Chronic cough in children: when to investigate?

Only in some particular cases chronic cough requires special investigations . Respiratory diseases linked to environment are frequent in children. Coug h is the most common symptom in child asthma and usually occurs during slee p or exercise. Environmental tobacco smoke exposure may concern up to 30% o f families. Questioning should systematically check for parental smoking in children with chronic cough since avoidance is the only effective treatmen t. The incidence of whooping cough appears to be increasing and the diagnos is may be difficult among already immunized children in whom symptoms are o ften nonspecific. Nowadays Bordetella pertussis can easily be detected on n asal smears (ELISA, PCR, cultures). Swallowing dysfunction may cause produc tive cough in toddlers, most often related to functional dyspraxia, yet pos sibly due to aerodigestive tract malformation. Unrecognized bronchial forei gn body is a well-known pitfall particularly between 9 and 36 months of age . Bronchiectasis and cystic fibrosis are responsible for chronic productive cough in toddlers and older children. In teenagers, psychogenic coughing i s difficult to manage and usually requires psycho- and speech therapy. (C) 2001 Editions scientifiques et medicales Elsevier SAS.