Use of antibiotics in the treatment of Crohn’s disease

Many data coming from animal models and clinical observations support an involvement of intestinal microbiota in the pathogenesis of Crohn's disease(CD). It is hypothesized in fact,that the development of chronic intestinal inflammation is caused by an abnormal immune response to normal flora in genetically susceptible hosts.The involvement of bacteria in CD inflammation has provided the rationale for including antibiotics in the therapeutic armamentarium.However, randomized controlled trials have failed to demonstrate an efficacy of these drugs in patients with active uncomplicated CD,even if a subgroup of patients with colonic location seems to get benefit from antibiotics. Nitroimidazole compounds have been shown to be efficacious in decreasing CD recurrence rates in operated patients,and the use of metronidazole and ciprofloxacin is recommended in perianal disease.However,the appearance of systemic side effects limits antibiotic long-term employment necessary for treating a chronic relapsing disease.Rifaximin,characterized by an excellent safety profile,has provided promising results in inducing remission of CD.

Vedolizumab for inflammatory bowel disease:from randomized controlled trials to real-life evidence

The biologic antitumor necrosis factor alpha(anti-TNFα) agents have revolutionised the treatment of inflammatorybowel disease(IBD). However,some patients experience primary nonresponse,loss of response,or intolerance. Therefore,introducing a newer class of therapy with a mechanism of action that acts on different inflammatory pathways involved in IBD pathogenesis is appealing. Vedolizumab is a fully humanised monoclonal antibody that selectively targets α4β7 integrin. Based on the results of the pivotal clinical GEMINI trials,vedolizumab was approved for the treatment of adult patients with moderately to severely active ulcerative colitis(UC) and Crohn's disease(CD) refractory or intolerant to either conventional therapy or TNFα inhibitors. This review describes the efficacy,safety,and tolerability of vedolizumab reported in both randomized,controlled,clinical trials and from real-world experience in patients with UC and CD in order to identify its place in treatment algorithms for IBD.

Rifaximin and Crohn's disease

In a recent article,Longman and Swaminath analyzed our paper on the use of rifaximin in patients with moderately active Crohn’s disease(CD).Here we report some considerations concerning their article.The exploratory post-hoc subgroup analysis showed that early-stage disease and,differently from that written by Longman and Swaminath,also colonic involvement seemed to be associated with a significant higher efficacy of rifaximin-EIR 800 mg twice daily.Early-stage disease is generally considered as the more easily treatable phase of CD,and the better response to rifaximin in Crohn’s colitis is in accordance with the high concentration of bacteria in the colon.In addition,patients with C reactive protein level>5 mg/L achieved remission more significantly than patients with normal values,thus suggesting that the symptoms were probably caused by inflammation instead of by non-inflammatory causes.We also analyze the role of rifaximin against gut bacteria and the clinical situations that could obtain the best results from antibiotics.