Corticosteroid insensitivity in severe asthma: significance, mechanisms and aetiology.

Chronic severe asthma remains a challenging clinical problem despite the availability of modern treatments. Relative corticosteroid insensitivity is present in severe asthma and may contribute to continuing disease severity. Advances in the understanding of molecular mechanisms underlying corticosteroid insensitivity may yield new therapeutic targets. Furthermore, aetiological factors for corticosteroid insensitivity have been identified and these may be amenable to modification.