Diagnosis of Pneumonia in Children

Clinical Signs and Symptoms

• The British Thoracic Society guidelines state that WHO-defined tachypnea has the highest sensitivity (74%) and specificity (67%) for radiologically defined pneumonia in children under 5 years 1, 2, 3
• In a 2-year-old child, a respiratory rate >40 breaths/min is the appropriate threshold for diagnosing pneumonia, as recommended by the British Thoracic Society 1, 4
• A systematic review found that a respiratory rate >50 breaths/min has a positive likelihood ratio of 1.90 (95% CI 1.45-2.48) for diagnosing pneumonia 5
• The American Academy of Pediatrics and the British Thoracic Society note that fever is non-specific and variably present, and must be combined with other signs like recession and tachypnea for diagnostic utility 1, 4, 6
• Cough is a late manifestation of pneumococcal pneumonia and is less sensitive for early pneumonia detection, according to the British Thoracic Society 4
• Difficulty breathing is more helpful in older children (>36 months) rather than in the 2-year-old age group, as stated by the British Thoracic Society 1, 7
• The British Thoracic Society recommends that bacterial pneumonia should be considered in children up to 3 years when there is fever >38.5°C together with chest recession AND respiratory rate >50/min 1, 4, 7
• Admission criteria include respiratory rate >50 breaths/min in older children, confirming its importance as a severity marker, as recommended by the British Thoracic Society 7
• Tachypnea may be less sensitive early in disease (<3 days' duration), according to the British Thoracic Society 1, 2
• Respiratory rate is difficult to count in healthy, restless children but becomes easier in moderately to severely ill children who are quieter, as noted by the British Thoracic Society 1, 4