Malignant cough equivalent asthma: Definition and case reports

Background: Cough equivalent asthma is a cause for chronic cough and usually responds to corticosteroid therapy. Oral corticosteroids are employed in a diagnostic-therapeutic trial and inhaled corticosteroids are employed in maintenance therapy. In certain cases the cough may be especially severe and require escalated doses of oral corticosteroids for initial control. This is labeled malignant cough equivalent asthma. Objective: To define malignant cough equivalent asthma, provide two case reports, and identify features that should alert physicians to consider the possibility of malignant cough equivalent asthma. Case Reports: We report two patients who presented complaining of chronic cough that was disruptive of sleep and normal activities, and in one patient prompted an emergency room visit and later hospitalization. The patients underwent evaluation with history, physical examination, and laboratory testing as indicated. Other causes for chronic cough were ruled out by appropriate testing, or were treated, and patients did not respond to usual corticosteroid treatment for cough equivalent asthma. These patients were considered to have a more severe form of cough equivalent asthma and did respond to treatment with higher doses of oral corticosteroids. Conclusion: Malignant cough equivalent asthma is a cause of chronic cough that is disruptive to sleep or normal activities, may lead to emergency room visits or hospitalization, and requires escalated doses of oral corticosteroids for initial control.