoid appearance
- Moon face, ‘Buffalo hump’, purple striae

Matabolic syndrome

• Central obesity with thin peripheries
• impaired glucose tolerance (pre hyperglycaemia)
• hyperlipidaemia
• hirsutism (abnormal growth of hair on lady’s face/body)

MSK

• Osteoporosis
• proximal myopathy
• avascular necrosis of femoral head

Immunosuppression

Psychiatric: insomnia, mania, depression

GI symptoms: increased risk of PUD, pancreatitis

Water retention => hypertension

Question 4

Which tests should be used to investigate Cushing’s?

Answer 4

To confirm: 24 hour urinary cortisol will be high

To differentiate:
- ACTH levels

• Dexamethasone (mimicks cortisol) suppression test
  [] low dose will suppress cortisol in normal
  [] high dose will suppress cortisol in pituitary tumours
  [] Won’t suppress cortisol in adrenal/ectopic tumours
• CT scan of adrenals
• MRI of pituitary
• Inferior petrosal venous sampling

Question 5

What is Conn’s syndrome?

Answer 5

Primary hyperaldosteronism
- i.e. not due to renin

• may be a result of:
  [] adrenal hyperplasia
  [] adrenal adenoma (2/3)
  [] adrenal carcinoma (very rare)

Question 6

What are the clinical findings of Conn’s syndrome?

Answer 6

Usually asymptomatic other than hypertension

• hypertension is often resistant to treatment
• hypokalaemia and hypernatraemia
• retinopathy

Question 7

Which investigations should be done for suspected Conn’s?

Answer 7

Bloods: ↓ [renin] plasma and ↓K+

CT adrenals - look for adenoma, hyperplasia, tumour

Adrenal venous sampling

Question 8

How should Conn’s syndrome be treated?

Answer 8

If possible unilateral adrenalectomy in unilateral adenoma

Aldosterone blockers (spironolactone)

Question 9

What is Addison’s?

Answer 9

Insufficicency of the adrenal gland

Question 10

What are the causes of Addison’s?

Answer 10

Acute

• sudden withdrawal of long term steroids
• adrenal haemorrhage

Chronic

• Autoimmune adrenalitis, i.e. Addison’s disease (most common cause, although still rare)
• Other primary incl. infection, adrenal mets, drugs
• Hypothalamic causes (v. rare) - tumour, trauma, radio-tx

Question 11

How do people with Addison’s present?

Answer 11

Often asymptomatic

Postural hypotension

Malaise, N&V

Addisonian crisis

• hypotension
• hypoglycaemia
• collapse
• sudden onset of leg/back/abdo pain

Pigmentation - only in primary causes

Associated Autoimmune disease e.g. DM, vitiligo, hypothyroidism

Question 12

What investigations are done for diagnosing adrenal deficiency?

Answer 12

Hyponatraemia and Hyperkalaemia due to mineralocorticoid deficiency

Hypoglycaemia due to cortisol deficiency

Decreased 9am cortisol but otherwise normal excludes hypoadrenalism
- in healthy, cortisol levels peak at 9am

Question 13

What investigations are done for differentiating between primary and secondary adrenal deficiency?

Answer 13

Short SynATCHen test

• IV ACTH given and measure cortisol levels 30mins and 60 mins and compare to baseline
• expect cortisol levels to increase if no primary problem

CT scan - to look for mets in adrenals

21-hydroxylase adrenal antibodies are +ve in >80% of autoimmune aetiologies

Question 14

How is adrenal deficiency treated?

Answer 14

Replacement of glucocorticoids and mineralocorticoids

• Hydrocortisone (glucocorticoid potent)
• Fludocortisone (mineralocorticoid potent)

Question 15

What is phaeochromocytoma (and paraganglioma)?

Answer 15

Tumour of the adrenal medulla (tumour of the sympathetic ganglion)
- 10% malignant, 10% familial

Result in excess catecholamine production

Question 16

What are the symptoms of phaeochromocytoma (and paraganglioma)?

Answer 16

Sweating
Tachycardia and hypertension
Weight loss
Increased blood glucose
High urinary catecholamines

Question 17

What investigations are done for phaeochromocytoma (and paraganglioma)?

Answer 17

24 hour urine collection - look for increased catecholamines and their metabolites

Imaging

Question 18

How is phaeochromocytoma (and paraganglioma) treated?

Answer 18

alpha-blockers and beta-blockers until surgery can be done

Surgery removed the phaeochromocytoma

Question 19

What is congenital adrenal hyperplasia?

Answer 19

Autosommal recessive condition characterised by an enzyme deficiency in the cortisol synthetic pathway.
- most commonly 21-hydroxylase deficiency

Low cortisol leads to increased ACTH secretion to maintain adequate cortisol which leads to hyperplasia

Diversion of steroid precursors into the androgenic steroid pathways occurs, thus 17-hydroxyprogesterone, androstenedione, and testosterone levels are increased resulting to virilisation

Question 20

What are the features of congenital adrenal hyperplasia?

Answer 20

Simple virilising form, sexual ambiguity, short stature

Salt wasting, hypotension, hyponatraemia

Impaired fertility

Question 21

How is congenital adrenal hyperplasia treated?

Answer 21

Corrective surgery

Mineralocorticoid and glucocorticoid replacement
i.e. fludrocortisone and hydrocortisone

Dexamethasone at night in adult, for treatment of hirsuitism

Question 22

What investigations are done for diagnosing congenital adrenal hyperplasia?

Answer 22

Measurement of adrenocortical hormones before and one hour after administration of ACTH
- increased DHEAS and androstenedione levels
- increased 17-hydroxyprogesterone levels
[] exagerated response to IV synacthen