Long-term treatment with mesalazine and rifaximin versus rifaximin alone for patients with recurrent attacks of acute diverticulitis of colon

BACKGROUND/AIMS: To compare efficacy of combined therapy with rifaximin and mesalazine versus rifaximin alone in treatment of patients with recurrent diverticulitis in order to evaluate: 1) rapidity in improvement of symptoms, 2) regulation of bowel attacks, 3) prevention of recurrence of diverticulitis. METHODS: A total of 218 consecutive eligible patients (131 males, 87 females age 64.3 years, range 51-79), affected by diverticulitis were monitored. Of these, 109 patients were treated with rifaximin 400 mg bid plus mesalazine 800 mg tid for 7 days, followed by rifaximin 400 mg bid plus mesalazine 800 mg bid for 7 days/month (group A); 109 patients were treated with rifaximin 400 mg bid for 7 days, followed by rifaximin 400 mg bid for 7 days/month (group B). Colonoscopy was performed after 3, 6 and 12 months of therapy. RESULTS: At end of follow-up, 193 patients were fully compliant to therapy Two patients died during study (1 in group A, 1 in group B), while four patients were lost to follow-up 1 in group A (0.91%) and 3 in group B (2.75%)]. The only side-effects recorded were transient urticaria (1 in group B, 0.91%) and epigastric pain (9 in group A, 8.25%). Severity of symptoms improved significantly in group A vs group B within 3 months (p < 0.005, p < 0.001 and p < 0.0001 and p < 0.0005 at 3, 6, 9 and 12 months, respectively). Bowel habits inproved significantly in group A vs group B within 3 months (p < 0.005, p < 0.0005, p < 0.001 and p < 0.0001 at 3,6,9 and 12 months respectively). Symptomatic recurrence of diverticulitis occurred in 3 patients in group A, while 13 patients showed recurrence of diverticulitis in group B (p < 0.005) during follow-up. CONCLUSIONS: This study clearly shows that rifaximin plus mesalazine are more effective than rifaximin alone in resolution of symptoms and prevention of recurrence of diverticulitis.