Do pediatric patients with mild asthma typically present with a dry frequent cough?

Dry Frequent Cough in Children with Mild Asthma

While children with asthma can present with a dry frequent cough, the majority of children with isolated dry cough do not have asthma, and cough alone should not be used to diagnose asthma in pediatric patients. 1

Key Clinical Principle

Asthma guidelines explicitly caution against diagnosing asthma based on cough alone because while almost all children with asthma have intermittent cough, only about a quarter of children with these symptoms actually have asthma. 1 This represents one of the most important pitfalls in pediatric respiratory medicine—the over-diagnosis of asthma in children presenting with isolated cough. 1, 2

When Asthma Does Present with Cough

When children with asthma do present with cough as a symptom:

• The cough associated with asthma without coexistent respiratory infection is typically dry 1
• Cough is usually accompanied by other features such as recurrent wheeze, breathlessness, or exercise-induced symptoms 1
• The sensitivity and specificity of cough as a marker for wheeze in asthma is poor at only 34% and 35%, respectively 1

Critical Evidence Against "Cough Variant Asthma"

Studies examining airway profiles in children with isolated chronic cough have shown very few children with airway inflammation consistent with asthma. 1 Specifically:

• A cross-sectional community study of 1,178 children concluded that "cough variant asthma is probably a misnomer for most children in the community who have persistent cough" 1
• Research has concluded that "chronic cough is not associated with the cell profiles suggestive of asthma and in isolation should not be treated with prophylactic anti-asthma drugs" 1
• Community studies found that "persistent cough and recurrent chest colds without wheeze should not be considered a variant of asthma" 1

Diagnostic Approach for Isolated Dry Cough

Do not prescribe asthma medications unless other features of asthma are present, such as recurrent wheeze or dyspnea. 3 The appropriate evaluation includes:

• Minimum workup: chest radiograph and spirometry (if age appropriate) to rule out serious pathology 1
• Look for specific diagnostic indicators beyond cough, including wheeze, exercise intolerance, or nocturnal symptoms 1, 4
• Consider that most viral-associated coughs resolve within 7-10 days, with 90% of children cough-free by day 21 3

Common Clinical Pitfalls

The most significant error in pediatric practice is over-diagnosing asthma based on the symptom of cough alone. 1, 2 This leads to:

• Inappropriate use of asthma medications in children who do not have asthma 1
• Missing alternative diagnoses such as protracted bacterial bronchitis, post-viral cough, or increased cough receptor sensitivity 1, 3
• Unnecessary long-term controller therapy in children whose cough will resolve spontaneously 3, 2

Alternative Diagnoses to Consider

In children presenting with isolated dry frequent cough:

• Post-viral cough or increased cough receptor sensitivity is the most common etiology in nonspecific cough 1
• Pertussis should be considered if cough becomes paroxysmal with post-tussive vomiting, especially with incomplete vaccination 3
• Upper airway disorders including rhinitis or adenoid hypertrophy may contribute 1
• If cough persists beyond 4 weeks and becomes wet/productive, consider protracted bacterial bronchitis requiring antibiotic therapy 3, 4

When to Consider Asthma Treatment

Only trial asthma medications when:

• Dry cough is associated with documented wheeze, exercise intolerance, or nocturnal symptoms 4
• Spirometry demonstrates reversible airflow obstruction (in age-appropriate children) 1
• There is a clear-cut response to therapeutic trial with relapse on stopping and second response to recommencing 2