Regional mucociliary clearance in patients with cystic fibrosis

This paper reports on a large retrospective analysis of mucociliary clearan ce (MCC) studies in a group of 59 patients with cystic fibrosis (CF) and 17 age-matched healthy subjects. As many of the CF patients were studied on m ultiple occasions, a total of 184 patient studies are presented. MCC was me asured using a radioaerosol and gamma camera technique. In addition to whol e lung clearance, MCC was measured from the central, intermediate, peripher al, basal, mid and apical regions of the lung. MCC was markedly decreased i n the CF patient group. Not only was whole lung clearance (14.2 +/- 1.4% vs . 28.0 +/- 3.7%) impaired, but also clearance from the central (19.1 +/- 1. 9% vs. 35.6 +/- 4.3%), intermediate (10.7 +/-1.6% vs. 25.5 +/- 3.7%), apica l (12.4 +/- 2.6% vs. 31.6 +/- 4.6%) and mid (14.0 +/- 1.9% vs. 30.4 +/- 4.0 %) regions. Attempts were made to identify factors that may have influenced MCC in both the normal subjects and CF patients. Age, gender, body mass in dex, patient genotype, penetration index, spontaneous cough, and various lu ng function parameters were entered into a stepwise multiple regression mod el, but none of the factors proved to be statistically important in determi ning MCC. Both intrasubject repeatability and intersubject variability esti mates are presented for the patients and normal subjects that had multiple studies. The values were found to be remarkably similar for both CF patient s and normal subjects and for both intra- and intersubject repeatability. W ith marked deviation from normal ranges and good repeatability, the measure ment of MCC in CF patients would seem to be a valuable outcome measure for clinical trials involving new pharmaceuticals and physical therapy designed to improve removal of secretions from the airways.