Probiotics for the Treatment of Symptomatic Uncomplicated Diverticular Disease: Rationale and Current Evidence

Changes in the colonic microbiota are critical to the pathogenesis of diverticular complications such as diverticulitis and peridiverticular abscesses. However, more subtle changes in microbiota composition may well be important to the more chronic manifestations of diverticulosis. Some studies have shown the presence of bacterial overgrowth in subgroups of patients with diverticular disease and recent studies, using molecular biology techniques, found an increase of proteobacteria and actinobacteria in patients with symptomatic uncomplicated diverticular disease (SUDD), compared with healthy controls. The use of probiotics to modulate intestinal microecology in SUDD appears therefore rational. Although several investigations evaluating the clinical efficacy of probiotics have been performed, no definitive results have yet been achieved, mainly due to the heterogeneity of the available studies. Most of the studies used probiotics in combination with poorly absorbed antimicrobials or anti-inflammatory drugs. In only 4 studies, there was a harm using probiotics alone, but only 1 was a placebo-controlled, double-blind trial. The analysis of the available evidence reveals a poor quality of the published studies, whose design was heterogeneous, with only 2 out of 11 trials being double-blind and randomized. Therefore, available data can only suggest a benefit of probiotics in SUDD, but do not allow any evidence-based definite conclusion. As a consequence, current guidelines state that there is insufficient evidence to recommend probiotics for symptom relief in patients with diverticular disease.