PubMed · 5900736
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
J P Light. 1966. Chronic bronchitis.. https://pubmed.ncbi.nlm.nih.gov/5900736/
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Risk factors for severe wheezing bronchitis were studied in children aged 4 months to 4 years in need of hospitalization. The children included in the study consisted of all cases generated from a geographically defined population, the catchment area of St Göran's hospital in Stockholm. The incidence was 3/1000 children and year, during the two years of observation, with the highest rate in boys under the age of 18 months (4.7/1000). Symptoms of a preceding upper respiratory tract infection were reported in 90% of the cases, but a viral etiology could only be demonstrated with virus isolation in 26%. Respiratory syncytial virus was the most common finding in younger children. Rhinovirus was primarily seen in older children with a history of previous wheezing. Regardless of whether the cases had a positive or negative virus isolation they showed the same seasonal distribution. Furthermore, there was no difference in risk factors between children with a positive and negative virus isolation. Children older than 18 months with negative virus isolation had higher IgE levels than those with positive isolation, suggesting that atopy is of greater importance in this group.
At this time, dornase is approved only for the treatment of patients with cystic fibrosis. Based on the results of the trials discussed, dornase appears to be well tolerated by patients with chronic bronchitis. However, the therapeutic benefit of dornase in chronic bronchitis remains unclear. Until further studies are published, dornase cannot be recommended as a routine treatment modality for management of patients with chronic bronchitis.
Recombinant human deoxyribonuclease (rhDNase) has been demonstrated to reduce in vitro the viscosity and to improve the transport capacity of purulent respiratory mucus in cystic fibrosis. During episodes of exacerbation of chronic bronchitis, the patients generally expectorate purulent mucus. Purulence of mucus is associated with an increased deoxyriboneucleic acid (DNA) concentration. We analyzed in vitro the potential effect of rhDNase on chronic bronchitis mucus transport by the ciliary activity (frog palate model) and by simulated cough (cough machine model), as well as the effect on mucus viscosity (controlled stress rheometer) and surface properties (contact angle). Purulent sputa collected from patients with chronic bronchitis (n = 15) during an episode of exacerbation were incubated for 30 min at 37 degrees C with either rhDNase at two different concentrations (final concentration 2 or 4 micrograms.mL-1) or placebo. The median mucociliary transport rate was significantly improved by rhDNase from 0.68 with placebo to 0.79 and 0.83 with 2 and 4 micrograms.mL-1 of rhDNase, respectively. A significant improvement in mucus cough transport was also induced by rhDNase from 25.5 mm with placebo to 27.0 mm with either 2 or 4 micrograms.mL-1 rhDNase. These improvements in mucus transport capacity were associated with alterations in the physical properties of the mucus. The mucus median control viscosity (511.4 Pa.s) and median contact angle (0.85 rd) significantly decreased to 112.5 Pa.s and 0.74 rd, respectively, in the presence of 4 micrograms.mL-1 of rhDNase. These findings demonstrate that recombinant deoxyribonuclease may exert a beneficial effect on mucus clearance in vitro by altering the viscosity and surface properties of the purulent chronic bronchitic sputum samples.