P720 Anti-TNF-a induction regimen modulates gut microbiota molecular composition while inducing clinical response in Crohn's Disease patients: Toward a personalised medicine
F. Scaldaferri*1, V. Gerardi1, S. Pecere1, V. Petito1, L. Lopetuso1, D. Zambrano1, E. Schiavoni1, D. D'Ambrosio1, A. D'Agostino1, L. Laterza1, F. Paroni Sterbini2, F. Franceschi1, E. Gaetani1, G. Cammarota1, M. Sanguinetti2, L. Masucci2, A. Gasbarrini1
1Catholic University of Sacred Heart, Internal Medicine Department, Gastroenterology division, Rome, Italy, 2Catholic University of Sacred Heart, Microbiology, Rome, Italy
IBD is characterized by an imbalance between immune response and microbiota composition. Anti-TNF-a is one of strongest therapeutically options with high immune modulation potential. No information exists on how and whether anti-TNF-a modulates gut microbiota composition.
Aim of our study was to evaluate gut microbiota composition in Crohn's disease patients before and after 6 weeks of anti-TNF-a therapy (mean age 41, 3 male).
Fecal samples were collected in 6 consecutive CD patients, (3 Infliximab, 3 adalimumab) and stored at -80°C. No antibiotic were admitted 4 weeks before starting anti-TNF-a therapy or during the active treatment. Microbiota composition was assessment by 16S rRNA analysis (Roche 454 GS Junior), following DNA isolation from stool samples. Data obtained were analyzed by suite Qiime.
Clinical response was defined as a decrease of 2 points at Harvey Bradshaw Index (HBI) compared to baseline, while clinical remission was consider for HBI <4.
Bacteria amplicons were detected in all samples. Six weeks after anti-TNF-a therapy, Bacteroidetes decreased in 2 patients (one of the 2 in clinical remission) and remained stable in 4 patients. Roseburia spp increased in one patient (not in clinical remission), Ruminococcus spp decreased in 2 patients (in one not responder to treatment). F. Prausnitzii increased in 3 patients (one in clinical remission). Finally, Enterobacteriaceae increased in 3 patients (one not responder to therapy). Chao index increased in 5 patients of six after 6 week. Patients non-responder to anti-TNF by 12 weeks did not show increase in Bacteroidetes at 6 weeks.
Anti TNF-a treatment is associated to active modulation of intestinal microbiota while inducing clinical response. Reduction of enterobacteriacee and ruminococcus were associated to clinical response to antiTNF-a, together with increase in bacteroidetes and F. Prausnitzii. Further studies are required considering a major number of patients.