Pneumonia

Physical Examination

• General examination:

  • Fever: Elevated body temperature.

  • Tachypnea: Rapid breathing rate.

  • Tachycardia: Increased heart rate.

  • Cyanosis: Bluish discoloration of the skin.

  • Accessory muscle use: Neck and shoulder muscles during breathing.

• Chest inspection:

  • Asymmetrical expansion: Unequal chest movement.

  • Reduced expansion: Decreased movement on affected side.

• Palpation:

  • Decreased chest expansion: Diminished movement on affected side.

  • Tactile fremitus: Increased tactile fremitus

• Percussion:

  • Dullness: Decreased resonance over consolidation or pleural effusion.

• Auscultation:

  • Crackles: Discontinuous, high-pitched sounds over consolidation areas.

  • Pleural friction rub: Grating sound over pleural inflammation area.

  • Bronchial breath sounds: Harsh, loud breath sounds over consolidation.

  • Increased vocal resonance

Investigations

• Laboratory tests:

  • Complete blood count: Leukocytosis or leukopenia, increased neutrophils, anemia.

  • Blood cultures: Identifying causative pathogens, especially in severe pneumonia.

  • C-reactive protein (CRP) and procalcitonin: Inflammatory markers, may help differentiate bacterial from viral pneumonia.

  • Arterial blood gas (ABG): Assessing oxygenation, ventilation, and acid-base status.

  • Sputum culture and Gram stain: Identifying causative organisms, guiding antibiotic therapy.

  • Urinary antigen tests: Detecting Streptococcus pneumoniae or Legionella pneumophila.

  • Serology: Atypical pathogens (Mycoplasma, Chlamydia, Legionella) or viral infections (influenza, respiratory syncytial virus).

• Imaging:

  • Chest X-ray: Consolidation, interstitial infiltrates, pleural effusion, or cavitation.

  • Chest CT scan: Better visualisation of the lung parenchyma, detecting complications (abscess, empyema).

• Invasive tests:

  • Bronchoscopy: Obtaining bronchoalveolar lavage (BAL) samples, identifying causative organisms, assessing complications (tumor, foreign body).

  • Thoracentesis: Aspiration of pleural fluid for analysis, culture, and cytology in cases of pleural effusion.

• Other tests:

  • Pulmonary function tests: Assessing underlying lung diseases (COPD, asthma).

  • Echocardiography: Assessing cardiac function, valvular diseases, or endocarditis.

  • Tuberculin skin test or interferon-gamma release assay (IGRA): Ruling out tuberculosis.

  • HIV testing: Assessing for an underlying immunodeficiency.

Management

• General management:

  • Oxygen therapy: Maintain adequate oxygen saturation and alleviate hypoxia.

  • Hydration: Adequate fluid intake, prevent dehydration.

  • Nutritional support: Ensure proper nutrition for immune function and recovery.

  • Vaccination: Pneumococcal and influenza vaccines for prevention.

  • Smoking cessation: Encourage patients to quit smoking to reduce the risk of pneumonia and complications.

  • Treat underlying conditions: Optimize management of comorbidities such as COPD, asthma, or heart failure.

  • Home care or hospitalisation: Assess the need for hospitalisation based on severity scores such as CURB-65 or PSI.

  • Physiotherapy: Chest physiotherapy, breathing exercises, and early mobilisation.

• Medical management:

  • Empirical antibiotics: Initiate broad-spectrum antibiotics based on severity and local guidelines.

  • Adjust antibiotics: Narrow or change antibiotic coverage based on culture results and clinical response.

  • Antiviral therapy: Oseltamivir for influenza if indicated.

  • Corticosteroids: Consider for severe community-acquired pneumonia or in patients with refractory septic shock.

  • Analgesics: Pain relief and management of fever.

  • Bronchodilators: If indicated for underlying bronchospasm or airway obstruction.

• Surgical management:

  • Drainage: Percutaneous or surgical drainage of lung abscesses or empyema.

  • Decortication: Removal of fibrous pleural peel in cases of trapped lung due to empyema.

  • Resection: Lung resection for non-resolving pneumonia or complications such as bronchiectasis.

  • Bronchoscopy: Foreign body removal or airway stenting in cases of obstruction.

Severity Assessment

CURB 65

CURB-65 is a clinical prediction rule used to assess the severity of community-acquired pneumonia (CAP) and guide decisions on whether a patient requires hospitalisation.

1. Confusion: New-onset confusion or altered mental status (Abbreviated Mental Test score ≤8)

2. Urea: Blood urea nitrogen (BUN) > 7 mmol/L (19.6 mg/dL).

3. Respiratory rate: ≥ 30 breaths per minute.

4. Blood pressure: Systolic blood pressure < 90 mmHg or diastolic blood pressure ≤ 60 mmHg.

5. Age: ≥ 65 years old.

The total score ranges from 0 to 5 points. The management approach based on the CURB-65 score is as follows:

• Score 0-1: Low risk, consider outpatient treatment.

• Score 2: Moderate risk; consider hospitalization or close monitoring.

• Score 3-5: High risk, hospitalise with possible consideration for intensive care unit (ICU) admission.

PSI (Pneumonia Severity Index Score)

The Pneumonia Severity Index (PSI) is a clinical prediction rule used to assess the severity of community-acquired pneumonia (CAP) and guide decisions on whether a patient requires hospitalisation or can be managed as an outpatient. The PSI score is based on patient demographics, comorbidities, physical examination findings, and laboratory and radiographic results. The score stratifies patients into five risk classes (I-V) based on the calculated score.

The PSI consists of three main categories:

1. Demographics:

   • Age (points vary by sex: men receive their age in points, while women receive their age minus 10 points).

   • Nursing home resident (+10 points).

2. Comorbidities:

   • Neoplastic disease (+30 points).

   • Liver disease (+20 points).

   • Congestive heart failure (+10 points).

   • Cerebrovascular disease (+10 points).

   • Renal disease (+10 points).

3. Physical examination, laboratory, and radiographic findings:

   • Altered mental status (+20 points).

   • Respiratory rate ≥ 30 breaths per minute (+20 points).

   • Systolic blood pressure < 90 mmHg (+20 points).

   • Temperature < 35°C or ≥ 40°C (+15 points).

   • Pulse rate ≥ 125 beats per minute (+10 points).

   • Arterial pH < 7.35 (+30 points).

   • Blood urea nitrogen (BUN) ≥ 11 mmol/L (30 mg/dL) (+20 points).

   • Sodium < 130 mmol/L (+20 points).

   • Glucose ≥ 14 mmol/L (250 mg/dL) (+10 points).

   • Hematocrit < 30% (+10 points).

   • Partial pressure of oxygen (PaO2) < 60 mmHg or oxygen saturation < 90% (+10 points).

   • Pleural effusion on radiography (+10 points).

Based on the total PSI score, patients are classified into five risk classes:

• Class I: Score ≤ 50 points.

• Class II: Score 51-70 points.

• Class III: Score 71-90 points.

• Class IV: Score 91-130 points.

• Class V: Score > 130 points.

The management approach based on the PSI risk class is as follows:

• Classes I-II: Low risk, consider outpatient treatment.

• Class III: Moderate risk, consider observation or short hospital stay.

• Classes IV-V: High risk, hospitalise with possible consideration for intensive care unit (ICU) admission.

The PSI score helps clinicians make more objective decisions about the appropriate level of care for patients with community-acquired pneumonia, ensuring that they receive the most suitable treatment while optimising healthcare resources.

Complications of Pneumonia

Respiratory complications:

• Pleural effusion

• Empyema

• Lung abscess

• Pneumothorax

• Respiratory failure

• Acute respiratory distress syndrome (ARDS)

• Bronchiectasis

Non-respiratory complications:

• Sepsis

• Bacteremia

• Pericarditis

• Endocarditis

• Meningitis

• Joint infections

• Kidney dysfunction

• Disseminated intravascular coagulation (DIC)