Infectious Disease OSCE: Clinical Presentation and Management

Posted on Jul 11, 2026 in Medicine

1. Malaria: Fever and Travel

Key History Clues

  • Recent travel to sub-Saharan Africa or South Asia
  • Mosquito exposure
  • Fever with chills and rigors
  • Cyclical fever patterns
  • Headache and myalgia
  • Possible confusion (indicative of severe malaria)

Investigations

  • Thick and thin blood film (gold standard)
  • Malaria rapid antigen test
  • FBC (thrombocytopenia is common)
  • U&Es, LFTs, and glucose (to assess severity)
  • Blood cultures (to rule out sepsis)

Management

  • Admit if suspected
  • IV artesunate for severe malaria
  • Oral ACT (artemisinin-based combination therapy) for uncomplicated cases
  • IV fluids and antipyretics
  • Monitor glucose and renal function

2. Typhoid Fever

Key History Clues

  • Travel to India, Pakistan, Bangladesh, or Africa
  • Unsafe food or water consumption
  • Gradual onset of fever
  • Abdominal pain, diarrhea, or constipation
  • Headache and malaise
  • Possible “rose spot” rash

Investigations

  • Blood cultures (most important early test)
  • Stool culture (useful later)
  • FBC (leucopenia may occur)
  • LFTs

Management

  • Antibiotics: ceftriaxone or azithromycin
  • Fluids and supportive care
  • Notify public health authorities (essential OSCE point)

3. Legionella Pneumonia

Key History Clues

  • “Atypical pneumonia” presentation
  • Recent stay in hotels, cruises, spas, or air conditioning exposure
  • Fever, cough, and breathlessness
  • GI symptoms: diarrhea
  • Confusion (common in the elderly)
  • Relative bradycardia

Investigations

  • Urinary antigen test (key OSCE answer)
  • CXR (patchy or atypical pneumonia)
  • Bloods: Elevated CRP, hyponatremia
  • Sputum culture (less sensitive)

Management

  • Macrolide (azithromycin) or fluoroquinolone
  • Oxygen therapy as required
  • Admit if moderate or severe

4. Measles

Key History Clues

  • Unvaccinated status (check MMR history)
  • Fever, cough, coryza, and conjunctivitis
  • Rash starting on the face and spreading downwards
  • Koplik spots (pathognomonic)

Investigations

  • Clinical diagnosis (often sufficient)
  • Measles IgM serology (for confirmation)
  • FBC (lymphopenia may occur)

Management

  • Supportive care (fluids, antipyretics)
  • Isolation (highly infectious)
  • Vitamin A supplementation in children

5. Tuberculosis

Key History Clues

  • Chronic cough (>3 weeks)
  • Weight loss, night sweats, and fever
  • Known TB contact
  • Immunosuppression, homelessness, or travel history

Investigations

  • Sputum AFB smear and culture
  • NAAT (PCR-based test)
  • CXR (upper lobe cavitation)
  • IGRA or Mantoux test (for latent TB)

Management

  • RIPE therapy:
    • Rifampicin
    • Isoniazid
    • Pyrazinamide
    • Ethambutol
  • Public health notification and contact tracing
  • Initial isolation

6. Meningitis

Key History Clues

  • Fever, headache, and neck stiffness
  • Photophobia
  • Rash (meningococcal: non-blanching)
  • Confusion

Investigations

  • Blood cultures
  • CT head (if indicated)
  • Lumbar puncture (CSF analysis)
  • FBC and CRP

Management

  • Immediate IV ceftriaxone
  • Dexamethasone (administered before or with antibiotics)
  • Do NOT delay antibiotics for LP if suspected
  • Public health prophylaxis for contacts

7. HIV

Key History Clues

  • Recurrent infections
  • Weight loss, fever, and night sweats
  • Risk factors:
    • Unprotected sex
    • Multiple partners
    • IV drug use
    • Blood exposure

Investigations

  • HIV 4th generation test
  • CD4 count
  • Viral load
  • STI screen
  • FBC and LFTs

Management

  • Combination ART (specialist-led)
  • Opportunistic infection prophylaxis based on CD4 count
  • Counselling and psychological support