endocrine

Question 1

define pcos

Answer 1

characterised by oligo/amenorrhoea and hyperadrogenism

Question 2

risk factors for pcos

Answer 2

environmental factors
genetic variants
hyperinsulinaemia (leads to increased ovarian androgen synthesis and reduced hepatic sex hormone binding globulin synthesis = increase in free androgens)

Question 3

epidemiology of pcos

Answer 3

most common cause of infertility

Question 4

presenting symptoms of pcos

Answer 4

menstrual irregularities 
hirsutism
male pattern hair loss 
acne 
dysfunctional uterine bleeding

Question 5

signs of pcos

Answer 5

hirsutism
male pattern hair loss
acne
acanthosis nigricans (severe insulin resistance) - velvety thickening and hyper pigmentation of axilla or neck

Question 6

investigations for pcos

Answer 6

bloods:
- high LH
- high LH: FSH ratio
- high testosterone, androstenedione and DHEA-s
- low SHBG

test for:
hyperprolactinaemia, hypo/hyperthyroidism, CAH (17OH prog levels), cushings

impaired glucose tolerance tests:
fasting blood glucose
hb1ac
fasting lipids

Question 7

Define primary hyperaldosteronism

Answer 7

Characterised by autonomous aldosterone overproduction from the adrenal gland with subsequent suppression of plasma renin activity

Question 8

risk factors of primary hyperaldosteronism

Answer 8

•Adrenal adenoma (Conn’s syndrome) - responsible for 70% of cases
•Adrenal cortex hyperplasia (30% of cases)
RARE:
Glucocorticoid-suppressible hyperaldosteronism
Aldosterone producing adrenal carcinoma

Question 9

pathophysiology of primary hyperalosteronism

Answer 9

Excess aldosterone leads to increased Na+ and water retention
This leads to hypertension
It also causes increased renal K+ loss leading to hypokalaemia
Renin is suppressed due to NaCl retention

Question 10

epidemiology of primary hyperaldosteronism

Answer 10

•Conn’s syndrome is more common in WOMEN and YOUNG patients
•Bilateral adrenal hyperplasia is more common in MEN and presents at an older age

Question 11

presenting symptoms of primary hyperaldosteronism

Answer 11

• Usually ASYMPTOMATIC
• Tends to be an incidental finding on routine blood tests

Symptoms of Hypokalaemia:
    o	Muscle weakness 
    o	Polyuria and polydipsia (due to nephrogenic DI)
    o	Paraesthesia
    o	Tetany

Question 12

signs of primary hyperaldosteronism

Answer 12

Hypertension

Complications of hypertension (e.g. hypertensive retinopathy)

Question 13

screening investigations for primary hyperaldosteronism

Answer 13

• Low Serum K+
  NOTE: Serum Na+ is usually normal because the Na+ reabsorption is matched by water reabsorption
  o High Urine K+
  o High Plasma Aldosterone Concentration
  o High aldosterone: renin activity ratio

Question 14

confirmatory tests for primary hyperaldosteronism

Answer 14

oSalt Loading (Failure of aldosterone suppression following salt load confirms primary hyperaldosteronism)

Postural Test (Measure plasma aldosterone, renin activity and cortisol when the patient is lying down at 8 am 
- Measure again after 4 hrs of the patient being upright 
- Aldosterone-producing adenoma - aldosterone secretion decreases between 8 am and noon
•Bilateral adrenal hyperplasia - adrenals respond to standing posture and increase renin production leading to increased aldosterone secretion 

oCT/MRI
oBilateral adrenal vein catheterisation
• Measures adrenal vein aldosterone levels and allows you to distinguish between Conn’s syndrome and bilateral adrenal hyperplasia

oRadio-labelled cholesterol scanning
•Unilateral uptake in adrenal adenomas
•Bilateral uptake in bilateral adrenal hyperplasia

Question 15

management plan for primary hyperaldosteronism

Answer 15

Bilateral Adrenal Hyperplasia
o Spironolactone
o Eplerenone can be used if the spironolactone side-effects are intolerable
o Amiloride (potassium-sparing diuretic)
o Monitor serum K+, creatinine and BP
o ACE inhibitors and CCBs may also be added

Aldosterone Producing Adenomas
o Adrenalectomy

Adrenal Carcinoma
o Surgery
o Post-operative mitotane (antineoplastic)

Question 16

complications of primary hyperaldosteronism

Answer 16

hypertension complications

Question 17

Summarise the prognosis for patients with primary hyperaldosteronism

Answer 17

Surgery may cure hypertension

Or it may make the hypertension easier to treat with anti-hypertensive medication