Systematic Review of Probiotics for Cystic Fibrosis Patients: Moving Forward

Cystic fibrosis (CF) is associated with chronic respiratory disease and pancreatic insufficiency and results in the malabsorption of nutrients and intestinal inflammation. There is evidence that probiotic supplementation may impact the gastrointestinal and respiratory microbiota. This study aimed to categorize current evidence regarding the effects of supplementing with probiotics in CF patients on gastrointestinal and respiratory outcomes according to the type of intervention.

The initial database search included all identified studies according to the recommendations of the Cochrane Collaboration, regardless of language, publication date or design. Studies were categorized by probiotic strain (Lactobacillus reuteri; Lactobacillus rhamnosus GG or a mix of strains); dosage (low dosage if <10 CFU [colony forming units] or high dosage if >10 CFU); and duration of intervention (1, 3, 6, or 12 months). Assessment of quality was performed based on the Cochrane risk of bias criteria and the Downs & Black checklist.

A total of 205 studies were identified; however, only 9 met the criteria for inclusion. The studies were considered to have a high risk of bias, hampering the possibility of performing a meta-analysis. Eighty percent of the studies (4 of 5) reported a positive result for intestinal inflammation, and another 4 studies (4 of 5) reported a positive result for pulmonary exacerbation frequency, regardless of the treatment approach.

The present data indicate a promising future for probiotic use in cystic fibrosis, which has an impact on exacerbations and intestinal inflammation; however, further studies of standardized therapeutic interventions are required.