All children cough, but most children are normal. In a child with isolated cough, a detailed history and examination, followed in a small number of cases by targeted investigations, should allow the child to be placed in one of five diagnostic categories. These are normal child; the child with a serious illness such as cystic fibrosis, tuberculosis etc. the child with non-serious, but treatable causes of cough and wheeze, for example gastro-oesophageal reflux or postnasal drip; the child with an asthma syndrome and an overestimation of symptoms for psychological or other reasons by either or both of child or family. Treatment is of the underlying condition if appropriate. Non-specific treatment with cough syrups are not useful. Attention to environmental factors such as active and passive smoking, and exposure to dust and pets is important. The diagnosis of cough variant asthma should only be made in older children after variable airflow obstruction and response to bronchodilator has been demonstrated physiologically. In younger children, rational diagnostic criteria are an abnormally increased cough, with no evidence of any non-asthma diagnosis, a clear-cut response to a therapeutic trial of asthma medication, usually moderate dose inhaled corticosteroids, and relapse on stopping medications with second response to recommencing them. Some such children go on to develop more typical asthma, with wheeze and bronchial hyper-reactivity. It is important however, not to over-diagnose asthma in children who in fact have a chronic non-specific cough. Such children require no treatment, get better with time, and have normal long-term lung function.
Copyright 2002 Elsevier Science Ltd.