Antibiotics should be used as first-line therapy for Crohn's disease.

The etiology of Crohn's disease remains uncertain, and to date no therapy is curative. Recent experimental evidence suggests that an altered immune response to commensal enteric flora in a genetically susceptible host plays a key role in both the development and perpetuation of the intestinal inflammation of Crohn's disease. Thus, incorporation of antibiotics into the therapeutic armamentarium for Crohn's disease, either as first-line therapy or combined with immunomodulatory drugs, would seem to be a rational strategy. Indeed, most IBD clinicians would attest to the marked benefit of antibiotic therapy in individual patients. Skepticism surrounding this approach arises because evidenced-based analyses' show that the few clinical trials evaluating the efficacy of antibiotics for Crohn's disease have produced equivocal or negative results or have methodological deficiencies, including small number of patients and absence of a placebo group. However, by undertaking an analysis that integrates information from both basic and clinical spheres of study, the dichotomy between experimental and clinical observations tends to merge. This approach underscores certain key factors that determine an optimal response to antibiotics, emphasizes the requirement for assessment in well-defined subsets of patients, and leads to the conclusion that antibiotics do provide benefit for Crohn's disease.