Background: Both, Faecalibacterium prausnitzii (Fpra), and Fpra phylogroups (PGH-I and PHG-II), combined with Escherichia coli (Ecoli), are an accurate biomarker to distinguish healthy (H) from diseased, and also among different clinical manifestations and disease locations (Lόpez-Siles et al, 2016). The purpose of this study was to verify this capability in faecal samples, in order to develop a non-invasive system for diagnostic support.
Methods: A Spanish cohort consisting of 23 IBD (10 CD and 8 UC) and 12 H was enrolled. Sixty seven faecal samples (26 CD, 30 UC and 11 H) fecal samples were obtained during their treatment. Fpra total, PHG-I, PHG-II and Eco abundances were quantified by qPCR.
Results: Fpra and PHG-II were less abundant in IBD patients, compared with healthy subjects (p=0.046 and p=0.009, respectively). In turn, abundance of Ecoli was higher in IBD patients (p=0.007) (with sensitivities and specificities between 60%-85%). As compared to H, CD patients displayed lower abundance of Fpra l, PHG-I and PHG-II (p=0.014, 0.045 and 0.004) and higher of Eco (p=0.001). Finally, PHG-II loads were lower for Fpra and higher for Eco in samples from UC patients (p=0.050 and p=0.047).
Concerning disease localization, significant differences were observed in CD. Fpra and PHG-I abundances were lower in the colon (p=0.046 and p=0.026), whereas PHG-II was significantly higher in the ileum (p=0.032).
UC and CD with colon affectation could also be distinguished; a lower abundance of PHG-I and Eco (p=0.020 and p=0.048) was observed in samples of colon CD, with sensitivities and specificities between 70%-100%.
Conclusions: Fecal loads of total Fpra and related phylogroups correlate with those describe on biopsy samples.
Ecoli and PHG-I seem to be good markers to discriminate between patients with UC and CD with colonic affectation.
 Mireia Lόpez-Siles, (2016), Changes in the Abundance of Faecalibacterium prausnitzii Phylogroups I and II in the Intestinal Mucosa of Inflammatory Bowel Disease and Patients with Colorectal Cancer, Inflammatory Bowel Diseases