AMC CAT MCQ Exam — Questions and Answers

Question 1: Which finding on arterial blood gas is most concerning in an acute severe asthma attack?

A mild respiratory alkalosis
A low PaCO2
A high PaO2
A normal or rising PaCO2 (Correct answer)

Correct answer: A normal or rising PaCO2

A normalising or rising PaCO2 signals tiring respiratory muscles and impending respiratory failure.

Question 2: What is the most reliable clinical sign of established compartment syndrome in a limb?

Absent distal pulses early
Reduced capillary refill alone
Pain on passive stretch out of proportion to injury (Correct answer)
Skin pallor only

Correct answer: Pain on passive stretch out of proportion to injury

Pain on passive stretch is the earliest and most reliable sign; pulselessness is a late finding.

Question 3: A 70-year-old man has a resting tremor, bradykinesia and cogwheel rigidity that began on one side. What is the most likely diagnosis?

Benign physiological tremor
Essential tremor
Cerebellar tremor
Idiopathic Parkinson's disease (Correct answer)

Correct answer: Idiopathic Parkinson's disease

Asymmetric resting tremor with bradykinesia and rigidity is the classic triad of idiopathic Parkinson's disease.

Question 4: A 55-year-old man presents with sudden severe pain, redness and swelling of the first metatarsophalangeal joint. What is the most likely diagnosis?

Osteoarthritis
Septic arthritis
Acute gout (Correct answer)
Rheumatoid arthritis

Correct answer: Acute gout

Acute podagra of the first MTP joint with rapid onset is classic for gout.

Question 5: A 48-year-old man presents with severe epigastric pain radiating to his back, associated with nausea and vomiting. His serum lipase is markedly elevated. An ultrasound reveals gallstones in the gallbladder but no common bile duct dilatation. He is diagnosed with mild, gallstone-induced pancreatitis. His symptoms resolve with conservative management. What is the most appropriate next step to prevent recurrence?

Discharge with a low-fat diet and follow-up in 6 months.
Ursodeoxycholic acid therapy.
Endoscopic retrograde cholangiopancreatography (ERCP) with sphincterotomy.
Laparoscopic cholecystectomy during the same hospital admission. (Correct answer)

Correct answer: Laparoscopic cholecystectomy during the same hospital admission.

For patients with mild biliary pancreatitis, guidelines recommend performing a laparoscopic cholecystectomy during the index (same) hospital admission once the pancreatitis has resolved. This is to prevent recurrent attacks of pancreatitis, which are common if the gallbladder is left in situ. Delaying surgery increases the risk of recurrence. ERCP is indicated for concurrent cholangitis or confirmed common bile duct stones, not for uncomplicated gallstone pancreatitis. Dietary advice is important but not sufficient to prevent recurrence.

Question 6: A 22-year-old presents with foot drop and weakness of ankle dorsiflexion after sitting cross-legged for a prolonged period. Which nerve is most likely affected?

Femoral nerve
Common peroneal (fibular) nerve (Correct answer)
Sciatic nerve
Tibial nerve

Correct answer: Common peroneal (fibular) nerve

Compression of the common peroneal nerve at the fibular head causes foot drop and impaired dorsiflexion.

Question 7: A 72-year-old man with a known history of severe COPD is brought to the hospital with increased breathlessness, wheeze, and purulent sputum. He appears drowsy. His initial oxygen saturation on room air is 86%. According to the Thoracic Society of Australia and New Zealand (TSANZ) guidelines for acute oxygen use, what is the recommended target oxygen saturation (SpO2) range for this patient?

92-96%
94-98%
88-92% (Correct answer)
Above 98%

Correct answer: 88-92%

In patients with COPD and other conditions associated with chronic respiratory failure, there is a risk of worsening hypercapnia if excessive oxygen is administered. The Thoracic Society of Australia and New Zealand (TSANZ) guidelines recommend titrating oxygen to a target SpO2 range of 88–92% for these patients. This approach minimises the risk of suppressing the hypoxic respiratory drive and worsening respiratory acidosis, while still providing adequate oxygenation. The higher target of 92-96% is for patients without chronic respiratory failure.

Question 8: According to the National Bowel Cancer Screening Program in Australia, what is the recommended screening method and interval for an asymptomatic 55-year-old person at average risk of colorectal cancer?

Flexible sigmoidoscopy every 5 years.
Biennial immunochemical faecal occult blood test (iFOBT). (Correct answer)
Colonoscopy every 10 years.
Annual immunochemical faecal occult blood test (iFOBT).

Correct answer: Biennial immunochemical faecal occult blood test (iFOBT).

The current Australian National Bowel Cancer Screening Program recommends biennial (every two years) screening with an immunochemical faecal occult blood test (iFOBT) for asymptomatic people at average risk, starting from age 50 and continuing to age 74. Recent guideline updates also support starting iFOBT screening from age 45. Colonoscopy is the investigation for a positive iFOBT or for those at higher risk, not for primary screening in the average-risk population.

Question 9: A patient requests a treatment that you believe is not clinically indicated and may cause harm. What should you do?

Provide it because the patient is autonomous
Provide it but document your objection
Decline to provide non-beneficial or harmful treatment while explaining your reasoning and alternatives (Correct answer)
Refer them away without explanation

Correct answer: Decline to provide non-beneficial or harmful treatment while explaining your reasoning and alternatives

Autonomy does not compel a doctor to provide treatment that is harmful or not clinically indicated.

Question 10: A 60-year-old man develops a tender, erythematous wound with purulent discharge on postoperative day 5. Which type of surgical site infection is this?

Superficial incisional SSI (Correct answer)
Sterile inflammatory reaction
Organ/space SSI
Deep incisional SSI

Correct answer: Superficial incisional SSI

A superficial incisional SSI involves only skin and subcutaneous tissue within 30 days of surgery.

Question 11: A 22-year-old presents with painful genital ulcers and bilateral inguinal lymphadenopathy. PCR confirms herpes simplex virus type 2. What is the first-line treatment?

Foscarnet
Ganciclovir
Cidofovir
Valacyclovir (Correct answer)

Correct answer: Valacyclovir

Valacyclovir (or acyclovir) is first-line therapy for primary genital herpes simplex infection.

Question 12: Which bias arises when cases recall past exposures more thoroughly than controls in a case-control study?

Berkson bias
Lead-time bias
Selection bias
Recall bias (Correct answer)

Correct answer: Recall bias

Recall bias occurs because people with disease often remember exposures differently than healthy controls.

Question 13: A 45-year-old immunocompromised patient develops a vesicular rash in a dermatomal distribution with severe pain. Which antiviral should be started within 72 hours?

Lamivudine
Valacyclovir (Correct answer)
Ribavirin
Oseltamivir

Correct answer: Valacyclovir

Valacyclovir started within 72 hours of herpes zoster onset reduces duration and severity, including post-herpetic neuralgia.

Question 14: A junior doctor notices that a senior surgical consultant frequently appears to have tremors and slurred speech during morning rounds, particularly on Mondays. The junior doctor smells alcohol on the consultant's breath on one occasion. When privately asked, the consultant dismisses it as fatigue. According to the Health Practitioner Regulation National Law, what is the junior doctor's primary professional obligation?

Advise the consultant to self-report to the Medical Board of Australia.
Make a mandatory report to the Australian Health Practitioner Regulation Agency (AHPRA) about potential notifiable conduct. (Correct answer)
Directly report the concerns to the hospital's Director of Medical Services.
Discuss the concerns with other junior doctors to see if they have noticed similar behaviour.

Correct answer: Make a mandatory report to the Australian Health Practitioner Regulation Agency (AHPRA) about potential notifiable conduct.

The scenario describes a reasonable belief that a practitioner may be practising while intoxicated, which falls under the definition of 'notifiable conduct' in the National Law. All registered health practitioners have a legal obligation to report notifiable conduct to AHPRA to protect the public from harm. While discussing with a hospital manager (DMS) is a reasonable step, it does not absolve the practitioner of their personal mandatory reporting obligation. Discussing with peers is inappropriate and advising the consultant to self-report does not fulfil the observer's duty.

Question 15: Hemoglobin cannot transport carbon dioxide.

B) True
A) False (Correct answer)

Correct answer: A) False

Hemoglobin can indeed transport carbon dioxide, although it is not its primary function. About 10-20% of CO2 is transported bound to the amino groups of hemoglobin, forming carbaminohemoglobin. The majority of CO2 is transported as bicarbonate ions.

Question 16: A 70-year-old woman has a new headache, scalp tenderness, jaw claudication and a raised ESR. What is the most appropriate immediate management?

Start high-dose corticosteroids immediately (Correct answer)
Prescribe simple analgesia only
Await temporal artery biopsy before treating
Arrange routine outpatient review

Correct answer: Start high-dose corticosteroids immediately

Suspected giant cell arteritis requires immediate corticosteroids to prevent irreversible blindness, without waiting for biopsy.

Question 17: CO2 amount in expired air is _________.

0.04%
21%
0.03%
3.6% (Correct answer)

Correct answer: 3.6%

The amount of carbon dioxide in expired air is significantly higher than in inspired air, reflecting the CO2 produced by cellular metabolism. While inspired air contains about 0.04% CO2, expired air typically contains around 3.6% to 5% CO2.

Question 18: A 35-year-old man has hypertension, episodic headaches, sweating and palpitations with elevated plasma metanephrines. What tumour is responsible?

Prolactinoma
Phaeochromocytoma (Correct answer)
Insulinoma
Aldosteronoma

Correct answer: Phaeochromocytoma

Paroxysmal hypertension with raised metanephrines indicates a catecholamine-secreting phaeochromocytoma.

Question 19: An elderly patient with polymyalgia rheumatica develops a new headache and jaw claudication. What complication must be excluded urgently?

Cluster headache
Giant cell (temporal) arteritis (Correct answer)
Trigeminal neuralgia
Migraine

Correct answer: Giant cell (temporal) arteritis

Headache and jaw claudication signal giant cell arteritis, which can cause irreversible blindness.

Question 20: A patient develops haematemesis with melaena and known cirrhosis. What is the most likely source?

Gastric ulcer
Bleeding oesophageal varices (Correct answer)
Mallory-Weiss tear
Angiodysplasia

Correct answer: Bleeding oesophageal varices

Portal hypertension from cirrhosis causes oesophageal varices, a common cause of major upper GI bleeding.

Question 21: A 28-year-old woman with multiple sclerosis develops acute painful loss of vision in one eye with reduced colour vision. What is the most likely diagnosis?

Optic neuritis (Correct answer)
Acute angle-closure glaucoma
Retinal detachment
Central retinal artery occlusion

Correct answer: Optic neuritis

Painful monocular visual loss with impaired colour vision in a young patient with MS is typical of optic neuritis.

Question 22: A 65-year-old presents with gradual painless vision loss. Fundoscopy shows a cup-to-disc ratio of 0.8 and intraocular pressure is 28 mmHg bilaterally. What is the most likely diagnosis?

Central retinal vein occlusion
Age-related macular degeneration
Primary open-angle glaucoma (Correct answer)
Cataracts

Correct answer: Primary open-angle glaucoma

Primary open-angle glaucoma presents with elevated IOP, increased cup-to-disc ratio, and gradual painless peripheral vision loss due to progressive optic nerve damage.

Question 23: A 75-year-old woman is newly diagnosed with heart failure with a reduced ejection fraction (HFrEF) of 35%. She has a history of hypertension but no prior myocardial infarction. According to the 2018 National Heart Foundation of Australia and Cardiac Society of Australia and New Zealand guidelines, which combination of medications is recommended as first-line therapy to improve survival?

An ACE inhibitor, a beta-blocker, and a mineralocorticoid receptor antagonist (MRA) (Correct answer)
A diuretic, digoxin, and a beta-blocker
An angiotensin receptor blocker (ARB), a calcium channel blocker, and aspirin
A statin, an ACE inhibitor, and a diuretic

Correct answer: An ACE inhibitor, a beta-blocker, and a mineralocorticoid receptor antagonist (MRA)

The 2018 Australian heart failure guidelines recommend a three-pronged approach for all patients with HFrEF to reduce mortality and hospitalisations. This includes an ACE inhibitor (or an ARB if not tolerated), a beta-blocker (specifically, carvedilol, bisoprolol, or metoprolol succinate), and a mineralocorticoid receptor antagonist (spironolactone or eplerenone). Diuretics are used for symptom control (fluid overload) but do not have a proven mortality benefit. Digoxin is a second-line agent for symptom control. Calcium channel blockers (like verapamil and diltiazem) are generally avoided in HFrEF. Statins are indicated for atherosclerotic disease, not primarily for HFrEF itself.

Question 24: A 45-year-old reports heavy menstrual bleeding with a bulky, irregular uterus on examination. What is the most likely diagnosis?

Uterine fibroids (Correct answer)
Ovarian cyst
Ectopic pregnancy
Endometrial carcinoma

Correct answer: Uterine fibroids

A bulky, irregularly enlarged uterus with menorrhagia is most consistent with uterine fibroids.

Question 25: Which situation is a recognised legal exception that may justify breaching patient confidentiality?

A serious and imminent risk of harm to the patient or others, or a legal/statutory requirement (Correct answer)
The patient is famous
A relative is simply curious
Another doctor wants to know out of interest

Correct answer: A serious and imminent risk of harm to the patient or others, or a legal/statutory requirement

Confidentiality may be overridden to prevent serious imminent harm or to comply with legal duties.

Question 26: A 19-year-old student has had six months of excessive worry about many areas of life, restlessness, muscle tension and difficulty concentrating most days. What is the most likely diagnosis?

Adjustment disorder
Panic disorder
Generalised anxiety disorder (Correct answer)
Obsessive-compulsive disorder

Correct answer: Generalised anxiety disorder

Persistent, excessive, hard-to-control worry across multiple domains for at least six months defines generalised anxiety disorder.

Question 27: A 52-year-old smoker presents with a firm, painless 3 cm neck mass that has been present for 8 weeks. Fine needle aspiration cytology reveals squamous cell carcinoma. What is the most important next investigative step?

Empirical radiotherapy to the neck
PET-CT scan only
Panendoscopy to identify the primary tumour (Correct answer)
Immediate radical neck dissection

Correct answer: Panendoscopy to identify the primary tumour

Metastatic SCC in the neck requires panendoscopy (examination of the nasopharynx, oropharynx, hypopharynx, larynx, and oesophagus) with biopsies to identify the primary tumour before definitive treatment planning.

Question 28: A 68-year-old woman undergoes a DEXA scan which reveals a T-score of -2.8 at the femoral neck. She has no personal history of fragility fractures. According to Australian guidelines, which of the following is the most appropriate first-line pharmacological treatment for her postmenopausal osteoporosis?

Teriparatide
Alendronate (Correct answer)
Raloxifene
Denosumab

Correct answer: Alendronate

According to Australian and international guidelines, oral bisphosphonates such as alendronate are the recommended first-line pharmacological treatment for most postmenopausal women with osteoporosis. [35, 43] They are effective in reducing the risk of vertebral and non-vertebral fractures, are widely available, and cost-effective. Denosumab is typically considered a second-line option or for those who cannot tolerate bisphosphonates. Teriparatide is an anabolic agent reserved for severe osteoporosis with multiple fractures. Raloxifene is less effective at preventing non-vertebral fractures and is not typically a first-line choice for this patient profile. [14]

Question 29: A 38-year-old with recurrent sinusitis presents with nasal polyps, bronchial asthma, and develops bronchospasm after taking aspirin for a headache. What is this triad called?

Wegener's granulomatosis
Samter's triad (aspirin-exacerbated respiratory disease) (Correct answer)
Churg-Strauss syndrome
Kartagener syndrome

Correct answer: Samter's triad (aspirin-exacerbated respiratory disease)

Samter's triad (aspirin-exacerbated respiratory disease) consists of asthma, nasal polyps, and aspirin/NSAID sensitivity caused by aberrant arachidonic acid metabolism.

Question 30: A patient with sickle cell disease presents in vasoocclusive crisis with severe pain. Which medication reduces the frequency of crises by increasing foetal haemoglobin (HbF)?

Deferoxamine
Penicillin V
Erythropoietin
Hydroxyurea (Correct answer)

Correct answer: Hydroxyurea

Hydroxyurea increases production of foetal haemoglobin (HbF), which inhibits HbS polymerisation and reduces vasoocclusive crises in sickle cell disease.

Question 31: A 58-year-old man with a long history of GORD undergoes a surveillance endoscopy. Biopsies from a 4 cm segment of columnar-lined oesophagus confirm Barrett's oesophagus with low-grade dysplasia. The finding of low-grade dysplasia is confirmed by a second specialist pathologist. According to Australian guidelines, what is the most appropriate next step in management?

Repeat endoscopy with Seattle protocol biopsies in 6 months. (Correct answer)
Refer for endoscopic radiofrequency ablation.
Repeat endoscopy with biopsies in 2-3 years.
Commence annual endoscopic surveillance.

Correct answer: Repeat endoscopy with Seattle protocol biopsies in 6 months.

According to Australian guidelines for the management of Barrett's oesophagus, if low-grade dysplasia is confirmed by a second pathologist, the recommended action is to repeat the endoscopy in 6 months with meticulous Seattle protocol biopsies (quadrantal biopsies every 1 cm). This is to closely monitor for progression to high-grade dysplasia or adenocarcinoma. Annual surveillance may be considered later if subsequent endoscopies are negative for dysplasia. A 2-3 year interval is appropriate for long-segment Barrett's without dysplasia. Endoscopic ablation is typically reserved for confirmed and persistent high-grade dysplasia or early adenocarcinoma.

Question 32: Spirometry shows FEV1/FVC ratio of 0.62 with reduced FEV1. This pattern is characteristic of which condition?

Obstructive airways disease such as COPD (Correct answer)
Pulmonary fibrosis
Neuromuscular weakness
Chest wall deformity

Correct answer: Obstructive airways disease such as COPD

A reduced FEV1/FVC ratio below 0.7 indicates an obstructive ventilatory defect such as COPD or asthma.

Question 33: A child with pyloric stenosis typically shows which biochemical abnormality?

Respiratory alkalosis
Hyperchloraemic acidosis
Metabolic acidosis with high anion gap
Hypochloraemic hypokalaemic metabolic alkalosis (Correct answer)

Correct answer: Hypochloraemic hypokalaemic metabolic alkalosis

Loss of gastric acid through vomiting produces a hypochloraemic, hypokalaemic metabolic alkalosis.

Question 34: A 33-year-old woman presents with intermittent right upper quadrant pain after fatty meals and a positive Murphy's sign. What is the most appropriate first-line imaging?

MRCP
CT abdomen
Plain abdominal X-ray
Abdominal ultrasound (Correct answer)

Correct answer: Abdominal ultrasound

Ultrasound is the first-line investigation for suspected gallstones and cholecystitis.

Question 35: A 40-year-old woman reports fatigable weakness with drooping eyelids and double vision that worsen through the day. What is the most likely diagnosis?

Motor neurone disease
Myasthenia gravis (Correct answer)
Guillain-Barré syndrome
Multiple sclerosis

Correct answer: Myasthenia gravis

Fatigable ptosis and diplopia that worsen with activity are characteristic of myasthenia gravis.

Question 36: Which immunoglobulin class is primarily responsible for the secondary (anamnestic) immune response?

IgE
IgG (Correct answer)
IgA
IgM

Correct answer: IgG

IgG is the predominant antibody of the secondary immune response, providing long-lasting humoral immunity.

Question 37: A 65-year-old presents with lymphocytosis (lymphocyte count 80 × 10⁹/L), smudge cells on peripheral blood film, and painless generalised lymphadenopathy. What is the most likely diagnosis?

Chronic lymphocytic leukaemia (Correct answer)
Acute lymphoblastic leukaemia
Hairy cell leukaemia
T-cell lymphoma

Correct answer: Chronic lymphocytic leukaemia

Chronic lymphocytic leukaemia (CLL) presents with marked lymphocytosis, smudge cells on blood film, and indolent lymphadenopathy in older adults.

Question 38: A 40-year-old presents with chronic diarrhea, weight loss, and CD4 count of 50 cells/µL. Stool acid-fast staining shows 4–6 µm oocysts. What is the causative organism?

Cyclospora cayetanensis
Giardia lamblia
Cryptosporidium parvum (Correct answer)
Isospora belli

Correct answer: Cryptosporidium parvum

Cryptosporidium parvum causes severe, profuse watery diarrhea in HIV patients with CD4 <100; oocysts are 4–6 µm and acid-fast positive.

Question 39: A type 1 diabetic presents drowsy with a blood glucose of 28 mmol/L, ketonaemia and a pH of 7.18. What is the most important first step in management?

Intravenous bicarbonate
Intravenous isotonic fluid resuscitation (Correct answer)
Oral rehydration
Subcutaneous long-acting insulin

Correct answer: Intravenous isotonic fluid resuscitation

Fluid resuscitation is the priority in diabetic ketoacidosis before and alongside an insulin infusion.

Question 40: A woman at 38 weeks has spontaneous rupture of membranes with green-stained liquor. What does this indicate?

Maternal infection only
Normal amniotic fluid
Oligohydramnios
Meconium-stained liquor requiring closer fetal monitoring (Correct answer)

Correct answer: Meconium-stained liquor requiring closer fetal monitoring

Green liquor indicates meconium passage, which may signal fetal compromise and warrants continuous monitoring.

Question 41: A child presents limping with hip pain and a recent viral illness, but is afebrile and well. What is the most likely diagnosis?

Slipped capital femoral epiphysis
Perthes disease
Septic arthritis
Transient synovitis (Correct answer)

Correct answer: Transient synovitis

Transient synovitis follows a viral illness, presenting with a limp in a well, afebrile child.

Question 42: A patient develops oliguria with urine output under 0.5 mL/kg/hr postoperatively. What is the first step?

Assess volume status and give a fluid challenge if hypovolaemic (Correct answer)
Start dialysis immediately
Restrict all fluids
Give a loop diuretic first-line

Correct answer: Assess volume status and give a fluid challenge if hypovolaemic

Postoperative oliguria is most often pre-renal, so volume assessment and a fluid challenge come first.

Question 43: A patient's adult child demands information about the patient's diagnosis. The competent patient has not consented. What should you do?

Share only the diagnosis but not the prognosis
Share freely with close family
Demand the child prove their identity then share
Maintain confidentiality unless the patient consents or a legal exception applies (Correct answer)

Correct answer: Maintain confidentiality unless the patient consents or a legal exception applies

Patient confidentiality must be maintained without consent, even with close relatives.

Question 44: The humburger shift is also known as ___________

Bicarbonate shift
Chloride shift (Correct answer)
Potassium shift
Sodium shift

Correct answer: Chloride shift

The Hamburger shift is also known as the chloride shift. This process occurs in red blood cells, where bicarbonate ions (HCO3-), formed from CO2, are exchanged for chloride ions (Cl-) across the cell membrane. This mechanism facilitates the transport of CO2 from tissues to the lungs while maintaining electrical neutrality within the red blood cell.

Question 45: A 30-year-old of Mediterranean descent has a haemoglobin of 85 g/L, MCV of 62 fL, normal iron studies, and elevated HbA2 on electrophoresis. What is the most likely diagnosis?

Beta-thalassaemia trait (Correct answer)
Iron deficiency anaemia
Anaemia of chronic disease
Lead poisoning

Correct answer: Beta-thalassaemia trait

Beta-thalassaemia trait presents with mild microcytic anaemia, normal or elevated HbA2 (>3.5%) on haemoglobin electrophoresis, and normal iron studies.

Question 46: Which prevention strategy targets the whole population rather than high-risk individuals?

High-risk strategy
Screening of contacts
Population (mass) strategy (Correct answer)
Tertiary rehabilitation

Correct answer: Population (mass) strategy

A population strategy aims to shift the entire risk distribution, as described by Geoffrey Rose.

Question 47: A 55-year-old patient develops disseminated intravascular coagulation (DIC). Laboratory findings include prolonged PT/APTT, low fibrinogen, elevated D-dimer, and thrombocytopenia. What is the primary treatment approach?

Administer heparin to prevent further clotting
Give fresh frozen plasma alone
Administer platelet transfusion alone
Treat the underlying cause (Correct answer)

Correct answer: Treat the underlying cause

The cornerstone of DIC management is treating the underlying trigger (e.g., sepsis, malignancy), as supportive blood products alone without addressing the cause will not resolve DIC.

Question 48: An elderly man develops fluctuating cognition, recurrent visual hallucinations and spontaneous parkinsonism. What is the most likely diagnosis?

Vascular dementia
Alzheimer's disease
Normal pressure hydrocephalus
Lewy body dementia (Correct answer)

Correct answer: Lewy body dementia

Fluctuating cognition, vivid visual hallucinations and parkinsonism are the core features of Lewy body dementia.

Question 49: A patient with ulcerative colitis develops abdominal distension, fever, and a colon diameter over 6 cm. What is this complication?

Pseudo-obstruction
Toxic megacolon (Correct answer)
Intussusception
Sigmoid volvulus

Correct answer: Toxic megacolon

Toxic megacolon is a life-threatening colonic dilatation complicating severe colitis.

Question 50: A 32-year-old has a positive 75g OGTT at 26 weeks. What is the most appropriate initial management?

Immediate insulin therapy
No intervention until symptoms appear
Metformin and induction at 34 weeks
Dietary modification and blood glucose monitoring (Correct answer)

Correct answer: Dietary modification and blood glucose monitoring

First-line management of gestational diabetes is dietary modification with self-monitoring of blood glucose before pharmacotherapy.

Question 51: A patient has epigastric pain relieved by eating and worse at night. Which ulcer is most likely?

Oesophageal ulcer
Gastric ulcer
Stress ulcer
Duodenal ulcer (Correct answer)

Correct answer: Duodenal ulcer

Duodenal ulcer pain classically improves with food and recurs hours later or at night.

Question 52: A 45-year-old woman has a microcytic, hypochromic anaemia with serum ferritin of 5 µg/L and low serum iron. What is the most likely cause?

Thalassaemia trait
Anaemia of chronic disease
Sideroblastic anaemia
Iron deficiency anaemia (Correct answer)

Correct answer: Iron deficiency anaemia

Low ferritin combined with microcytic hypochromic anaemia and low serum iron is diagnostic of iron deficiency anaemia.

Question 53: A rhesus-negative mother delivers a rhesus-positive baby. What is required to prevent sensitisation?

Exchange transfusion of the baby
Maternal blood transfusion
Anti-D immunoglobulin within 72 hours (Correct answer)
No treatment is necessary

Correct answer: Anti-D immunoglobulin within 72 hours

Anti-D immunoglobulin given within 72 hours prevents maternal alloimmunisation against fetal RhD antigens.

Question 54: Which finding is most characteristic of severe pre-eclampsia rather than gestational hypertension?

BP 130/85 mmHg at term
Proteinuria with epigastric pain and visual disturbance (Correct answer)
Isolated lower limb oedema
BP 140/90 mmHg with no proteinuria

Correct answer: Proteinuria with epigastric pain and visual disturbance

End-organ involvement such as epigastric pain and visual disturbance with proteinuria signifies severe pre-eclampsia.

Question 55: A child presents with a 'slapped cheek' facial rash followed by a lacy reticular rash on the limbs. What is the causative organism?

Measles virus
Group A streptococcus
Parvovirus B19 (Correct answer)
Varicella zoster virus

Correct answer: Parvovirus B19

Erythema infectiosum (fifth disease) causing slapped-cheek appearance is due to parvovirus B19.

Question 56: Which ECG feature is diagnostic of complete (third-degree) heart block?

Delta wave
Progressive PR prolongation then a dropped beat
Fixed prolonged PR interval
AV dissociation with independent atrial and ventricular rates (Correct answer)

Correct answer: AV dissociation with independent atrial and ventricular rates

Complete heart block shows atria and ventricles beating independently with no relationship between P waves and QRS complexes.

Question 57: A 78-year-old woman with oesophageal cancer is found to be severely malnourished, having lost 15% of her body weight over 3 months. Pre-operative nutritional support is initiated via a nasogastric tube. The initiation of feeding in this patient must be done cautiously to avoid which of the following life-threatening metabolic complications?

Metabolic acidosis
Refeeding syndrome (Correct answer)
Hypernatraemia
Hypercalcaemia

Correct answer: Refeeding syndrome

This patient is at high risk for refeeding syndrome due to severe malnutrition. This syndrome is a potentially fatal condition caused by rapid shifts in fluids and electrolytes that occur when nutritional support is initiated in a chronically starved patient. The shift from fat to carbohydrate metabolism stimulates insulin release, which drives phosphate, potassium, and magnesium into cells, leading to profound hypophosphataemia, hypokalaemia, and hypomagnesaemia. These electrolyte shifts can cause cardiac, pulmonary, and neurological failure.

Question 58: A new screening test has high sensitivity but low specificity. What is the most likely consequence in a low-prevalence population?

Many false negatives
Many false positives (Correct answer)
High positive predictive value
Low test recall

Correct answer: Many false positives

Low specificity combined with low disease prevalence generates a large number of false-positive results.

Question 59: A 35-year-old HIV-positive patient with CD4 count of 80 cells/µL presents with headache, fever, and meningismus. India ink stain of CSF shows encapsulated yeast. What is the most appropriate treatment?

Fluconazole alone
Voriconazole
Caspofungin
Amphotericin B plus flucytosine (Correct answer)

Correct answer: Amphotericin B plus flucytosine

Cryptococcal meningitis in immunocompromised patients is treated with induction therapy using amphotericin B plus flucytosine.

Question 60: A patient with idiopathic pulmonary fibrosis is most likely to have which examination finding?

Bronchial breathing at the apex
Fine bibasal end-inspiratory crackles and clubbing (Correct answer)
Expiratory wheeze
Coarse early inspiratory crackles

Correct answer: Fine bibasal end-inspiratory crackles and clubbing

Fine bibasal end-inspiratory crackles with finger clubbing are characteristic of pulmonary fibrosis.

Question 61: A mother brings her 18-month-old son for a developmental check. She is concerned about his progress. Which of the following findings would be considered a 'red flag' for developmental delay at this age, warranting further investigation?

He is not yet able to run.
He is not yet walking independently.
He cannot build a tower of more than 4 blocks.
He does not use any single, meaningful words. (Correct answer)

Correct answer: He does not use any single, meaningful words.

While there is a range for achieving milestones, the absence of any single, meaningful words by 18 months is a significant language delay and a developmental red flag. Most children are walking by 15-16 months, but not walking at 18 months, while requiring assessment, is less concerning than a complete lack of single words, especially if other motor skills are present. Running and building a tower of more than 4 blocks are milestones typically expected closer to 24 months.

Question 62: A migrant patient presents with chronic cough, night sweats, weight loss and an upper lobe cavitating lesion. What is the most appropriate initial investigation?

Spirometry
Echocardiography
D-dimer
Sputum for acid-fast bacilli and culture (Correct answer)

Correct answer: Sputum for acid-fast bacilli and culture

The presentation suggests pulmonary tuberculosis, best confirmed with sputum smear and culture for acid-fast bacilli.

Question 63: Which test is most sensitive for the diagnosis of active tuberculosis in a sputum sample?

Tuberculin skin test (Mantoux)
Mycobacterial culture (Correct answer)
Ziehl-Neelsen stain
Interferon-gamma release assay (IGRA)

Correct answer: Mycobacterial culture

Mycobacterial culture (Lowenstein-Jensen or liquid MGIT) remains the gold standard for diagnosing active TB due to its highest sensitivity.

Question 64: Which investigation is the gold standard to diagnose malrotation?

Upper GI contrast study (Correct answer)
Abdominal ultrasound
CT abdomen
Plain abdominal X-ray

Correct answer: Upper GI contrast study

An upper GI contrast study showing an abnormally placed duodenojejunal junction is the diagnostic standard for malrotation.

Question 65: A p-value of 0.04 in a study comparing two treatments means there is approximately a 4% probability that:

The result is clinically important
The treatment is ineffective
The observed result occurred if the null hypothesis were true (Correct answer)
The study had adequate power

Correct answer: The observed result occurred if the null hypothesis were true

The p-value is the probability of obtaining the observed data or more extreme assuming the null hypothesis is true.

Question 66: A patient undergoes a bone marrow biopsy showing hypercellular marrow with >20% blasts. Flow cytometry reveals CD13, CD33, and MPO positivity. What is the diagnosis?

Acute myeloid leukaemia (AML) (Correct answer)
Acute lymphoblastic leukaemia (ALL)
Chronic myeloid leukaemia (CML)
Myelodysplastic syndrome

Correct answer: Acute myeloid leukaemia (AML)

AML is characterised by ≥20% myeloid blasts in the bone marrow with expression of myeloid markers (CD13, CD33) and myeloperoxidase (MPO).

Question 67: Which medication provides symptomatic relief of acute angina by venodilation and reducing preload?

Oral aspirin
Ramipril
Sublingual glyceryl trinitrate (Correct answer)
Atorvastatin

Correct answer: Sublingual glyceryl trinitrate

Sublingual GTN rapidly relieves angina by reducing preload through venodilation.

Question 68: A 30-year-old African-Caribbean woman has bilateral hilar lymphadenopathy, erythema nodosum and arthralgia. What is the most likely diagnosis?

Lymphoma
Sarcoidosis (Correct answer)
Bronchiectasis
Tuberculosis

Correct answer: Sarcoidosis

Bilateral hilar lymphadenopathy with erythema nodosum and arthralgia (Löfgren syndrome) is characteristic of sarcoidosis.

Question 69: Which is the most common type of gallstone in Western populations?

Pigment stones
Struvite stones
Cholesterol stones (Correct answer)
Calcium carbonate stones

Correct answer: Cholesterol stones

Cholesterol stones are the most common gallstone type in Western countries.

Question 70: What is the recommended management of a confirmed term breech presentation in an otherwise uncomplicated pregnancy?

Routine forceps delivery
Await spontaneous version at term
Immediate caesarean at diagnosis
Offer external cephalic version at 36-37 weeks (Correct answer)

Correct answer: Offer external cephalic version at 36-37 weeks

External cephalic version is offered from around 36-37 weeks to attempt to turn the fetus to cephalic.

Question 71: What is the recommended first-line management of a small, stable, postoperative seroma?

Observation as most resolve spontaneously (Correct answer)
Immediate surgical exploration
Pressurised irrigation
High-dose IV antibiotics

Correct answer: Observation as most resolve spontaneously

Most small seromas reabsorb spontaneously and need only observation.

Question 72: A child has a high fever for 3-4 days that resolves, followed by the appearance of a rose-pink rash on the trunk. What is the most likely diagnosis?

Measles
Rubella
Roseola infantum (HHV-6) (Correct answer)
Scarlet fever

Correct answer: Roseola infantum (HHV-6)

High fever that resolves just as a rose-pink trunk rash appears is classic for roseola caused by HHV-6.

Question 73: A 16-year-old requests contraception and refuses to involve her parents. Under Australian law, what principle determines whether you can prescribe?

You must refuse until she turns 18
Court approval is required for all minors
Gillick competence / mature minor assessment of her understanding (Correct answer)
Parental consent is always mandatory under 18

Correct answer: Gillick competence / mature minor assessment of her understanding

A mature minor who demonstrates sufficient understanding (Gillick competence) may consent to treatment without parental involvement.

Question 74: A 70-year-old woman presents with bilateral shoulder and hip girdle pain and stiffness, with a markedly raised ESR. What is the most likely diagnosis?

Fibromyalgia
Osteoarthritis
Polymyositis
Polymyalgia rheumatica (Correct answer)

Correct answer: Polymyalgia rheumatica

Proximal girdle stiffness with high ESR in an elderly patient suggests polymyalgia rheumatica.

Question 75: The maximum expiration of the lungs after deep inspiration is referred to as ________

Total lung capacity
Inspiratory capacity
Vital capacity (Correct answer)
Functional residual capacity

Correct answer: Vital capacity

Vital capacity is defined as the maximum amount of air a person can exhale from the lungs after a maximum inhalation. It represents the total volume of air that can be moved in and out of the lungs with a forceful breath, indicating overall lung function.

Question 76: Which nerve is most commonly injured in a mid-shaft humeral fracture?

Median nerve
Ulnar nerve
Axillary nerve
Radial nerve (Correct answer)

Correct answer: Radial nerve

The radial nerve runs in the spiral groove and is at risk in mid-shaft humeral fractures, causing wrist drop.

Question 77: A 60-year-old woman presents with a unilateral, painless breast lump that is hard, irregular, and tethered to the skin. What is the most appropriate next investigation?

Triple assessment (clinical, imaging, biopsy) (Correct answer)
Reassurance and review in 6 months
Hormone level testing
Course of antibiotics

Correct answer: Triple assessment (clinical, imaging, biopsy)

Any suspicious breast lump should undergo triple assessment combining examination, imaging, and biopsy.

Question 78: A 38-year-old man presents after a seizure. He has been drinking alcohol heavily for years and stopped two days ago. What is the most likely cause of the seizure?

Hypoglycaemia
Brain tumour
Epilepsy
Alcohol withdrawal (Correct answer)

Correct answer: Alcohol withdrawal

Seizures occurring within 6-48 hours of alcohol cessation are typically due to alcohol withdrawal.

Question 79: Bronchioles are the finest branches of the bronchial intercom.

A) False (Correct answer)
B) True

Correct answer: A) False

Bronchioles are indeed fine branches of the bronchial tree, but they are not the finest. The bronchioles further divide into terminal bronchioles, which then lead to respiratory bronchioles, alveolar ducts, and finally the alveolar sacs, where gas exchange occurs. The alveoli are the ultimate fine structures of the respiratory system.

Question 80: A 3-year-old child presents with a purpuric, non-blanching rash, fever of 39.5°C, and neck stiffness. She appears unwell and drowsy. What is the most critical immediate action?

IV benzylpenicillin (Correct answer)
Blood cultures then await results
Lumbar puncture
CT head before any treatment

Correct answer: IV benzylpenicillin

This presentation is highly suspicious for meningococcal meningitis/septicaemia. IV benzylpenicillin must be given immediately without waiting for investigations as delay increases mortality. Lumbar puncture and CT may follow after stabilisation and treatment have been initiated, and blood cultures should be taken but must not delay antibiotics.

Question 81: Which tumour marker is most useful for monitoring treatment response in colorectal cancer?

PSA
CEA (carcinoembryonic antigen) (Correct answer)
AFP
CA 125

Correct answer: CEA (carcinoembryonic antigen)

CEA is the primary tumour marker for monitoring recurrence and treatment response in colorectal cancer.

Question 82: A 35-year-old man believes he is being followed by government agents, hears voices commenting on his actions, and has shown social withdrawal for the past eight months. What is the most likely diagnosis?

Bipolar affective disorder
Schizoaffective disorder
Schizophrenia (Correct answer)
Delusional disorder

Correct answer: Schizophrenia

Persistent delusions, third-person auditory hallucinations and functional decline beyond a month indicate schizophrenia.

Question 83: A woman at 30 weeks reports reduced fetal movements. What is the appropriate first-line assessment?

Immediate caesarean section
Cardiotocography and ultrasound assessment (Correct answer)
Induction of labour
Reassure without testing

Correct answer: Cardiotocography and ultrasound assessment

Reduced fetal movements warrant CTG and ultrasound to assess fetal wellbeing.

Question 84: In respiratory metabolism, RQ equals 0.6, which means _________

Reaction is anaerobic
Oxidation of respiratory substrate consumed more O2than CO2produced (Correct answer)
Carbohydrate is used as a respiratory substrate
Organic acids are used as a respiratory substrate

Correct answer: Oxidation of respiratory substrate consumed more O2than CO2produced

An RQ of 0.6, which is less than 1, indicates that the respiratory substrate being oxidized requires more oxygen for its complete breakdown than the amount of carbon dioxide it produces. This is characteristic of substrates like fats or certain organic acids, which have a lower oxygen content relative to their carbon and hydrogen.

Question 85: Which class of drug is first-line for symptomatic relief of pulmonary congestion in acute heart failure?

Statin
Calcium channel blocker
Oral beta-blocker
Intravenous loop diuretic (Correct answer)

Correct answer: Intravenous loop diuretic

IV loop diuretics such as frusemide relieve pulmonary congestion in acute decompensated heart failure.

Question 86: A 55-year-old man presents with urinary hesitancy, a PSA of 18 ng/mL, and a hard irregular prostate on digital rectal exam. Biopsy shows adenocarcinoma, Gleason score 7. What is the initial management for localised disease?

Watchful waiting only
Radical prostatectomy or external beam radiotherapy (Correct answer)
Immediate androgen deprivation therapy (ADT)
Chemotherapy with docetaxel

Correct answer: Radical prostatectomy or external beam radiotherapy

Intermediate-risk localised prostate cancer (Gleason 7, elevated PSA) is treated with curative intent via radical prostatectomy or external beam radiotherapy.

Question 87: A patient on long-term corticosteroids is at greatest risk of which musculoskeletal complication?

Osteoporosis (Correct answer)
Septic arthritis
Gout
Rheumatoid arthritis

Correct answer: Osteoporosis

Chronic corticosteroid use accelerates bone loss, increasing osteoporosis and fracture risk.

Question 88: An elderly man presents after a fall with a shortened, externally rotated leg and hip pain. What is the most likely injury?

Knee dislocation
Posterior hip dislocation
Fractured neck of femur (Correct answer)
Pubic ramus fracture

Correct answer: Fractured neck of femur

A shortened, externally rotated leg after a fall is classic for a fractured neck of femur.

Question 89: A patient with gallstones develops fever, jaundice, and right upper quadrant pain (Charcot's triad). What is the diagnosis?

Pancreatitis
Acute cholecystitis
Hepatic abscess
Ascending cholangitis (Correct answer)

Correct answer: Ascending cholangitis

Charcot's triad of fever, jaundice, and RUQ pain indicates ascending cholangitis from biliary obstruction and infection.

Question 90: A doctor posts a deidentified but recognisable patient case on social media. Why is this an ethical problem?

Social media is always prohibited for doctors
Patients may still be identifiable, breaching confidentiality and consent requirements (Correct answer)
It is good public education
It only matters if the patient complains

Correct answer: Patients may still be identifiable, breaching confidentiality and consent requirements

Even 'deidentified' posts can identify patients, so sharing without consent risks a confidentiality breach.

Question 91: A 24-year-old woman presents with a history of irregular menstrual cycles, occurring every 3 to 6 months, and significant acne. An ultrasound report notes that both ovaries have multiple small follicles. According to the Rotterdam criteria, which are widely used in Australia, what additional feature is required to diagnose Polycystic Ovary Syndrome (PCOS)?

Insulin resistance on a glucose tolerance test
A luteinising hormone (LH) to follicle-stimulating hormone (FSH) ratio greater than 2:1
Body Mass Index (BMI) greater than 30 kg/m²
Evidence of clinical or biochemical hyperandrogenism (Correct answer)

Correct answer: Evidence of clinical or biochemical hyperandrogenism

The Rotterdam criteria, which are standard for diagnosing PCOS in Australia, require the presence of two out of three of the following: 1) oligo- or anovulation (manifesting as irregular cycles), 2) clinical or biochemical signs of hyperandrogenism (e.g., hirsutism, severe acne, or elevated testosterone), and 3) polycystic ovaries on ultrasound. This patient already has oligo-ovulation (irregular cycles) and polycystic ovaries on ultrasound. Therefore, the third criterion, evidence of hyperandrogenism (in this case, her significant acne serves as a clinical sign), completes the diagnosis. While insulin resistance, an altered LH:FSH ratio, and obesity are common in PCOS, they are not part of the core diagnostic criteria.

Question 92: According to the Australian National Immunisation Program (NIP) Schedule, at what age is the first dose of the Measles, Mumps, and Rubella (MMR) vaccine routinely given?

4 years
18 months
6 months
12 months (Correct answer)

Correct answer: 12 months

The Australian National Immunisation Program (NIP) Schedule recommends the first dose of the MMR vaccine be administered at 12 months of age. A second dose, usually as part of the MMRV (Measles, Mumps, Rubella, Varicella) vaccine, is given at 18 months. The 4-year-old vaccination includes a booster for DTPa-IPV.

Question 93: A child with a sandpaper-like rash, strawberry tongue, fever and a recent streptococcal pharyngitis most likely has which condition?

Roseola
Measles
Kawasaki disease
Scarlet fever (Correct answer)

Correct answer: Scarlet fever

A sandpaper rash with strawberry tongue following streptococcal throat infection is scarlet fever.

Question 94: A patient with X-linked agammaglobulinemia (Bruton's disease) would be most susceptible to which type of infection?

Encapsulated bacterial infections (Correct answer)
Parasitic infections
Intracellular viral infections
Fungal infections

Correct answer: Encapsulated bacterial infections

Bruton's agammaglobulinemia causes absence of B cells and immunoglobulins, impairing opsonization of encapsulated bacteria such as Streptococcus pneumoniae and Haemophilus influenzae.

Question 95: Which type of epidemic curve suggests a common point-source exposure?

A single sharp peak (Correct answer)
A bimodal seasonal pattern
A series of progressively rising peaks
A flat continuous plateau

Correct answer: A single sharp peak

A point-source outbreak typically produces a single sharp peak within one incubation period.

Question 96: A vaccine trial reports a relative risk reduction of 80%. If the unvaccinated risk is 10%, what is the absolute risk reduction?

8 percentage points (Correct answer)
20 percentage points
80 percentage points
2 percentage points

Correct answer: 8 percentage points

Absolute risk reduction equals relative risk reduction times baseline risk, so 0.80 × 10% = 8%.

Question 97: A 16-year-old has recurrent intrusive thoughts of contamination and spends hours washing his hands, recognising the behaviour as excessive. What is the most likely diagnosis?

Schizophrenia
Specific phobia
Generalised anxiety disorder
Obsessive-compulsive disorder (Correct answer)

Correct answer: Obsessive-compulsive disorder

Intrusive obsessions and time-consuming compulsions that the person recognises as excessive define OCD.

Question 98: A 60-year-old renal transplant recipient presents with fever and a rising serum creatinine 3 months post-transplant. CMV antigenemia assay is positive. What is the treatment of choice?

Foscarnet
Cidofovir
Acyclovir
Ganciclovir (IV) or valganciclovir (oral) (Correct answer)

Correct answer: Ganciclovir (IV) or valganciclovir (oral)

Ganciclovir IV or oral valganciclovir is the first-line treatment for CMV disease in transplant recipients.

Question 99: A 6-year-old has brief episodes of staring and eyelid fluttering, several times a day, each lasting a few seconds with immediate recovery. What is the most likely diagnosis?

Complex partial seizures
Daydreaming
Tic disorder
Absence (petit mal) seizures (Correct answer)

Correct answer: Absence (petit mal) seizures

Brief frequent staring spells with abrupt onset and recovery in a child are typical absence seizures.

Question 100: What is the most appropriate initial fluid for resuscitating a hypovolaemic surgical patient?

Packed red cells immediately in all cases
Hypertonic saline 3%
Balanced crystalloid such as Hartmann's solution (Correct answer)
5% dextrose

Correct answer: Balanced crystalloid such as Hartmann's solution

Balanced crystalloids are first-line for restoring intravascular volume in hypovolaemia.

Question 101: Hypercalcaemia due to PTHrP secretion is most classically associated with which lung cancer type?

Large cell carcinoma
Squamous cell carcinoma (Correct answer)
Small cell carcinoma
Adenocarcinoma

Correct answer: Squamous cell carcinoma

Squamous cell lung carcinoma is the type most associated with PTHrP-mediated hypercalcaemia.

Question 102: A child presents with palpable purpura over the buttocks and lower limbs, joint pain, abdominal pain and haematuria. What is the most likely diagnosis?

Idiopathic thrombocytopenic purpura
Meningococcaemia
Haemolytic uraemic syndrome
Henoch-Schönlein purpura (IgA vasculitis) (Correct answer)

Correct answer: Henoch-Schönlein purpura (IgA vasculitis)

Palpable purpura on the legs/buttocks with arthralgia, abdominal pain and renal involvement defines HSP.

Question 103: A 62-year-old man is scheduled for an elective inguinal hernia repair. He has no known drug allergies. According to Australian Therapeutic Guidelines for surgical prophylaxis, what is the optimal timing for the administration of intravenous antibiotics to prevent a surgical site infection?

In the post-anaesthesia care unit (PACU)
Two hours prior to skin incision
Within 60 minutes prior to skin incision (Correct answer)
At the time of skin closure

Correct answer: Within 60 minutes prior to skin incision

To be effective in preventing surgical site infections (SSIs), prophylactic antibiotics must be present in the tissues at a bactericidal concentration at the time of the initial incision. The standard recommendation is to administer the intravenous antibiotic dose within the 60 minutes preceding the skin incision. This ensures peak tissue levels are achieved when the wound is created and the risk of bacterial contamination begins. Administering it too early (>120 minutes) may lead to sub-therapeutic levels, while administration after the incision is made is not considered prophylactic.

Question 104: A healthcare worker is exposed to a needlestick from an HBeAg-positive patient. The worker is unvaccinated. What is the most appropriate immediate management?

Hepatitis B immune globulin (HBIG) plus hepatitis B vaccination (Correct answer)
Hepatitis B vaccination alone
Tenofovir prophylaxis
No intervention needed

Correct answer: Hepatitis B immune globulin (HBIG) plus hepatitis B vaccination

Post-exposure prophylaxis for hepatitis B in unvaccinated individuals requires both HBIG (immediate passive immunity) and hepatitis B vaccine.

Question 105: A child with drooling, high fever, muffled voice and a tripod posture who avoids lying flat most likely has which condition?

Epiglottitis (Correct answer)
Bronchiolitis
Asthma
Croup

Correct answer: Epiglottitis

Toxic appearance, drooling, muffled voice and tripod positioning suggest acute epiglottitis.

Question 106: A 68-year-old presents with splenomegaly, elevated RBC count, haematocrit of 58%, and JAK2 V617F mutation. What is the diagnosis?

Secondary polycythaemia
Polycythaemia vera (Correct answer)
Myelofibrosis
Essential thrombocythaemia

Correct answer: Polycythaemia vera

Polycythaemia vera is a myeloproliferative neoplasm characterised by elevated RBC mass, splenomegaly, and JAK2 V617F mutation in >95% of cases.

Question 107: A 15-year-old girl attends a GP appointment alone and requests contraception. She is assessed to be a 'Gillick-competent' minor, meaning she has sufficient understanding and intelligence to comprehend the nature and implications of the proposed treatment. Her parents are unaware of the appointment. Which of the following is the most ethically and legally sound action for the GP?

Prescribe the contraception as the patient's confidentiality takes precedence. (Correct answer)
Contact the parents to inform them of their daughter's request.
Refuse to prescribe until parental consent is obtained.
Agree to prescribe only if the patient agrees to inform her parents within one month.

Correct answer: Prescribe the contraception as the patient's confidentiality takes precedence.

In Australia, the principle of 'Gillick competence' (derived from UK common law and accepted in Australia) allows a minor who has sufficient maturity and intelligence to understand the proposed treatment to consent to it without parental knowledge or consent. In this situation, the duty of confidentiality owed to the competent minor patient is paramount. Prescribing contraception is appropriate. Breaching the patient's confidentiality by contacting the parents would be inappropriate and illegal, and making treatment conditional on her telling her parents undermines her autonomy and right to confidential medical care.

Question 108: Which liver function pattern best indicates obstructive (cholestatic) jaundice?

Very high AST and ALT with normal ALP
Isolated raised bilirubin only
Low albumin alone
Markedly raised ALP and GGT with milder transaminase rise (Correct answer)

Correct answer: Markedly raised ALP and GGT with milder transaminase rise

Cholestasis produces disproportionately elevated ALP and GGT relative to transaminases.

Question 109: A meta-analysis shows high heterogeneity (I² = 85%). This indicates that:

All studies agree closely
The pooled estimate is highly precise
Publication bias is absent
Study results vary substantially beyond chance (Correct answer)

Correct answer: Study results vary substantially beyond chance

A high I² value reflects large variability between study results not explained by chance alone.

Question 110: A 25-year-old childcare worker is diagnosed with scabies after presenting with an intensely pruritic rash that is worse at night, affecting her finger web spaces and wrists. What is the most crucial component of her management plan to prevent re-infestation and spread?

Prescribing a course of oral antibiotics to prevent secondary infection
Washing all bed linen and clothing in cold water with standard detergent
Applying topical permethrin cream only to the visibly affected areas of skin
Simultaneously treating all household members and close contacts, regardless of symptoms (Correct answer)

Correct answer: Simultaneously treating all household members and close contacts, regardless of symptoms

Effective management of scabies requires the simultaneous treatment of the infected individual and all of their close household and sexual contacts, even if they are asymptomatic. [7, 12, 30] This is because contacts can be infested but remain in the asymptomatic incubation period (which can be several weeks), acting as a reservoir for re-infestation. Topical treatment must be applied to the entire body, not just affected areas. Linen should be washed in hot water. Antibiotics are only used for secondary bacterial infections, not the primary infestation.

Question 111: A research participant wants to withdraw from a clinical trial midway. What is the correct response?

Allow withdrawal at any time without penalty or impact on their care (Correct answer)
Refuse, as they committed to the trial
Allow withdrawal only with investigator approval
Charge them for costs incurred

Correct answer: Allow withdrawal at any time without penalty or impact on their care

Participants may withdraw from research at any time without penalty or effect on their ongoing care.

Question 112: Which classification grades surgical complications by the therapy required to treat them?

Clavien-Dindo classification (Correct answer)
Glasgow score
ASA classification
TNM classification

Correct answer: Clavien-Dindo classification

The Clavien-Dindo system grades postoperative complications according to the intervention needed.

Question 113: A 68-year-old man is brought to the emergency department with a sudden onset of left-sided facial droop, arm weakness, and slurred speech. The symptoms started 90 minutes ago. He has a history of hypertension. His blood pressure is 170/95 mmHg and his blood glucose is 7.2 mmol/L. According to Australian stroke guidelines, what is the most crucial next step in management?

Commence an intravenous infusion of labetalol to lower his blood pressure.
Perform an urgent non-contrast CT scan of the brain. (Correct answer)
Administer 300mg of aspirin immediately.
Arrange for an urgent MRI of the brain with diffusion-weighted imaging.

Correct answer: Perform an urgent non-contrast CT scan of the brain.

The most critical initial step in managing a patient with suspected acute ischaemic stroke is to perform an urgent non-contrast CT scan of the brain. This is essential to exclude intracranial haemorrhage, which is a contraindication to thrombolytic therapy. Thrombolysis is a time-critical intervention, and imaging should not be delayed. While aspirin is indicated, it is only given after a haemorrhagic stroke has been excluded. An MRI provides more detail but is less readily available and takes longer, potentially delaying treatment. Blood pressure management is important but is secondary to the initial diagnostic imaging.

Question 114: What is the first-line investigation for suspected polycystic ovary syndrome alongside clinical features?

CT abdomen
Pelvic ultrasound and hormonal profile (Correct answer)
Laparoscopy
Endometrial biopsy

Correct answer: Pelvic ultrasound and hormonal profile

PCOS diagnosis uses the Rotterdam criteria, supported by pelvic ultrasound and hormonal testing.

Question 115: According to the Wilson and Jungner criteria, which of the following is an essential principle for a successful and ethical population-based screening program?

The screening test must have 100% sensitivity.
The natural history of the condition does not need to be well understood.
The condition must have a very high prevalence in the population.
There should be an accepted and available treatment for the condition if detected. (Correct answer)

Correct answer: There should be an accepted and available treatment for the condition if detected.

A core principle of screening is that there must be an effective and accessible treatment for individuals diagnosed with the condition. Screening for a disease for which no effective treatment exists would provide little benefit to the individual or the population and could cause unnecessary anxiety and harm.

Question 116: A 70-year-old man presents with an irregularly irregular pulse and palpitations. ECG shows absent P waves and irregular R-R intervals. What is the diagnosis?

Atrial fibrillation (Correct answer)
First-degree heart block
Atrial flutter
Ventricular tachycardia

Correct answer: Atrial fibrillation

Absent P waves with irregularly irregular rhythm is characteristic of atrial fibrillation.

Question 117: A 35-year-old intravenous drug user presents to the emergency department with a 2-day history of a severely painful, swollen, and warm right knee, accompanied by a fever of 38.8°C. He is unable to bear weight on the leg. Which of the following investigations is the most critical for establishing a definitive diagnosis of septic arthritis?

Plain radiograph of the knee
Synovial fluid analysis and culture (Correct answer)
Blood cultures
Serum C-reactive protein (CRP) and Erythrocyte Sedimentation Rate (ESR)

Correct answer: Synovial fluid analysis and culture

The gold standard and most critical investigation for diagnosing septic arthritis is arthrocentesis followed by synovial fluid analysis (for cell count, Gram stain, and crystals) and culture. [2, 5, 10] This directly identifies the presence and type of infection within the joint space. While serum inflammatory markers (CRP, ESR) are usually elevated, they are non-specific. [13] Blood cultures are important as they may be positive but can be negative even with joint infection. Plain radiographs are often normal in the early stages of septic arthritis.

Question 118: A patient sustained a suspicious injury and you suspect domestic violence. The competent adult patient asks you not to report it. What is the general approach?

Respect the competent adult's wishes while offering support and information, unless a mandatory reporting law applies (Correct answer)
Tell their partner directly
Refuse to treat until they report it
Report immediately against their wishes in all cases

Correct answer: Respect the competent adult's wishes while offering support and information, unless a mandatory reporting law applies

For competent adults, you generally respect their autonomy and offer support unless specific mandatory reporting laws apply.

Question 119: A GP has been treating a patient for several years. The patient sends the GP a 'friend request' on a personal social media account. The GP's profile contains photos of their family and social activities. According to the Medical Board of Australia's Code of Conduct and guidelines on professional boundaries, what is the most appropriate response?

Accept the request but change privacy settings to limit what the patient can see.
Accept the request, as declining could damage the therapeutic relationship.
Ignore the request and do not mention it at the next consultation.
Politely decline the request, explaining the need to maintain a professional doctor-patient relationship. (Correct answer)

Correct answer: Politely decline the request, explaining the need to maintain a professional doctor-patient relationship.

The Medical Board of Australia's 'Good Medical Practice: A Code of Conduct for Doctors in Australia' requires doctors to maintain professional boundaries. Interacting with current patients on personal social media blurs these boundaries and is strongly discouraged. The most appropriate action is to politely decline and, if necessary, explain that this is standard professional practice to keep the doctor-patient relationship clear and therapeutic. Accepting, even with modified privacy settings, can still lead to boundary violations.

Question 120: In the WHO surgical safety checklist, when is the 'time out' performed?

Only if a complication occurs
After the patient leaves theatre
During sign-in only
Before skin incision (Correct answer)

Correct answer: Before skin incision

The 'time out' occurs immediately before incision to confirm patient, site and procedure.

Question 121: A woman has a malar 'butterfly' rash, photosensitivity, arthralgia and a positive ANA. What is the most likely diagnosis?

Dermatomyositis
Rosacea
Sarcoidosis
Systemic lupus erythematosus (Correct answer)

Correct answer: Systemic lupus erythematosus

A photosensitive malar rash with arthralgia and positive ANA suggests SLE.

Question 122: A 65-year-old reports brief recurrent stabbing pains in the cheek triggered by chewing and touching the face. What is the most likely diagnosis?

Dental abscess
Trigeminal neuralgia (Correct answer)
Cluster headache
Temporal arteritis

Correct answer: Trigeminal neuralgia

Brief, severe, electric-shock facial pain triggered by light touch or chewing is characteristic of trigeminal neuralgia.

Question 123: A 6-week-old presents with non-bilious projectile vomiting and a palpable olive-shaped epigastric mass. What is the most likely diagnosis?

Gastro-oesophageal reflux
Duodenal atresia
Malrotation with volvulus
Pyloric stenosis (Correct answer)

Correct answer: Pyloric stenosis

Non-bilious projectile vomiting with a palpable olive in a baby around 4-8 weeks is classic for hypertrophic pyloric stenosis.

Question 124: A 70-year-old presents with fatigue, bone pain, hypercalcaemia, and serum protein electrophoresis showing an M-spike. Bone marrow biopsy shows 30% plasma cells. What is the diagnosis?

Monoclonal gammopathy of undetermined significance (MGUS)
Waldenström macroglobulinaemia
Chronic lymphocytic leukaemia
Multiple myeloma (Correct answer)

Correct answer: Multiple myeloma

Multiple myeloma is defined by >10% clonal plasma cells in bone marrow plus end-organ damage (hypercalcaemia, renal failure, anaemia, or bone lesions — CRAB criteria).

Question 125: What is the first-line treatment for ileocolic intussusception in a stable child without peritonitis?

Nasogastric decompression alone
Oral rehydration and observation
Air or contrast enema reduction (Correct answer)
Immediate laparotomy

Correct answer: Air or contrast enema reduction

Non-operative reduction with an air (pneumatic) or contrast enema is first-line when there are no signs of perforation or peritonitis.

Question 126: A child develops acute kidney injury, microangiopathic haemolytic anaemia and thrombocytopenia after bloody diarrhoea. What is the diagnosis?

Sepsis
Acute glomerulonephritis
Henoch-Schönlein purpura
Haemolytic uraemic syndrome (Correct answer)

Correct answer: Haemolytic uraemic syndrome

The triad of AKI, haemolytic anaemia and thrombocytopenia after E. coli O157 diarrhoea is haemolytic uraemic syndrome.

Question 127: Which of the following Produces greatest ATP?

Krebs cycle
Oxidative Phosphorylation (Correct answer)
Glycolysis
Fermentation

Correct answer: Oxidative Phosphorylation

Oxidative phosphorylation is the stage of cellular respiration that produces the most ATP. It involves the electron transport chain and chemiosmosis, where the energy from electrons carried by NADH and FADH2 is used to generate a large amount of ATP through ATP synthase. Glycolysis and the Krebs cycle produce only a small amount of ATP directly.

Question 128: A 35-year-old with infertility has confirmed bilateral tubal blockage. What is the most appropriate treatment to achieve pregnancy?

Clomiphene citrate
Metformin
Intrauterine insemination
In vitro fertilisation (IVF) (Correct answer)

Correct answer: In vitro fertilisation (IVF)

Bilateral tubal blockage bypasses the tubes, so IVF is the treatment of choice for conception.

Question 129: A child presents with a salmon-pink, erythematous rash, high spiking fevers and arthritis. Which condition is most likely?

Rheumatic fever
Kawasaki disease
Systemic juvenile idiopathic arthritis (Correct answer)
Henoch-Schonlein purpura

Correct answer: Systemic juvenile idiopathic arthritis

Spiking fevers with an evanescent salmon-pink rash and arthritis indicate systemic JIA (Still disease).

Question 130: A patient with acute coronary syndrome receives fibrinolysis. Which finding best indicates successful reperfusion?

Onset of chest pain
Widening QRS complex
Rise in troponin
Resolution of ST elevation by more than 50% (Correct answer)

Correct answer: Resolution of ST elevation by more than 50%

Greater than 50% resolution of ST elevation within 60-90 minutes indicates successful reperfusion.

Question 131: A 24-year-old woman reports recurrent episodes of intense fear, palpitations, sweating and a sense of impending doom lasting about 10 minutes, with no medical cause found. What is the most likely diagnosis?

Hyperthyroidism
Panic disorder (Correct answer)
Generalised anxiety disorder
Phaeochromocytoma

Correct answer: Panic disorder

Recurrent discrete episodes of intense fear peaking within minutes, with no organic cause, characterise panic disorder.

Question 132: A postmenopausal woman presents with vaginal bleeding. What is the most important investigation?

Cervical smear
Pregnancy test
Transvaginal ultrasound and endometrial sampling (Correct answer)
Vaginal pH testing

Correct answer: Transvaginal ultrasound and endometrial sampling

Postmenopausal bleeding requires endometrial assessment to exclude endometrial carcinoma.

Question 133: A 63-year-old heavy smoker and drinker presents with progressive hoarseness, odynophagia, referred otalgia, and a palpable neck mass. Laryngoscopy reveals a supraglottic mass. Which investigation is most important for staging?

Plain chest radiograph alone
Ultrasound of the neck
MRI of the brain only
CT scan of the neck, chest, and upper abdomen with contrast (Correct answer)

Correct answer: CT scan of the neck, chest, and upper abdomen with contrast

Contrast-enhanced CT of the neck, chest, and abdomen is essential for staging laryngeal carcinoma, assessing local tumour extent, regional lymph node involvement, and distant metastases to guide treatment planning.

Question 134: A 34-year-old woman is diagnosed with her first episode of moderate Major Depressive Disorder. She has no other medical or psychiatric comorbidities and is not pregnant. According to the Royal Australian and New Zealand College of Psychiatrists (RANZCP) guidelines, which of the following is considered an appropriate first-line treatment option?

Lithium carbonate.
Electroconvulsive therapy (ECT).
A benzodiazepine such as diazepam.
A selective serotonin reuptake inhibitor (SSRI) such as sertraline. (Correct answer)

Correct answer: A selective serotonin reuptake inhibitor (SSRI) such as sertraline.

For moderate Major Depressive Disorder, RANZCP guidelines recommend either an evidence-based psychotherapy (like CBT or IPT) or a recognised antidepressant as first-line treatment. Selective serotonin reuptake inhibitors (SSRIs) are a common and appropriate first-line pharmacological choice due to their efficacy and tolerability profile. ECT is reserved for severe, treatment-resistant, or psychotic depression. Benzodiazepines are not a first-line treatment for depression and are used for short-term management of anxiety. Lithium is primarily a mood stabiliser used for bipolar disorder.

Question 135: A 25-year-old presents with painless cervical lymphadenopathy, fever, night sweats, and weight loss. Biopsy shows Reed-Sternberg cells. What is the most likely diagnosis?

Non-Hodgkin lymphoma
Hodgkin lymphoma (Correct answer)
Sarcoidosis
Infectious mononucleosis

Correct answer: Hodgkin lymphoma

Reed-Sternberg cells are pathognomonic of Hodgkin lymphoma, which typically presents with B symptoms and mediastinal or cervical lymphadenopathy.

Question 136: The fat RQ is ____________

less than one (Correct answer)
infinity
more than one
one

Correct answer: less than one

The Respiratory Quotient (RQ) for fats is typically less than one (around 0.7). This is because fats have a lower oxygen content relative to their carbon and hydrogen atoms compared to carbohydrates, meaning more oxygen is required for their complete oxidation, resulting in a lower CO2 produced to O2 consumed ratio.

Question 137: A 45-year-old woman presents with a 2-week history of epigastric pain, nausea, and early satiety. A urea breath test is positive for Helicobacter pylori. She has no known drug allergies. According to current Australian Therapeutic Guidelines, which of the following is the most appropriate first-line eradication therapy?

A proton pump inhibitor, clarithromycin, and metronidazole for 14 days.
A proton pump inhibitor, amoxicillin, and metronidazole for 7 days.
Bismuth quadruple therapy for 14 days.
A proton pump inhibitor, amoxicillin, and clarithromycin for 7-14 days. (Correct answer)

Correct answer: A proton pump inhibitor, amoxicillin, and clarithromycin for 7-14 days.

Current Australian guidelines recommend standard triple therapy as the first-line treatment for H. pylori eradication. This regimen consists of a proton pump inhibitor (PPI) combined with amoxicillin and clarithromycin. The recommended duration is typically 7 to 14 days, with 14 days potentially offering higher eradication rates. While other regimens exist, they are generally considered for second-line therapy or in areas with high clarithromycin resistance.

Question 138: A 50-year-old woman with a thyroid nodule has a suppressed TSH and an increased radioactive iodine uptake confined to the nodule. What is this lesion most likely to be?

Hashimoto thyroiditis
Multinodular goitre
Papillary carcinoma
Toxic adenoma (Correct answer)

Correct answer: Toxic adenoma

An autonomously functioning ('hot') nodule with increased focal uptake and suppressed TSH is a toxic adenoma and is almost always benign.

Question 139: A patient with systemic lupus erythematosus has low C3 and C4 levels. Which component of the immune system is primarily responsible for this finding during active disease?

T-cell mediated cytotoxicity
Natural killer cell activation
Complement consumption via immune complex deposition (Correct answer)
Mast cell degranulation

Correct answer: Complement consumption via immune complex deposition

In SLE, immune complexes deposit in tissues and activate the classical complement pathway, consuming C3 and C4.

Question 140: A postoperative patient develops sudden pleuritic chest pain, dyspnoea and tachycardia on day 4. What is the most likely diagnosis?

Pulmonary embolism (Correct answer)
Urinary retention
Wound infection
Anastomotic leak

Correct answer: Pulmonary embolism

Sudden pleuritic chest pain with dyspnoea and tachycardia postoperatively strongly suggests pulmonary embolism.

Question 141: A trauma patient has distended neck veins, hypotension and muffled heart sounds. What is the diagnosis?

Neurogenic shock
Cardiac tamponade (Correct answer)
Tension pneumothorax
Massive haemothorax

Correct answer: Cardiac tamponade

Beck's triad of hypotension, raised JVP and muffled heart sounds indicates cardiac tamponade.

Question 142: A 58-year-old man with a 40-pack-year smoking history is undergoing a laparotomy. In the context of wound healing, which of the following phases is most directly impaired by the physiological effects of cigarette smoking?

Haemostasis
Remodelling phase
Inflammatory phase
Proliferative phase (Correct answer)

Correct answer: Proliferative phase

The proliferative phase of wound healing (days 3-14) is characterised by fibroblast proliferation, collagen synthesis, and angiogenesis. Cigarette smoking severely impairs this phase. Nicotine is a potent vasoconstrictor, and carbon monoxide reduces the oxygen-carrying capacity of haemoglobin. The resulting tissue hypoxia directly inhibits fibroblast activity and the synthesis of collagen, which is essential for wound strength. While smoking can have negative effects on all phases, its most pronounced impact is on the oxygen-dependent processes of proliferation and matrix deposition.

Question 143: According to the National Cervical Screening Program in Australia, what is the recommended primary screening test and interval for an asymptomatic 30-year-old woman with no history of cervical abnormalities?

Co-testing with HPV and cytology every 3 years
Human Papillomavirus (HPV) DNA test every 5 years (Correct answer)
Liquid-based cytology (Pap smear) every 2 years
Visual inspection with acetic acid (VIA) annually

Correct answer: Human Papillomavirus (HPV) DNA test every 5 years

The current Australian National Cervical Screening Program recommends primary screening with a Human Papillomavirus (HPV) DNA test every 5 years for asymptomatic women and people with a cervix aged 25 to 74. This replaced the 2-yearly Pap smear (cytology) program. If the HPV test detects an oncogenic HPV type, reflex liquid-based cytology (LBC) is performed on the same sample to triage management.

Question 144: A 5-year-old is found on routine screening to have best corrected visual acuity of 6/6 in the right eye and 6/60 in the left eye with no structural abnormality. What is the most effective treatment for the left eye?

Atropine drops to both eyes
Corrective lenses alone
Surgery on the left eye
Patching the right (good) eye for several hours per day (Correct answer)

Correct answer: Patching the right (good) eye for several hours per day

Amblyopia is treated by patching the stronger eye to force use of the amblyopic eye, stimulating visual cortex development during the critical period of visual plasticity.

Question 145: A 61-year-old smoker presents with 8 weeks of progressive hoarseness. Flexible laryngoscopy reveals a lesion on the left true vocal cord with impaired mobility. What is the single most important next step in management?

Antifungal therapy for presumed candidiasis
Microlaryngoscopy and biopsy under general anaesthesia (Correct answer)
Proton pump inhibitors for suspected laryngopharyngeal reflux
Voice rest for 4 weeks and reassessment

Correct answer: Microlaryngoscopy and biopsy under general anaesthesia

Persistent hoarseness beyond 3 weeks in a smoker with a laryngeal lesion requires urgent microlaryngoscopy and biopsy to obtain histological diagnosis and exclude laryngeal carcinoma.

Question 146: A 26-year-old has a smear showing low-grade squamous intraepithelial lesion with positive high-risk HPV. What is the usual next step?

Colposcopy (Correct answer)
Endometrial biopsy
Repeat smear in 5 years
Immediate hysterectomy

Correct answer: Colposcopy

Abnormal cytology with high-risk HPV is referred for colposcopy to directly assess the cervix.

Question 147: A patient gives you an expensive gift after successful treatment. The most appropriate response is to:

Always refuse all gifts rudely
Use professional judgement; small tokens may be acceptable but large gifts risk compromising the relationship and should generally be declined (Correct answer)
Accept any gift regardless of value
Accept it only if cash

Correct answer: Use professional judgement; small tokens may be acceptable but large gifts risk compromising the relationship and should generally be declined

Modest tokens of thanks may be acceptable, but significant gifts can create obligations and undermine professional boundaries.

Question 148: What is the mainstay of management for bronchiolitis in a hospitalised infant?

Nebulised salbutamol
Systemic corticosteroids
Supportive care with oxygen and feeding support (Correct answer)
Oral antibiotics

Correct answer: Supportive care with oxygen and feeding support

Bronchiolitis management is supportive—oxygen, hydration and feeding support—as bronchodilators and steroids are not beneficial.

Question 149: Which finding is most consistent with an anastomotic leak after colorectal surgery on day 5?

Immediate brisk haematemesis
Fever, tachycardia and peritonism (Correct answer)
Painless jaundice
Isolated hyperkalaemia

Correct answer: Fever, tachycardia and peritonism

Anastomotic leaks typically present around day 5 with sepsis signs and peritoneal irritation.

Question 150: Which drug is given to reduce splanchnic blood flow in acute variceal bleeding?

Terlipressin (Correct answer)
Propranolol immediately
Omeprazole
Tranexamic acid

Correct answer: Terlipressin

Terlipressin causes splanchnic vasoconstriction, reducing portal pressure and variceal bleeding.

AMC CAT MCQ Exam

The Australian Medical Council Computer Adaptive Test assesses internationally trained medical graduates across core clinical disciplines for eligibility to practise medicine in Australia.

150

Questions

210 min

Time Limit

50%

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