Objectives: This paper examines the role of antibiotics in treatment of Crohn’s Disease by investigating clinical trials done on the matter. We found antibiotic therapy to be effective in inducing remission or favorable clinical response in adults with active disease. The aim of the study is to perform a meta-analysis on the ability of antibiotics to induce remission or a favorable clinical response in Crohn’s Disease (CD) patients.

Materials and Methods: A meta-analysis of randomized, double-blind, placebo-controlled trials of antibiotics for treatment of CD in adults was conducted. Odds ratio and probability difference were performed to estimate risk difference. The Number Needed to Treat (NNT) was also calculated for each antibiotic reviewed (rifaximin, metronidazole, clarithromycin, and ciprofloxacin).

Results: Thirty-six clinical trial studies were identified, including 3346 patients. Twelve studies reported remission (defined as a CDAI < 150, or authors’ definition) while 24 reported solely a clinical response (defined as a decrease in CDAI or authors’ definition) upon completing an antibiotic regimen. Antibiotics greatly improved patients’ Crohn’s disease activity, with a total response (defined as clinical response plus remission) odds ratio of 1.85 (95% CI: 1.41-2.43), a clinical response odds ratio of 1.87 (95% CI: 1.48-2.37), and a remission odds ratio of 1.90 (95% CI: 1.40-2.57). The Number Needed to Treat for each of the antibiotics used in the clinical trials were 4.17 (Ciprofloxacin), 7.14 (Clarithromycin), 7.14 (Metronidazole), and 9.09 (Rifaximin).

Conclusions: The odds of a Crohn’s Disease patient getting better is higher among those who take antibiotics most notably used in treating Inflammatory Bowel Disease than in placebo. This is an important outcome because it not only opens up a new treatment option for those suffering from Crohn’s Disease, but it also leads credibility to the theory that Crohn’s is caused, at least in part, by bacteria, such as Mycobacterium avium subspecies paratuberculosis (MAP) and adherent-invasive Escherichia coli (AIEC).