Cystic fibrosis is a rare genetic disease that is characterized by serious respiratory and digestive disorders. The intestinal microbiota may be involved in the pathophysiology and progression of this disease.
Cystic fibrosis is a lethal recessive genetic disease, caused by mutations in the CFTR* gene. These mutations generate a deficiency or absence of functional CFTR proteins in the apical membrane of epithelial cells, leading to an increase in mucus viscosity and its accumulation in the respiratory and digestive tracts. In the digestive tract, the disease causes pancreatic insufficiency that affects digestion and nutrient absorption. In the lungs, it promotes infections by opportunistic bacteria (Staphylococcus aureus, Pseudomonas aeruginosa and Hemophilus influenzae), leading to the progressive loss of pulmonary function until the patient’s death.
Cystic fibrosis occurs in 1 in 2500 births in Europe and North America, while its prevalence is low in Africa and Asia1.
Dysbiosis and cystic fibrosis
The exacerbation of secretions also modifies the environment of the intestinal microbiota, and as such, its composition. A decline in microbiota diversity (changes in Firmicutes, Bacteroidetes, and Actinobacteria) has been observed in patients with cystic fibrosis compared to healthy volunteers. Multiple factors are at the root of this dysbiosis: the pathophysiology of the disease, the type of CFTR mutation, exposure to antibiotics, etc2,3. This dysbiosis, which occurs very early in the individual’s life, contributes significantly to undernutrition, failure to thrive, and long-term morbidity4.
Potential use of probiotics
Standard treatment targets airway clearance and digestive disorders: chest physiotherapy associated with bronchial decongestants, bronchodilators, and a hypercaloric diet including pancreatic extracts and vitamins.
In patients with cystic fibrosis, probiotics have been shown to reduce pulmonary exacerbation, intestinal inflammation, and the length of hospital stays5-8. Other studies, with larger cohorts and longer durations, are necessary to confirm the advantages of probiotics5‑8.
* Cystic Fibrosis Transmembrane conductance Regulator
2- Schippa S et al. Cystic fibrosis transmembrane conductance regulator (CFTR) allelic variants relate to shifts in fecal microbiota of cystic fibrosis patients. PLoS One. 2013;8:e61176.
3- Burke et al. 2017 The altered gut microbiota in adults with cystic fibrosis Burke et al. BMC Microbiology (2017) 17:58
4- Juliette C Madan. Neonatal gastrointestinal and respiratory microbiome in cystic fibrosis : potential interactions and implications for systemic health. Clin ther 2016 ; 38 : 740-46. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5206974/
5- Bruzzese E et al. Intestinal inflammation is a frequent feature of cystic fibrosis and is reduced by probiotic administration. Aliment Pharmacol Ther. 2004;20:813–9.
6- Bruzzese E et al.. Effect of Lactobacillus GG supplementation on pulmonary exacerbations in patients with cystic fibrosis: a pilot study. Clin Nutr. 2007;26:322–8
7- Weiss B et al. Probiotic supplementation affects pulmonary exacerbations in patients with cystic fibrosis: a pilot study. Pediatr Pulmonol. 2010;45:536–40.
8- del Campo R et al. Improvement of digestive health and reduction in proteobacterial populations in the gut microbiota of cystic fibrosis patients using a Lactobacillus reuteri probiotic preparation: a double blind prospective study. J Cyst Fibros. 2014;13:716–22.