Overview

Definition:
-Bronchiectasis is a chronic lung disease characterized by irreversible dilatation of bronchi and bronchioles, resulting from destruction of bronchial wall cartilage, elastic tissue, and smooth muscle
-In children, it represents a persistent, pathological widening of airways, often leading to chronic cough, sputum production, and recurrent infections.
Epidemiology:
-The incidence and prevalence of bronchiectasis in children vary globally, with higher rates in low-income countries due to increased prevalence of severe childhood infections like pneumonia and tuberculosis
-Specific etiologies like cystic fibrosis, primary ciliary dyskinesia (PCD), and primary immunodeficiencies (PIDs) contribute significantly to its burden
-Post-infectious causes, particularly following adenoviral or pertussis infections, are also common.
Clinical Significance:
-Pediatric bronchiectasis is a serious condition impacting lung function and quality of life
-Early diagnosis and effective management are crucial to prevent progressive lung damage, reduce exacerbations, and improve long-term outcomes
-Understanding its diverse etiologies is paramount for targeted treatment and genetic counseling, vital for DNB and NEET SS preparation in pediatric respiratory medicine.

Etiologies

Infectious Causes:
-Common infectious causes include severe or recurrent pneumonia (bacterial or viral, e.g., adenovirus, pertussis), tuberculosis, and measles
-Post-infectious bronchiectasis is a significant entity, where a severe initial insult leads to airway damage and subsequent colonization.
Cystic Fibrosis Cf:
-Cystic fibrosis is the most common inherited cause of bronchiectasis in children
-Genetic mutations in the CFTR gene lead to thick, viscous mucus production, airway obstruction, chronic infection, and inflammation, ultimately causing bronchiectasis.
Primary Ciliary Dyskinesia Pcd:
-PCD is a group of autosomal recessive disorders affecting motile cilia function
-Impaired mucociliary clearance leads to chronic airway infections, sinusitis, otitis media, and situs inversus in some cases, frequently resulting in bronchiectasis.
Primary Immunodeficiencies Pids: Conditions like Common Variable Immunodeficiency (CVID), X-linked agammaglobulinemia (XLA), and Selective IgA deficiency impair the immune system, making children susceptible to recurrent sinopulmonary infections and subsequent bronchiectasis.
Other Causes: Less common causes include congenital anomalies (e.g., tracheobronchomegaly), foreign body aspiration, allergic bronchopulmonary aspergillosis (ABPA), connective tissue disorders, and gastroesophageal reflux disease (GERD) with aspiration.

Clinical Presentation

Symptoms:
-Chronic daily cough, often productive of purulent sputum, especially in the morning
-Recurrent lower respiratory tract infections (pneumonia, bronchitis)
-Wheezing
-Dyspnea
-Hemoptysis (less common in children)
-Failure to thrive or poor weight gain
-Sinusitis and otitis media are common comorbidities.
Signs:
-Crackles on lung auscultation, particularly at the lung bases
-Clubbing of fingers (in severe or long-standing cases)
-Signs of chronic respiratory distress
-Possible extrapulmonary manifestations depending on etiology (e.g., nasal polyps in CF or PCD).
Diagnostic Criteria: Diagnosis is primarily based on clinical symptoms and confirmation by high-resolution computed tomography (HRCT) of the chest, which demonstrates thickened bronchial walls, peribronchial thickening, and irreversible bronchial dilatation (CT index >1.5 or presence of airways larger than adjacent pulmonary arteries).

Diagnostic Approach

History Taking:
-Detailed birth history (prematurity, meconium aspiration)
-History of severe childhood infections (pertussis, measles, pneumonia)
-Family history of lung disease, CF, PID, or PCD
-Presence of extra-pulmonary symptoms (sinusitis, otitis, diarrhea)
-Immunization status
-Environmental exposures.
Physical Examination:
-Complete respiratory system examination focusing on auscultation for crackles and wheezes
-Assess for clubbing and signs of respiratory distress
-Examine ears and sinuses for signs of chronic infection
-Assess growth parameters.
Investigations:
-HRCT chest is the gold standard for diagnosis and assessment of severity
-Sputum culture and sensitivity (if productive) for microbiology
-Pulmonary function tests (PFTs) may be useful in older children to assess airflow limitation and reversibility
-Sweat chloride test for CF
-Immunoglobulin levels (IgG, IgA, IgM) and lymphocyte subsets for PIDs
-Ciliary beat frequency analysis or genetic testing for PCD
-Allergy testing for ABPA
-pH-impedance studies for GERD.
Differential Diagnosis: Asthma, chronic bronchitis, cystic fibrosis (if initial workup is negative), recurrent pneumonia, tuberculosis, foreign body aspiration, allergic bronchopulmonary aspergillosis, immunodeficiency disorders.

Management

Airway Clearance Techniques:
-The cornerstone of management, aiming to mobilize and clear secretions
-Techniques include: Chest physiotherapy (CPT) - percussion, postural drainage, vibration
-Positive expiratory pressure (PEP) therapy - e.g., Flutter valve, Acapella device
-Autogenic drainage
-Active Cycle of Breathing Techniques (ACBT)
-High-frequency chest wall oscillation (HFCWO).
Pharmacological Treatment:
-Antibiotics: For acute exacerbations (oral or intravenous, guided by culture and sensitivity)
-Prophylactic antibiotics may be used in select cases
-Bronchodilators: May be used if there is a component of reversible bronchoconstriction
-Mucolytics: Such as nebulized hypertonic saline or recombinant human DNase (especially in CF)
-Anti-inflammatory agents: Corticosteroids may be used in specific situations (e.g., ABPA).
Management Of Exacerbations:
-Prompt treatment with antibiotics, enhanced airway clearance, and often bronchodilators
-Hospitalization may be required for severe exacerbations, IV antibiotics, and respiratory support
-Nutritional support is crucial.
Surgical Management:
-Rarely indicated in pediatric bronchiectasis
-Surgical resection of a localized, non-resolving area of bronchiectasis may be considered if there is a clear focal cause (e.g., retained foreign body) or for recurrent life-threatening hemoptysis from a specific segment.
Supportive Care:
-Nutritional support is vital for growth and immune function
-Pneumococcal and influenza vaccinations are recommended
-Education of parents/caregivers on airway clearance techniques and recognizing signs of exacerbation is essential
-Psychosocial support.

Key Points

Exam Focus:
-Recognizing the diverse etiologies of bronchiectasis in children, differentiating them based on clinical presentation and initial investigations, and understanding the principles of airway clearance
-HRCT is diagnostic
-CF, PCD, and PIDs are critical differential diagnoses to rule out.
Clinical Pearls:
-In a child with chronic cough and recurrent chest infections, always consider bronchiectasis
-Thorough history taking focusing on infections, family history, and associated symptoms is crucial
-Partner with respiratory therapists for effective airway clearance strategies
-Regular follow-up is key to monitor progression and adjust management.
Common Mistakes:
-Misdiagnosing bronchiectasis as simple asthma or recurrent pneumonia
-Inadequate or inconsistent application of airway clearance techniques
-Failing to investigate for underlying etiologies like CF or PIDs
-Delaying antibiotic treatment for exacerbations.