A Bush

Abstract

Most children with asthma respond to low doses of inhaled corticosteroids, but a few remain symptomatic despite being prescribed the routine usual asthma medications. The first steps are to ensure the diagnosis is correct, and that the inhaled medications are being given with an appropriate device. If the child continues to be symptomatic, with any or all of chronic symptoms, acute exacerbations, the need for regular oral corticosteroids, or persistent airflow limitation, then they are considered to have problematic, severe asthma. The next step is to perform a detailed evaluation, including a nurse-lead home visit, to determine if the child has difficult to treat asthma, which improves if the basics are got right, or severe, therapy resistant asthma, which latter group would be candidates for cytokine specific therapies. If severe, therapy resistant asthma is the likely issue, then detailed invasive investigation is performed, including a bronchoscopy, bronchoalveolar lavage and endobronchial biopsy, and trial of adherence with a single intramuscular injection of depot triamcinolone. After detailed phenotyping, an individualised treatment plan is determined. Future work will determine the roles of proximal and distal inflammation, as well as the relative importance of intramural (mucosal) and intraluminal infection. The stability of paediatric asthma phenotypes over time is more variable than those of adults, and the implications of a change of phenotype are yet to be determined.