Chronic cough is typically defined as a cough lasting more than four weeks. This is because most acute respiratory infections in children resolve within this interval. Other schemes define chronic cough as one that last more than eight weeks but also recognize that a relentlessly progressive cough often warrants evaluation prior to eight weeks.
The evaluation of a child with chronic cough should include a detailed history, physical examination, chest radiograph, and spirometry (if the child is able). If the initial evaluation provides clues suggesting a specific cause of cough (ie, caused by an underlying disease), further evaluation is focused on that diagnostic possibility (algorithm 1). The steps are detailed in a separate topic review. (See "Approach to chronic cough in children".)
The causes of chronic cough in children are quite different from that of adults, so evaluation and management of children should not be based on adult protocols. The most clinically important causes of cough in children and the initial steps in management are reviewed here. Adolescents 15 years and older may be evaluated using guidelines for adults . (See "Evaluation of subacute and chronic cough in adults".)
A cough that is caused by an underlying abnormality or disease is termed a specific cough. The causes of specific chronic cough fall into the following general categories (table 1):