Asthma (Pediatric)

Definition

Pediatric asthma is a chronic inflammatory disorder of the airways in children, characterized by reversible airflow obstruction, bronchial hyperresponsiveness, and recurrent episodes of wheezing, coughing, and shortness of breath.

Epidemiology

• Most common chronic respiratory disease in children worldwide
• Prevalence varies between 5–20% depending on region
• More common in boys during childhood; equalizes in adolescence
• Increased prevalence in urban areas and with environmental exposures
• Family history of atopy or asthma increases risk

Etiology

• Genetic predisposition: family history of asthma or atopy
• Environmental triggers: allergens (dust mites, pollen, pet dander), air pollution, tobacco smoke
• Respiratory infections (viral URIs) as triggers or risk factors
• Exercise-induced bronchoconstriction
• Medications (NSAIDs, beta-blockers) can exacerbate symptoms
• Comorbidities: allergic rhinitis, eczema

Pathophysiology

• Chronic airway inflammation with eosinophilic infiltration
• Bronchial hyperresponsiveness leading to airway narrowing
• Mucus hypersecretion and edema of airway walls
• Smooth muscle hypertrophy and bronchoconstriction
• Reversible airflow obstruction causing wheezing and dyspnea
• Airway remodeling in chronic or poorly controlled cases