What are the signs and symptoms of pneumonia?

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Last updated: September 9, 2025View editorial policy

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Signs and Symptoms of Pneumonia

The most common signs and symptoms of pneumonia include cough, dyspnea, pleural pain, fever ≥38°C, tachypnea, and new localizing chest examination signs such as crackles and diminished breath sounds. 1

Common Clinical Manifestations

Respiratory Symptoms

  • Cough: Often the earliest and most common symptom
    • Initially may be dry, then becomes productive
    • Can produce blood-stained sputum in severe cases, particularly in primary viral pneumonia 1
  • Dyspnea (difficulty breathing/breathlessness)
  • Pleural pain: Often sharp and worsens with deep breathing
  • Tachypnea (rapid breathing)
    • Particularly important diagnostic sign in children
    • WHO defined tachypnea: >60 breaths/min in children <2 months, >50 breaths/min in children 2-12 months, and >40 breaths/min in children >12 months 2
    • In infants <1 year, respiratory rate >70 breaths/min suggests severe disease (sensitivity 63%, specificity 89%) 2

Systemic Symptoms

  • Fever ≥38.5°C (especially important in children)
  • Sweating, shivers, aches, and pains including generalized myalgia 1
  • Fatigue
  • Loss of appetite 3

Physical Examination Findings

  • Crackles (rales) on auscultation, especially basal crackles 1
  • Diminished breath sounds over affected area
  • Chest recession (retractions)
  • Bronchial breathing (in lobar pneumonia)
  • Dullness to percussion (with consolidation or pleural effusion)

Age-Specific Presentations

In Children

  • Abdominal pain: May reflect referred pain from the diaphragmatic pleura 2, 1
  • Headache and nausea 3
  • Chest recession and tachypnea are particularly important signs 2
  • Wheezing: Present in about 30% of mycoplasma pneumonias, more common in older children 2

In Elderly

  • Confusion
  • Failure to thrive
  • Worsening of underlying chronic illness
  • Falls
  • May present with fewer respiratory symptoms and more non-specific manifestations 1

Signs of Severe Disease

General Danger Signs

  • Cyanosis
  • Rapid clinical deterioration
  • Severe respiratory distress
  • Hypoxemia (SpO₂ <93%) - critical sign of severe pneumonia 1
  • Inability to drink
  • Vomiting everything
  • Convulsions
  • Lethargy or unconsciousness
  • Severe malnutrition 1

Diagnostic Considerations

  • The absence of runny nose combined with breathlessness, crackles, diminished breath sounds, tachycardia, and fever is highly suggestive of pneumonia 1
  • If all clinical signs (respiratory rate, auscultation, and work of breathing) are negative, chest radiographic findings are unlikely to be positive 2
  • Laboratory findings: C-reactive protein (CRP) ≥30 mg/L increases the likelihood of pneumonia when combined with suggestive symptoms 1

Differentiating Features

  • Bacterial pneumonia: Consider in children up to 3 years when there is fever >38.5°C together with chest recession and respiratory rate >50/min 2
  • Viral or mycoplasmal infection: More likely when wheeze is present 2
  • Pneumonia vs. asthma: Can be confused, especially when wheezing is present 1

The symptoms of pneumonia typically develop over several days, with most patients presenting within 14 days of symptom onset. The median duration of symptoms in children with radiographically confirmed pneumonia is approximately 3 days 2.

References

Guideline

Respiratory Tract Infections and Interstitial Lung Disease

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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