The trachea with an air-fluid level: a rare and bizarre radiological sign.

We report three children with an unusual radiological sign: "trachea with an air fluid level." We suggest this is related to paucity of cough leading to recurrent chest infections. Voluntary cough suppression as a cause of chronic lower respiratory tract infection is recorded in adults (The Lady Windermere Syndrome) but has not previously been reported in children. We propose that in these children impaired airway mucus clearance may be also be caused by voluntary cough suppression. However, the complex physiology of coughing means it is difficult to distinguish between true voluntary cough suppression and paucity of cough due to a subtle neurological deficit. In two patients, the cycle has led to permanent lung damage with bronchiectasis and reduced lung function. In the third, early diagnosis and multidisciplinary intervention has so far delayed progression to bronchiectasis. With greater awareness of this phenomenon in children, there is potential for effective early intervention with medical, physical, and psychological therapies.