Endocrinology

Question 1

Management nephrogenic diabetes insipidus

Answer 1

thiazides

low salt and protein diet

Question 2

Management central diabetes insipidus

Answer 2

desmopressin

Question 3

define cranial diabetes insipidus

Answer 3

deficiency of ADH

Question 4

define nephrogenic diabetes insipidus

Answer 4

insensitivity to ADH

Question 5

Causes of cranial diabetes insipidus

Answer 5

• idiopathic
• head injury
• pituitary surgery
• craniopharyngioma
• histocytosis X
• DIDMOAD - DI + DM + Optic atrophy + deafness = Wolfram’s syndrome
• haemochromatosis

Question 6

Causes of nephrogenic diabetes insipidus

Answer 6

• genetic
• electrolytes imbalance (hypercalcaemia, hypokalaemia)
• drugs (demeclocycline, lithium)
• tubulo-interstitial disease (obstruction, sickle cell, pyelonephritis)

Question 7

Fts of diabetes insipidus

Answer 7

polyuria

polydipsia

Question 8

Investigation + result in diabetes insipidus

Answer 8

• high plasma osmolality
• low urine osmolality (<700)
• water deprivation test (12hrs no water + vasopressin - if response it is central DI)

Question 9

1st line management of T2DM

Answer 9

diet and lifestyle advice

Question 10

single drug manaement T2DM

Answer 10

metformin

if CI =
- if CVD established/risk orCHF = SGLT-2i
- otherwise = any other

Question 11

Troubleshooting intolerance to metformin

Answer 11

• titrate up slowly
• trial MR

Question 12

When to use GLP-1 mimentic (i.e semaglutide/ozempic)

Answer 12

does not achieve HbA1c control on dual drug therapy AND
- BMI >35
- BMI <35 but insulin would have implications/weight loss would benefit comorbidities

AND only continued if reduction of at leasr 11mmol/mol AND weight loss 3% in 6mo

NOT additional to insulin unless under specialist care

Question 13

when to start 3rd line management T2DM

Answer 13

if HbA1c >58mmol/mol + with lifestyle advice and one drug

Question 14

Second drug management T2DM

Answer 14

• if high risk/established CVD or HF - SGLT-2 inhibitor
• • sulfonylurea if no risk of hypoglycaemia
• DPP4-i or thiazolidindedione if at risk of hypoglycaemia

Question 15

target HbA1c if on lifestyle + sulfonylurea

Answer 15

53

Question 16

target HbA1c if on one drug but HbA1c has rised to 58mmol/mol

Answer 16

53mmol/mol

Question 17

target HbA1c if on lifestyle + one drug (excluding sulfonylurea)

Answer 17

48mmol/mol

Question 18

Typical blood findings seen along with Cushing’s syndrome

Answer 18

hypokalaemic metabolic alkalosis (esp a/w ectopic ACTH in SCC)

impaired glucose tolerance

Question 19

3 most common tests used to confirm Cushing’s syndrome

Answer 19

• overnight (low-dose) dexamethasone suppression = most sensitive; positive = no cortisol spike in am
• 24hr urinary free cortisol (2 measurements)
• bedtime salivary cortisol 2 measuremetns required)

Question 20

Localizing tests for Cushing’s syndrome
1. fist line test
2. interpretation

Answer 20

1. 9am and midnight plastma ACTH (and cortisol)
2. ACTH suppressed = non-ACTH dependent cause (i.e adrenal adenoma)

Question 21

Localizing tests for Cushing’s syndrome
1. second line test
2. interpretation

Answer 21

1. High dose dexamethasone supression test
2. • cortisol not supp BUT ACTH supp = non-ACTH dependent (o.e adrenal adenoma)
   • cortisol AND ACTH supp = Cushing’s disease (pituitary adenoma)
   • cortisol AND ACTH not supp = ectopic ACTH

Question 22

investigations for suspected Addison’s disease
1. in GP
2.2nd line GP/hospital

Answer 22

1. 9am serum cortisol (if >500 Addison very unlikely)
2. ACTH simulation (short Synacthen test) = plasma cortsol before and 30 mins after giving Synachen 250ug IM

Question 23

associated electrolyte abnromalities with Addison’s disease (undiagnosed)

Answer 23

hyperkalaemia
hyponatraemia
hypoglycaemia
metabolic acidosis