Effect of Rifaximin on Intestinal Bacterial Overgrowth in Crohn's Disease as Assessed by the H2-Glucose Breath Test

SummaryThe occurrence of intestinal bacterial overgrowth in patients with Crohn's Disease (CD) has been described and antimicrobial treatment has been shown to be effective in reversing this condition. However, the mechanisms underlying the efficacy of antimicrobial therapy are still only partially known.The aim of the present study was to evaluate the effect of a non-absorbable antibiotic (rifaximin) in comparison to placebo on bacterial overgrowth in patients with CD.Methods Fourteen patients with inactive CD of the ileum and bacterial overgrowth, as assessed by the hydrogen breath test, were blindly allocated to receive rifaximin (1200 mg/day) or placebo t.i.d. for one week. A hydrogen breath test, and clinical and biochemical parameters were further performed 14 days and 30 days after starting treatment.Results After 14 days, the hydrogen breath test proved to be negative in seven out of seven patients treated with rifaximin (p < 0.05), and in two out of seven in the placebo group (p = ns). After 30 d...