What are the signs and symptoms of pneumonia?

Signs and Symptoms of Pneumonia

Pneumonia presents with a combination of respiratory symptoms including cough, dyspnea, pleural pain, fever ≥38°C, tachypnea, and new localizing chest examination signs such as crackles and diminished breath sounds. 1

Core Clinical Presentation

Respiratory Symptoms

• Cough - Primary symptom, often productive 1
• Dyspnea (shortness of breath) - Common and suggestive of pneumonia 1
• Pleural pain - Sharp chest pain that worsens with breathing 1
• Tachypnea (rapid breathing) - Important sign, especially in severe cases 1
• New and localizing chest examination signs - Particularly crackles, diminished breath sounds 1

Systemic Symptoms

• Fever ≥38°C - Common but not universal 1
• Sweating, fevers, or shivers - Often accompanies fever 1
• Aches and pains - Generalized myalgia 1
• Fatigue - Common systemic symptom 2
• Loss of appetite - Frequently reported 2

Age-Specific Presentations

Children

• May present with headache, nausea, and abdominal pain 2
• Tachypnea is a particularly important sign in pediatric pneumonia 1
• Chest indrawing is a significant indicator of severity in children 1
• Hypoxemia (SpO₂ <93%) is a critical sign of severe pneumonia 1

Elderly

• May present with altered mental status rather than typical respiratory symptoms 2
• Often have fewer or atypical symptoms 2
• Absence of fever is more common despite active infection 3

Organism-Specific Presentations

Mycoplasma Pneumoniae

• Particularly common in school-aged children and adolescents 4
• Classic presentation includes fever, arthralgia, headache, cough, and crackles 4
• Wheeze is present in approximately 30% of cases, more common in older children 4
• Often mimics viral respiratory syndromes or asthma 4
• Absence of bronchial breathing and pleural effusion at onset is typical 4

Diagnostic Indicators

Physical Examination Findings

• Tachycardia - Common finding associated with infection and fever 1
• Crackles on auscultation - Highly suggestive of pneumonia 1
• Diminished breath sounds - May indicate consolidation 1
• Dullness to percussion - Suggests consolidation or pleural effusion 1
• Signs of severe respiratory distress - Head nodding, nasal flaring, grunting, stridor, tracheal tugging, intercostal retractions, pronounced lower chest wall indrawing 1

Laboratory and Imaging

• C-reactive protein (CRP) ≥30 mg/L increases likelihood of pneumonia when combined with suggestive symptoms 1
• Chest radiography is recommended to improve diagnostic accuracy when pneumonia is suspected 1
• Leukocytosis (>10,000/μL) or leukopenia (<4,000/μL) may be present 3

Severity Indicators

• Hypoxemia (SpO₂ <93%) - Critical indicator of severe pneumonia 1
• General danger signs - Inability to drink, vomiting everything, convulsions, lethargy or unconsciousness, severe malnutrition 1
• Severe respiratory distress - Includes head nodding, persistent nasal flaring, grunting, stridor while calm, tracheal tugging, intercostal retractions 1

Clinical Pearls

• The absence of runny nose combined with presence of breathlessness, crackles, diminished breath sounds, tachycardia, and fever is highly suggestive of pneumonia 1
• Acute cough (<3 weeks) is less likely to be pneumonia when CRP is <10 mg/L or between 10-50 mg/L in the absence of dyspnea and daily fever 1
• Pneumonia can be confused with asthma, especially when wheezing is present 4
• Abdominal pain in children may be due to referred pain from the diaphragmatic pleura 4

Remember that pneumonia diagnosis requires a combination of symptoms, signs, and ideally radiographic confirmation, as no single clinical feature has sufficient diagnostic accuracy alone 1.