Cough-variant asthma: How to clinch a tough diagnosis

Asthma is one of the most frequent causes of chronic cough. Unlike typical asthma, in which dyspnea and wheezing are major features, cough is the sole or predominant symptom in cough-variant asthma. The diagnosis often presents a challenge, since physical examination and pulmonary function findings may be normal. Although the demonstration of bronchial hyperresponsiveness is consistent with cough-variant asthma, it is not diagnostic. Other conditions that may mimic cough-variant asthma include postviral cough and eosinophilic bronchitis. Most patients with cough-variant asthma respond to inhaled β-agonists alone or combined with inhaled corticosteroids. A subgroup of patients with severe cough-variant asthma may require oral corticosteroids. Recent data suggest that leukotriene receptor antagonists may be particularly effective.