[Management of chronic cough]

Area of Science:

• Pulmonology
• Allergy and Immunology
• Gastroenterology

Context:

• Chronic cough (lasting >8 weeks) is a common and challenging clinical problem.
• Traditional diagnostic algorithms (e.g., Irwin's) have limitations in clinical practice.
• Recent approaches emphasize non-specific cough hyperreactivity.

Purpose:

• To review diagnostic challenges and treatment strategies for chronic cough.
• To highlight limitations of existing diagnostic algorithms.
• To discuss effective interventions and future research directions.

Summary:

• The diagnosis of chronic cough has evolved, with initial algorithms focusing on asthma, chronic rhino-sinusitis, and gastroesophageal reflux, later including eosinophilic bronchitis.
• Current understanding suggests non-specific cough hyperreactivity plays a key role, with other factors potentially modulating it.
• Quantitative assessment using tools like visual analogue scales or quality of life questionnaires is recommended for severe or persistent cough.
• Definitive treatments include smoking cessation and discontinuing ACE inhibitors. Inhaled steroids are effective for eosinophilic cough (identified by sputum eosinophilia or elevated exhaled nitric oxide).
• For refractory chronic cough, antitussive agents are considered, though codeine shows limited efficacy, necessitating research into novel agents.

Impact:

• Provides a concise overview of chronic cough diagnosis and management.
• Highlights the importance of updated diagnostic approaches and quantitative assessment.
• Emphasizes evidence-based treatments and identifies areas for future therapeutic development.