The Clinical Evaluation of Chronic Cough

The most important factor in evaluating patients with chronic cough is the clinician's assessment. This can either suggest the diagnosis or direct investigations as needed. All patients with chronic cough should have a chest radiograph as well as a spirometric examination. The common causes of cough not associated with obvious respiratory disease include asthma and related syndromes, gastro-oesophageal reflux and Post Nasal Drip syndrome. Specialised investigations which may help to establish the diagnosis include broncho-provocation testing, induced sputum cytology, oesophageal manometry, 24-hour oesophageal pH monitoring, computed tomography (CT) and fiberoptic bronchoscopy. Systematic protocols with high diagnostic yields have been described to assess chronic cough. However if there is no ready access to investigations, therapeutic trials targeting the likely cause of cough are justified.