[Chronic cough in childhood].

INTRODUCTION

Although less frequent than viral induced recurrent cough; chronic cough remains a sometimes difficult to resolve diagnostic tool.

STATE OF THE ART

Most authors estimate that a cough can by considered as chronic after three weeks of duration. Few papers have been published concerning etiologic diagnosis of chronic cough in childhood but these indicate the same main causes as in adults: cough variant asthma, postnasal drip syndrome, gastro-esophageal reflux. Nevertheless, each age bracket presents specific diagnosis: malformations between zero and one year, psychogenic cough in adolescents.

PERSPECTIVES

New techniques as induced sputum studies helps to refine chronic cough diagnosis in childhood (after 7 years). Eosinophilic bronchitis, associated or not to bronchial hyperresponsiveness has important therapeutic consequences because associated with a favourable response to corticosteroids. Other techniques will be developed in the future (exhaled NO for example).

CONCLUSIONS

Chronic cough in childhood must be investigated from an anatomic point of view and on frequency arguments. Control and removal of the cough will only be obtained if a precise diagnosis and a suitable treatment are reached.