Relationship between cough, cough receptor sensitivity and asthma in children

In childhood asthma, cough is a major symptom in some but not in others. There is only limited data on the frequency, severity and prevalence of cough in children with classical asthma. Studies have largely shown no relationship between cough frequency and cough receptor sensitivity with various asthma severity indices. However relating cough severity with asthma severity is limited by various methodological and sensitivity issues, and these are presented in this paper. Mild asthma exacerbations in a group of children with cough as a dominant symptom were characterised by an increase in cough severity (daytime cough scores) and eosinophilic inflammation but not neutrophilic inflammation. However neither cough receptor sensitivity or cough scores related to airway IL-8, eosinophil cationic protein, myeloperoxidase or serum eosinophil cationic protein, and, asthma scores consistently related to cough score only early in the asthma exacerbation phase.