Endocrinology

Question 1

Nelson’s syndrome

Answer 1

Post-bilateral adrenalectomy (for Cushing’s)

Hyperpigmentation + enlargement of corticotroph adenoma

Question 2

Kallmann’s syndrome

Answer 2

Isolated hypogonadotrophic hypogonadism

Anosmic/hyposmic
Colour blindness
Midline facial developmental defects

Question 3

Anaplastic carcinoma of the thyroid

Answer 3

Elderly, worst prognosis, early mets

Large hard mass w/ irregular borders

Pain, stridor, laryngeal nerve palsy

NORMAL TFTs

Question 4

Prolactin cutoff for micro/macroadenoma

Answer 4

> 2000 mU/L

Question 5

Adrenal carcinoma

Answer 5

Elevated cortisol + undetectable ACTH = adrenal adenoma/carcinoma

Acute Hx + severe virilisation suggests CARCINOMA

Question 6

Addison’s disease

Answer 6

Any form of primary hypoadrenalism

Women, autoimmune

Plasma ACTH is HIGH, HYPOnatraemia, HYPERkalaemia, uraemia

Synacthen test = FAILURE of cortisol secretion

Question 7

Ectopic ACTH secretion

Answer 7

Plasma ACTH +++ (>400)
Absolute failure to produce cortisol (HIGH-dose dexamethasone)

Weight GAIN = small bronchial carcinoid tumour

Weight LOSS + hypokalaemic alkalosis = small-cell bronchial carcinoma

Question 8

Cushing’s disease

Answer 8

The usual symptoms etc

Suppression of serum cortisol on HIGH-dose dexamethasone only!

Failure to respond to low-dose dexamethasone, loss of diurnal variation of cortisol secretion, loss to cortisol respones with an INSULIN TOLERANCE test

Question 9

Pseudo-Cushing’s

Answer 9

Body habitus of Cushing’s, elevated MCV, elevated GGT, alcoholic

Suppresses cortisol with LOW-dose dexamethasone

Diurnal variation in cortisol on blood samples

Question 10

Long term steroids presents with HYPONATRAEMIA - diagnosis?

Answer 10

Addison’s disease

Question 11

Patiently with newly diagnosed T2DM with minimal symptoms - management?

Answer 11

Dietary and lifestyle advice

Question 12

OVERWEIGHT patient with T2DM not responding to dietary and lifestyle advice - management?

Answer 12

Metform

BEWARE lactic acidosis

Question 13

NORMAL WEIGHT patient with T2DM not responding to dietary and lifestyle advice - management?

Answer 13

Gliclazide (sulphonylurea)

Question 14

Patient is on one oral diabetes medicine but they are not responding - what is the next appropriate step in management?

Answer 14

Add the other agent

If contraindicated (excess ETOH, renal/hepatic impairment/???overweight)

Question 15

T2DM is not responding to maximal oral diabetic management - what is the nxt appropriate step in management?

Answer 15

INSULIN (twice daily or once daily nighttime)

Question 16

What hormone is increased in premature ovarian failure?

Answer 16

FSH

Question 17

Hypoparathyroidism

Answer 17

HIGH phosphate + LOW calcium

Causes = thyroidectomy

Question 18

Primary hyperparathyroidism

Answer 18

Lethargy, polyuria, polydipsia, PUD, stone formation, depression (+++Ca = cardiac arrest)

HIGH calcium + LOW phosphate

Treatment = parathyroidectomy

Question 19

Secondary hyperparathyroidism

Answer 19

Secondary to chronic renail failure –> hyperphosphataemia = reduced Vit D = chronic hypocalcaemia = INCREASED PTH

Complications = osteodystrophy, bone pain, osteomalacia, pathological #

Question 20

Tertiary hyperparathyroidism

Answer 20

Prolonged period of secondary hyperparathyroidism –> gland hypertrophy

HIGH phosphate + HIGH calcium

Question 21

What kind of hormone is secreted by small cell malignancy tumours that causes hypercalcaemia?

Answer 21

Ectopic PTH-RELATED protein

Question 22

Paget’s disease of the bone

Epidemiology

Answer 22

Eldery

M:F = ~1

Question 23

Paget’s disease of the bone

Presentation

Answer 23

Boney pain (esp. in pelvis/lumbar region)

Bitemporal skull enlargement with frontal bossing
Spinal kyphosis
Anterolateral bowing of limbs

Fractures
Heat (inc. vascularity)
Sensorineural deafness)

Cardiac failure, gout

Question 24

Paget’s disease of the bone

Investigation

Answer 24

***SINGLE BEST = Bone radiographs

Bloods = ++ AlkPhos with normal calcium/phosphate

Question 25

MEN I syndrome

Answer 25

Wermer's syndrome A) Pituitary tumour --> prolactinoma / increased GH --> galactorrhoea, acromegaly, visual field defects, headaches B) Parathyroid tumour --> increased PTH --> increased calcium --> nephrolithiasis C) Pancreastic tumour --> gastrinoma (PUD) / insulinoma (hypoglycaemia) / VIPoma (diarrhoea / 2^ electrolyte disturbance) ******CT / MRI to visualise tumours

Question 26

MEN IIa syndrome

Answer 26

Sipple's syndrome A) Medullary thyroid carcinoma --> nodular mass in neck B) Parathyroid tumour --> increased PTH --> increased calcium --> nephrolithiasis C) Phaeochromocytoma (adrenal medullary tumour) --> increased adrenaline/noradrenaline --> +++ paroxysmal sympathetic outburts (increased BP, anxiety, palpitations, headache, sweating) ******CT / MRI to visualise tumours

Question 27

MEN IIb/III

Answer 27

A) Medullary thyroid carcinoma --> nodular mass in neck B) Phaeochromocytoma --> increased catecholamines --> +++ paroxysmal sympathetic outbursts (increased BP, anxiety, palpitations, headache, swearing) C) Mucosal neuromas D) Marfanoid body habitus ******CT/MRI to visualise tumours

Question 28

PCOS

Answer 28

THREE diagnostic criteria --> 2+ cysts on US pelvis >10mm / hirsutism / amenorrhoea Insulin resistance --> weight gain / obesity Infertility ******US pelvis = BEST investigation ***Bloods = + testosterone, ++ LH, + FSH, +++ LH:FSH ratio (~3)

Question 29

Cranial diabetes insipidus

Answer 29

Failure to produce ADH (vasopression) Polyuria and polydipsia Plasma osmolality HIGH, urine osmolality LOW, HYPERnatraemia ******WATER DEPRIVATION TEST --> no change ***Give vasopressin --> osmolalities stabilise TREATMENT = DESMOPRESSIN

Question 30

Nephrogenic diabetes insipidus

Answer 30

Failure to produce ADH (vasopression) Polyuria and polydipsia Plasma osmolality HIGH, urine osmolality LOW, HYPERnatraemia ******WATER DEPRIVATION TEST --> no change ***Give vasopressin --> no change TREATMENT = DESMOPRESSIN

Question 31

T2DM patient is on maximum dose of metformin but is allergic to sulfonyureas - next appropriate management?

Answer 31

MEGLITINIDE, e.g. repaglinide

Question 32

Hyperosmolar non-ketotic coma - first management?

Answer 32

Insulin infusion at 3U/hour (sliding scale)

Question 33

Which three biochemical abnormalities are diagnostic of DKA?

Answer 33

Ketonaemia >3 or ketonuria ++ Blood glucose >11 or known DM HCO3 <15 +/- venous pH <7.3

Question 34

How is DKA managed?

Answer 34

Involve specialist diabetes team + monitor using VBG FRIII at 0.1U/kg/hr (eg 7U/hr for 70kg patient) Do NOT give bicarbonate Give potassium if <5.5 0.9%NaCL 1L over 1 hour (then with KCl if needed) If BP <90 systolic, fluid challenge 500ml 0.9%NaCl

Question 35

What is used to diagnose HHS (hyperosmolar hyperglycaemic state)?

Answer 35

Hypovolaemia Marked hyperglycaemia (>30mmol/L) No significant ketonaemia/acidosis Osmolality usually >320

Question 36

How is HHS managed?

Answer 36

0.9%NaCl while measuring osmolality Give insulin with significant ketonaemia (>1) at 0.05U/kg/hr (HALF of DKA) Replace potassium if <5.5 LMWH --> anticoagulation Correct U+Es

Question 37

Which is the MOST COMMON thyroid cancer?

Answer 37

Papillary