Dysbiosis of bifidobacteria and Clostridium cluster XIVa in the cystic fibrosis fecal microbiota

BackgroundRecurrent antimicrobial interventions and disease-related intestinal dysfunction are suspected to contribute to the dysbiosis of the gastrointestinal microbial ecosystem in patients with cystic fibrosis (CF). The present study set out to detect and identify microbial discriminants in the gut microbiota composition that are associated with CF-related intestinal dysbiosis.MethodsAn in-depth description of CF-associated gut dysbiosis was obtained by screening denaturing gradient gel electrophoresis (DGGE) fingerprints for potentially discriminating bacterial species, and quantification by means of real-time PCR analyses using group-specific primers.ResultsA total of 8 DGGE band-classes assigned to the genus Bifidobacterium (n = 3), and members of Clostridium clusters XIVa (n = 3) and IV (n = 2), were significantly (p < 0.05) underrepresented in samples of patients with CF. Real-time PCR analyses confirmed a significantly lower abundance and temporal stability of bifidobacteria and Clostridium cluster XIVa in the fecal microbiota of patients with CF.ConclusionThis study is the first to report specific microbial determinants of dysbiosis in patients with CF.