Rossella Romagnoli

Probiotics - Role in inflammatory bowel disease

The aetiology of inflammatory bowel disease is still unclean. Whilst a specific pathogen agent associated with these diseases has not been found, the rationale for probiotic therapy in inflammatory bowel disease is based on convincing evidence involving intestinal bacteria in their pathogenesis. Encouraging results have been obtained with probiotic therapy in several animal models of experimental colitis. The administration of highly concentrated probiotic preparations represents a valid approach both for the prevention of pouchitis onset and relapses. The encouraging results obtained in ulcerative colitis and Crohns disease need to be further assessed in large double-blind trials.

Standard Treatment of Ulcerative Colitis

Ulcerative colitis (UC) is an idiopathic, chronic inflammation of the colon which may present with a range of mild to severe symptoms. The disease may be localized to the rectum or can be more extensive and involve the left side of the colon or the whole colon. Treatment in UC is directed towards inducing and maintaining remission of symptoms and mucosal inflammation. The key parameters to be assessed for the most appropriate treatment are the severity and extent of the inflammation. Meta-analyses of published trials have shown that topical treatment with 5-aminosalicylic acid (5-ASA) is the treatment of choice in active distal mild-to-moderate UC. Oral aminosalicylates are effective in both distal and extensive mild-to-moderate disease, but in distal disease, the rates of remission are lower than those obtained with topical 5-ASA. New steroids, such as budesonide and beclomethasone dipropionate (BDP), administered as enemas, constitute an alternative to 5-ASA therapy. In some studies, these have been shown to be as effective as conventional steroids but with significantly lower inhibition of plasma cortisol levels. Patients with unresponsive disease or those with more severe presentation will require oral corticosteroids and sometimes intravenous therapy. Approximately 10% of patients with unresponsive UC have severe attacks requiring hospitalization. Patients with severe disease should be managed jointly by a medical and surgical team, and intensive intravenous treatment should be started with high-dose steroids. Early recognition of failure of therapy will allow the introduction of immunosuppressive therapy with intravenous cyclosporine. Patients who respond are shifted to oral cyclosporine associated with azathioprine/6-mercaptopurine, whereas those who fail will require proctocolectomy. Oral aminosalicylates are the first-line therapy in maintenance of remission. Topical 5-ASA may play a role in distal disease. Patients who are steroid dependent can be started on azathioprine or 6-mercaptopurine although it may take up to 3 months for the treatment to become effective. They may have reversible immediate side effects, such as pancreatitis or bone marrow suppression, which disappear upon discontinuation of therapy. Close monitoring of these hematologic and biochemical parameters will improve safety. The use of biologic therapy with infliximab in more severe disease has not been established.

Monitoring activity in ulcerative colitis

The monitoring of patients with ulcerative colitis is easier than in patients with Crohns disease for several reasons: the severity of symptoms and activity of inflammation tend to run parallel in ulcerative colitis when involvement of the large bowel is more extensive. The easy accessibility of the colonic mucosa by endoscopic and histologic examination provides further information concerning the degree of inflammation. In severe attacks, the patient must be admitted to hospital and monitored carefully. Clinical and laboratory parameters (such as daily stools, CRP, fever, haemoglobin, albumin, etc.) and plain abdominal X‐ray are useful in monitoring the activity of the disease and to predict the outcome. In mild to moderate attacks, endoscopic and histologic evaluation are the best methods for choosing the appropriate treatment and for assessing response.

Management of Inflammatory Bowel Disease: Does Rifaximin Offer Any Promise?

An increasing number of both clinical and laboratory-derived observations support the importance of luminal components in driving the inflammatory response in ulcerative colitis and Crohn’s disease. Although its role is unclear, antibiotic therapy is commonly used in clinical practice for the treatment of moderately to severely active ulcerative colitis. Metronidazole and/or ciprofloxacin are currently employed in active Crohn’s disease, particularly in patients with colonic involvement and with perianal disease. Rifaximin, a rifamycin-derived antibiotic, is characterized by a wide range of antibacterial activity and a very low systemic absorption. Some preliminary data show its efficacy in severe active ulcerative colitis, pouchitis and prevention of postoperative recurrence in Crohn’s disease.