How should a 4-year-old girl with a one-month persistent cough be evaluated and managed?

Management of a 4-Year-Old with One-Month Cough

This child has reached the threshold for chronic cough (≥4 weeks) and requires systematic evaluation with chest radiograph and classification of cough type (wet versus dry) to guide management—not empirical treatment or watchful waiting. 1

Immediate Assessment

Critical Red Flags to Rule Out First

• Check respiratory rate (>50 breaths/min indicates distress), oxygen saturation (<92% requires urgent intervention), and work of breathing (accessory muscle use, grunting) 2
• Ask about sudden onset with choking episode suggesting foreign body aspiration, especially if accompanied by unilateral wheeze or asymmetric breath sounds 2
• Evaluate for pertussis if cough is paroxysmal with post-tussive vomiting or inspiratory "whoop," particularly if vaccination incomplete 3, 2
• Assess for pneumonia indicators: high fever ≥39°C, tachypnea, hypoxia, or focal crackles on auscultation 2

Cough Characterization

The single most important clinical distinction is whether the cough is wet/productive versus dry. 1, 3

• Wet cough sounds loose, rattling, or "chesty" and suggests airway secretions 2
• Dry cough is non-productive without audible secretions 3

Mandatory Initial Investigations at 4 Weeks

Required Testing

• Obtain chest radiograph to detect structural abnormalities, pneumonia, foreign body, or early bronchiectasis 1, 3
• Spirometry is not feasible at age 4 (most children cannot reliably perform until age 6-7 years), so defer this test 1, 2
• Detailed history focusing on: coughing with feeding (aspiration), failure to thrive, digital clubbing, recurrent infections, family history of atopy or cystic fibrosis 2

Management Algorithm Based on Cough Type

If Wet/Productive Cough: Protracted Bacterial Bronchitis

Initiate a 2-week course of amoxicillin or amoxicillin-clavulanate targeting common respiratory bacteria (Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis). 3, 2

• If cough resolves after 2 weeks: diagnosis of protracted bacterial bronchitis confirmed; no further workup needed 2
• If wet cough persists after 2 weeks: extend antibiotics for an additional 2 weeks 2
• If wet cough persists after 4 weeks total antibiotics: refer to pediatric pulmonology for bronchoscopy, chest CT, immunologic evaluation, and assessment for bronchiectasis, aspiration syndromes, cystic fibrosis, or primary ciliary dyskinesia 2

Evidence strength: Protracted bacterial bronchitis accounts for 23-41% of chronic cough in prospective pediatric cohorts and responds well to antibiotics. 2

If Dry/Non-Productive Cough: Watchful Waiting

Continue observation without medication; most dry coughs resolve spontaneously. 3, 2

Do NOT Diagnose Asthma Based on Cough Alone

• Asthma requires additional features beyond isolated cough: recurrent wheeze, nocturnal symptoms, exercise intolerance, or family history of atopy 3, 2
• Chronic isolated cough lacks asthma-related airway inflammation in the majority of children 2
• Do not prescribe empirical asthma medications (bronchodilators, inhaled corticosteroids) unless spirometry demonstrates reversible obstruction or clear wheeze is present on examination 3, 2

Common pitfall: Over-diagnosing asthma in children with isolated dry cough is a well-documented error in pediatric practice. 2

What NOT to Do

• Do not use over-the-counter cough medicines (dextromethorphan, antihistamines, decongestants) in children under 6 years—they lack efficacy and carry risk of serious adverse events including fatalities 4
• Do not prescribe codeine—it is contraindicated in children due to risk of severe respiratory depression 2
• Do not empirically treat for gastroesophageal reflux or upper airway cough syndrome unless specific clinical features support these diagnoses; they are uncommon causes in prospective pediatric studies 3, 2
• Do not dismiss as "post-viral cough" without proper evaluation—serious underlying conditions (bronchiectasis, aspiration, cystic fibrosis) are documented in 18-30% of children with chronic cough 1

Supportive Care Measures

• Eliminate environmental tobacco smoke exposure—this worsens respiratory symptoms and impairs secretion clearance 3, 2
• Ensure adequate hydration to thin secretions 3, 2
• Acetaminophen for fever/discomfort according to weight-based dosing 3
• Elevate head of bed during sleep to improve comfort 2

Follow-Up Strategy

• Re-evaluate in 2-4 weeks to assess response to treatment (if antibiotics given) or spontaneous resolution (if dry cough) 3, 2
• Immediate return if: respiratory distress develops, new high fever appears, oxygen saturation drops, inability to feed, or cough becomes paroxysmal with vomiting 3, 2
• Refer to pediatric pulmonology if: wet cough unresponsive to 4 weeks antibiotics, failure to thrive, digital clubbing, hemoptysis, or diagnostic uncertainty after appropriate workup 2

Parent Education

• Explain that chronic cough at 4 weeks requires evaluation to rule out serious conditions, not just reassurance 1
• If wet cough with antibiotics prescribed, emphasize completing the full 2-week course even if improvement occurs earlier 2
• If dry cough with watchful waiting, provide clear warning signs requiring immediate return and expected timeline for spontaneous resolution 3, 2
• Address parental anxiety directly—explain that absence of immediate medication does not indicate inadequate care when the evidence-based approach is observation 2