CFTR heterozygosity in severe asthma with recurrent airway infections: a retrospective review

Rationale Patients with asthma who have neutrophilic bronchitis may have an underlying cause leading to increased susceptibility to airway infections. Methods Retrospective review of patients with asthma who had a previous history of recurrent exacerbations that had been associated with airway or sinus infections referred to a tertiary asthma center between 2005 and 2020. Demographics, clinical features, and airway inflammation type determined by sputum cytometry were compared between CFTR carriers and non-carriers. Multiple linear regression was used to identify clinical predictors of CFTR carrier status. Response to nebulized hypertonic saline was assessed by comparing the number of infective exacerbations before and after its initiation. Results 75 patients underwent CFTR mutation testing. Of these, 13 (17