Hyperfunction of adrenal glands

Question 1

what is a common endocrine cause of hypertension?

Answer 1

Primary hyperaldosteronism

unilateral adenoma
bilateral hyperplasia

Question 2

what are rarer ednocrine causes of hypertension?

Answer 2

Phaeochromcytoma
Cushing’s syndrome
Acromegaly
Hyperparathyroidism
Hypothyroidism
Congenital Adrenal hyperplasia

Question 3

what syndromes cause hypersecretion from the adrenal cortex?

Answer 3

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

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

Question 4

what syndromes cause hypersecretion from the adrenal medulla?

Answer 4

Phaeochromocytoma (catecholamines)

Question 5

what is cushings syndrome?

Answer 5

excess corticosteroids

Question 6

what type of hormone is cortisol?

Answer 6

catabolic hormone

Question 7

what effects does cortisol have on the body?

Answer 7

Tissue breakdown
causes weakness of skin, muscle & bone

Sodium retention
may cause hypertension & heart failure

Insulin antagonism
may cause diabetes mellitus

Question 8

what are side effects of glucocorticoid therapy?

Answer 8

Question 9

what are common characteristic features of cushings syndrome?

Answer 9

Question 10

what percentage of cases of cushings syndrome ACTH dependent?

Answer 10

75% cases:
Pituitary tumour (Cushing’s disease)

5% cases:
Ectopic ACTH secretion (eg lung carcinoid)

Question 11

what percentage of cases of cushings syndrome ACTH independent?

Answer 11

20% cases:
Adrenal tumour (adenoma or carcinoma)
Corticosteroid therapy (eg for asthma, IBD)

Question 12

describe the physiology of secondary hypersecretion due to a hypothalamic problem?

Answer 12

Question 13

describe the physiology of secondary hypersecretion due to a pituitary problem?

Answer 13

Question 14

describe the physiology of primary hypersecretion due to a problem with the adrenal cortex?

Answer 14

Question 15

what approach should be taken to diagmose hypercortisolism?

Answer 15

Question 16

what screening tests are done for cushings syndrome?

Answer 16

24 hr Urinary free cortisol:
normal 14- 135 nmol/24h

1mg overnight Dexamethasone suppression test taken at midnight
normal <50nmol/l (1.8 mg/dL) at 09.00h

Question 17

describe ACTH levels in the morning versus the evening in a normal patient?

Answer 17

Question 18

describe ACTH levels in the morning versus the evening in a patient with ectopic ACTH, adrenal cushings and pituitary ACTH?

Answer 18

Question 19

High dose dexamethasone test would show what in ectopic ACTH, pituitary dependent syndrome?

Answer 19

Question 20

what is treatment of choice to remove a pituitary tumour?

Answer 20

surgery

Question 21

what are medical treatments available for treatment of a pituitary tumour?

Answer 21

Adrenal hormone synthesis inhibitors
Ketoconazole
Metyrapone
Aminoglutethimide
Etomidate
Destroy Adrenocortical cells
Mitotane

Question 22

what are alternative treatment options for a pituitary tumour?

Answer 22

Radiotherapy
Bilateral Adrenalectomy

Question 23

breifly describe the renin-angiotensin-aldosterone system?

Answer 23

Question 24

describe the pathophysiology of primary hyperaldosteronism?

Answer 24

Question 25

how is primary hyperaldosteronism screened for?

Answer 25

Question 26

describethe screening tests for hyperaldosteronism?

Answer 26

Question 27

40-year-old woman
hypertension
hypokalaemia, K+ 2.7 mmol/l (N, 3.5-5)
plasma aldosterone 1135 pmol/l (N, 100-500)
plasma renin 1.8 (N, 2.8-4.5)
Diagnosis: primary hyperaldosteronism

How would she be managed?

Answer 27

conns syndrome

CT scan: 2cm left adrenal mass
iodocholesterol scan: increased uptake on the left
surgical removal of benign adenoma (mostly laparoscopically now)
post-op BP 120/80
no hypotensive drugs required