Résumé
Chronic cough is defined as a cough that lasts for more than three weeks. In most patients, chronic cough is caused by four conditions: postnasal drip, asthma, chronic bronchitis, gastroesophageal reflux. Psychogenic chronic cough is not a frequent disorder. Furthermore, chronic vocal tic disorder is a very rare cause of chronic dry cough. A 22- year-old male suffered from chronic dry cough for last two years. His character showed obsessive- compulsive disorder. He has been shrugging both shoulders inadvertently since his childhood. Consequently, he was diagnosed as having chronic motor tic disorder. But after contracting respiratory tract infection, his motor tic disappeared and chronic dry cough was developed concomitantly. He had no history of smoking, chronic rhinitis, sinusitis, asthma, and gastroesophageal reflux. Physical examinations were normal. Chest X-ray, paranasal sinus view, metacholine bronchial provocation test, and esophago-gastroscopy were normal. Chronic cough was never relieved despite empirical treatment. Psychiatric consultation suggested chronic vocal tic disorder. The frequency of cough was diminished two days after administeration of valium and haloperidol and thereafter his complaint disappeared in one month. Here we report a very rare case of chronic motor tic disorder which was transformed into chronic vocal tic disorder presenting as a chronic cough. As far as we know, this is the first case of its kind in Korea.