Pulmonary disease Pneumonia in children

Pneumonia is one of the most common and serious respiratory infections in children worldwide. It is defined as an inflammation of the lung parenchyma, usually caused by infectious agents. Viruses are the most frequent cause of pneumonia in young children, especially those under five years old, with respiratory syncytial virus (RSV), influenza, parainfluenza, and adenovirus being the most common. Bacterial pneumonia is often more severe and is usually caused by Streptococcus pneumoniae or Haemophilus influenzae. In neonates, pathogens such as Group B Streptococcus and E. coli may also be responsible. Risk factors for pediatric pneumonia include prematurity, malnutrition, congenital heart disease, immunodeficiency, and exposure to indoor smoke. Clinical presentation varies with age and etiology, but typical symptoms include fever, cough, tachypnea, and respiratory distress. Chest indrawing, nasal flaring, and grunting are signs of severe disease, while in infants, nonspecific features such as poor feeding, irritability, or lethargy may also occur.