Chest Infection

1. Overview

Chest infection is a broad clinical term commonly used for lower respiratory tract infection. It includes acute bronchitis and pneumonia. In an OSCE, the main task is to assess severity, decide whether pneumonia is likely, identify risk factors and determine whether the patient can be managed in the community or needs urgent hospital assessment.

Acute bronchitis usually causes cough with or without sputum and is often viral. Pneumonia is infection of the lung parenchyma and is more likely when cough is associated with fever, breathlessness, pleuritic chest pain, focal chest signs, hypoxia or systemic illness.

Key OSCE priorities

• Assess whether the patient is acutely unwell or septic.
• Ask about cough, sputum, fever, pleuritic chest pain and breathlessness.
• Ask about haemoptysis.
• Check oxygen saturation early.
• Look for focal chest signs suggesting pneumonia.
• Assess risk factors such as age, COPD, asthma, immunosuppression and aspiration risk.
• Use clinical judgement and pneumonia severity scoring when pneumonia is suspected.
• Consider alternative diagnoses such as PE, heart failure, TB and malignancy.
• Discuss antibiotics only when bacterial infection or pneumonia is suspected according to local guidance.

Important causes and related diagnoses

• Acute bronchitis.
• Community-acquired pneumonia.
• Hospital-acquired pneumonia.
• Aspiration pneumonia.
• COPD exacerbation.
• Asthma exacerbation triggered by infection.
• Bronchiectasis exacerbation.
• Influenza or COVID-19 depending on local epidemiology.
• Tuberculosis.
• Pulmonary embolism mimicking infection.
• Lung cancer presenting with recurrent infection.
• Heart failure mimicking chest infection.

Red flag features

• Severe breathlessness.
• Oxygen desaturation.
• Respiratory rate 30 or more.
• Confusion.
• Hypotension.
• Cyanosis.
• Chest pain.
• Haemoptysis.
• Sepsis features.
• Reduced oral intake or dehydration.
• Immunosuppression.
• Recurrent pneumonia.
• Weight loss or night sweats.

2. History Taking

Opening

• Wash hands.
• Introduce yourself.
• Confirm patient identity.
• Explain that you would like to ask about the chest infection symptoms.
• Gain consent.
• Check whether the patient is currently very breathless, confused, has chest pain, haemoptysis or feels faint.
• If acutely unwell, state that you would assess using ABCDE and call for senior help.

Presenting complaint

• Ask when the symptoms started.
• Ask whether onset was sudden or gradual.
• Ask whether symptoms are worsening, improving or persistent.
• Ask about cough.
• Ask whether the cough is dry or productive.
• Ask about sputum colour, amount and smell.
• Ask about fever or rigors.
• Ask about shortness of breath.
• Ask about chest pain.
• Ask whether this has happened before.

Cough and sputum

• Dry or productive cough.
• Sputum colour: clear, white, yellow, green, rusty or blood-stained.
• Sputum volume.
• Foul-smelling sputum suggesting anaerobic infection or aspiration.
• Large-volume sputum suggesting bronchiectasis.
• Duration of cough.
• Nocturnal cough.
• Change from baseline cough in COPD or bronchiectasis.

Symptoms suggesting pneumonia

• Fever.
• Rigors.
• Productive cough.
• Pleuritic chest pain.
• Shortness of breath.
• Reduced exercise tolerance.
• Malaise.
• Confusion, especially in older patients.
• Reduced oral intake.
• Focal chest symptoms.

Severity assessment

• Ask whether the patient is breathless at rest.
• Ask whether they can speak in full sentences.
• Ask about reduced exercise tolerance.
• Ask about confusion or drowsiness.
• Ask about dizziness, collapse or fainting.
• Ask about reduced urine output.
• Ask whether they are drinking fluids normally.
• Ask about frailty and ability to manage at home.

CRB65 / CURB65 features

• Confusion.
• Respiratory rate 30 breaths per minute or more.
• Low blood pressure.
• Age 65 years or older.
• Urea above 7 mmol/L if blood tests are available for CURB65.
• Use the score with clinical judgement, comorbidities and social factors.

Associated respiratory symptoms

• Wheeze.
• Chest tightness.
• Haemoptysis.
• Pleuritic chest pain.
• Hoarseness.
• Night sweats.
• Weight loss.
• Recurrent infections.
• Symptoms of upper respiratory tract infection such as sore throat, runny nose or sinus symptoms.

COPD or asthma exacerbation screen

• Known asthma or COPD.
• Increased wheeze.
• Increased breathlessness.
• Increased reliever inhaler use.
• Change in sputum colour or volume.
• Previous hospital admissions.
• Previous ICU or ventilation.
• Home oxygen or nebuliser use.
• Inhaler adherence and technique.

Aspiration risk screen

• Choking episodes.
• Difficulty swallowing.
• Coughing during meals.
• Recent vomiting.
• Reduced consciousness.
• Alcohol excess.
• Neurological disease such as stroke or Parkinson disease.
• Poor dentition.
• Recent anaesthesia or sedation.

Tuberculosis screen

• Cough lasting several weeks.
• Haemoptysis.
• Fever.
• Night sweats.
• Weight loss.
• Loss of appetite.
• Previous TB.
• TB contact.
• Travel or residence in a high TB prevalence area.
• HIV risk or immunosuppression.

Lung cancer screen

• Persistent cough.
• Change in chronic smoker's cough.
• Haemoptysis.
• Unexplained weight loss.
• Loss of appetite.
• Hoarseness.
• Recurrent pneumonia in the same area.
• Chest pain.
• Finger clubbing.
• Smoking history.
• Asbestos exposure.

Pulmonary embolism screen

• Sudden breathlessness.
• Pleuritic chest pain.
• Haemoptysis.
• Syncope or collapse.
• Unilateral leg swelling or calf pain.
• Recent surgery.
• Recent immobility or long-haul travel.
• Active cancer.
• Previous DVT or PE.
• Pregnancy or postpartum period.
• Oestrogen therapy.

Heart failure screen

• Orthopnoea.
• Paroxysmal nocturnal dyspnoea.
• Ankle swelling.
• Pink frothy sputum.
• Nocturnal cough.
• Known ischaemic heart disease.
• Hypertension.
• Valvular heart disease.
• Previous heart failure.

Past medical history

• Asthma.
• COPD.
• Bronchiectasis.
• Previous pneumonia.
• Tuberculosis.
• Lung cancer.
• Interstitial lung disease.
• Heart failure.
• Diabetes mellitus.
• Chronic kidney disease.
• Stroke or swallowing problems.
• HIV or immunosuppression.
• Recent hospital admission.
• Vaccination status if relevant.

Drug history and allergies

• Current regular medications.
• Inhalers and adherence.
• Recent antibiotics.
• Recent oral steroids.
• Immunosuppressants.
• Chemotherapy.
• Anticoagulants if haemoptysis is present.
• ACE inhibitors if chronic cough is present.
• Drug allergies and reaction.
• Antibiotic allergies specifically.

Family history

• Asthma or atopy.
• COPD.
• Bronchiectasis.
• Tuberculosis contact in household.
• Lung cancer.
• Inherited lung disease if relevant.

Social history

• Smoking status and pack-year history.
• Vaping.
• Alcohol intake.
• Recreational drug use.
• Occupation and dust, chemical or asbestos exposure.
• Living situation and support.
• Care home residence.
• Ability to maintain oral intake.
• Baseline mobility and independence.
• Sick contacts.
• Recent travel.
• Pets, birds or mould exposure.

Ideas, concerns and expectations

• Ask what the patient thinks is causing the symptoms.
• Ask what they are most worried about.
• Ask whether they are concerned about pneumonia, TB, cancer or COVID-like illness.
• Ask what they were hoping would happen today.
• Acknowledge concerns and explain that severity and cause need to be assessed.

Red flags

• Severe breathlessness.
• Unable to speak in full sentences.
• Confusion.
• Cyanosis.
• Chest pain.
• Haemoptysis.
• Persistent fever or rigors.
• Hypotension or collapse.
• Reduced urine output.
• Immunosuppression.
• Weight loss or night sweats.
• Recurrent pneumonia.

Closing the history

• Summarise the key points back to the patient.
• Ask if they would like to add anything else.
• Thank the patient.
• State that you would check observations, oxygen saturation, examine the respiratory system and arrange investigations depending on severity.

3. Physical Examination

The examination should assess severity, oxygenation, sepsis, pneumonia signs, pleural complications and alternative diagnoses such as asthma, COPD, PE and heart failure.

Before starting the examination

• Wash hands or use alcohol gel.
• Introduce yourself with name and role.
• Confirm the patient's identity.
• Explain the examination clearly.
• Gain consent.
• Ask whether the patient has chest pain, severe breathlessness or feels faint.
• Position the patient sitting upright or at 45 degrees.
• Expose the chest appropriately while maintaining dignity.
• Ask for a chaperone if appropriate.

Initial assessment

• Look from the end of the bed.
• Assess whether the patient is comfortable, breathless, cyanosed, pale, sweaty or confused.
• Assess whether the patient can speak in full sentences.
• Look for use of accessory muscles.
• Look for oxygen therapy, nebulisers, inhalers, sputum pot or tissues.
• Look for IV antibiotics or fluids if inpatient.
• If acutely unwell, perform ABCDE assessment and call for senior help.

ABCDE assessment if acutely unwell

• Airway: check whether the patient can speak and whether the airway is patent.
• Breathing: assess respiratory rate, oxygen saturation, work of breathing and auscultate the chest.
• Circulation: assess pulse, blood pressure, capillary refill, skin temperature, ECG monitoring and obtain IV access.
• Disability: assess consciousness level and capillary blood glucose.
• Exposure: check temperature, look for rash, dehydration, DVT signs and sources of infection while maintaining dignity.

Vital signs

• Respiratory rate.
• Oxygen saturation.
• Heart rate.
• Blood pressure.
• Temperature.
• Level of consciousness.
• Capillary blood glucose if diabetic or acutely unwell.
• Pain score if pleuritic chest pain is present.

Hands

• Look for peripheral cyanosis.
• Check capillary refill time.
• Look for finger clubbing.
• Look for nicotine staining.
• Look for palmar pallor.
• Look for tremor from beta-agonist use.
• Look for asterixis if CO2 retention is suspected.
• Assess peripheral temperature.

Pulse and blood pressure

• Assess pulse rate.
• Assess pulse rhythm.
• Tachycardia may suggest fever, sepsis, hypoxia, PE or beta-agonist use.
• Irregular rhythm may suggest atrial fibrillation.
• Measure blood pressure.
• Hypotension is concerning for sepsis, PE or severe illness.

Face, mouth and neck

• Look for central cyanosis.
• Look for conjunctival pallor.
• Look for dehydration such as dry mucous membranes.
• Look for cachexia or weight loss.
• Assess cervical and supraclavicular lymph nodes.
• Check tracheal position.
• Assess jugular venous pressure.

Chest inspection

• Inspect chest shape.
• Look for respiratory distress.
• Look for asymmetrical chest movement.
• Look for scars.
• Look for chest wall deformity.
• Observe respiratory pattern.
• Look for pursed-lip breathing or hyperinflation suggesting COPD.

Palpation

• Assess chest expansion.
• Compare expansion on both sides.
• Reduced expansion on one side may suggest pneumonia, effusion, collapse or pneumothorax.
• Assess tactile vocal fremitus if consolidation or effusion is suspected.
• Palpate for chest wall tenderness.
• Confirm tracheal position.

Percussion

• Percuss symmetrical areas of the chest.
• Dullness may suggest consolidation, collapse or pleural effusion.
• Stony dullness suggests pleural effusion.
• Hyperresonance suggests pneumothorax or hyperinflation.
• Compare side to side.

Auscultation

• Auscultate symmetrical areas of the chest.
• Assess air entry.
• Listen for crackles.
• Listen for bronchial breathing.
• Listen for wheeze.
• Listen for pleural rub.
• Assess vocal resonance if consolidation or effusion is suspected.
• Ask the patient to cough and reassess crackles if secretions are suspected.

Expected findings

• Focal crackles may suggest pneumonia.
• Bronchial breathing suggests consolidation.
• Dullness with increased vocal resonance suggests consolidation.
• Stony dullness with reduced breath sounds suggests pleural effusion.
• Wheeze suggests asthma, COPD or bronchospasm.
• Pleural rub suggests pleurisy or pulmonary embolism.
• Diffuse crackles may suggest pulmonary oedema or widespread infection.

Cardiovascular examination

• Assess JVP.
• Auscultate heart sounds.
• Listen for murmurs.
• Check for peripheral oedema.
• Look for signs of heart failure.
• Heart failure can mimic chest infection with cough and crackles.

Peripheral and systemic examination

• Check calves for unilateral swelling or tenderness if PE is suspected.
• Look for peripheral oedema.
• Assess hydration status.
• Look for skin mottling or poor perfusion in sepsis.
• Assess for lymphadenopathy if TB or malignancy is suspected.
• Consider abdominal examination if aspiration, sepsis source or systemic illness is suspected.

Specific findings to mention in chest infection OSCE

• Fever, tachycardia, tachypnoea and hypoxia suggest significant infection.
• Confusion in an older patient may indicate severe pneumonia or sepsis.
• Focal crackles and bronchial breathing suggest pneumonia.
• Wheeze may indicate asthma or COPD exacerbation.
• Clubbing suggests chronic lung disease, bronchiectasis, malignancy or interstitial lung disease.
• Raised JVP, oedema and basal crackles suggest heart failure.
• Normal chest examination does not exclude early pneumonia or PE.

To complete the examination

To complete my examination, I would review observations, calculate pneumonia severity using CRB65 or CURB65 where appropriate, check oxygen saturation, request chest X-ray, blood tests, sputum culture, blood cultures if severe or septic, and consider ECG, blood gas or CT imaging depending on the clinical picture.

4. Differential Diagnosis

Infective causes

• Acute bronchitis.
• Community-acquired pneumonia.
• Hospital-acquired pneumonia.
• Aspiration pneumonia.
• COPD infective exacerbation.
• Bronchiectasis infective exacerbation.
• Influenza.
• COVID-19 or other viral respiratory infection depending on local epidemiology.
• Tuberculosis.
• Lung abscess.

Non-infective mimics

• Pulmonary embolism.
• Heart failure or pulmonary oedema.
• Asthma exacerbation.
• COPD exacerbation without bacterial infection.
• Pneumothorax.
• Lung cancer.
• Interstitial lung disease exacerbation.
• Aspiration pneumonitis.

Causes of recurrent chest infection

• COPD.
• Bronchiectasis.
• Asthma with mucus plugging.
• Aspiration.
• Immunodeficiency.
• Lung cancer causing bronchial obstruction.
• Foreign body.
• Cystic fibrosis if clinically relevant.

5. Investigations

Bedside tests

• Full observations.
• Oxygen saturation.
• Capillary blood glucose if diabetic or acutely unwell.
• Peak flow if asthma or COPD is suspected and safe.
• Urine dip if dehydration, sepsis or renal involvement is suspected.
• Pregnancy test in women of reproductive age when relevant.
• CRB65 score in community assessment if pneumonia is suspected.

Blood tests

• Full blood count.
• Urea and electrolytes.
• Creatinine and estimated GFR.
• CRP.
• Liver function tests if severe infection or systemic illness is suspected.
• Blood cultures if severe pneumonia, sepsis or hospital admission is likely.
• Venous or arterial blood gas if severe breathlessness, hypoxia, COPD or sepsis is suspected.
• Lactate if sepsis is suspected.

Microbiology

• Sputum culture if productive cough, severe infection, bronchiectasis or failure to improve.
• Blood cultures before antibiotics if sepsis or severe pneumonia is suspected.
• Viral swabs depending on local policy and epidemiology.
• Sputum acid-fast bacilli testing if TB is suspected.
• Urinary pneumococcal or legionella antigen in selected severe pneumonia cases according to local policy.

Imaging

• Chest X-ray if pneumonia is suspected.
• Chest X-ray if symptoms are severe, red flags are present or diagnosis is unclear.
• Repeat chest X-ray may be needed after pneumonia in higher-risk patients, especially smokers or persistent symptoms.
• CT chest if complications, malignancy, abscess, empyema or unclear diagnosis is suspected.
• CT pulmonary angiography if PE is suspected and imaging is indicated.
• Ultrasound chest if pleural effusion or empyema is suspected.

Other investigations

• ECG if chest pain, arrhythmia, sepsis or cardiac mimic is suspected.
• BNP or NT-proBNP if heart failure is suspected.
• Spirometry when stable if COPD or asthma is suspected.
• HIV test if recurrent infection, TB or immunosuppression is suspected and consent is obtained.
• Swallow assessment if aspiration is suspected.

Important investigation points

• Chest X-ray helps distinguish pneumonia from acute bronchitis.
• CRB65 or CURB65 supports severity assessment but does not replace clinical judgement.
• Blood cultures are most useful in severe or hospitalised pneumonia.
• Sputum culture is useful in severe, recurrent or non-responding infection.
• A normal early chest X-ray does not completely exclude pneumonia if clinical suspicion is high.

6. Management

Management depends on severity, likely diagnosis, comorbidities, oxygenation, social support and risk of complications. In an OSCE, separate acute unstable management from community management of mild infection.

Immediate approach if acutely unwell

1. Assess using ABCDE.
2. Call for senior help if severe breathlessness, hypoxia, confusion, hypotension, sepsis features or respiratory failure are present.
3. Sit the patient upright.
4. Give oxygen if hypoxaemic according to local oxygen target protocol.
5. Attach monitoring if unstable.
6. Obtain IV access if clinically indicated.
7. Send blood tests and cultures if severe infection or sepsis is suspected.
8. Start antibiotics according to local antimicrobial guideline if bacterial pneumonia or sepsis is suspected.
9. Give fluids carefully if hypotensive or dehydrated, considering heart failure risk.

Community management of likely acute bronchitis

• Explain that most acute bronchitis is viral and self-limiting.
• Advise rest and adequate fluids.
• Advise simple analgesia or antipyretics if appropriate.
• Avoid routine antibiotics unless bacterial infection, pneumonia or high-risk features are suspected.
• Advise smoking cessation if relevant.
• Provide safety-net advice for worsening symptoms or red flags.

Management of suspected community-acquired pneumonia

• Assess severity using clinical judgement and CRB65 or CURB65 where appropriate.
• Decide place of care: community, same-day assessment, hospital or critical care depending on severity.
• Start antibiotics according to local antimicrobial guideline.
• Check oxygen saturation and give oxygen if hypoxaemic.
• Encourage fluids if safe and appropriate.
• Arrange follow-up and safety-netting if managed in the community.
• Consider admission for hypoxia, confusion, hypotension, high respiratory rate, frailty, significant comorbidity or poor social support.

Management if COPD exacerbation is present

• Use controlled oxygen if at risk of hypercapnic respiratory failure.
• Give bronchodilators according to local protocol.
• Consider steroids and antibiotics according to symptoms and local guidance.
• Check blood gas if severe, drowsy, hypoxic or at risk of CO2 retention.
• Consider non-invasive ventilation if respiratory acidosis persists according to local protocol.
• Review inhaler technique and smoking cessation after stabilisation.

Management if asthma exacerbation is present

• Assess severity using symptoms, oxygen saturation, respiratory rate, pulse and peak flow.
• Give oxygen if hypoxaemic.
• Give inhaled or nebulised bronchodilator according to local protocol.
• Give systemic corticosteroids according to local protocol.
• Escalate urgently if poor response, exhaustion, silent chest, cyanosis or reduced consciousness.
• Review inhaler technique and action plan after stabilisation.

Management if aspiration is suspected

• Assess severity and oxygenation.
• Consider chest X-ray and blood tests.
• Treat aspiration pneumonia with antibiotics according to local guideline if infection is present.
• Assess swallowing safety.
• Refer to speech and language therapy if dysphagia is suspected.
• Address aspiration risk factors such as reduced consciousness, poor dentition or neurological disease.

Follow-up and prevention

• Advise smoking cessation.
• Review vaccination status where appropriate.
• Ensure follow-up if symptoms fail to improve.
• Consider repeat chest imaging after pneumonia in high-risk patients or persistent symptoms.
• Optimise COPD, asthma or bronchiectasis management if present.
• Review inhaler technique and adherence.
• Assess social support and ability to return if worsening.

Safety-net advice

• Seek urgent help for worsening breathlessness.
• Seek urgent help for chest pain.
• Seek urgent help for confusion, collapse or blue lips.
• Seek urgent help for coughing blood.
• Seek review if fever persists or symptoms worsen.
• Seek review if unable to drink fluids or passing very little urine.
• Seek review if symptoms do not improve as expected.

7. Examiner Questions

1. What is the difference between acute bronchitis and pneumonia?
2. What symptoms suggest pneumonia?
3. What red flags would you ask about?
4. What is CRB65?
5. What is CURB65?
6. What observations are important in chest infection?
7. What signs suggest consolidation?
8. What investigations would you request?
9. When would you request a chest X-ray?
10. When would you admit a patient with chest infection?
11. When are antibiotics indicated?
12. What causes recurrent chest infections?
13. What alternative diagnoses can mimic chest infection?
14. What safety-net advice would you give?

Suggested short answers

8. OSCE Pearls

• Start by assessing severity, not by deciding antibiotics.
• Check respiratory rate and oxygen saturation early.
• Confusion in pneumonia is a serious sign, especially in older patients.
• Pleuritic chest pain with breathlessness can be pneumonia or PE.
• Focal crackles and bronchial breathing support pneumonia.
• Diffuse wheeze suggests asthma or COPD exacerbation.
• Rusty sputum may occur in pneumococcal pneumonia.
• Large-volume foul sputum suggests bronchiectasis or aspiration.
• Recurrent pneumonia in the same area raises concern for bronchial obstruction or malignancy.
• TB symptoms are chronic cough, fever, night sweats and weight loss.
• Do not give antibiotics automatically for every cough.
• Use CRB65 or CURB65 with clinical judgement.
• Ask about comorbidities, frailty and social support before deciding community management.
• Always safety-net worsening breathlessness, chest pain, confusion, haemoptysis and dehydration.

9. Example Presentation to Examiner

10. References

• NICE Clinical Knowledge Summary: Chest infections - adult.
• NICE NG250: Pneumonia: diagnosis and management.
• NICE NG237: Suspected acute respiratory infection in over 16s.
• British Thoracic Society Guidelines for community-acquired pneumonia in adults.
• Local antimicrobial, respiratory, sepsis and oxygen therapy protocols.