Biography
Biography: Mario Guslandi
Abstract
Background: Diverticular disease of the colon is a common condition, the prevalence of which increases with age. In most subjects diverticula remain asymptomatic, whereas in about 20% of cases patients develop symptoms such as recurrent abdominal pain, changing in bowel habits and bloating, which are very similar to the clinical presentation of irritable bowel syndrome. On the other hand diverticulosis may lead to acute inflammation (diverticulitis) with pain exacerbation, sometimes fever and the risk of further complications such as abscess formation, bleeding and perforation. The main cause of diverticular inflammation is thought to be local bacterial overgrowth, promoted by slow colonic transit (constipation) and fecal stasis in the diverticula. HIgh-fiber diet, courses of mesalazine and especially cyclic administration of poorly absorbed antibiotics such as rifaximin, are commonly employed to prevent development of inflammation in the diverticula. Broad spectrum antibiotics either by oral or intravenous route are employed to treat episodes of acute diverticulitis.
Rationale: Manipulation of the gut microbiota may provide a safer and more attractive alternative to the use of antibiotics to prevent diverticulitis. The mechanisms of action of probiotics include inhibition of enteric pathogens, competition with pro-inflammatory microbes, stimulation of local immunological defenses, and down-regulation of inflammatory cytokines such as TNF alfa.
Results: Uncontrolled studies with non-pathogen Escherichia coli Nissle 1917, with Lactobacillus paracasei, a lactobacilli bifidobacteria mixture, and the probiotic cocktail VSL#3 have provided promising results in controlling symptoms and maintaining remission. Other studies have compared probiotics with either mesalazine or a combination of both, the latter appearing more effective in maintaining long-term remission. On the other hand, only two randomized, placebo-controlled double blind trials are available at the present time, one suggesting that Lactobacillus casei plus mesalazine may be more effective than either agent alone and the other one failing to demonstrate a significantly superior efficacy of either Bifidobacterium infantis or mesalazine or a combination of both.
Conclusions: Overall, the quality of the available studies on the use of probiotics is poor, due to the shortage of double-blind controlled studies, limited observational periods in most cases, small samples of included subjects and variable protocols, which make it impossible also to perform a meta-analysis. In view of the sound rationale and the promising, although still inconclusive results, further studies are warranted to better define the role of probiotics in this disorder.