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Cambodia Medicine Exit Exam study materials
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Cambodia Medicine Exit Exam practice questions

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Question 1Internal Medicine

A 54-year-old man with type 2 diabetes has an HbA1c of 9.4% after three months of metformin at maximum tolerated dose. He has no history of cardiovascular or kidney disease and his eGFR is 88 mL/min/1.73 m². Which addition to metformin gives the greatest reduction in HbA1c?

  1. Sitagliptin
  2. Pioglitazone
  3. Acarbose
  4. Insulin Correct answer.

Explanation

Insulin has the greatest and most predictable glucose-lowering potency of any agent, typically reducing HbA1c by 1.5–3.5%, which is needed when the HbA1c is far above target. DPP-4 inhibitors, thiazolidinediones and alpha-glucosidase inhibitors each lower HbA1c by roughly 0.5–1.0% and are insufficient for a 9.4% value.

Question 2Internal Medicine

Which finding on physical examination is most characteristic of a tension pneumothorax?

  1. Dullness to percussion with increased tactile fremitus
  2. Fine inspiratory crackles at the lung bases
  3. Hyperresonance with absent breath sounds on the affected side Correct answer.
  4. Tracheal deviation toward the affected side

Explanation

Tension pneumothorax produces a pleural space filled with air under pressure, giving hyperresonance, absent breath sounds and reduced vocal resonance on the affected side. Tracheal deviation occurs away from the affected side and is a late sign, while dullness and increased fremitus indicate consolidation or effusion.

Question 3Internal Medicine

A 28-year-old woman presents with palpitations, heat intolerance, weight loss and a diffuse goitre. Which laboratory pattern is expected in untreated Graves disease?

  1. Low TSH, high free T4, high TSH-receptor antibodies Correct answer.
  2. High TSH, high free T4, normal TSH-receptor antibodies
  3. Low TSH, low free T4, low free T3
  4. High TSH, low free T4, high anti-thyroid peroxidase antibodies

Explanation

Graves disease is caused by TSH-receptor stimulating antibodies, so the thyroid is driven despite suppression of pituitary TSH. The resulting pattern is a suppressed TSH with elevated free T4 and positive TSH-receptor antibodies.

Question 4Internal Medicine

A 62-year-old man has an acute inferior ST-elevation myocardial infarction. Which finding on the ECG should raise concern for right ventricular involvement?

  1. ST elevation in lead V1 with ST depression in lead V2 Correct answer.
  2. ST depression in leads V1–V3 with tall R waves
  3. Peaked T waves in leads V3–V5
  4. ST elevation in lead aVL greater than in lead I

Explanation

Right ventricular infarction commonly accompanies inferior infarction and produces ST elevation in V1, often with ST depression in V2, as the right ventricle is anterior. This finding matters because these patients are preload dependent and may become hypotensive with nitrates.

Question 5Internal Medicine

Which organism is the most common cause of community-acquired pneumonia requiring hospital admission in adults?

  1. Klebsiella pneumoniae
  2. Streptococcus pneumoniae Correct answer.
  3. Mycoplasma pneumoniae
  4. Pneumocystis jirovecii

Explanation

Streptococcus pneumoniae remains the single most frequently identified cause of community-acquired pneumonia in adults, including those admitted to hospital. Mycoplasma is common in younger outpatients, Klebsiella is associated with alcohol use and aspiration, and Pneumocystis occurs in immunocompromised hosts.

Question 6Internal Medicine

A 45-year-old man with a 20-pack-year smoking history has chronic productive cough and an FEV1/FVC ratio of 0.62 after bronchodilator. Which statement about his condition is correct?

  1. Spirometry must be repeated after a two-week course of oral steroids to confirm the diagnosis
  2. The post-bronchodilator FEV1/FVC below 0.70 confirms persistent airflow obstruction Correct answer.
  3. The FEV1/FVC ratio is expected to be above 0.80 in established disease
  4. A normal chest radiograph excludes the diagnosis

Explanation

A post-bronchodilator FEV1/FVC ratio below 0.70 in a patient with compatible symptoms and risk factors establishes the diagnosis of chronic obstructive pulmonary disease. Chest radiography is used to exclude alternative diagnoses, not to confirm or refute airflow obstruction.

Question 7Internal Medicine

A 70-year-old woman with atrial fibrillation has a CHA2DS2-VASc score of 4 and no bleeding risk factors. Which anticoagulation strategy is recommended?

  1. Dual antiplatelet therapy
  2. Oral anticoagulation with a direct oral anticoagulant or warfarin Correct answer.
  3. Aspirin alone
  4. No anticoagulation because she is over 65

Explanation

A CHA2DS2-VASc score of 2 or more in a woman, or 1 or more in a man, is an indication for oral anticoagulation to prevent stroke. A direct oral anticoagulant or dose-adjusted warfarin is appropriate, and antiplatelet therapy is not an adequate substitute.

Question 8Internal Medicine

Which electrolyte abnormality most typically produces a prolonged QT interval with a risk of torsades de pointes?

  1. Hypocalcaemia
  2. Hyperkalaemia
  3. Hypomagnesaemia Correct answer.
  4. Hypernatraemia

Explanation

Hypomagnesaemia prolongs the QT interval and predisposes to torsades de pointes, particularly when combined with hypokalaemia or QT-prolonging drugs. Magnesium replacement is both therapeutic and preventive in this setting.

Question 9Internal Medicine

A 34-year-old man has sudden severe headache described as the worst of his life, neck stiffness and photophobia. Non-contrast CT of the head is normal. What is the next most appropriate step?

  1. Discharge with analgesia and outpatient review
  2. Immediate lumbar puncture without further imaging
  3. MRI of the brain within one week
  4. Lumbar puncture for xanthochromia after at least 12 hours from symptom onset Correct answer.

Explanation

A normal CT does not exclude subarachnoid haemorrhage, especially within the first hours, so lumbar puncture is performed to look for xanthochromia. It should be delayed until at least 12 hours after symptom onset so that bilirubin pigment has formed and can be distinguished from a traumatic tap.

Question 10Internal Medicine

Which clinical feature best distinguishes an ischaemic stroke from a hypoglycaemic episode causing focal neurological deficits?

  1. Presence of hemiparesis
  2. Rapid improvement after glucose administration Correct answer.
  3. History of hypertension
  4. Sudden onset of symptoms

Explanation

Hypoglycaemia can mimic stroke with focal deficits, so a capillary glucose is checked in every suspected stroke. Correction of hypoglycaemia produces rapid clinical improvement, whereas a true ischaemic stroke does not resolve with glucose alone.

Question 11Internal Medicine

A 26-year-old woman has a generalised tonic-clonic seizure, and her blood pressure is 150/95 mmHg with 3+ proteinuria at 36 weeks of gestation. Which treatment is indicated for seizure prophylaxis?

  1. Carbamazepine
  2. Phenytoin
  3. Diazepam infusion
  4. Magnesium sulfate Correct answer.

Explanation

This presentation is pre-eclampsia with eclampsia, and magnesium sulfate is the drug of choice for preventing and treating eclamptic seizures. It is more effective than phenytoin or diazepam and is given with monitoring of deep tendon reflexes and respiratory rate.

Question 12Internal Medicine

Which urinalysis finding is most suggestive of acute glomerulonephritis?

  1. Dysmorphic red blood cells and red cell casts Correct answer.
  2. Uric acid crystals
  3. Broad waxy casts
  4. White cell casts

Explanation

Glomerular inflammation allows red blood cells to pass into the tubules, where they deform and become dysmorphic and form red cell casts. These findings localise the bleeding to the glomerulus and distinguish glomerulonephritis from lower urinary tract bleeding.

Question 13Internal Medicine

A 58-year-old man with nephrotic syndrome has proteinuria of 6 g/day and serum albumin of 22 g/L. Which complication should be anticipated and managed?

  1. Hypercalcaemia
  2. Polycythaemia
  3. Metabolic alkalosis
  4. Hypercoagulability with renal vein thrombosis Correct answer.

Explanation

Loss of antithrombin III and other anticoagulant proteins in the urine creates a hypercoagulable state, and renal vein thrombosis is a classic complication of nephrotic syndrome. Anticoagulation may be considered in high-risk patients with severe hypoalbuminaemia.

Question 14Internal Medicine

A 40-year-old man has a duodenal ulcer and a positive rapid urease test. Which regimen is appropriate for eradication?

  1. Proton pump inhibitor plus two antibiotics for 14 days Correct answer.
  2. Proton pump inhibitor alone for 8 weeks
  3. Antacid plus amoxicillin for 3 days
  4. H2 receptor antagonist alone for 4 weeks

Explanation

Helicobacter pylori eradication requires a proton pump inhibitor combined with at least two antibiotics, commonly amoxicillin plus clarithromycin, for 10–14 days. Acid suppression alone heals the ulcer but does not eradicate the organism, and relapse is common if infection persists.

Question 15Internal Medicine

A 52-year-old woman has right upper quadrant pain, fever and jaundice. Ultrasound shows gallstones and a dilated common bile duct. What is the most likely diagnosis?

  1. Ascending cholangitis Correct answer.
  2. Acute pancreatitis
  3. Hepatitis A infection
  4. Acute cholecystitis

Explanation

The combination of fever, jaundice and right upper quadrant pain with a dilated common bile duct indicates ascending cholangitis from biliary obstruction. It is an emergency requiring antibiotics and biliary drainage, usually by endoscopic retrograde cholangiopancreatography.

Question 16Internal Medicine

Which finding is most characteristic of upper gastrointestinal bleeding from a peptic ulcer?

  1. Painless jaundice
  2. Bright red blood per rectum with normal nasogastric aspirate
  3. Haematemesis with coffee-ground appearance Correct answer.
  4. Steatorrhoea

Explanation

Bleeding from a peptic ulcer usually presents with haematemesis, often coffee-ground in appearance because acid converts haemoglobin. Melena may also occur, but bright red rectal bleeding points more to a lower source.

Question 17Internal Medicine

A 24-year-old woman has a malar rash, arthralgia, oral ulcers and a positive antinuclear antibody test. Which additional test is most specific for systemic lupus erythematosus?

  1. Antineutrophil cytoplasmic antibody
  2. Anti-histone antibody
  3. Anti-double-stranded DNA antibody Correct answer.
  4. Rheumatoid factor

Explanation

Anti-double-stranded DNA antibodies are highly specific for systemic lupus erythematosus and their titre correlates with disease activity, particularly lupus nephritis. Antinuclear antibody is sensitive but not specific and is used mainly as a screening test.

Question 18Internal Medicine

A 66-year-old man has symmetrical small joint pain and swelling of the hands for six months with morning stiffness lasting over an hour. Which finding is most consistent with rheumatoid arthritis?

  1. Marginal erosions on hand radiographs Correct answer.
  2. Asymmetrical involvement of the first metatarsophalangeal joint
  3. Heberden nodes at the distal interphalangeal joints
  4. Tophi over the olecranon bursa

Explanation

Rheumatoid arthritis is an erosive synovitis that classically produces marginal erosions and periarticular osteopenia on radiographs of the hands and feet. Symmetrical small joint involvement with prolonged morning stiffness further supports the diagnosis.

Question 19Internal Medicine

A 30-year-old man has sudden onset of severe testicular pain, nausea and a high-riding testis. Which is the most appropriate immediate step?

  1. Empirical antibiotics for epididymitis
  2. Scrotal support and outpatient review in one week
  3. Ultrasound in two days
  4. Urgent urological assessment for surgical exploration Correct answer.

Explanation

Testicular torsion is a surgical emergency and the testis can be salvaged if detorsion occurs within about six hours. Clinical suspicion should prompt immediate urological consultation and exploration rather than delaying for investigations.

Question 20Internal Medicine

Which abnormality on complete blood count is most typical of iron deficiency anaemia?

  1. Microcytic hypochromic red cells with low ferritin Correct answer.
  2. Normocytic anaemia with high reticulocyte count
  3. Microcytic anaemia with high ferritin and normal transferrin saturation
  4. Macrocytic red cells with high vitamin B12

Explanation

Iron deficiency reduces haemoglobin synthesis, producing small hypochromic red cells, and body iron stores fall so serum ferritin is low. A low ferritin in the setting of anaemia is the most specific indicator of iron deficiency.

Question 21Internal Medicine

A 68-year-old woman has fatigue, macrocytic anaemia and paraesthesiae of the hands and feet. Which underlying mechanism best explains her anaemia?

  1. Bone marrow infiltration by malignancy
  2. Increased red cell destruction from haemolysis
  3. Reduced haemoglobin synthesis from iron deficiency
  4. Impaired DNA synthesis from vitamin B12 deficiency Correct answer.

Explanation

Vitamin B12 deficiency impairs DNA synthesis, causing nuclear-cytoplasmic asynchrony and macrocytic anaemia, and it also causes subacute combined degeneration of the spinal cord. Neurological features such as peripheral paraesthesiae support this diagnosis.

Question 22Internal Medicine

A 72-year-old man has a haemoglobin of 8 g/dL, a raised total protein and a monoclonal band on serum electrophoresis. Which diagnosis should be considered?

  1. Acute lymphoblastic leukaemia
  2. Iron deficiency anaemia
  3. Multiple myeloma Correct answer.
  4. Essential thrombocythaemia

Explanation

Anaemia with a monoclonal paraprotein in an older adult suggests a plasma cell dyscrasia such as multiple myeloma, which should be evaluated with bone marrow examination and skeletal survey. Hypercalcaemia, renal impairment and bone pain are other typical features.

Question 23Internal Medicine

A 60-year-old man is admitted with confusion, fever and a productive cough. His blood pressure is 88/54 mmHg and lactate is 4 mmol/L after 30 mL/kg of crystalloid. Which vasopressor is first-line for septic shock?

  1. Phenylephrine
  2. Dobutamine
  3. Norepinephrine Correct answer.
  4. Dopamine

Explanation

Norepinephrine is the first-line vasopressor for septic shock because it raises mean arterial pressure with less tachycardia and fewer arrhythmias than dopamine. It is started when hypotension persists despite adequate fluid resuscitation.

Question 24Internal Medicine

A 45-year-old man has sudden tearing chest pain radiating to the back with a blood pressure difference of 30 mmHg between arms. Which investigation is most appropriate for a haemodynamically stable patient?

  1. D-dimer measurement alone
  2. CT angiography of the aorta Correct answer.
  3. Transthoracic echocardiography
  4. Exercise stress testing

Explanation

The presentation suggests aortic dissection, and CT angiography of the aorta is the investigation of choice in a stable patient, identifying the intimal flap and extent of dissection. Immediate blood pressure control with a beta-blocker is started while arranging imaging.

Question 25Internal Medicine

A 22-year-old woman has polyuria, polydipsia and a serum sodium of 152 mmol/L with a urine osmolality of 90 mOsm/kg after water deprivation. Which diagnosis is most likely?

  1. Diabetes mellitus
  2. Central diabetes insipidus Correct answer.
  3. Syndrome of inappropriate antidiuretic hormone secretion
  4. Primary polydipsia

Explanation

Hypernatraemia with dilute urine that fails to concentrate after water deprivation indicates a failure of antidiuretic hormone action. Central diabetes insipidus is confirmed by a rise in urine osmolality after desmopressin administration, and nephrogenic causes fail to respond.

Question 26Internal Medicine

A 19-year-old university student in Phnom Penh presents with three days of fever, severe retro-orbital headache, myalgia and a maculopapular rash over the trunk. The tourniquet test is positive and the platelet count is 90 × 10⁹/L with a rising haematocrit. Which diagnosis is most likely?

  1. Scrub typhus
  2. Acute HIV seroconversion
  3. Dengue infection Correct answer.
  4. Leptospirosis

Explanation

Fever with retro-orbital pain, myalgia, a positive tourniquet test, thrombocytopenia and rising haematocrit (suggesting plasma leakage) is the classic picture of dengue, which is endemic in Cambodia and peaks in the rainy season. Scrub typhus and leptospirosis can cause fever with thrombocytopenia but do not typically produce haemoconcentration with a positive tourniquet test, and HIV seroconversion causes a non-specific rash without plasma leakage.

Question 27Internal Medicine

A 28-year-old woman is admitted with a two-week history of progressive weakness and palpitations. Her pulse is 120/min and irregular, blood pressure 100/60 mmHg, and she has a diffuse goitre with a tremor. Which initial investigation will best confirm the diagnosis?

  1. Transthoracic echocardiography
  2. 24-hour urinary metanephrines
  3. Serum cortisol at 08:00
  4. Serum thyroid-stimulating hormone and free thyroxine Correct answer.

Explanation

The combination of weight loss, tremor, palpitations, a diffuse goitre and atrial fibrillation points to thyrotoxicosis, most often Graves disease in a young woman. A suppressed TSH with elevated free T4 confirms the diagnosis and is the appropriate first-line biochemical test. Echocardiography may show the arrhythmia but does not establish the thyroid cause.

Question 28Internal Medicine

A 55-year-old man with type 2 diabetes has an eGFR of 28 mL/min/1.73 m² and a urine albumin-to-creatinine ratio of 350 mg/g. Which class of antihypertensive medication slows progression of his kidney disease?

  1. Angiotensin-converting enzyme inhibitor Correct answer.
  2. Thiazide diuretic
  3. Beta blocker
  4. Alpha blocker

Explanation

In diabetic kidney disease with albuminuria, an ACE inhibitor (or an angiotensin receptor blocker) reduces intraglomerular pressure and slows the decline in eGFR beyond its blood-pressure-lowering effect. It should be started at a low dose with monitoring of creatinine and potassium. Thiazides, beta blockers and alpha blockers control blood pressure but lack this specific renoprotective action.

Question 29Internal Medicine

A 62-year-old man with chronic obstructive pulmonary disease has an arterial blood gas showing pH 7.28, PaCO₂ 68 mmHg and HCO₃⁻ 30 mmol/L. Which acid–base disturbance is present?

  1. Acute respiratory acidosis with partial metabolic compensation Correct answer.
  2. Metabolic acidosis with respiratory compensation
  3. Mixed metabolic acidosis and metabolic alkalosis
  4. Chronic respiratory alkalosis

Explanation

A raised PaCO₂ with acidaemia indicates respiratory acidosis; the bicarbonate of 30 mmol/L is elevated but not enough to fully correct the pH, indicating partial renal compensation. This pattern is typical of an acute exacerbation of COPD superimposed on chronic CO₂ retention. A purely chronic compensated state would usually show a near-normal pH.

Question 30Internal Medicine

A 48-year-old man presents with sudden-onset pleuritic chest pain and breathlessness two weeks after a below-knee fracture immobilisation. His heart rate is 110/min, oxygen saturation 90% on room air, and the ECG shows sinus tachycardia. Which is the most appropriate next step in management?

  1. Give aspirin 300 mg and arrange an outpatient D-dimer
  2. Start oral amoxicillin and discharge with follow-up
  3. Perform an exercise stress test
  4. Start therapeutic-dose low-molecular-weight heparin while arranging CT pulmonary angiography Correct answer.

Explanation

The presentation is highly suggestive of pulmonary embolism, with risk factors (immobility after fracture), tachycardia and hypoxaemia. In a haemodynamically stable patient with high clinical probability, therapeutic anticoagulation should be started promptly while confirmatory imaging is arranged. D-dimer is unhelpful when clinical probability is high, and antibiotics or stress testing do not address the diagnosis.

Question 31Internal Medicine

A 35-year-old woman has palpitations and a heart rate of 160/min. The ECG shows a narrow-complex tachycardia that is regular, with no visible P waves. She is haemodynamically stable. Which is the most appropriate initial management?

  1. Immediate synchronised DC cardioversion
  2. Vagal manoeuvres, then intravenous adenosine if unsuccessful Correct answer.
  3. Oral digoxin loading
  4. Intravenous amiodarone infusion

Explanation

A regular narrow-complex tachycardia without visible P waves in a stable patient is most likely AV nodal re-entrant tachycardia. Guidelines recommend vagal manoeuvres first, followed by intravenous adenosine if these fail. Synchronised cardioversion is reserved for unstable patients, and amiodarone or digoxin are not first-line for this rhythm.

Question 32Internal Medicine

A 70-year-old man with a history of hypertension presents with sudden weakness of the right arm and leg and expressive aphasia that began 90 minutes ago. Non-contrast CT of the brain shows no haemorrhage. His blood pressure is 170/95 mmHg and his glucose is 6.5 mmol/L. Which is the most appropriate management?

  1. Intravenous thrombolysis with alteplase or tenecteplase Correct answer.
  2. Immediate intravenous heparin infusion
  3. Lower blood pressure to below 120/80 mmHg before any treatment
  4. Aspirin 300 mg only, with no reperfusion therapy

Explanation

An ischaemic stroke within the thrombolysis window (up to 4.5 hours), with no haemorrhage on CT and blood pressure below 185/110 mmHg, is an indication for intravenous thrombolysis. Reperfusion therapy offers the best chance of reducing disability. Aggressive blood pressure lowering before thrombolysis is not recommended, and heparin has no role in acute routine management.

Question 33Internal Medicine

A 33-year-old man has a three-week history of fever, night sweats, weight loss and a productive cough with blood-streaked sputum. Chest radiograph shows upper-lobe cavitation. Which is the most appropriate initial diagnostic test?

  1. Blood cultures
  2. Serum Aspergillus galactomannan
  3. Sputum smear for acid-fast bacilli with Xpert MTB/RIF testing Correct answer.
  4. Sputum cytology

Explanation

The history and upper-lobe cavitation are highly suggestive of pulmonary tuberculosis, which remains a major public health problem in Cambodia. Sputum should be examined for acid-fast bacilli and tested with Xpert MTB/RIF, which also detects rifampicin resistance. Blood cultures and galactomannan are relevant to other infections and do not diagnose TB.

Question 34Internal Medicine

A 24-year-old woman has a three-day history of dysuria and urinary frequency without fever or flank pain. She is not pregnant and has no allergies. Which is the most appropriate treatment?

  1. Intravenous ceftriaxone for seven days
  2. Observation without antibiotics
  3. Oral ciprofloxacin for four weeks
  4. A short course of oral nitrofurantoin or fosfomycin Correct answer.

Explanation

Uncomplicated cystitis in a non-pregnant woman is treated with a short course of oral antibiotics such as nitrofurantoin or a single dose of fosfomycin. These achieve good urinary concentrations with minimal resistance pressure. Intravenous therapy and prolonged courses are reserved for pyelonephritis or complicated infection.

Question 35Internal Medicine

A 60-year-old man with alcoholic cirrhosis presents with haematemesis and melaena. His blood pressure is 95/60 mmHg and heart rate 115/min. After resuscitation, which medication should be started before endoscopy?

  1. Intravenous furosemide
  2. Oral propranolol
  3. Intravenous terlipressin or octreotide Correct answer.
  4. Intravenous vitamin K alone

Explanation

In suspected variceal bleeding from portal hypertension, a vasoactive agent such as terlipressin or octreotide should be started as soon as possible, before endoscopy, to reduce portal pressure and bleeding. Prophylactic antibiotics are also given. Beta blockers are used for prophylaxis of bleeding, not in the acute phase.

Question 36Internal Medicine

A 45-year-old woman has recurrent episodes of severe epigastric pain radiating to the back, with vomiting and elevated serum lipase. She drinks no alcohol and has no gallstones on ultrasound. Which additional factor is most likely to explain her recurrent pancreatitis?

  1. Hypercalcaemia
  2. Hypertriglyceridaemia Correct answer.
  3. Hyperuricaemia
  4. Hyperthyroidism

Explanation

After gallstones and alcohol, hypertriglyceridaemia is a leading cause of recurrent acute pancreatitis, usually with triglycerides above 11 mmol/L. Hypercalcaemia (for example from hyperparathyroidism) is a recognised but less common cause. Hyperthyroidism and hyperuricaemia are not established causes of pancreatitis.

Question 37Internal Medicine

A 25-year-old man is brought to the emergency department after a heroin overdose. He has pinpoint pupils, a respiratory rate of 6/min and oxygen saturation of 82%. Naloxone is given and he improves, but 40 minutes later he becomes drowsy again with a respiratory rate of 8/min. What is the best explanation for this deterioration?

  1. Naloxone has precipitated a seizure
  2. He has developed aspiration pneumonia immediately
  3. Naloxone has caused a paradoxical opioid effect
  4. The naloxone effect has worn off while opioid is still present Correct answer.

Explanation

Naloxone has a short half-life (about 30–90 minutes), shorter than many opioids, so its antagonism wears off while opioid remains in the body, causing recurrent respiratory depression. Patients require monitoring and repeat doses or an infusion. Aspiration pneumonia would not typically recur within 40 minutes with pinpoint pupils, and naloxone does not cause opioid effects or seizures.

Question 38Internal Medicine

A 68-year-old man with heart failure and an ejection fraction of 30% remains breathless despite an ACE inhibitor and a beta blocker. His eGFR is 45 mL/min/1.73 m² and potassium is 4.8 mmol/L. Which additional medication improves survival in this setting?

  1. Amlodipine
  2. Furosemide
  3. Spironolactone Correct answer.
  4. Digoxin

Explanation

A mineralocorticoid receptor antagonist such as spironolactone improves survival in heart failure with reduced ejection fraction and should be added when renal function and potassium allow. Potassium and creatinine must be monitored. Amlodipine and furosemide relieve symptoms but do not improve mortality, and digoxin reduces hospitalisation but not mortality.

Question 39Internal Medicine

A 30-year-old woman has a two-day history of fever, headache, neck stiffness and photophobia. Lumbar puncture shows a raised opening pressure, 1,200 white cells/µL with 90% lymphocytes, a protein of 100 mg/dL and a glucose of 1.8 mmol/L with a serum glucose of 5.5 mmol/L. Which organism is most likely?

  1. Streptococcus pneumoniae
  2. Cryptococcus neoformans Correct answer.
  3. Herpes simplex virus type 1
  4. Neisseria meningitidis

Explanation

A lymphocytic pleocytosis with markedly low cerebrospinal fluid glucose and raised protein suggests a fungal or tuberculous meningitis; Cryptococcus neoformans is a common cause in immunocompromised patients and in Cambodia. Bacterial meningitis typically shows neutrophilic pleocytosis with low glucose, while viral meningitis usually has normal glucose.

Question 40Internal Medicine

A 50-year-old woman with a history of treated breast cancer presents with confusion, polyuria and constipation. Her serum calcium is 3.4 mmol/L and she is dehydrated. After intravenous saline, which is the most appropriate next step?

  1. Intravenous furosemide as first-line therapy
  2. Oral vitamin D
  3. Intravenous bisphosphonate such as zoledronic acid Correct answer.
  4. Oral calcium supplementation

Explanation

Severe hypercalcaemia of malignancy requires aggressive intravenous fluid replacement followed by an intravenous bisphosphonate, which inhibits osteoclast-mediated bone resorption. Furosemide is used only after volume repletion in selected patients and can worsen dehydration. Calcium and vitamin D would exacerbate the hypercalcaemia.

Question 41Surgery and Traumatology

A 25-year-old man is stabbed in the left fifth intercostal space at the anterior axillary line. He is hypotensive and has distended neck veins. Which diagnosis should be suspected first?

  1. Aortic dissection
  2. Diaphragmatic rupture
  3. Tension pneumothorax
  4. Cardiac tamponade Correct answer.

Explanation

Penetrating trauma to the precordial region with hypotension and distended neck veins suggests cardiac tamponade, which is common with wounds near the heart. Tension pneumothorax could also cause hypotension and distended neck veins, but the wound location at the anterior axillary line is less typical for a precordial injury causing tamponade than for a lung injury. The combination of a wound over the heart and shock with raised jugular venous pressure should prompt urgent pericardial assessment.

Question 42Surgery and Traumatology

Which finding is most reliable for early recognition of compartment syndrome in a patient with a closed tibial fracture?

  1. Severe pain out of proportion to the injury Correct answer.
  2. Visible swelling of the calf
  3. Absent distal pulse
  4. Mild paresthesia in the toes

Explanation

The earliest and most reliable clinical sign of compartment syndrome is severe pain that is out of proportion to the injury and increased by passive stretch. Pulselessness is a late sign because arterial pressure usually remains above compartment pressure until very late. Swelling and mild paresthesia are nonspecific and can occur with many fractures.

Question 43Surgery and Traumatology

A patient has a 3 cm laceration over the scalp with active bleeding and no neurological deficit. Which initial step is most appropriate?

  1. Immediate CT scan of the head
  2. Suture without cleaning
  3. Prophylactic antibiotics alone
  4. Direct pressure and wound exploration Correct answer.

Explanation

The first priority in a bleeding scalp laceration is control of hemorrhage with direct pressure and careful exploration of the wound for foreign bodies or galea injury. CT imaging is reserved for suspected skull fracture or neurological deficit. Antibiotics alone do not control bleeding, and suturing without cleaning risks infection.

Question 44Surgery and Traumatology

Which is the most appropriate initial management of a patient with a suspected open fracture of the tibia?

  1. Delayed wound closure after 72 hours
  2. Immediate internal fixation before debridement
  3. Application of a tight plaster cast
  4. Antibiotics, tetanus prophylaxis, and urgent debridement Correct answer.

Explanation

Open fractures require early intravenous antibiotics, tetanus prophylaxis, and urgent surgical debridement and irrigation. Internal fixation is not performed before adequate debridement because of infection risk. Tight casting can compromise perfusion, and delayed closure is not the initial priority.

Question 45Surgery and Traumatology

A 40-year-old woman has right upper quadrant pain, fever, and jaundice. Ultrasound shows a dilated common bile duct with stones. Which diagnosis is most likely?

  1. Acute cholecystitis
  2. Peptic ulcer disease
  3. Cholangitis Correct answer.
  4. Acute pancreatitis

Explanation

The combination of right upper quadrant pain, fever, and jaundice, with a dilated common bile duct containing stones, is the classic presentation of ascending cholangitis. Acute cholecystitis usually causes pain and fever without jaundice. Pancreatitis and peptic ulcer disease do not typically cause ductal dilatation with stones and jaundice.

Question 46Surgery and Traumatology

Which is the most appropriate initial fluid resuscitation for an adult with major burns covering 30% of total body surface area?

  1. Ringer's lactate calculated by the Parkland formula Correct answer.
  2. 5% dextrose in water at maintenance rate
  3. No fluids until urine output is measured
  4. Hypertonic saline at 500 mL per hour

Explanation

Major burns are resuscitated with isotonic crystalloid, usually Ringer's lactate, using the Parkland formula (4 mL/kg/% burn) in the first 24 hours. Dextrose solutions do not replace intravascular volume and can worsen hyponatremia. Hypertonic saline is not the standard initial fluid, and fluid therapy should not be delayed.

Question 47Surgery and Traumatology

A patient presents with a painful, swollen leg after prolonged immobilization. Which diagnostic test is most appropriate to confirm deep vein thrombosis?

  1. Duplex venous ultrasound Correct answer.
  2. Plain radiograph of the leg
  3. Serum D-dimer alone
  4. Arterial blood gas

Explanation

Duplex venous ultrasound is the imaging test of choice for suspected deep vein thrombosis because it assesses venous compressibility and flow. Plain radiographs do not show thrombus. D-dimer is useful for exclusion in low-risk patients but is not confirmatory. Arterial blood gas does not diagnose deep vein thrombosis.

Question 48Surgery and Traumatology

A 60-year-old man has a painless, hard testicular mass. Which tumor marker is most useful in follow-up?

  1. Alpha-fetoprotein
  2. Beta-human chorionic gonadotropin Correct answer.
  3. Carcinoembryonic antigen
  4. Lactate dehydrogenase

Explanation

Beta-human chorionic gonadotropin is a key tumor marker for testicular germ cell tumors, particularly choriocarcinoma and mixed tumors, and is used in staging and follow-up. Alpha-fetoprotein is also used for yolk sac elements, but beta-hCG is the most useful marker for many testicular tumors. Lactate dehydrogenase is nonspecific, and carcinoembryonic antigen is used mainly in colorectal cancer.

Question 49Surgery and Traumatology

Which is the most appropriate management of a patient with a small, uncomplicated appendiceal abscess after appendicitis?

  1. Percutaneous drainage with antibiotics Correct answer.
  2. Observation without treatment
  3. Radiotherapy
  4. Immediate open appendectomy

Explanation

A small, well-defined appendiceal abscess can be managed with percutaneous drainage and intravenous antibiotics, followed by interval appendectomy if needed. Immediate open appendectomy in the presence of an abscess increases morbidity. Observation alone risks sepsis, and radiotherapy has no role.

Question 50Surgery and Traumatology

A patient has a penetrating abdominal wound with evisceration of bowel. Which is the most appropriate initial management?

  1. Oral fluids and observation
  2. Wound exploration in the emergency department
  3. Discharge with antibiotics
  4. Immediate laparotomy Correct answer.

Explanation

Evisceration after penetrating abdominal trauma is an indication for immediate laparotomy because of the high risk of visceral injury. Wound exploration in the emergency department is inadequate and may worsen contamination. Oral fluids and observation or discharge are unsafe in this setting.