Background

Recombinant human deoxyribonuclease I (rhDNase) cleaves DNA in mucus, allowing for increased mucociliary clearance of purulent sputum. RhDNase in cystic fibrosis (CF) patients improves pulmonary function and decreases exacerbations. Conversely, rhDNAse use in non-CF bronchiectasis patients has not yielded similarly effective results.  We explored the effectiveness of rhDNAse in patients with bronchiectasis due to primary ciliary dyskinesia (PCD).

Methods

We provided rhDNase to PCD patients suffering from viscous mucus and moderate to severe bronchiectasis.  Patients were instructed to use the medication up to once daily, primarily when their sputum became viscous.  We monitored the patients over six months of usage, tracking pulmonary function tests, pulmonary exacerbations and quality of life.

Results

We tracked ten PCD patients with moderate-severe bronchiectasis, with an average forced expiratory volume in the first second (FEV1) of 49%.  Average use of rhDNase was three times weekly.  As compared to prior to rhDNase, patients reported increased overall quality of life, based on the Bronchiectasis Health Questionnaire. Average number of pulmonary exacerbations were reduced from 4 to 3 in the comparable periods. Pulmonary function tests, as measured by forced vital capacity and FEV1, remained stable or mildly improved compared to six months prior to rhDNase.  

Conclusion

Use of rhDNase in PCD patients lead to improved quality of life and decreased exacerbations, without impacting lung function, in contrast to trial results in non-CF bronchiectasis with heterogeneous etiologies.  Further clinical data is required to identify the population of PCD patients who can benefit from rhDNase.