Why a fever that returns after a chest infection matters
When a chest infection seems to settle and then the fever comes back, something has gone wrong: the wrong drug, too short a course, a collection of pus, or a different disease underneath. Each needs a different plan, so find out which.
What to ask in the history
- The first illness: symptoms, antibiotics, how long he took them and why he stopped
- Fever pattern, sweats, shivering
- Sputum: how much, colour, smell, blood
- Chest pain on breathing, breathlessness
- Weight loss, appetite
- Alcohol and smoking
- Teeth and gums
- Diabetes, HIV, contact with tuberculosis
Red flags
- Low oxygen saturation or breathless at rest
- Low blood pressure, confusion
- Large amounts of foul sputum
- Coughing up blood
- Signs of fluid in the chest
What to examine
- Observations
- Nutrition, teeth and gums
- Chest: expansion, dullness, breath sounds, crackles
- Clubbing, lymph nodes
First investigations
- Chest X-ray
- Full blood count, CRP
- Blood cultures
- Sputum culture and tuberculosis tests
- Ultrasound of the chest, and a sample of any fluid
- CT chest
- HIV test, glucose
Differential diagnosis of a fever that returns after a chest infection
Grouped, not ranked. Which one fits this patient is for you to work out in the case.
A different organism
- Tuberculosis
- Resistant bacteria
- Fungal infection
Complications
- Parapneumonic effusion or empyema
- Lung abscess
Something underneath
- Lung cancer blocking an airway
- Aspiration
- Bronchiectasis
Elsewhere
- Drug fever
- Another infection
- Pulmonary embolism
Common mistakes
- Simply restarting the same antibiotic.
- Missing fluid in the chest that needs draining.
- Forgetting tuberculosis.