What is the best course of treatment for a 10-year-old patient with a persistent cough?

Management of Persistent Cough in a 10-Year-Old Child

For a 10-year-old with persistent cough, obtain a chest radiograph and spirometry immediately, then follow a systematic algorithm based on whether the cough is wet/productive versus dry, rather than empirically treating for asthma or other conditions without specific supporting features. 1, 2

Initial Assessment and Classification

The first critical step is determining the duration and characteristics of the cough:

• If cough duration is ≥4 weeks, this is classified as "chronic cough" and requires mandatory systematic evaluation rather than watchful waiting 1, 2
• Distinguish wet/productive cough from dry cough, as management pathways differ significantly 1, 3
• Assess for "specific cough pointers" that indicate serious underlying disease: coughing with feeding, digital clubbing, chest deformity, failure to thrive, hemoptysis, or respiratory distress 1, 2

Mandatory Initial Investigations

All children with cough lasting ≥4 weeks require:

• Chest radiograph to identify structural abnormalities, pneumonia, or foreign body 2, 3, 4
• Spirometry (pre- and post-β2 agonist) since this child is 10 years old and can reliably perform the test 2, 3
• Assessment of cough impact on the child and family's quality of life 2, 3

Management Based on Cough Characteristics

For Wet/Productive Cough Without Specific Pointers

Prescribe a 2-week course of antibiotics targeting common respiratory bacteria (Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis), as this likely represents protracted bacterial bronchitis 1, 2, 3:

• First-line choice: Amoxicillin or amoxicillin-clavulanate for children under 5 years 1, 2
• If cough persists after initial 2-week course, add another 2 weeks of antibiotics 3, 5
• If cough persists after 4 weeks total of antibiotics, proceed to flexible bronchoscopy with quantitative cultures and consider chest CT imaging 3

For Dry Cough

Do NOT empirically treat for asthma based on cough alone 1, 2, 3:

• The 2020 CHEST guideline emphasizes that "most children with isolated cough do not have asthma" and that "chronic cough is not associated with cell profiles suggestive of asthma" 1
• Cough sensitivity and specificity for wheeze is poor at only 34% and 35%, respectively 1
• Only consider asthma if other features are present: recurrent wheeze, dyspnea responsive to bronchodilators, or documented airway hyperresponsiveness 1, 2

If asthma is clinically suspected, consider testing for airway hyperresponsiveness in children >6 years 3

Critical Differential: Pertussis

Evaluate for pertussis if the child has 1, 3, 5:

• Paroxysmal cough with post-tussive vomiting
• Inspiratory "whoop" sound
• Cough lasting ≥2 weeks without another apparent cause

If pertussis is suspected:

• Order nasopharyngeal aspirate or swab for culture confirmation 1
• Antibiotics are most effective when given early in the disease (cataral phase) 5
• Be aware that median cough duration is 29-39 days in vaccinated children and 52-61 days in unvaccinated children 3

What NOT to Do: Common Pitfalls

Avoid these inappropriate interventions that lack evidence and may cause harm:

• Do NOT use over-the-counter cough and cold medications in children, as they lack proven efficacy and have potential for serious toxicity 2, 6
• Do NOT empirically treat for upper airway cough syndrome, gastroesophageal reflux, or asthma unless specific clinical features support these diagnoses 1, 2, 3
• Do NOT diagnose asthma based on cough alone without other supporting evidence 1, 2
• Do NOT use β-agonists for acute viral cough, as they are non-beneficial and have adverse events 2
• Do NOT use antihistamines for acute cough, as studies show no significant improvement 2

Environmental and Supportive Measures

Immediately address modifiable factors:

• Identify and eliminate environmental tobacco smoke exposure and other environmental irritants 2, 3, 5
• Ensure adequate hydration to help thin secretions 2
• Teach proper cough technique: deep inhalation before coughing to maximize lung volume and generate adequate expiratory force 2

Follow-Up and Escalation

If empirical treatment is attempted, limit its duration to 2-4 weeks maximum to confirm or refute the diagnosis 2

Expected timeline for resolution:

• Most post-viral coughs resolve within 1-3 weeks 2, 3
• 10% of children may cough for >20-25 days after viral infection 2, 3

Red flags requiring urgent evaluation 2, 3:

• Respiratory rate >50 breaths/min
• Difficulty breathing, grunting, or cyanosis
• Oxygen saturation <92%
• Not feeding well or signs of dehydration
• Persistent high fever ≥39°C for 3+ consecutive days