Cystic fibrosis, primary ciliary dyskinesia and non-cystic fibrosis bronchiectasis: update 2008-11

Increased intracellular Cl- concentration promotes ongoing inflammation in airway epithelium

Airway epithelial cells harbor the capacity of active Cl^- transepithelial transport and play critical roles in modulating innate immunity. However, whether intracellular Cl^- accumulation contributes to relentless airway inflammation remains largely unclear. This study showed that, in airway epithelial cells, intracellular Cl^- concentration ([Cl^-]_i) was increased after Pseudomonas aeruginosa lipopolysaccharide (LPS) stimulation via nuclear factor-κB (NF-κB)-phosphodiesterase 4D (PDE4D)-cAMP signaling pathways. Clamping [Cl^-]_i at high levels or prolonged treatment with LPS augmented serum- and glucocorticoid-inducible protein kinase 1 (SGK1) phosphorylation and subsequently triggered NF-κB activation in airway epithelial cells, whereas inhibition of SGK1 abrogated airway inflammation in vitro and in vivo. Furthermore, Cl^--SGK1 signaling pathway was pronouncedly activated in patients with bronchiectasis, a chronic airway inflammatory disease. Conversely, hydrogen sulfide (H₂S), a sulfhydryl-containing gasotransmitter, confers anti-inflammatory effects through decreasing [Cl^-]_i via activation of cystic fibrosis transmembrane conductance regulator (CFTR). Our study confirms that intracellular Cl^- is a crucial mediator of sustained airway inflammation. Medications that abrogate excessively increased intracellular Cl^- may offer novel targets for the management of airway inflammatory diseases.

Newborn Cystic Fibrosis Pigs Have a Blunted Early Response to an Inflammatory Stimulus

RATIONALE

Studies suggest that inappropriate responses to proinflammatory stimuli might contribute to inflammation in cystic fibrosis (CF) lungs. However, technical challenges have made it difficult to distinguish whether altered responses in CF airways are an intrinsic defect or a secondary effect of chronic disease in their tissue of origin. The CF pig model provides an opportunity to study the inflammatory responses of CF airways at birth, before the onset of infection and inflammation.

OBJECTIVES

To test the hypothesis that acute inflammatory responses are perturbed in porcine CF airways.

METHODS

We investigated the inflammatory responses of newborn CF and non-CF pig airways following a 4-hour exposure to heat-killed Staphylococcus aureus, in vivo and in vitro.

MEASUREMENTS AND MAIN RESULTS

Following an in vivo S. aureus challenge, markers of inflammation were similar between CF and littermate control animals through evaluation of bronchoalveolar lavage and tissues. However, transcriptome analysis revealed genotype-dependent differences as CF pigs showed a diminished host defense response compared with their non-CF counterparts. Furthermore, CF pig airways exhibited an increase in apoptotic pathways and a suppression of ciliary and flagellar biosynthetic pathways. Similar differences were observed in cultured airway epithelia from CF and non-CF pigs exposed to the stimulus.

CONCLUSIONS

Transcriptome profiling suggests that acute inflammatory responses are dysregulated in the airways of newborn CF pigs.

The Likelihood of Preventing Respiratory Exacerbations in Children and Adolescents with either Chronic Suppurative Lung Disease or Bronchiectasis

Chronic suppurative lung disease (CSLD) and bronchiectasis in children and adolescents are important causes of respiratory morbidity and reduced quality of life (QoL), also leading to subsequent premature death during adulthood. Acute respiratory exacerbations in pediatric CSLD and bronchiectasis are important markers of disease control clinically, given that they impact upon QoL and increase health-care-associated costs and can adversely affect future lung functioning. Preventing exacerbations in this population is, therefore, likely to have significant individual, familial, societal, and health-sector benefits. In this review, we focus on therapeutic interventions, such as drugs (antibiotics, mucolytics, hyperosmolar agents, bronchodilators, corticosteroids, non-steroidal anti-inflammatory agents), vaccines and physiotherapy, and care-planning, such as post-hospitalization management and health promotion strategies, including exercise, diet, and reducing exposure to environmental toxicants. The review identified a conspicuous lack of moderate or high-quality evidence for preventing respiratory exacerbations in children and adolescents with CSLD or bronchiectasis. Given the short- and long-term impact of exacerbations upon individuals, their families, and society as a whole, large studies addressing interventions at the primary and tertiary prevention phases are required. This research must include children and adolescents in both developing and developed countries and address long-term health outcomes.

Chest CT Features of Cystic Fibrosis in Korea: Comparison with Non-Cystic Fibrosis Diseases

OBJECTIVE

Cystic fibrosis (CF) is a rare congenital disease in Korea, and its clinical and imaging findings are unclear. The objective of our study was to describe the clinical and CT features of CF in Korea and compare its features with those of other diseases mimicking CF.

MATERIALS AND METHODS

From November 1994 to December 2014, a presumptive diagnosis of CF was made in 23 patients based on clinical or radiological examination. After the exclusion of 10 patients without diagnostic confirmation, 13 patients were included in the study. A diagnosis of CF was made with the CF gene study. CT findings were evaluated for the presence and distribution of parenchymal abnormalities including bronchiectasis, tree-in-bud (TIB) pattern, mucus plugging, consolidation, and mosaic attenuation.

RESULTS

Of the 13 patients, 7 (median age, 15 years) were confirmed as CF, 4 (median age, 19 years) had primary ciliary dyskinesia, 1 had bronchiectasis of unknown cause, and 1 had chronic asthma. CT of patients with CF showed bilateral bronchiectasis, TIB pattern, mosaic attenuation, and mucus plugging in all patients, with upper lung predominance (57%). In CT of the non-CF patients, bilateral bronchiectasis, TIB pattern, mosaic attenuation, and mucus plugging were also predominant features, with lower lung predominance (50%).

CONCLUSION

Korean patients with CF showed bilateral bronchiectasis, cellular bronchiolitis, mucus plugging, and mosaic attenuation, which overlapped with those of non-CF patients. CF gene study is recommended for the definitive diagnosis of CF in patients with these clinical and imaging features.

Relationship between chronic rhinosinusitis and lower airway diseases: An extensive review

Significant links between allergic rhinitis and asthma have been reported, and the united airway disease hypothesis is supported by numerous findings in epidemiologic, physiologic, pathologic, and immunologic studies. The impact of allergic rhinitis on asthma has been established. On the other hand, the relationship between chronic rhinosinusitis and lung diseases has been under investigation. Chronic rhinosinusitis is a common disease, and the high prevalence of chronic rhinosinusitis in some kinds of lung diseases has been reported. Recent studies suggest that the treatment of chronic rhinosinusitis has beneficial effects in the management of asthma. Here, we present an overview of the current research on the relationship between chronic rhinosinusitis and lower airway diseases including asthma, chronic obstructive pulmonary disease, cystic fibrosis, diffuse panbronchiolitis, primary ciliary dyskinesia, idiopathic bronchiectasis, and allergic bronchopulmonary aspergillosis.

Sinonasal alterations in computed tomography scans in cystic fibrosis: a literature review of observational studies

BACKGROUND

Almost all cystic fibrosis (CF) patients reveal upper airway involvement in computed tomography (CT) scans. Sinonasal pathology has become a challenging issue because there are few studies to guide appropriate management. The objective of this study was to provide information about paranasal sinus CT manifestations in CF patients, mainly in adulthood.

METHODS

We performed a literature review of descriptive studies about CT sinonasal findings in CF patients using the following databases: MEDLINE, EMBASE, Web of Science, LILACS, Scielo, and Cochrane.

RESULTS

Eighteen articles were included in this review. There was a high variability in methodological aspects for most of the studies. The most prevalent findings reported were opacification of sinuses, presence of frontal and sphenoidal aplasia or hypoplasia, underdevelopment of paranasal sinuses, and medial bulging of the lateral nasal wall in CT scans.

CONCLUSION

There are few studies in the CF adult population regarding sinonasal CT alterations. Many studies report specific pathological features in CF upper airways that could help in the diagnosis of doubtful cases.