[Management of chronic cough]

Chronic cough, defined as lasting more than 8 weeks, is a frequent and difficult problem. Since 1981, the north American group of Irwin and coworkers has proposed a diagnostic algorithm with chronic cough being explained in a vast majority of cases by three possible diagnoses: asthma, chronic rhino-sinusitis and gastrooesophageal reflux. This algorithm has been amended in order to include eosinophilic bronchitis and has further been severely criticized because of frequent failure in clinical practice. In 2008, Pavord and Chung have proposed to put the emphasis in chronic cough on non specific cough hyperreactivity, with the aetiological factors suggested by the Irwin group acting at most as modulating agents. Severe or persistent chronic cough should be quantitatively assessed, using for instance a visual analogue scale or a cough specific quality of life questionnaire. Where treatment for chronic cough is concerned, the sole definitely effective interventions are smoking cessation and discontinuation of a converting enzyme inhibitor. Long term inhaled steroids are also effective in case of eosinophilic cough (defined on basis of eosinophilia in induced sputum or increased level of exhaled NO). In case of chronic cough unresponsive to the hereinabove described management, an antitussive agent should be considered. As codeine is relatively ineffective, research about new antitussive agents should be encouraged.