What is the treatment for eosinophilic bronchitis?

Treatment for Eosinophilic Bronchitis

Inhaled corticosteroids are the first-line treatment for eosinophilic bronchitis, with allergen avoidance being the primary approach when a specific allergen or occupational sensitizer is identified. 1

Treatment Algorithm

First-Line Therapy

1. Identify and address potential triggers:

   • Consider occupational exposures as potential causes 1
   • If a causal allergen or occupational sensitizer is identified, avoidance is the best treatment 1

2. Inhaled corticosteroids (ICS):

   • Start with medium-dose ICS (e.g., budesonide 400 μg twice daily) 1
   • Treatment typically leads to:
     • Symptomatic improvement
     • Significant reduction in sputum eosinophil count
     • Improvement in cough sensitivity 1

For Persistent or Severe Symptoms

• Increase to high-dose inhaled corticosteroids if symptoms persist 1
• Add oral corticosteroids if symptoms remain troublesome or eosinophilic airway inflammation progresses despite high-dose ICS 1
  • Expert opinion suggests prednisolone 30 mg/day for 2 weeks for diagnostic confirmation 1

Evidence Quality and Considerations

The recommendation for inhaled corticosteroids as first-line therapy is supported by clinical evidence showing:

• Significant improvement in cough symptoms
• Reduction in sputum eosinophil counts
• Normalization of cough sensitivity 1

Studies have demonstrated that budesonide 400 μg twice daily for 4 weeks improves cough with a positive correlation between treatment-induced changes in cough sensitivity and sputum eosinophil count 1.

Duration of Treatment and Monitoring

• The optimal duration of therapy remains undefined 1
• Consider the possibility of airway remodeling (thickened basement membrane) when determining treatment duration 1
• Long-term follow-up suggests that eosinophilic bronchitis may:
  • Be self-limiting in some cases
  • Lead to persistent symptoms requiring ongoing treatment in others (66% of patients)
  • Rarely progress to asthma (9% of patients) or fixed airflow obstruction (16%) 1

Important Caveats

• There is insufficient evidence to guide the specific choice of inhaled corticosteroid, optimal dose, or treatment duration 1
• Consider alternative diagnoses if there is no response to a trial of oral corticosteroids 1
• The role of other potential therapeutic agents such as antihistamines and leukotriene receptor antagonists in eosinophilic bronchitis requires further investigation 1
• Fluticasone has been shown to be more effective than montelukast in reducing sputum eosinophilia in steroid-naive eosinophilic airway inflammation 2

Diagnostic Confirmation

For proper treatment, confirm the diagnosis through:

• Normal spirometry and no evidence of variable airflow obstruction
• Presence of airway eosinophilia (>3% in induced sputum)
• Improvement in cough following corticosteroid therapy 1