HKMLE Part I

A patient presents 10 hours after ingesting a large amount of paracetamol. Which mechanism best explains why N-acetylcysteine is given?

• AIt replenishes glutathione to detoxify NAPQI
• BIt blocks cyclooxygenase-mediated renal vasoconstriction
• CIt chelates salicylate and increases urinary excretion
• DIt reverses opioid receptor agonism in the brainstem

A man has shoulder trauma with weakness abducting the arm from 15 to 90 degrees and numbness over the lateral deltoid area. Which nerve is most likely injured?

• AAxillary nerve
• BRadial nerve
• CSuprascapular nerve
• DLong thoracic nerve

Spirometry in a wheezy patient shows reduced FEV1/FVC that improves significantly after salbutamol. Which interpretation is most appropriate?

• AReversible obstructive ventilatory defect
• BFixed restrictive ventilatory defect
• CNormal spirometry with poor effort only
• DIsolated diffusion impairment

A man with known G6PD deficiency develops jaundice and dark urine after taking an oxidant drug. Blood film shows bite cells. What is the main pathophysiology?

• AImpaired NADPH production causing oxidative red-cell damage
• BDefective alpha-globin chain synthesis
• CAutoantibody-mediated warm haemolysis
• DMechanical shearing across a prosthetic valve

Which antimicrobial mechanism is correctly matched with the drug?

• AVancomycin binds D-Ala-D-Ala and inhibits cell-wall synthesis
• BAminoglycosides inhibit folate synthesis
• CMacrolides block bacterial DNA gyrase
• DBeta-lactams inhibit the 50S ribosomal subunit

A patient with nephrotic syndrome has ankle oedema, heavy proteinuria, low serum albumin and hyperlipidaemia. Which mechanism best explains the oedema?

• ALoss of plasma oncotic pressure from urinary albumin loss
• BIncreased albumin production by the liver
• CReduced capillary hydrostatic pressure
• DPrimary lymphatic obstruction of both legs

An elderly patient with chronic kidney disease is prescribed gentamicin for severe Gram-negative sepsis. Which prescribing principle is most important?

• AAdjust dosing and monitor levels because aminoglycosides are renally cleared
• BAvoid all drug-level monitoring because peak levels are unreliable
• CGive a fixed adult dose because aminoglycosides are hepatically metabolised
• DCombine with another nephrotoxin to prevent resistance

A patient develops fever, flank pain, hypotension and haemoglobinuria shortly after a blood transfusion is started. What is the immediate action?

• AStop the transfusion and maintain IV access with normal saline
• BSlow the transfusion and prescribe an antihistamine
• CContinue the transfusion with furosemide cover
• DRestart the same unit after symptoms settle

A 58-year-old man presents 45 minutes after crushing central chest pain. ECG shows ST elevation in II, III and aVF. What is the best immediate reperfusion strategy if available promptly?

• APrimary percutaneous coronary intervention
• BOutpatient treadmill testing
• CElective coronary CT in 6 weeks
• DHigh-dose oral nitrate therapy alone

A 76-year-old woman with hypertension and diabetes has persistent non-valvular atrial fibrillation. What is the main reason to offer long-term oral anticoagulation if there is no contraindication?

• ATo reduce cardioembolic stroke risk
• BTo convert atrial fibrillation to sinus rhythm
• CTo prevent infective endocarditis
• DTo treat symptomatic bradycardia

A patient with known heart failure presents with acute pulmonary oedema, severe dyspnoea and bibasal crepitations. Which initial treatment combination is most appropriate?

• AOxygen if hypoxaemic, nitrates if blood pressure allows, and IV furosemide
• BLarge-volume IV saline and beta-blocker loading
• COral antibiotics alone and discharge
• DImmediate thrombolysis without ECG

A 62-year-old man has abrupt tearing chest pain radiating to the back and unequal arm blood pressures. Which investigation is most appropriate if he is haemodynamically stable?

• ACT angiography of the aorta
• BExercise stress ECG
• CBarium swallow
• DRoutine outpatient echocardiogram only

A young adult with type 1 diabetes has vomiting, dehydration, glucose 28 mmol/L, ketones and metabolic acidosis. Potassium is 2.9 mmol/L. What should be corrected before starting insulin?

• AHypokalaemia
• BMild hyperglycaemia
• CLow serum amylase
• DRespiratory alkalosis

A woman with Graves disease has fever, agitation, diarrhoea, heart rate 160/min and heart failure. Which treatment sequence is most appropriate after resuscitation?

• ABeta-blocker, thionamide, iodine after thionamide, and corticosteroid
• BIodine first, then no antithyroid drug
• CLevothyroxine and observation
• DRadioiodine ablation as the immediate emergency treatment

A cirrhotic patient presents with haematemesis and hypotension. After airway assessment and IV access, which drug strategy should be started early while arranging urgent endoscopy?

• AVasoactive therapy plus prophylactic antibiotics
• BHigh-dose aspirin and clopidogrel
• COral iron only
• DWarfarin loading

A patient with acute epigastric pain radiating to the back has lipase more than three times the upper limit of normal. What is the most important early management?

• AIV fluid resuscitation, analgesia and assessment for gallstones or alcohol
• BImmediate long-term pancreatic enzyme replacement
• CRoutine prophylactic antibiotics for all cases
• DEmergency total pancreatectomy

A patient has fever, right upper quadrant pain, jaundice, confusion and hypotension. Ultrasound shows a dilated common bile duct. What is the definitive source-control step?

• AUrgent biliary decompression, usually by ERCP
• BElective outpatient cholecystectomy in 3 months
• CColonoscopy
• DHigh-dose proton pump inhibitor alone

A cirrhotic patient with ascites has abdominal pain and fever. Diagnostic tap shows ascitic neutrophils 420 cells/mm3. What is the next step?

• ATreat spontaneous bacterial peritonitis with appropriate antibiotics
• BWait for culture results before any treatment
• CGive high-dose diuretics only
• DPerform routine therapeutic anticoagulation

A 68-year-old man has iron-deficiency anaemia with low ferritin and no obvious dietary cause. What investigation strategy is most appropriate?

• AEvaluate for gastrointestinal blood loss, including endoscopic assessment
• BReassure without follow-up because anaemia is normal with age
• CTreat with folate only
• DDiagnose thalassaemia trait without further tests

A patient has fever, confusion, thrombocytopenia, microangiopathic haemolytic anaemia with schistocytes, and renal impairment. Which urgent treatment is indicated?

• APlasma exchange for thrombotic thrombocytopenic purpura
• BPlatelet transfusion as routine first-line treatment
• CLong-term oral iron only
• DSplenectomy before stabilisation

An older man with urinary retention has rising creatinine and bilateral hydronephrosis on ultrasound. What is the likely category of acute kidney injury?

• APost-renal obstruction
• BPre-renal hypovolaemia
• CIntrinsic glomerulonephritis
• DDrug-induced interstitial nephritis only

A patient with chronic kidney disease has potassium 7.0 mmol/L and peaked T waves. Which treatment should be given first to reduce immediate arrhythmia risk?

• AIV calcium gluconate
• BOral calcium carbonate
• CLoop diuretic in 24 hours
• DDietary potassium advice only

A 64-year-old presents 90 minutes after sudden aphasia and right arm weakness. What is the immediate imaging priority before thrombolysis is considered?

• AUrgent non-contrast CT brain to exclude haemorrhage
• BMRI spine
• CCarotid ultrasound as the only initial test
• DNo imaging because the history is diagnostic

A patient with myasthenia gravis develops pneumonia, bulbar weakness and shallow breathing. Which management issue is most urgent?

• AAssess respiratory function and prepare ventilatory support if needed
• BGive a high-dose beta-blocker
• CDelay treatment until acetylcholine receptor antibody returns
• DPrescribe magnesium for muscle strength

A patient with COPD exacerbation has oxygen saturation 82% on air and is drowsy with raised PaCO2. What oxygen strategy is safest initially?

• AControlled oxygen targeting saturation 88-92%
• BHigh-flow oxygen targeting 100% saturation indefinitely
• CNo oxygen because CO2 is raised
• DOnly oral bronchodilator without monitoring

A man has cough, weight loss, night sweats and upper-lobe cavitation on chest X-ray. In Hong Kong clinical practice, what should be done while diagnostic sputum tests are arranged?

• AUse airborne precautions and notify suspected tuberculosis through the appropriate public…
• BDischarge without follow-up because cavitation is benign
• CStart long-term steroids before microbiology
• DGive oseltamivir only

A woman with SLE has rising creatinine, hypertension, haematuria and proteinuria. Which investigation best guides classification and immunosuppressive treatment?

• ARenal biopsy
• BPlain abdominal X-ray
• CPeak expiratory flow rate
• DRandom cortisol only

A patient develops urticaria, wheeze and hypotension minutes after an injection. What is the first-line drug and route?

• AIntramuscular adrenaline into the lateral thigh
• BOral cetirizine alone
• CNebulised salbutamol as the only treatment
• DIV furosemide

A traveller returns to Hong Kong with high fever, severe myalgia, thrombocytopenia and a positive dengue NS1 antigen. He has abdominal pain and mucosal bleeding. What is the safest management?

• AAdmit or closely monitor for severe dengue and avoid NSAIDs
• BPrescribe aspirin for pain and send home without warning advice
• CStart high-dose heparin
• DGive routine corticosteroids to all dengue patients

A junior doctor sustains a needlestick injury from a patient later found to have untreated HIV. What is the key principle for HIV post-exposure prophylaxis?

• AStart PEP as soon as possible, ideally within hours and not beyond 72 hours
• BWait 6 weeks for seroconversion before starting treatment
• CGive one dose of hepatitis B vaccine only and no HIV assessment
• DUse PEP only if symptoms of acute HIV develop

An 82-year-old inpatient becomes acutely inattentive, fluctuates between agitation and drowsiness, and has a urinary infection. Which diagnosis best fits?

• ADelirium
• BAlzheimer disease alone
• CGeneralised anxiety disorder
• DStable personality disorder

An elderly patient with CKD and recurrent hypoglycaemia is taking a long-acting sulfonylurea. What prescribing response is most appropriate?

• AReview and de-intensify hypoglycaemic therapy, avoiding high-risk sulfonylurea exposure
• BIncrease the sulfonylurea dose because CKD causes insulin resistance only
• CIgnore hypoglycaemia if HbA1c is low
• DAdd another sulfonylurea from the same class

A hotel worker has severe pneumonia, hyponatraemia, diarrhoea and confusion. Several colleagues have milder febrile respiratory illness. Which organism and investigation are most relevant?

• ALegionella pneumophila; urinary antigen and respiratory culture/PCR
• BMycoplasma pneumoniae; stool ova and parasite test
• CPneumocystis jirovecii; Weil-Felix test
• DClostridioides difficile; sputum acid-fast bacilli only

A young adult has migratory periumbilical pain localising to the right lower quadrant with fever and rebound tenderness. What is the most likely diagnosis?

• AAcute appendicitis
• BUncomplicated gastro-oesophageal reflux
• CTension headache
• DBenign prostatic hyperplasia

A patient with previous laparotomy has colicky abdominal pain, vomiting, distension and no flatus. CT suggests adhesive small bowel obstruction without ischaemia. What initial management is appropriate?

• AIV fluids, nasogastric decompression, analgesia and close surgical observation
• BImmediate colonoscopy as first-line decompression
• CHigh-fibre diet and discharge
• DOral loperamide to stop bowel movement

A man has sudden severe epigastric pain, rigid abdomen and erect chest X-ray showing free subdiaphragmatic air. What is the likely diagnosis and management?

• APerforated viscus; resuscitation, antibiotics and urgent surgery
• BUncomplicated dyspepsia; antacid and discharge
• CRenal colic; oral fluids only
• DViral gastroenteritis; avoid surgical review

A woman has fever, right upper quadrant pain and a positive Murphy sign. Ultrasound shows gallstones and gallbladder wall thickening. What is the diagnosis?

• AAcute cholecystitis
• BAcute appendicitis
• CUlcerative colitis flare
• DUncomplicated renal cyst

A patient with jaundice, fever and shock has a dilated bile duct from a common duct stone. After resuscitation and antibiotics, what is the most important next step?

• AEmergency ERCP for biliary drainage
• BElective outpatient MRI in 6 months
• CAppendicectomy
• DHigh-dose loperamide

An elderly woman has a tender irreducible lump below and lateral to the pubic tubercle with vomiting and abdominal distension. Which diagnosis is most likely?

• AStrangulated femoral hernia
• BReducible indirect inguinal hernia
• CBartholin cyst
• DSaphena varix without obstruction

A 45-year-old woman has a new hard breast lump. Which combination best describes triple assessment?

• AClinical examination, breast imaging and tissue diagnosis
• BCA 15-3, PET scan and reassurance
• CMammography only
• DEmpirical antibiotics without review

A patient has a 2 cm thyroid nodule and suppressed TSH. What is the next investigation before deciding on biopsy?

• ARadionuclide thyroid scan
• BRandom serum amylase
• CColonoscopy
• DAnkle-brachial pressure index

After chest trauma, a patient is hypotensive with severe dyspnoea, distended neck veins, tracheal deviation and absent breath sounds on the left. What should be done first?

• AImmediate decompression of tension pneumothorax
• BWait for CT chest before treatment
• CGive oral antibiotics and observe
• DPerform lumbar puncture

A 72-year-old man has sudden back pain, collapse and a pulsatile abdominal mass. He remains hypotensive despite initial fluids. What is the best next step?

• AImmediate vascular surgery involvement for suspected ruptured abdominal aortic aneurysm
• BRoutine outpatient ultrasound
• CColonoscopy after bowel preparation
• DDischarge when pain improves

A haemodynamically stable patient has fresh rectal bleeding. After resuscitation and risk assessment, which investigation commonly identifies and treats colonic sources?

• AColonoscopy after appropriate bowel preparation
• BPlain skull X-ray
• CSpirometry
• DElectroencephalogram

An elderly patient with atrial fibrillation develops sudden severe abdominal pain out of proportion to examination, metabolic acidosis and raised lactate. Which diagnosis must be treated urgently?

• AAcute mesenteric ischaemia
• BIrritable bowel syndrome
• CUncomplicated haemorrhoids
• DViral pharyngitis

A 16-year-old boy has sudden severe testicular pain, high-riding testis and absent cremasteric reflex. What is the priority?

• AUrgent surgical exploration for testicular torsion
• BWait for outpatient urology appointment
• CTreat as uncomplicated epididymitis only
• DReassure because torsion is painless

A patient with a ureteric stone has fever, rigors, hypotension and hydronephrosis. What is the key management principle?

• AUrgent decompression with stent or nephrostomy plus antibiotics
• BAnalgesia alone until the fever settles
• COral fluids and discharge
• DExtracorporeal shock wave lithotripsy as the only emergency step