Free Internal Medicine mock test

Internal Medicine sample questions with answers

10 more original exam-style Internal Medicine questions, worked in full. They are not real or recalled exam questions, and none of them is in the mock above or on the bank page, so sit the mock first if you have not.

1. Question 1 · Pulmonary and Respiratory Diseases

   A 62-year-old man with a 40 pack-year smoking history has a CT for abdominal pain that incidentally shows a single solid, smooth-edged 7 mm nodule in the right upper lobe. There is no lymphadenopathy, no prior imaging for comparison, and he is asymptomatic with no history of malignancy. Following the Fleischner Society recommendations, what is the most appropriate management?

   1. ANo further imaging follow-up is required
   2. BImmediate CT-guided percutaneous biopsy
   3. CPET-CT within 2 weeks followed by surgical resection if avid
   4. DRepeat CT at 6 to 12 months, then consider CT at 18 to 24 months
   Show answer and explanation

   Correct answer: D. Repeat CT at 6 to 12 months, then consider CT at 18 to 24 months

   For a single solid nodule of 6 to 8 mm in a high-risk patient, the Fleischner Society advises a follow-up CT at 6 to 12 months and then at 18 to 24 months, since growth over time is the key discriminator at this size. Discharging without follow-up applies only to solid nodules under 6 mm in low-risk patients. Biopsy and PET-CT have poor yield and accuracy for sub-centimetre nodules and expose the patient to unnecessary risk before growth is demonstrated.

   Reference: Fleischner Society Guidelines for Management of Incidental Pulmonary Nodules Detected on CT Images, Radiology 2017

2. Question 2 · Infectious Diseases

   A 51-year-old man has been neutropenic for 16 days after induction chemotherapy and remains febrile despite six days of piperacillin-tazobactam. High-resolution chest CT shows two nodules with surrounding ground-glass haloes, and serum galactomannan is strongly positive on two occasions. What is the most appropriate treatment?

   1. AFluconazole
   2. BCaspofungin monotherapy as first-line
   3. CVoriconazole (or isavuconazole)
   4. DContinue antibacterials alone and repeat CT in two weeks
   Show answer and explanation

   Correct answer: C. Voriconazole (or isavuconazole)

   The halo sign in a prolonged-neutropenic patient with positive galactomannan indicates probable invasive pulmonary aspergillosis, for which voriconazole or isavuconazole is first-line, with liposomal amphotericin B as an alternative. Fluconazole has no activity against Aspergillus, echinocandins are salvage or combination agents rather than preferred monotherapy, and observation alone in this setting carries very high mortality.

   Reference: IDSA Practice Guideline for the Diagnosis and Management of Aspergillosis, 2016; ECIL-6/ESCMID-ECMM-ERS Aspergillosis Guideline 2018

3. Question 3 · Nephrology, Fluids and Electrolytes

   A 34-year-old woman with Sjogren syndrome has muscle weakness. Investigations show sodium 140 mmol/L, chloride 116 mmol/L, bicarbonate 15 mmol/L, potassium 2.8 mmol/L and a normal anion gap. Urine pH is 6.5 despite the systemic acidosis, and renal ultrasound demonstrates nephrocalcinosis. What is the most likely diagnosis?

   1. AType 2 (proximal) renal tubular acidosis
   2. BType 4 (hyperkalaemic) renal tubular acidosis
   3. CChronic diarrhoeal bicarbonate loss
   4. DType 1 (distal) renal tubular acidosis
   Show answer and explanation

   Correct answer: D. Type 1 (distal) renal tubular acidosis

   Inability to acidify the urine below pH 5.5 in the face of systemic metabolic acidosis, together with hypokalaemia and nephrocalcinosis, is diagnostic of distal (type 1) RTA, which is classically associated with Sjogren syndrome. Proximal RTA causes bicarbonate wasting with a urine pH that falls below 5.5 once the filtered load drops below the reabsorptive threshold, and is associated with Fanconi syndrome rather than nephrocalcinosis. Type 4 RTA produces hyperkalaemia, not hypokalaemia, and gastrointestinal bicarbonate loss is accompanied by an appropriately acidic urine.

   Reference: Harrison's Principles of Internal Medicine, 21st edition (2022); Brenner and Rector's The Kidney, 11th edition (2020)

4. Question 4 · Emergency and Critical Care Medicine

   A 52-year-old woman admitted to ICU with severe pneumonia has improved: she is extubated, off vasopressors for 24 hours, alert, saturating 95 percent on 2 L/min nasal oxygen and passing good urine. Which of the following most appropriately guides the decision to step her down to the ward?

   1. AKeep her in ICU for a mandatory minimum of 7 days after extubation regardless of progress
   2. BDischarge only once she requires no supplemental oxygen at all and all laboratory results are normal
   3. CDischarge when organ support is no longer required and her physiology is stable, ideally during daytime hours with a structured handover and clear escalation plan
   4. DDischarge overnight to free the bed, as timing of discharge does not influence outcome
   Show answer and explanation

   Correct answer: C. Discharge when organ support is no longer required and her physiology is stable, ideally during daytime hours with a structured handover and clear escalation plan

   Step-down is appropriate once the need for organ support has resolved and physiology is stable, with the transfer supported by a structured handover, a documented escalation plan and follow-up, since low-oxygen requirements are readily managed on a ward. Night-time ICU discharge is consistently associated with higher readmission and mortality and should be avoided where possible. Demanding entirely normal results or applying an arbitrary fixed length of stay wastes a scarce resource and exposes the patient to avoidable ICU-acquired complications.

   Reference: SCCM Guidelines for ICU Admission, Discharge and Triage (2016); NICE Clinical Guideline CG50 and NICE NG94 on emergency and acute care; Vollam et al., Intensive Care Medicine 2018, out-of-hours ICU discharge

5. Question 5 · Neurology and Neuroscience

   A 63-year-old woman with amyotrophic lateral sclerosis reports orthopnoea, disturbed sleep with frequent waking, and morning headaches. Forced vital capacity is 48% predicted, sniff nasal inspiratory pressure is reduced and morning arterial blood gas shows a pCO2 of 6.9 kPa. Bulbar function is only mildly affected. Which intervention is most likely to improve both survival and quality of life?

   1. AElective tracheostomy and invasive ventilation for all patients at this stage
   2. BNo respiratory intervention, since ventilatory support does not alter outcome in this disease
   3. CNon-invasive ventilation
   4. DLong-term oxygen therapy alone
   Show answer and explanation

   Correct answer: C. Non-invasive ventilation

   Nocturnal hypoventilation with orthopnoea, morning headache, FVC below 50% predicted and hypercapnia is the accepted trigger for non-invasive ventilation in ALS, which improves survival and quality of life, particularly when bulbar involvement is mild. Oxygen given alone suppresses hypoxic respiratory drive and worsens carbon dioxide retention in neuromuscular hypoventilation. Tracheostomy ventilation is a highly individualised later option requiring extensive discussion rather than a routine step, and doing nothing forgoes a proven benefit.

   Reference: NICE NG42 Motor neurone disease (2016); Bourke SC et al., Effects of non-invasive ventilation on survival and quality of life in ALS, Lancet Neurology 2006

6. Question 6 · Patient Safety, Quality and Evidence-Based Practice

   A guideline panel is using the GRADE approach. Which circumstance would justify rating UP the certainty of evidence derived from observational studies?

   1. AThe studies were unblinded and outcome assessors knew the exposure status
   2. BThere was substantial unexplained statistical heterogeneity between the studies
   3. CA large magnitude of effect with a dose-response gradient, where plausible residual confounding would have reduced rather than created the observed effect
   4. DThe reported outcome was a surrogate laboratory marker rather than a patient-important outcome
   Show answer and explanation

   Correct answer: C. A large magnitude of effect with a dose-response gradient, where plausible residual confounding would have reduced rather than created the observed effect

   GRADE starts observational evidence at low certainty but allows upgrading for a large magnitude of effect, a dose-response gradient, or plausible confounding that would bias the result towards the null. Lack of blinding is a risk-of-bias problem, unexplained heterogeneity is inconsistency, and a surrogate endpoint is indirectness - all three are reasons to rate certainty down, not up. Recognising that strength of recommendation and certainty of evidence are separate judgments is central to GRADE.

   Reference: Guyatt GH et al. GRADE: an emerging consensus on rating quality of evidence and strength of recommendations. BMJ 2008;336:924-926

7. Question 7 · Cardiovascular Medicine

   A 29-year-old man with a large unrepaired ventricular septal defect has central cyanosis, digital clubbing, oxygen saturation of 82% on air and a loud single second heart sound with no murmur. Haemoglobin is 20.5 g/dL. Catheterisation shows suprasystemic pulmonary vascular resistance with bidirectional shunting that is predominantly right-to-left. What is the most appropriate management?

   1. ASurgical closure of the ventricular septal defect
   2. BRoutine venesection to normalise the haemoglobin concentration
   3. CReferral to a specialist pulmonary hypertension and adult congenital heart disease centre for advanced therapy such as bosentan
   4. DLong-term warfarin for all patients regardless of other indications
   Show answer and explanation

   Correct answer: C. Referral to a specialist pulmonary hypertension and adult congenital heart disease centre for advanced therapy such as bosentan

   This is Eisenmenger syndrome, in which the defect acts as a decompressive vent for the suprasystemic pulmonary circulation, so closure is contraindicated and precipitates right ventricular failure and death. Management is at a specialist centre, and endothelin receptor antagonists such as bosentan improve exercise capacity and haemodynamics. Secondary erythrocytosis is compensatory and routine venesection causes iron deficiency and stroke risk, and routine anticoagulation is not recommended because of haemoptysis and bleeding risk.

   Reference: ESC Guidelines for the Management of Adult Congenital Heart Disease, 2020; ESC/ERS Pulmonary Hypertension Guidelines, 2022

8. Question 8 · Gastroenterology and Hepatology

   A 44-year-old man who drinks 150 g of alcohol daily presents with jaundice of three weeks' duration. Bilirubin is 320 micromol/L, AST 160 U/L, ALT 70 U/L, INR 2.0, creatinine 90 micromol/L and neutrophils 14 x10^9/L. His Maddrey discriminant function is 58 and there is no evidence of infection or gastrointestinal bleeding. What is the most appropriate treatment?

   1. APrednisolone 40 mg daily with reassessment using the Lille score at day 7
   2. BPentoxifylline 400 mg three times daily
   3. CIntravenous N-acetylcysteine monotherapy for 72 hours
   4. DInfliximab 5 mg/kg as a single infusion
   Show answer and explanation

   Correct answer: A. Prednisolone 40 mg daily with reassessment using the Lille score at day 7

   Severe alcohol-associated hepatitis (Maddrey discriminant function of 32 or more, or MELD above 20) without contraindication is treated with prednisolone 40 mg daily, with the Lille score at day 7 used to decide whether to continue or stop for non-response. The AST:ALT ratio above 2 with AST usually below 400 U/L is characteristic. Pentoxifylline did not improve survival in the STOPAH trial and is no longer recommended. NAC may be used as an adjunct to steroids but not as monotherapy. Anti-TNF agents such as infliximab increase infection and mortality in this setting.

   Reference: Thursz et al., STOPAH Trial, New England Journal of Medicine, 2015; EASL Clinical Practice Guidelines on Alcohol-Related Liver Disease, 2018; ACG Clinical Guideline on Alcohol-Associated Liver Disease, 2024

9. Question 9 · Endocrinology, Diabetes and Metabolism

   A 29-year-old nurse without diabetes is admitted after her third episode of unexplained coma with a documented plasma glucose of 1.7 mmol/L. Samples taken at the time of hypoglycaemia show insulin 340 mIU/L, C-peptide less than 0.05 nmol/L, negative sulfonylurea and meglitinide screen, and a normal morning cortisol. Which diagnosis best explains these findings?

   1. AInsulinoma
   2. BFactitious hypoglycaemia from surreptitious exogenous insulin
   3. CSulfonylurea-induced hypoglycaemia
   4. DPrimary adrenal insufficiency
   Show answer and explanation

   Correct answer: B. Factitious hypoglycaemia from surreptitious exogenous insulin

   Markedly elevated insulin with a fully suppressed C-peptide indicates that the insulin is exogenous, since endogenously secreted insulin is co-released with C-peptide in equimolar amounts. An insulinoma or sulfonylurea-induced hypoglycaemia would both raise C-peptide, and the drug screen was negative. Adrenal insufficiency causes hypoglycaemia with suppressed rather than elevated insulin, and the cortisol is normal here.

   Reference: Endocrine Society Clinical Practice Guideline, Evaluation and Management of Adult Hypoglycemic Disorders (2009); Harrison's Principles of Internal Medicine, 21st edition (2022)

10. Question 10 · Rheumatology and Clinical Immunology

    A 48-year-old woman with long-standing late-onset asthma and chronic rhinosinusitis develops mononeuritis multiplex with a wrist drop, migratory pulmonary infiltrates, and an eosinophil count of 6.8 x 10^9/L. Which diagnosis is most likely?

    1. AAllergic bronchopulmonary aspergillosis
    2. BGranulomatosis with polyangiitis
    3. CChronic eosinophilic pneumonia
    4. DEosinophilic granulomatosis with polyangiitis
    Show answer and explanation

    Correct answer: D. Eosinophilic granulomatosis with polyangiitis

    Adult-onset asthma with sinus disease, marked peripheral eosinophilia, fleeting pulmonary infiltrates and vasculitic neuropathy such as mononeuritis multiplex is characteristic of eosinophilic granulomatosis with polyangiitis (Churg-Strauss). Allergic bronchopulmonary aspergillosis causes central bronchiectasis and mucus plugging with raised aspergillus-specific IgE but does not cause vasculitic neuropathy. Granulomatosis with polyangiitis features destructive granulomatous upper airway disease without eosinophilia, and chronic eosinophilic pneumonia lacks extrapulmonary vasculitic manifestations.

    Reference: ACR/EULAR 2022 classification criteria for eosinophilic granulomatosis with polyangiitis (Ann Rheum Dis 2022)