The airway microbiome in cystic fibrosis: challenges for therapy

Microbiota: A Missing Link in The Pathogenesis of Chronic Lung Inflammatory Diseases

Chronic respiratory diseases account for high morbidity and mortality, with asthma, chronic obstructive pulmonary disease (COPD), and cystic fibrosis (CF) being the most prevalent globally. Even though the diseases increase in prevalence, the exact underlying mechanisms have still not been fully understood. Despite their differences in nature, pathophysiologies, and clinical phenotypes, a growing body of evidence indicates that the presence of lung microbiota can shape the pathogenic processes underlying chronic inflammation, typically observed in the course of the diseases. Therefore, the characterization of the lung microbiota may shed new light on the pathogenesis of these diseases. Specifically, in chronic respiratory tract diseases, the human microbiota may contribute to the disease’s development and severity. The present review explores the role of the microbiota in the area of chronic pulmonary diseases, especially COPD, asthma, and CF.

Does probiotic supplementation affect pulmonary exacerbation and intestinal inflammation in cystic fibrosis: a systematic review of randomized clinical trials

BACKGROUND

Patients with cystic fibrosis (CF) usually have abnormal intestinal microbiota due to massive exposure to antibiotics. Probiotics could modify the gut microbiota and hence may affect CF management. So the aim of present systematic review was evaluation of the efficacy and safety of probiotic supplementation for the management of cystic fibrosis.

DATA SOURCES

We searched PubMed, Science Direct, Google Scholar, Springer Cochrane Library Databases until January 2016 for randomized controlled trials (RCTs) performed in pediatric or adult populations related to the study aim. Key words were selected based on Mesh terms. Based on the Critical Appraisal Skills Programme checklist, eligibility of included articles was evaluated.

RESULTS

Five studies included in this review represent 188 participants with a follow up period ranging from 1 month to 6 months. The results of the included studies supporting the use of probiotics in management of pulmonary exacerbation and intestinal calprotectin in patients with cystic fibrosis. However the level of evidence was limited.

CONCLUSIONS

The lack of high quality RCTs makes it impossible to support a general recommendation about the use of probiotics in the treatment of CF pulmonary exacerbation and intestinal inflammation.

The clinical significance of the gut microbiota in cystic fibrosis and the potential for dietary therapies

Cystic fibrosis (CF) is characterised by many comorbidities related to aberrant mucosa and chronic inflammation in the respiratory and digestive systems. The intestinal mucosa serves as the primary interface between the gut microbiota and endocrine, neural and immune systems. There is emerging evidence that aberrant intestinal mucosa in CF may associate with an altered gut microbiota. Compared to healthy subjects, the overall bacterial abundance and species richness seems to be reduced in CF, accompanied by a trend in suppression of Firmicutes and Bacteroidetes spp. and an augmentation of potentially pathogenic species. There is also some concordance of gut and respiratory microbiotas in CF infants over time. The clinical significance of these observations awaits investigation. The gut microbiota have some potential in CF management by affecting inflammatory and immune responses, and influencing aberrant mucosa. As an important modifiable factor, diet therapies such as probiotics and prebiotics have shown initial promise in improving CF related conditions associated with chronic inflammation. More studies are needed to confirm this, as well as the efficacy of other dietary strategies such as modulating dietary fat and indigestible carbohydrate. Similarly, dietary modification of gut microbiota to optimise nutritional status in CF may be feasible, although more CF-specific studies are warranted.