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Question 1

Shock, unresponsive to fluid boluses

Inotropic support:
Noradrenaline or dobutamine?

Answer 1

Noradrenaline
Acts on both alpha and beta adrenergic receptors, thus stimulates the heart and improves BP

NOT dobutamine
Acts selectively on beta receptors, thus stimulating the heart but causing vasodilation as well, worsening hypotension

Question 2

B12 (cobalamin) or folate?

Which one do you fix first?

Answer 2

B12 must be investigated before administering folate.

Otherwise there is a risk of masking a B12 deficiency and causing neuropathy and/or dementia

Question 3

Most common site of acute mesenteric ishaemia due to arterial thrombosis?

Answer 3

SMA

Question 4

Nephrotic Syndrome

Three features

Answer 4

1. Proteinuria of >= 3.5 g/24h
2. Hypoalbuminaemia of =<30 g/L
3. Oedema
   Also, hyperlipidaemia and thrombosis

Question 5

Myotonic dystrophy: ECG changes

Answer 5

Mild to moderate disease:
First-degree AV block
Left anterior hemiblock (LAD without strain pattern)

Severe:
AF / flutter
abnormal Q waves
ST and/or T wave abnormalities

Question 6

Gold-top tube

Additive and use

Answer 6

Nothing/clotting agent/ gel
(the serum is of interest; additives can cause cells to clot and separate to the bottom)

Chemistry, serology and immunology
Troponin

Question 7

Purple-top tube

Additive and use

Answer 7

Potassium and EDTA
(chalates calcium and prevents clotting)

FBC
ESR
HbA1c

Question 8

Blue-top tube

Additive and use

Answer 8

Sodium citrate
(binds calcium and prevents coagulation)

Clotting
INR
D-dimer

Question 9

Grey-top tube

Additive and use

Answer 9

Sodium fluoride
(inhibits glycolysis)

blood glucose
blood alcohol
lactate

Question 10

1st line investigation for narcolepsy?

Answer 10

Multiple sleep latency EEGs

Question 11

Contraindications to starting statins?

Answer 11

Pregnancy

Macrolides

Question 12

Indications for statins?

3

Answer 12

Secondary prevention
QRISK >10%
T1DM for 10+ years

Question 13

Which structure is cut in surgery for carpal tunnel syndrome?

Answer 13

Flexor retinaculum

Question 14

Carpal tunnel syndrome: on examination (4)

Answer 14

Thenar wasting
Weak thumb abduction (abductor pollicis brevis)
Tinnel’s sign
Phalen’s sign

Question 15

Open-angle glaucoma: medications and mechanisms

Answer 15

Latanoprost
prostaglandin analogue leading to increased outflow

Timolol
beta blocker leading to decreased aqueous production

Alpha2-agonists

Question 16

MODY

epidemiology
mutation
treatment

Answer 16

Young (<25 years)
T2DM, ie not presenting with ketosis
Family history (autosomal dominant)

hepatic nuclear factor (HNF 1 alpha) is most common mutation

Sulphonylureas for best response
(since the mutation causes decreased insulin secretion and/or release)

Question 17

Intrauterine device (IUD) for contraception:
when to administer

Answer 17

Up to 5 days after intercourse
OR
Up to 5 days after estimated ovulation

HENCE: can give more than 5 days after last intercourse

Question 18

Meniere’s disease: Treatment

Answer 18

Acute = buccal or IM prochlorperazine
Prophylactic = betahisitine

Question 19

Pyrexia of Unknown Origin (PUO)

Answer 19

Fever of more than 3 weeks

Malignancy
lymphoma, nephroma, leukaemia, or atrial myxoma

Infection
tuberculosis
abscess

Question 20

Congenital adrenal hyperplasia mechanism

Answer 20

Autosomal recessive mutation
21-hydroxylase deficiency

Build up of 17-hydroxyprogesterone
AND
low cortisol

Increased ACTH secretion leading to hyperaldosteronism and raised sex steroids (thus virilization in females)

Question 21

Otosclerosis: pathophysiology

Answer 21

Autosomal dominant mutation (FHx)
Typically 20-40y

Normal bone is replaced by vascular spongy bone (may cause ‘flamingo tinge’ on otoscopy)

Progressive conductive hearing loss as stapes fuses at oval window

Question 22

Conjugate eye deviation in stroke:

Ipsi or contralateral?

Answer 22

Ipsilateral

R hemisphere innervates L lateral rectus and R medial rectus
Thus, lesions on R cause unopposed action of R lateral rectus and L medial rectus

Question 23

Wellens Syndrome

Answer 23

Deep inverted or biphasic T waves in V2-3
Patient may be pain free at presentation
Cardiac markers may be (still) normal

Critical LAD stenosis

Poor response to Rx
High risk of LAD occlusion
Need surgery

Question 24

Schistosomiasis treatment

Answer 24

Praziquantel
Increases capillary permeability to Ca2+
Thus, parasite paralysis
80% cure rate

Question 25

Blunt Aortic Injury on CXR (5)

Answer 25

Widened mediastinum 
Indistinct aortic knob
Abnormal aortic contour
Pleaural blood above left apex (apical capping)
Displaced left main bronchus 

NB: Not pathognomonic, thus further testing needed

Question 26

Vitamin B12 injections - route?

Answer 26

IM or SC (not PO before excluding malabsorption)

IV would not be retained (lost in urine due to water-solubility)

Question 27

FAST scan value

Answer 27

Can confirm intrabdominal bleeding, but cannot exclude it!

Thus, further tests if suspicion present and negative FAST scan

Question 28

Necrobiosis lipoidica

Answer 28

Diabetics (5%)
Usually on both shins
Starts off as a “burn”
Very tender + ulcerates easily with trauma

Question 29

Chronic mesenteric ischaemia: investigation of choice?

Answer 29

Arteriography (with subsequent endovascular revascularization)

Vasculopaths
Postprandial pain + fear of eating

Question 30

Eruptive seborrhoeic keratoses: association?

Answer 30

Leser-Trelat sign in malignancy (ex gastric cancer)

? Cytokine release from cancer stimulates keratotic growth
Resolves in 50% of cases with treatment of underlying cause

Question 31

Carbamazepine cautions (2)

Answer 31

1. LFTs monitoring

2. HLA-B*1502 antigen (SE Asia) increases risk of toxic epidermal necrolysis