AMC CAT MCQ Exam — Questions and Answers

Question 1: A woman has a malar 'butterfly' rash, photosensitivity, arthralgia and a positive ANA. What is the most likely diagnosis?

Sarcoidosis
Rosacea
Systemic lupus erythematosus (Correct answer)
Dermatomyositis

Correct answer: Systemic lupus erythematosus

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

Question 2: A 70-year-old with atrial fibrillation develops sudden painless monocular vision loss. Fundoscopy shows a pale, oedematous retina with a 'cherry red spot' at the fovea. What is the diagnosis?

Vitreous haemorrhage
Central retinal artery occlusion (Correct answer)
Central retinal vein occlusion
Anterior ischaemic optic neuropathy

Correct answer: Central retinal artery occlusion

Central retinal artery occlusion causes inner retinal ischaemia, producing a pale retina with a cherry red spot at the fovea where the choroidal circulation preserves the thinner foveal tissue.

Question 3: A study finds an association between coffee drinking and lung cancer, but smoking is more common among coffee drinkers. Smoking is best described as a:

Mediator
Effect modifier
Collider
Confounder (Correct answer)

Correct answer: Confounder

Smoking is associated with both the exposure and the outcome and is not on the causal pathway, making it a confounder.

Question 4: 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?

Give fresh frozen plasma alone
Administer platelet transfusion alone
Administer heparin to prevent further clotting
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 5: A patient with X-linked agammaglobulinemia (Bruton's disease) would be most susceptible to which type of infection?

Fungal infections
Encapsulated bacterial infections (Correct answer)
Parasitic infections
Intracellular viral 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 6: What is the most serious complication of untreated Kawasaki disease?

Hearing loss
Renal failure
Coronary artery aneurysms (Correct answer)
Liver cirrhosis

Correct answer: Coronary artery aneurysms

Kawasaki disease can cause coronary artery aneurysms, which is why prompt treatment is essential.

Question 7: A 55-year-old woman with rheumatoid arthritis on long-term NSAIDs develops a rising creatinine, sterile pyuria, eosinophiluria and a rash. What is the most likely renal diagnosis?

Acute interstitial nephritis (Correct answer)
Minimal change disease
Acute tubular necrosis
Membranous nephropathy

Correct answer: Acute interstitial nephritis

Drug-induced acute interstitial nephritis classically presents with rash, eosinophiluria and rising creatinine.

Question 8: What is the most reliable clinical sign of established compartment syndrome in a limb?

Absent distal pulses early
Pain on passive stretch out of proportion to injury (Correct answer)
Reduced capillary refill alone
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 9: What is the correct immediate management of a suspected tension pneumothorax?

Await a chest X-ray before acting
Urgent chest CT first
Immediate needle or finger thoracostomy (Correct answer)
Start oral antibiotics

Correct answer: Immediate needle or finger thoracostomy

Tension pneumothorax is a clinical diagnosis requiring immediate decompression before imaging.

Question 10: 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 vaccination alone
Tenofovir prophylaxis
Hepatitis B immune globulin (HBIG) plus hepatitis B vaccination (Correct answer)
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 11: The diaphragm _______ during inspiration.

No change
Relaxes
Contracts (Correct answer)
Expands

Correct answer: Contracts

During inspiration (inhalation), the diaphragm contracts and flattens, moving downwards. This action increases the volume of the thoracic cavity, which in turn decreases the pressure within the lungs. The resulting pressure gradient causes air to flow into the lungs.

Question 12: A patient with chronic myeloid leukaemia (CML) is found to have the Philadelphia chromosome t(9;22). Which molecular target does imatinib inhibit?

BCR-ABL tyrosine kinase (Correct answer)
BCL-2
VEGFR
CD20

Correct answer: BCR-ABL tyrosine kinase

Imatinib is a selective BCR-ABL tyrosine kinase inhibitor that blocks the constitutively active kinase produced by the Philadelphia chromosome translocation in CML.

Question 13: Which paraneoplastic syndrome is most associated with small cell lung carcinoma causing hyponatraemia?

Carcinoid syndrome
Cushing syndrome from ectopic insulin
SIADH (Correct answer)
Hypercalcaemia from PTHrP

Correct answer: SIADH

Small cell lung cancer commonly causes SIADH, leading to hyponatraemia.

Question 14: An elderly man presents after a fall with a shortened, externally rotated leg and hip pain. What is the most likely injury?

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

Correct answer: Fractured neck of femur

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

Question 15: A labouring woman's CTG shows late decelerations with reduced variability. What does this most likely indicate?

Fetal hypoxia and uteroplacental insufficiency (Correct answer)
Cord compression only
Normal fetal sleep cycle
Maternal pyrexia

Correct answer: Fetal hypoxia and uteroplacental insufficiency

Late decelerations with reduced variability suggest fetal hypoxia from uteroplacental insufficiency, warranting action.

Question 16: A 45-year-old reports heavy menstrual bleeding with a bulky, irregular uterus on examination. What is the most likely diagnosis?

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

Correct answer: Uterine fibroids

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

Question 17: What is the most appropriate prophylaxis for a woman with previous early-onset pre-eclampsia in her next pregnancy?

Bed rest from 20 weeks
High-dose folic acid
Routine antihypertensives
Low-dose aspirin from the first trimester (Correct answer)

Correct answer: Low-dose aspirin from the first trimester

Low-dose aspirin started before 16 weeks reduces recurrence risk in women with prior pre-eclampsia.

Question 18: A 72-year-old man presents with a 2-year history of progressive difficulty with his mobility. His wife reports he has a persistent tremor in his right hand which is most noticeable when he is watching television but improves when he reaches for his cup. On examination, you note a lack of facial expression, a slow, shuffling gait, and 'cogwheel' rigidity in his right arm. Which of the following is the most likely diagnosis?

Drug-induced parkinsonism
Multiple system atrophy
Essential tremor
Parkinson's disease (Correct answer)

Correct answer: Parkinson's disease

This patient presents with the classic triad of Parkinson's disease: a resting tremor, bradykinesia (slowness of movement, evidenced by shuffling gait and lack of facial expression), and rigidity. The asymmetric onset and the nature of the tremor (present at rest, improving with action) are highly characteristic of Parkinson's disease. Essential tremor is an action tremor. While drug-induced parkinsonism can present similarly, the progressive history without a clear offending medication makes it less likely. Multiple system atrophy often has more prominent autonomic features early on.

Question 19: A breast cancer patient is found to have HER2 gene amplification. Which targeted therapy specifically targets this receptor?

Rituximab
Trastuzumab (Correct answer)
Cetuximab
Bevacizumab

Correct answer: Trastuzumab

Trastuzumab (Herceptin) is a monoclonal antibody targeting HER2 (ErbB2), used in HER2-positive breast and gastric cancers.

Question 20: Which of the following is considered a primary 'alarm' symptom in a patient with gastro-oesophageal reflux disease (GORD) that warrants urgent endoscopic investigation?

Dysphagia. (Correct answer)
Regurgitation after meals.
Epigastric burning relieved by antacids.
Waterbrash.

Correct answer: Dysphagia.

Dysphagia (difficulty swallowing) is a significant 'red flag' or 'alarm' symptom in patients with GORD. It may indicate a complication such as an oesophageal stricture or malignancy and requires urgent investigation, typically with an endoscopy. While the other symptoms are characteristic of GORD, they are not considered alarm features in the absence of other signs.

Question 21: A p-value of 0.04 in a study comparing two treatments means there is approximately a 4% probability that:

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

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 22: A 50-year-old woman post-chemotherapy presents with fever (38.5°C) and an absolute neutrophil count of 0.3 × 10⁹/L. What is the most appropriate immediate management?

Await blood culture results before starting antibiotics
Oral ciprofloxacin as outpatient
Start empirical broad-spectrum intravenous antibiotics immediately (Correct answer)
Administer G-CSF alone

Correct answer: Start empirical broad-spectrum intravenous antibiotics immediately

Febrile neutropenia is a medical emergency; empirical broad-spectrum IV antibiotics (e.g., piperacillin-tazobactam) must be started immediately without waiting for culture results.

Question 23: 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?

Raloxifene
Teriparatide
Alendronate (Correct answer)
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 24: 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?

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

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 25: 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?

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

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 26: What is the first-line treatment for minimal change nephrotic syndrome in children?

Diuretics alone
ACE inhibitors
Corticosteroids (prednisolone) (Correct answer)
Cyclophosphamide

Correct answer: Corticosteroids (prednisolone)

Most childhood minimal change nephrotic syndrome responds to a course of oral corticosteroids.

Question 27: 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?

Brain tumour
Hypoglycaemia
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 28: Which secondary cause of hypertension should be suspected in a young patient with hypokalaemia and metabolic alkalosis?

Hypothyroidism
Diabetes insipidus
Primary hyperaldosteronism (Correct answer)
Iron deficiency anaemia

Correct answer: Primary hyperaldosteronism

Primary hyperaldosteronism (Conn syndrome) classically causes hypertension with hypokalaemia and alkalosis.

Question 29: A 28-year-old traveler returns from Southeast Asia with fever, chills, and rigors every 48 hours. Blood film shows ring forms and banana-shaped gametocytes. Which Plasmodium species is most likely responsible?

Plasmodium ovale
Plasmodium malariae
Plasmodium falciparum (Correct answer)
Plasmodium vivax

Correct answer: Plasmodium falciparum

Plasmodium falciparum produces banana-shaped (crescent) gametocytes and is the most dangerous malaria species.

Question 30: A 42-year-old presents with recurrent episodes of vertigo lasting 2-3 hours, accompanied by fluctuating low-frequency sensorineural hearing loss, tinnitus, and aural fullness in the left ear. What is the most likely diagnosis?

Meniere's disease (Correct answer)
Benign paroxysmal positional vertigo
Vestibular neuritis
Vestibular schwannoma

Correct answer: Meniere's disease

Meniere's disease is characterized by the classic tetrad of episodic vertigo, fluctuating sensorineural hearing loss, tinnitus, and aural fullness due to endolymphatic hydrops.

Question 31: A child with drooling, high fever, muffled voice and a tripod posture who avoids lying flat most likely has which condition?

Asthma
Croup
Bronchiolitis
Epiglottitis (Correct answer)

Correct answer: Epiglottitis

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

Question 32: A doctor has a sexual relationship with a current patient. Under professional codes this is:

Acceptable after one consultation
A serious breach of professional boundaries and notifiable conduct (Correct answer)
Only a problem if the patient complains
Acceptable if both consent

Correct answer: A serious breach of professional boundaries and notifiable conduct

Sexual relationships with current patients are a serious boundary violation and constitute notifiable conduct.

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

Respiratory alkalosis
Metabolic acidosis with high anion gap
Hyperchloraemic acidosis
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 75-year-old develops gradual cognitive decline with prominent early memory loss and no focal neurological signs. What is the most likely diagnosis?

Frontotemporal dementia
Vascular dementia
Alzheimer's disease (Correct answer)
Lewy body dementia

Correct answer: Alzheimer's disease

Insidious progressive memory loss without early focal deficits is most consistent with Alzheimer's disease.

Question 35: What is the most appropriate first investigation when a young child presents with a first febrile urinary tract infection?

CT abdomen
Urine culture before starting antibiotics (Correct answer)
Renal biopsy
Cystoscopy

Correct answer: Urine culture before starting antibiotics

A clean urine sample for microscopy and culture should be obtained before antibiotics to confirm the diagnosis.

Question 36: Which feature most strongly suggests Legionella pneumonia rather than typical pneumonia?

Rapid response to penicillin
Productive rusty sputum
Localised pleuritic chest pain only
Hyponatraemia with confusion and diarrhoea (Correct answer)

Correct answer: Hyponatraemia with confusion and diarrhoea

Legionella classically causes hyponatraemia, neurological features and gastrointestinal symptoms.

Question 37: A pigmented skin lesion shows asymmetry, irregular borders, colour variation and a diameter over 6mm. What is the most concerning diagnosis?

Seborrhoeic keratosis
Dermatofibroma
Malignant melanoma (Correct answer)
Solar lentigo

Correct answer: Malignant melanoma

The ABCDE criteria raise strong suspicion of malignant melanoma.

Question 38: A CURB-65 score of 4 in a patient with pneumonia indicates which management approach?

Outpatient follow-up only
No antibiotics needed
Consideration of ICU admission (Correct answer)
Home treatment with oral antibiotics

Correct answer: Consideration of ICU admission

A high CURB-65 score (3–5) indicates severe pneumonia warranting hospital and possible ICU care.

Question 39: A 14-month-old girl presents after a 2-minute generalised tonic-clonic seizure. Her parents report she had a fever of 39.2°C just prior to the event. She has now returned to her baseline neurological state, although she is drowsy. There is no history of previous seizures or neurological problems. On examination, she has a viral-appearing upper respiratory tract infection but no signs of meningism. What is the most important piece of advice to give her parents regarding this event?

Prophylactic antipyretics will prevent future febrile seizures.
An urgent EEG is required to rule out epilepsy.
She will need to start long-term anti-epileptic medication.
This was a simple febrile seizure, which is generally benign and does not cause brain damage. (Correct answer)

Correct answer: This was a simple febrile seizure, which is generally benign and does not cause brain damage.

This is a classic presentation of a simple febrile seizure: a generalised seizure lasting less than 15 minutes in a febrile child aged 6 months to 6 years with a rapid return to baseline. The most crucial part of management is parental reassurance and education. Simple febrile seizures are benign, do not cause long-term neurological damage, and do not significantly increase the risk of epilepsy. Routine investigations like an EEG are not indicated. While antipyretics can improve comfort, they have not been shown to prevent the recurrence of febrile seizures. Long-term anti-epileptic medication is not recommended.

Question 40: 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
Cryptosporidium parvum (Correct answer)
Giardia lamblia
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 41: A patient on long-term steroids requires major surgery. What perioperative concern is most important?

Need to stop steroids 24 hours prior
Risk of adrenal crisis requiring stress-dose steroids (Correct answer)
Increased risk of hypoglycaemia
Reduced wound infection risk

Correct answer: Risk of adrenal crisis requiring stress-dose steroids

Chronic steroid use suppresses the adrenal axis, requiring stress-dose cover to prevent perioperative adrenal crisis.

Question 42: A child develops acute kidney injury, microangiopathic haemolytic anaemia and thrombocytopenia after bloody diarrhoea. What is the diagnosis?

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

Correct answer: Haemolytic uraemic syndrome

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

Question 43: The maximum expiration of the lungs after deep inspiration is referred to as ________

Vital capacity (Correct answer)
Inspiratory capacity
Total lung capacity
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 44: Which prevention strategy targets the whole population rather than high-risk individuals?

Screening of contacts
High-risk strategy
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 45: _________ is controlled respiration.

Cerebellum
Medulla oblongata (Correct answer)
Hypothalamus
Cerebrum

Correct answer: Medulla oblongata

The medulla oblongata, located in the brainstem, contains the primary respiratory control centers. These centers automatically regulate the rhythm and depth of breathing, responding to chemical changes in the blood such as CO2 and O2 levels, thereby controlling involuntary respiration.

Question 46: 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.
Ignore the request and do not mention it at the next consultation.
Accept the request, as declining could damage the therapeutic relationship.
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 47: A 35-year-old with infertility has confirmed bilateral tubal blockage. What is the most appropriate treatment to achieve pregnancy?

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

Correct answer: In vitro fertilisation (IVF)

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

Question 48: Which medication provides symptomatic relief of acute angina by venodilation and reducing preload?

Oral aspirin
Ramipril
Atorvastatin
Sublingual glyceryl trinitrate (Correct answer)

Correct answer: Sublingual glyceryl trinitrate

Sublingual GTN rapidly relieves angina by reducing preload through venodilation.

Question 49: A woman on the combined oral contraceptive pill develops a unilateral swollen, painful calf. What is the priority action?

Switch to a higher oestrogen pill
Reassure and continue the pill
Stop the pill and investigate for DVT (Correct answer)
Increase the pill dose

Correct answer: Stop the pill and investigate for DVT

Combined oral contraceptives increase venous thromboembolism risk, so suspected DVT requires stopping the pill and urgent investigation.

Question 50: Which VTE prophylaxis is appropriate for a high-risk patient after major abdominal cancer surgery?

No prophylaxis if mobile
Warfarin started immediately at full dose
Low-molecular-weight heparin plus mechanical prophylaxis (Correct answer)
Aspirin alone

Correct answer: Low-molecular-weight heparin plus mechanical prophylaxis

High-risk cancer surgery patients need combined pharmacological and mechanical VTE prophylaxis.

Question 51: A doctor posts a deidentified but recognisable patient case on social media. Why is this an ethical problem?

Patients may still be identifiable, breaching confidentiality and consent requirements (Correct answer)
Social media is always prohibited for doctors
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 52: On the inner surface of bronchioles and fallopian tubules, epithelial tissues are ________.

Glandular
Squamous
Ciliated (Correct answer)
Cuboidal

Correct answer: Ciliated

Both the inner surface of bronchioles in the respiratory system and the fallopian tubules in the reproductive system are lined with ciliated epithelial tissue. The cilia are hair-like projections that rhythmically beat to move mucus and trapped particles out of the respiratory tract, and to propel the ovum in the fallopian tubes.

Question 53: A 40-year-old patient is diagnosed with primary adrenal insufficiency (Addison's disease). Which of the following electrolyte patterns is most characteristically seen in this condition?

Hyponatraemia, hypokalaemia, metabolic acidosis
Hypernatraemia, hyperkalaemia, metabolic alkalosis
Hypernatraemia, hypokalaemia, metabolic alkalosis
Hyponatraemia, hyperkalaemia, metabolic acidosis (Correct answer)

Correct answer: Hyponatraemia, hyperkalaemia, metabolic acidosis

Primary adrenal insufficiency (Addison's disease) involves the destruction of the adrenal cortex, leading to a deficiency of both cortisol and aldosterone. Aldosterone deficiency impairs the kidney's ability to reabsorb sodium and excrete potassium and hydrogen ions. [5, 29] This results in the characteristic electrolyte disturbances of hyponatraemia (low sodium), hyperkalaemia (high potassium), and a non-anion gap metabolic acidosis. [5, 36]

Question 54: A 75-year-old man develops an acute kidney injury (AKI) 48 hours after a hypotensive episode during surgery. His creatinine has risen from 80 µmol/L to 250 µmol/L and he is oliguric. A urinary catheter is in situ and draining freely. Which set of urinary indices would be most suggestive of pre-renal azotaemia rather than established acute tubular necrosis (ATN)?

Urine osmolality >500 mOsm/kg, Urine sodium <20 mmol/L, FENa <1% (Correct answer)
Urine osmolality <350 mOsm/kg, Urine sodium >40 mmol/L, FENa >2%
Eosinophils present in the urine sediment
Presence of red cell casts in urine microscopy

Correct answer: Urine osmolality >500 mOsm/kg, Urine sodium <20 mmol/L, FENa <1%

In pre-renal azotaemia, the kidney is hypoperfused but tubular function remains intact. The tubules respond appropriately by avidly reabsorbing sodium and water to conserve volume. This leads to a low urine sodium (<20 mmol/L), a low Fractional Excretion of Sodium (FENa <1%), and concentrated urine (osmolality >500 mOsm/kg). [1, 9] In contrast, in established Acute Tubular Necrosis (ATN), the damaged tubules lose their ability to concentrate urine and reabsorb sodium, resulting in a high urine sodium (>40 mmol/L), a high FENa (>2%), and isosthenuria (urine osmolality ~300-350 mOsm/kg). [34]

Question 55: A 60-year-old with long-standing alcohol use presents confused, with ophthalmoplegia and ataxia. What is the most appropriate immediate treatment?

Intravenous glucose alone
Intravenous thiamine before any glucose (Correct answer)
Oral folic acid
Benzodiazepine sedation only

Correct answer: Intravenous thiamine before any glucose

Wernicke's encephalopathy requires parenteral thiamine before glucose to avoid precipitating irreversible damage.

Question 56: A relative risk of 1.0 with a 95% confidence interval of 0.85 to 1.18 indicates the association is:

Confounded by age
Strongly harmful
Not statistically significant (Correct answer)
Strongly protective

Correct answer: Not statistically significant

A confidence interval crossing 1.0 means the result is not statistically significant.

Question 57: Which organism is the most common cause of pelvic inflammatory disease in young sexually active women?

Escherichia coli
Chlamydia trachomatis (Correct answer)
Gardnerella vaginalis
Candida albicans

Correct answer: Chlamydia trachomatis

Chlamydia trachomatis is the leading cause of PID, often asymptomatic until complications arise.

Question 58: What is the lethal triad in trauma that damage control surgery seeks to prevent?

Anaemia, jaundice and ascites
Hypoxia, hypercapnia and bradycardia
Hypertension, hyperglycaemia and fever
Hypothermia, acidosis and coagulopathy (Correct answer)

Correct answer: Hypothermia, acidosis and coagulopathy

The lethal triad of hypothermia, acidosis and coagulopathy worsens bleeding and mortality in trauma.

Question 59: A 45-year-old woman presents with episodic palpitations, headache, and sweating with paroxysmal hypertension. Which diagnosis should be considered?

Hyperthyroidism
Panic disorder
Phaeochromocytoma (Correct answer)
Essential hypertension

Correct answer: Phaeochromocytoma

The triad of headache, palpitations, and sweating with paroxysmal hypertension suggests phaeochromocytoma.

Question 60: 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?

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

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

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

Question 61: A patient's records are subpoenaed by a court. What is the correct response?

Comply with the valid legal order while disclosing only what is required (Correct answer)
Release everything to everyone who asks
Destroy the records
Refuse to release anything to protect confidentiality

Correct answer: Comply with the valid legal order while disclosing only what is required

A valid court order is a legal exception to confidentiality, and you should disclose only the information required.

Question 62: Which suture material is most appropriate for a contaminated abdominal wound closure?

Braided absorbable polyglactin
Braided non-absorbable silk
Stainless steel wire only
Monofilament absorbable (Correct answer)

Correct answer: Monofilament absorbable

Monofilament absorbable sutures harbour fewer bacteria than braided material in contaminated fields.

Question 63: A postoperative patient develops sudden pleuritic chest pain, dyspnoea and tachycardia on day 4. What is the most likely diagnosis?

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

Correct answer: Pulmonary embolism

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

Question 64: 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?

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

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 65: 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?

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

Correct answer: Iron deficiency anaemia

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

Question 66: A patient with a witnessed generalised tonic-clonic seizure has now been convulsing continuously for more than five minutes. What is the most appropriate first-line drug?

Intravenous or buccal benzodiazepine (Correct answer)
Oral phenytoin
Intramuscular haloperidol
Intravenous mannitol

Correct answer: Intravenous or buccal benzodiazepine

Status epilepticus is treated first with a benzodiazepine to terminate the seizure.

Question 67: A woman at 38 weeks has spontaneous rupture of membranes with green-stained liquor. What does this indicate?

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

Correct answer: Meconium-stained liquor requiring closer fetal monitoring

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

Question 68: A 5-day-old, exclusively breastfed, term infant is brought for review due to increasing jaundice. The baby is feeding well, has adequate urine output, and is otherwise well. The mother is blood group O positive and the baby is A positive. A serum bilirubin level is performed. Which of the following features would most strongly suggest a pathological cause for the jaundice, rather than physiological or breast milk jaundice?

The total serum bilirubin is 220 micromol/L.
The jaundice was first noticed on day 3 of life.
A positive Direct Antiglobulin Test (Coombs' test).
The conjugated bilirubin component is 35 micromol/L. (Correct answer)

Correct answer: The conjugated bilirubin component is 35 micromol/L.

A conjugated bilirubin level greater than 20% of the total, or an absolute value >20 micromol/L, is always considered pathological and requires urgent investigation to rule out causes like biliary atresia or neonatal hepatitis. Physiological jaundice typically appears after 24 hours and peaks around day 3-5. Breast milk jaundice can cause a prolonged unconjugated hyperbilirubinaemia but the conjugated fraction remains normal. A positive Coombs' test indicates haemolysis (e.g., ABO incompatibility), which is pathological, but a raised conjugated fraction points towards a different and often more urgent set of cholestatic pathologies. Given the options, cholestasis (indicated by high conjugated bilirubin) is a major red flag.

Question 69: Which nerve is most commonly injured in a mid-shaft humeral fracture?

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

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 70: 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?

Tic disorder
Complex partial seizures
Daydreaming
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 71: A patient with severe acute pancreatitis develops a fall in serum calcium. What is the mechanism?

Vitamin D toxicity
Increased parathyroid hormone
Saponification of calcium by released fatty acids (Correct answer)
Renal calcium wasting

Correct answer: Saponification of calcium by released fatty acids

Lipase-mediated fat necrosis binds calcium to free fatty acids (saponification), lowering serum calcium.

Question 72: A patient with Parkinson's disease develops worsening tremor and rigidity after being started on a new medication for nausea. Which drug is the most likely cause?

Ondansetron
Domperidone
Cyclizine
Metoclopramide (Correct answer)

Correct answer: Metoclopramide

Metoclopramide is a central dopamine antagonist that crosses the blood-brain barrier and worsens parkinsonism.

Question 73: A 35-year-old woman presents with a 3-month history of weight loss despite an increased appetite, palpitations, and heat intolerance. On examination, she has a fine tremor and a diffusely enlarged, non-tender thyroid gland. Which of the following patterns of thyroid function tests and antibodies would be most consistent with a diagnosis of Graves' disease?

Normal TSH, Normal Free T4, High Thyroglobulin antibodies
Low TSH, High Free T4, High Free T3, Positive Thyroid Peroxidase (TPO) antibodies
High TSH, Low Free T4, Positive Thyroid Peroxidase (TPO) antibodies
Low TSH, High Free T4, High Free T3, Positive TSH Receptor Antibodies (TRAb) (Correct answer)

Correct answer: Low TSH, High Free T4, High Free T3, Positive TSH Receptor Antibodies (TRAb)

Graves' disease is an autoimmune condition where TSH receptor antibodies (TRAb) stimulate the thyroid gland, leading to excessive production of thyroid hormones (T4 and T3). This results in primary hyperthyroidism, characterized by a suppressed Thyroid-Stimulating Hormone (TSH) due to negative feedback, and elevated levels of Free T4 and Free T3. The presence of TRAb is the specific pathogenic marker for Graves' disease. While TPO antibodies can also be positive, TRAb are more specific for the diagnosis.

Question 74: A 32-year-old woman with depression on a high-dose SSRI is started on tramadol and develops agitation, clonus, hyperreflexia, tremor and fever. What is the most likely diagnosis?

Anticholinergic toxicity
Alcohol withdrawal
Serotonin syndrome (Correct answer)
Neuroleptic malignant syndrome

Correct answer: Serotonin syndrome

Clonus, hyperreflexia and agitation after adding a serotonergic drug indicate serotonin syndrome.

Question 75: 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?

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

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 76: Which feature most strongly suggests septic arthritis requiring urgent joint aspiration?

A hot, swollen joint with fever and inability to bear weight (Correct answer)
Heberden nodes
Bilateral symmetrical joint stiffness
Morning stiffness lasting 10 minutes

Correct answer: A hot, swollen joint with fever and inability to bear weight

An acutely hot, swollen, painful joint with fever is septic arthritis until proven otherwise.

Question 77: A young man presents with elevated mood, grandiosity, reduced need for sleep, rapid speech and reckless spending over the past week. What is the most likely diagnosis?

Manic episode (Correct answer)
Major depressive episode
Schizophrenia
Generalised anxiety disorder

Correct answer: Manic episode

Elevated mood, grandiosity, decreased sleep need and risky behaviour indicate a manic episode.

Question 78: A 28-year-old woman with palpitations, weight loss, tremor and a diffuse goitre has a suppressed TSH, raised free T4 and positive TSH-receptor antibodies. What is the diagnosis?

Graves disease (Correct answer)
Factitious thyrotoxicosis
Subacute thyroiditis
Toxic multinodular goitre

Correct answer: Graves disease

A diffuse goitre with TSH-receptor antibodies and thyrotoxicosis defines Graves disease.

Question 79: 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?

Valacyclovir (Correct answer)
Ribavirin
Oseltamivir
Lamivudine

Correct answer: Valacyclovir

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

Question 80: A patient with chronic productive cough of large volumes of purulent sputum and recurrent infections has tram-track opacities on imaging. What is the most likely diagnosis?

Emphysema
Bronchiectasis (Correct answer)
Pulmonary oedema
Asthma

Correct answer: Bronchiectasis

Copious purulent sputum, recurrent infection and dilated thick-walled airways indicate bronchiectasis.

Question 81: Which of the following is the recommended target for low-density lipoprotein cholesterol (LDL-C) for secondary prevention in a patient who has had an acute coronary syndrome, according to the 2025 Australian clinical guidelines?

< 2.5 mmol/L
< 1.4 mmol/L and at least a 50% reduction from baseline (Correct answer)
< 1.8 mmol/L
< 2.0 mmol/L

Correct answer: < 1.4 mmol/L and at least a 50% reduction from baseline

The 2025 Australian clinical guideline for diagnosing and managing acute coronary syndromes recommends a more aggressive LDL-C target for secondary prevention. For patients post-ACS, the target is an LDL-C level of < 1.4 mmol/L and a reduction of at least 50% from the baseline level. This reflects evidence showing further benefit from achieving the lowest possible LDL-C levels in this high-risk population. The other options represent older, less stringent targets.

Question 82: A 60-year-old man with heart failure is started on an ACE inhibitor and his creatinine rises by 40% within a week. What is the most likely explanation?

Acute interstitial nephritis
Bilateral renal artery stenosis (Correct answer)
Acute tubular necrosis
Glomerulonephritis

Correct answer: Bilateral renal artery stenosis

ACE inhibitors reduce efferent arteriolar tone and precipitate a marked creatinine rise when renal perfusion depends on it, as in bilateral renal artery stenosis.

Question 83: 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?

Generalised anxiety disorder
Panic disorder (Correct answer)
Hyperthyroidism
Phaeochromocytoma

Correct answer: Panic disorder

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

Question 84: A patient presents with blood pressure of 220/130 mmHg, headache, and papilloedema. What is this emergency called?

Essential hypertension
Orthostatic hypotension
Hypertensive emergency (malignant hypertension) (Correct answer)
White coat hypertension

Correct answer: Hypertensive emergency (malignant hypertension)

Severe hypertension with acute end-organ damage such as papilloedema is a hypertensive emergency.

Question 85: What does a rising serum lactate in a postoperative patient most strongly suggest?

Adequate oxygen delivery
Normal recovery
Tissue hypoperfusion (Correct answer)
Hypothermia alone

Correct answer: Tissue hypoperfusion

Elevated lactate reflects anaerobic metabolism from tissue hypoperfusion and warrants resuscitation review.

Question 86: Bronchioles are the finest branches of the bronchial intercom.

B) True
A) False (Correct answer)

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 87: A patient with chronic kidney disease stage 4 develops fatigue and a haemoglobin of 88 g/L with normal iron stores. What is the primary cause of this anaemia?

Reduced erythropoietin production (Correct answer)
Folate deficiency
Iron deficiency
Haemolysis

Correct answer: Reduced erythropoietin production

Failing kidneys produce insufficient erythropoietin, causing a normocytic normochromic anaemia.

Question 88: 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?

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

Correct answer: Common peroneal (fibular) nerve

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

Question 89: During a surgical procedure, a swab is inadvertently left inside a patient's abdomen. The error is discovered on a post-operative X-ray the next day, and the patient requires a second procedure for its removal. The patient makes a full recovery. According to the Australian Open Disclosure Framework, which of the following is an essential and early component of the open disclosure process with the patient?

An apology or expression of regret for the harm that occurred. (Correct answer)
A detailed explanation of the root cause analysis findings.
Assurance that the hospital's legal team accepts full liability.
Providing the patient with the names of all staff involved in the initial surgery.

Correct answer: An apology or expression of regret for the harm that occurred.

The Australian Open Disclosure Framework is a nationally consistent approach to communicating with patients after an adverse event. A core principle is an early and sincere apology or expression of regret (e.g., "we are sorry") for the harm suffered by the patient. This should be done alongside a factual explanation of what happened. While a root cause analysis is important for systems improvement, its detailed findings come later. Disclosing staff names may not be appropriate, and discussions of legal liability are separate from the initial open disclosure process.

Question 90: A 45-year-old man with a family history of renal failure has flank pain, hypertension, haematuria and bilateral enlarged kidneys with multiple cysts. What is the most likely diagnosis?

Simple renal cysts
Medullary sponge kidney
Autosomal dominant polycystic kidney disease (Correct answer)
Acquired cystic disease

Correct answer: Autosomal dominant polycystic kidney disease

Bilaterally enlarged cystic kidneys with a positive family history indicate autosomal dominant polycystic kidney disease.

Question 91: A patient on an ACE inhibitor develops a persistent dry cough. What is the most appropriate substitute?

Thiazide diuretic
Angiotensin receptor blocker (Correct answer)
Calcium channel blocker
Beta-blocker

Correct answer: Angiotensin receptor blocker

An ARB provides similar benefit without the bradykinin-mediated cough of ACE inhibitors.

Question 92: 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?

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

Correct answer: Superficial incisional SSI

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

Question 93: A 65-year-old man with a history of chronic kidney disease (eGFR 40 mL/min/1.73m²) and peptic ulcer disease presents with an acutely painful, swollen, and red left great toe. Arthrocentesis confirms the presence of negatively birefringent, needle-shaped crystals. What is the most appropriate first-line treatment for his acute gout flare?

Allopurinol
Prednisolone (Correct answer)
Colchicine
Indomethacin

Correct answer: Prednisolone

In a patient with an acute gout flare, the primary goal is to manage pain and inflammation. NSAIDs like indomethacin are contraindicated due to the patient's chronic kidney disease and history of peptic ulcer disease. Allopurinol is a urate-lowering therapy used for long-term prevention and should not be initiated during an acute flare as it can prolong the attack. While colchicine can be used, it requires dose adjustment in renal impairment and has a narrow therapeutic window with potential for significant gastrointestinal side effects. Therefore, oral corticosteroids such as prednisolone are the safest and most appropriate first-line choice in this clinical scenario.

Question 94: A 40-year-old woman presents with fatigue, constipation, dry skin, and cold intolerance. Her TSH is elevated and free T4 is low. What is the diagnosis?

Sick euthyroid syndrome
Primary hypothyroidism (Correct answer)
Secondary hypothyroidism
Subclinical hyperthyroidism

Correct answer: Primary hypothyroidism

A high TSH with low free T4 indicates primary hypothyroidism.

Question 95: A patient asks you not to document their HIV status in shared records. What is the most appropriate response?

Document it in a separate secret file
Explain the clinical and safety importance of accurate records while discussing privacy protections (Correct answer)
Refuse to treat unless they agree
Omit it entirely as requested

Correct answer: Explain the clinical and safety importance of accurate records while discussing privacy protections

Accurate records are essential for safe care, but you should explain confidentiality safeguards rather than falsify records.

Question 96: Which of the following does not belong to the respiratory system's conducting portion?

Bronchioles
Alveoli (Correct answer)
Pharynx
Nose

Correct answer: Alveoli

The conducting portion of the respiratory system includes structures like the nose, pharynx, and bronchioles, which function to transport, warm, humidify, and filter air. The alveoli, however, are part of the *respiratory portion*, where the actual exchange of gases (oxygen and carbon dioxide) between air and blood takes place.

Question 97: A 16-year-old requests contraception and refuses to involve her parents. Under Australian law, what principle determines whether you can prescribe?

Gillick competence / mature minor assessment of her understanding (Correct answer)
Parental consent is always mandatory under 18
Court approval is required for all minors
You must refuse until she turns 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 98: An interpreter is needed for a non-English-speaking patient consenting to surgery. Using the patient's young child to translate is inappropriate because:

Children translate too slowly
It is acceptable if the child is over 10
Interpreters are only needed for written consent
It risks inaccurate translation and breaches confidentiality; a professional interpreter is required (Correct answer)

Correct answer: It risks inaccurate translation and breaches confidentiality; a professional interpreter is required

Family members, especially children, may translate inaccurately and compromise privacy, so a professional interpreter is required.

Question 99: Which test is most sensitive for the diagnosis of active tuberculosis in a sputum sample?

Mycobacterial culture (Correct answer)
Ziehl-Neelsen stain
Tuberculin skin test (Mantoux)
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 100: A 70-year-old man has a resting tremor, bradykinesia and cogwheel rigidity that began on one side. What is the most likely diagnosis?

Cerebellar tremor
Benign physiological tremor
Essential 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 101: A 32-year-old has a positive 75g OGTT at 26 weeks. What is the most appropriate initial management?

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

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 102: What is the recommended timing for routine anti-D prophylaxis in a rhesus-negative pregnant woman without sensitising events?

At around 28 weeks (and at 34 weeks if two-dose regimen) (Correct answer)
Weekly from 20 weeks
Only at delivery
At 12 weeks only

Correct answer: At around 28 weeks (and at 34 weeks if two-dose regimen)

Routine antenatal anti-D prophylaxis is given at around 28 weeks (with a second dose at 34 weeks in two-dose regimens).

Question 103: A patient with gallstones develops fever, jaundice, and right upper quadrant pain (Charcot's triad). What is the diagnosis?

Ascending cholangitis (Correct answer)
Hepatic abscess
Acute cholecystitis
Pancreatitis

Correct answer: Ascending cholangitis

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

Question 104: Berkson's bias is a type of selection bias that classically arises in studies based on:

National census data
Random community samples
Whole-of-population registries
Hospitalised patients (Correct answer)

Correct answer: Hospitalised patients

Berkson's bias occurs when using hospital controls, distorting associations because hospitalisation depends on multiple conditions.

Question 105: Which contraceptive method is most appropriate for a breastfeeding woman 4 weeks postpartum?

Combined vaginal ring
High-dose oestrogen patch
Progestogen-only pill or implant (Correct answer)
Combined oral contraceptive pill

Correct answer: Progestogen-only pill or implant

Progestogen-only methods are preferred in breastfeeding as oestrogen may reduce milk supply and increase VTE risk.

Question 106: What is the first-line treatment for moderate croup?

Oral amoxicillin
Oral or nebulised corticosteroid (dexamethasone) (Correct answer)
Nebulised salbutamol
Immediate intubation

Correct answer: Oral or nebulised corticosteroid (dexamethasone)

A single dose of corticosteroid such as dexamethasone is first-line for croup of any severity.

Question 107: 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.
There should be an accepted and available treatment for the condition if detected. (Correct answer)
The natural history of the condition does not need to be well understood.
The condition must have a very high prevalence in the population.

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 108: A patient presents with a tender, irreducible inguinal hernia with overlying erythema and vomiting. What is the immediate concern?

Lipoma
Hydrocele
Reducible hernia
Strangulation (Correct answer)

Correct answer: Strangulation

An irreducible, tender hernia with systemic signs suggests strangulation requiring urgent surgery.

Question 109: A child with generalised oedema, heavy proteinuria, hypoalbuminaemia and normal blood pressure most likely has which condition?

Heart failure
Acute pyelonephritis
Minimal change nephrotic syndrome (Correct answer)
Acute glomerulonephritis

Correct answer: Minimal change nephrotic syndrome

Massive proteinuria with hypoalbuminaemia and oedema in a young child is typical of minimal change nephrotic syndrome.

Question 110: Which finding is most characteristic of severe pre-eclampsia rather than gestational hypertension?

Proteinuria with epigastric pain and visual disturbance (Correct answer)
BP 130/85 mmHg at term
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 111: When a doctor conscientiously objects to a procedure such as termination of pregnancy, they must still:

Report the patient to authorities
Inform the patient and refer them to another practitioner who can assist, in a timely manner (Correct answer)
Persuade the patient against it
Refuse and provide no further help

Correct answer: Inform the patient and refer them to another practitioner who can assist, in a timely manner

Conscientious objection requires the doctor to disclose the objection and facilitate timely access to another provider.

Question 112: In the WHO surgical safety checklist, when is the 'time out' performed?

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

Correct answer: Before skin incision

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

Question 113: A 32-year-old woman at 34 weeks' gestation presents with a persistent headache and visual disturbances. Her booking blood pressure was 110/70 mmHg. Today, her blood pressure is 150/95 mmHg. A urine dipstick shows 2+ proteinuria. According to the Society of Obstetric Medicine of Australia and New Zealand (SOMANZ) guidelines, which of the following is the most likely diagnosis?

Chronic hypertension
Gestational hypertension
Eclampsia
Pre-eclampsia (Correct answer)

Correct answer: Pre-eclampsia

The patient meets the diagnostic criteria for pre-eclampsia, which is defined as new-onset hypertension (≥140/90 mmHg) after 20 weeks' gestation accompanied by evidence of maternal organ dysfunction or uteroplacental dysfunction. In this case, she has new-onset hypertension plus proteinuria and neurological symptoms (headache, visual disturbances). Gestational hypertension is high blood pressure without proteinuria or other signs of organ dysfunction. Chronic hypertension would have been present before 20 weeks. Eclampsia involves the development of seizures in a woman with pre-eclampsia.

Question 114: A 40-year-old woman reports two weeks of persistent low mood, anhedonia, early morning waking, poor appetite and thoughts that life is not worth living. What is the most appropriate first action?

Refer for dietary advice
Prescribe a hypnotic and review in a month
Recommend increased exercise only
Assess suicide risk in detail (Correct answer)

Correct answer: Assess suicide risk in detail

Any disclosure of thoughts that life is not worth living mandates a detailed suicide risk assessment.

Question 115: Deficiency of which complement protein predisposes to recurrent Neisseria infections?

C1q
C3
C4b
C5–C9 (terminal complement) (Correct answer)

Correct answer: C5–C9 (terminal complement)

Deficiency of terminal complement components (C5–C9, the membrane attack complex) impairs killing of Neisseria species, predisposing to recurrent meningococcal and gonococcal infections.

Question 116: When obtaining valid informed consent for surgery, which element is NOT required?

Disclosure of material risks
A guarantee of a successful outcome (Correct answer)
Voluntariness free from coercion
The patient having capacity

Correct answer: A guarantee of a successful outcome

Consent requires capacity, adequate information, and voluntariness, but no doctor can guarantee outcomes.

Question 117: A junior doctor is asked by a senior to perform a procedure beyond their competence. What should they do?

Refuse and refuse to discuss it further
Perform it to avoid conflict
Decline and seek appropriate supervision or escalate, prioritising patient safety (Correct answer)
Attempt it and hope for the best

Correct answer: Decline and seek appropriate supervision or escalate, prioritising patient safety

Practising within one's competence and seeking supervision protects patient safety.

Question 118: A teenager presents with a circular, scaly lesion with central clearing and a raised advancing border. What is the most likely diagnosis?

Discoid eczema
Psoriasis
Tinea corporis (Correct answer)
Granuloma annulare

Correct answer: Tinea corporis

An annular lesion with central clearing and a scaly active edge is classic for tinea corporis (ringworm).

Question 119: A 30-year-old woman presents with weight loss, heat intolerance, palpitations, and a fine tremor. Which finding most strongly suggests Graves disease specifically?

Tachycardia
Weight loss
Exophthalmos (Correct answer)
Warm peripheries

Correct answer: Exophthalmos

Exophthalmos (thyroid eye disease) is specific to Graves disease among causes of hyperthyroidism.

Question 120: A patient bleeding massively receives a balanced transfusion. What ratio of products is commonly recommended?

4:1:0 red cells to plasma
Platelets alone
1:1:1 red cells, plasma and platelets (Correct answer)
Crystalloid only

Correct answer: 1:1:1 red cells, plasma and platelets

Massive transfusion protocols favour a balanced 1:1:1 ratio to prevent dilutional coagulopathy.

Question 121: 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?

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

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 122: 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 123: A 50-year-old man has sudden onset of a painful, swollen, red first metatarsophalangeal joint. Joint aspiration shows negatively birefringent needle-shaped crystals. What is the diagnosis?

Septic arthritis
Pseudogout
Rheumatoid arthritis
Gout (Correct answer)

Correct answer: Gout

Negatively birefringent needle-shaped crystals confirm monosodium urate deposition, i.e. gout.

Question 124: A patient has signs of malignant hyperthermia under general anaesthesia. What is the specific treatment?

Adrenaline
Dantrolene (Correct answer)
Atropine
Naloxone

Correct answer: Dantrolene

Dantrolene is the specific antidote for malignant hyperthermia, alongside stopping triggers and active cooling.

Question 125: ____________ are the carriers of oxygen.

Monocytes
Platelets
Leucocytes
Erythrocytes (Correct answer)

Correct answer: Erythrocytes

Erythrocytes, or red blood cells, are the primary carriers of oxygen in the blood. They contain hemoglobin, a protein that reversibly binds to oxygen in the lungs and releases it in tissues where oxygen levels are lower, facilitating oxygen transport throughout the body.

Question 126: A 60-year-old smoker presents with weight loss, haemoptysis and a hilar mass on chest X-ray. What is the most important next investigation?

CT chest and bronchoscopy with biopsy (Correct answer)
Repeat chest X-ray in 6 weeks
Spirometry only
Reassurance and smoking cessation advice alone

Correct answer: CT chest and bronchoscopy with biopsy

A suspected lung malignancy requires CT staging and bronchoscopy with biopsy for tissue diagnosis.

Question 127: In a stable population of 50,000 people, there were 1,000 existing cases of diagnosed osteoarthritis at the start of a year. Over the course of that year, 200 new cases were diagnosed. What was the incidence rate of osteoarthritis per 1,000 people for that year?

24.0
4.1 (Correct answer)
5.0
4.0

Correct answer: 4.1

Incidence measures the rate of new cases in the population at risk. The population at risk is the total population minus those who already have the disease (50,000 - 1,000 = 49,000). The calculation is (Number of new cases / Population at risk) * 1000. Therefore, (200 / 49,000) * 1000 ≈ 4.08, which is approximately 4.1 per 1,000 people.

Question 128: 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
Serum C-reactive protein (CRP) and Erythrocyte Sedimentation Rate (ESR)
Blood cultures
Synovial fluid analysis and culture (Correct answer)

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 129: A 30-year-old man with type 1 diabetes reports early morning sweating and headaches, with a fasting hyperglycaemia. Overnight readings show hypoglycaemia at 3am. What does this pattern describe?

Somogyi phenomenon (Correct answer)
Insulin resistance
Honeymoon period
Dawn phenomenon

Correct answer: Somogyi phenomenon

Nocturnal hypoglycaemia triggering counter-regulatory rebound morning hyperglycaemia describes the Somogyi effect.

Question 130: A child presents with a salmon-pink, erythematous rash, high spiking fevers and arthritis. Which condition is most likely?

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

Correct answer: Systemic juvenile idiopathic arthritis

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

Question 131: What is the recommended management of a confirmed term breech presentation in an otherwise uncomplicated pregnancy?

Immediate caesarean at diagnosis
Routine forceps delivery
Await spontaneous version at term
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 132: A 29-year-old woman presents with a history of recurrent headaches. She describes them as a severe, unilateral, pulsating pain that lasts for about 8-10 hours. During the headaches, she feels nauseous and prefers to lie down in a dark, quiet room. She denies any preceding visual disturbances. Based on the International Classification of Headache Disorders (ICHD-3) criteria, what is the most likely diagnosis?

Tension-type headache
Migraine with typical aura
Cluster headache
Migraine without aura (Correct answer)

Correct answer: Migraine without aura

The patient's symptoms align perfectly with the ICHD-3 diagnostic criteria for Migraine without aura. These criteria include a duration of 4-72 hours, unilateral location, pulsating quality, moderate or severe intensity, and associated symptoms like nausea and/or photophobia/phonophobia. She specifically denies aura (like visual disturbances), making 'Migraine with aura' incorrect. Tension-type headaches are typically bilateral and non-pulsating, while cluster headaches are extremely severe, shorter in duration, and associated with autonomic symptoms.

Question 133: A 30-year-old presents with ascending paralysis 2 weeks after a diarrheal illness caused by Campylobacter jejuni. Nerve conduction studies show demyelination. What is the diagnosis?

Guillain-Barré syndrome (Correct answer)
Transverse myelitis
Botulism
Multiple sclerosis

Correct answer: Guillain-Barré syndrome

Guillain-Barré syndrome is an autoimmune demyelinating polyneuropathy classically triggered by Campylobacter jejuni infection.

Question 134: In Bradford Hill's criteria for causation, a dose-response relationship refers to:

Biological plausibility
Greater exposure producing greater risk (Correct answer)
Consistency across studies
Temporal sequence of exposure

Correct answer: Greater exposure producing greater risk

A biological gradient or dose-response means increasing exposure is associated with increasing disease risk.

Question 135: 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)
2 percentage points
80 percentage points
20 percentage points

Correct answer: 8 percentage points

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

Question 136: Which of the following is a notifiable disease that doctors in Australia are legally required to report to public health authorities?

Tuberculosis (Correct answer)
Osteoarthritis
Essential hypertension
Type 2 diabetes

Correct answer: Tuberculosis

Tuberculosis is a nationally notifiable communicable disease requiring mandatory reporting.

Question 137: Which measure quantifies the proportion of disease in exposed individuals attributable to the exposure?

Prevalence ratio
Incidence density
Standardised mortality ratio
Attributable risk (risk difference) (Correct answer)

Correct answer: Attributable risk (risk difference)

Attributable risk is the difference in risk between exposed and unexposed groups, reflecting excess risk due to exposure.

Question 138: 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
Complement consumption via immune complex deposition (Correct answer)
Mast cell degranulation
Natural killer cell activation

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 139: When CO2 levels in the blood increase, breathing becomes ____________

faster and deeper (Correct answer)
slow and deep
no effect on breathing
shallower and deeper

Correct answer: faster and deeper

When carbon dioxide levels in the blood increase, the blood becomes more acidic, which is detected by chemoreceptors. These receptors signal the respiratory centers in the brain to increase both the rate and depth of breathing. This response helps to expel excess CO2 from the body and restore normal blood pH.

Question 140: 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?

Polymyalgia rheumatica (Correct answer)
Polymyositis
Fibromyalgia
Osteoarthritis

Correct answer: Polymyalgia rheumatica

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

Question 141: A 55-year-old man has a clinic blood pressure of 165/100 mmHg on three separate occasions. According to standard guidelines, what is the first-line lifestyle and pharmacological approach for stage 2 hypertension?

No treatment until end-organ damage occurs
Lifestyle modification alone for 12 months
Immediate intravenous antihypertensives
Lifestyle modification plus antihypertensive medication (Correct answer)

Correct answer: Lifestyle modification plus antihypertensive medication

Stage 2 hypertension warrants both lifestyle changes and pharmacotherapy.

Question 142: A 62-year-old woman, G2P2, who went through menopause 10 years ago, presents with a single episode of vaginal spotting. She is not on hormone replacement therapy and has a BMI of 32 kg/m². What is the most appropriate initial investigation to assess her risk of endometrial carcinoma?

Diagnostic hysteroscopy with endometrial biopsy
Transvaginal ultrasound to measure endometrial thickness (Correct answer)
Cervical HPV test
Serum CA-125 measurement

Correct answer: Transvaginal ultrasound to measure endometrial thickness

Postmenopausal bleeding (PMB) is a red flag for endometrial cancer, which must be excluded. A transvaginal ultrasound is the recommended initial investigation to measure endometrial thickness (ET). An ET of less than or equal to 4-5mm has a very high negative predictive value for endometrial cancer. If the endometrium is thickened, further investigation with an endometrial biopsy is warranted. While a cervical screening test is important, it doesn't assess the endometrium. Direct biopsy is usually a second-line investigation after imaging, and CA-125 is not a screening tool for endometrial cancer.

Question 143: Which antibiotic class is first-line for treating pertussis?

Macrolides (e.g. azithromycin) (Correct answer)
Penicillins
Aminoglycosides
Cephalosporins

Correct answer: Macrolides (e.g. azithromycin)

Macrolides such as azithromycin are first-line for pertussis and reduce transmissibility.

Question 144: A 35-year-old presents with recurrent anterior epistaxis originating from the Kiesselbach plexus (Little's area). The bleeding is moderate and the patient is haemodynamically stable. What is the correct initial management?

Urgent sphenopalatine artery ligation
Posterior nasal packing
Firm pinching of the soft part of the nose for 10-15 minutes while leaning forward (Correct answer)
Immediate anterior nasal packing with ribbon gauze

Correct answer: Firm pinching of the soft part of the nose for 10-15 minutes while leaning forward

First-line management of anterior epistaxis is direct pressure by pinching the soft cartilaginous part of the nose for 10-15 minutes while the patient leans forward; this compresses the Kiesselbach plexus effectively.

Question 145: A child with a sandpaper-like rash, strawberry tongue, fever and a recent streptococcal pharyngitis most likely has which condition?

Scarlet fever (Correct answer)
Kawasaki disease
Measles
Roseola

Correct answer: Scarlet fever

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

Question 146: An 82-year-old man with metastatic lung cancer and a valid Advance Care Directive (ACD) is admitted with sepsis from a urinary tract infection. The ACD clearly states he refuses all life-sustaining treatments, including intravenous antibiotics and admission to an intensive care unit. The patient is now delirious and lacks decision-making capacity. His family is adamant that he should receive antibiotics, stating, "He wouldn't want to die from a simple infection." What is the most appropriate and legally defensible course of action for the treating doctor?

Seek an urgent ethics committee review before making a decision.
Provide palliative care but administer antibiotics for comfort.
Uphold the patient's refusal of treatment as stated in the valid ACD. (Correct answer)
Follow the family's wishes and commence intravenous antibiotics.

Correct answer: Uphold the patient's refusal of treatment as stated in the valid ACD.

In Australia, a valid and specific Advance Care Directive (ACD) is a legally binding document that represents the patient's wishes. When a patient loses decision-making capacity, the instructions in the ACD must be followed, even if they conflict with the wishes of the family or the treating team's clinical judgment about what might be 'best'. The refusal of IV antibiotics is a specific instruction for a life-sustaining treatment, which must be respected. Seeking an ethics review is a good step in complex cases but does not override the legal standing of the ACD. Administering antibiotics against a valid refusal would constitute medical battery.

Question 147: A 28-year-old primigravida attends her first antenatal visit at 10 weeks' gestation. She is interested in screening for fetal chromosomal abnormalities like Down syndrome. According to Australian guidelines, which of the following is the most commonly offered and recommended initial screening test?

Fetal morphology ultrasound at 20 weeks
Amniocentesis at 16 weeks
Maternal serum alpha-fetoprotein (MSAFP) alone
Combined first-trimester screening (nuchal translucency ultrasound and maternal serum markers) (Correct answer)

Correct answer: Combined first-trimester screening (nuchal translucency ultrasound and maternal serum markers)

Combined first-trimester screening (cFTS) is the standard initial screening test for chromosomal abnormalities offered in Australia. It combines a maternal blood test (measuring PAPP-A and free β-hCG) between 9 and 13 weeks with a nuchal translucency (NT) ultrasound scan between 11 and 13 weeks. This combination provides a risk assessment for conditions like Down syndrome (Trisomy 21) and Edwards syndrome (Trisomy 18). Amniocentesis is a diagnostic test, not a screening test, and is offered if screening indicates a high risk. MSAFP alone is part of second-trimester screening, which is less accurate than cFTS. The 20-week morphology scan can detect structural anomalies but is not the primary screening tool for chromosomal aneuploidy.

Question 148: A diabetic patient has a HbA1c of 9.5% before elective hernia repair. What is the best action?

Double the insulin only on the operative morning
Proceed immediately regardless
Cancel surgery permanently
Defer surgery to optimise glycaemic control (Correct answer)

Correct answer: Defer surgery to optimise glycaemic control

Poor glycaemic control raises infection and wound risk, so elective surgery should be deferred for optimisation.

Question 149: Which of these is an absolute indication for blood transfusion intraoperatively?

Haemoglobin of 110 g/L in a stable patient
Symptomatic anaemia with ongoing haemorrhage and hypoxia (Correct answer)
Patient anxiety
Routine for all major operations

Correct answer: Symptomatic anaemia with ongoing haemorrhage and hypoxia

Transfusion is indicated for symptomatic anaemia with active bleeding and inadequate oxygen delivery.

Question 150: An elderly man develops fluctuating cognition, recurrent visual hallucinations and spontaneous parkinsonism. What is the most likely diagnosis?

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

Correct answer: Lewy body dementia

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

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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