Recent advances in cystic fibrosis

The prevalence of nasal polyps in adults with cystic fibrosis

The endoscopic intranasal appearance of 211 adult patients with cystic fibrosis was studied. The prevalence of nasal polyps in this study was 37%. The commonest nasal symptoms were discharge, headache and obstruction. Intranasal endoscopy usually demonstrated mucosal oedema and thin, clear discharge. The prevalence of allergy, as diagnosed by skin prick testing, was almost twice that of the general population. Tympanometry showed that middle ear effusion was uncommon in these patients.

Impaired stimulus-evoked mucus secretion in cystic fibrosis bronchi

Baseline and agonist-stimulated secretion of fucose, hexose, and protein (markers of mucus secretion) was investigated in vitro in 45 bronchial segments from 14 patients with cystic fibrosis (CF) (three after heart-lung transplant, the remainder < 4.5 h after autopsy), in 51 segments from 26 patients with carcinoma (24 resection, 2 after autopsy), and in 4 segments from 3 patients with bronchiectasis (resection). Basal rates of secretion of each mucus marker by CF bronchi were not significantly different from those by carcinoma bronchi bronchiectatic bronchi. However, rates of secretion of each marker in response to the cholinomimetic methacholine (10 microM; n = 11-18, depending on marker) and the beta 2-adrenoceptor agonist terbutaline (10 microM; n = 9-11) were significantly (p < .05) increased in carcinoma bronchi (by 50-117% above basal), but not in CF airways (n = 11-14). The secretory response to the sensory neuropeptide substance P (1 nM to 10 microM; n = 5-7) was also reduced in CF compared with carcinoma bronchi. Physiological and morphological data indicated that the reduced response by CF tissue could not be accounted for by inclusion of autopsy tissue in the study. These data suggest a defect in autonomic control of bronchial secretion in CF, not in the basal rate of secretion, but in its response to receptor stimulation.