The corticosteroid budesonide is the most effective treatment for patients with microscopic colitis (MC), according to a meta-analysis in the October issue of Clinical Gastroenterology and Hepatology. However, once patients stop taking this drug, the rate of symptom relapse is high.
MC is an inflammatory disorder of the colon that causes watery, non-bloody diarrhea, especially among older women. Its incidence has increased in recent years, approaching that of ulcerative colitis and Crohn’s disease.
Budesonide is a potent corticosteroid that is frequently used to treat MC, because it has less systemic absorption and fewer adverse effects than other steroids. However, budesonide is less efficacious than conventional steroids in the treatment of ulcerative colitis and Crohn’s disease. Michael J. Stewart and colleagues performed a meta-analysis of 8 clinical trials (236 patients) to evaluate the effects of corticosteroids for short- and long-term treatment of MC.
They found that budesonide was well-tolerated and effective for short- and long-term treatment of each subtype of MC (collagenous colitis and lymphocytic colitis). Patients were 3 times more likely to have a clinical response to a 6- to 8-week course of budesonide than to placebo, with no increase in risk for adverse events. The patients that received budesonide also had a much higher rate of histologic response (based on biopsy analysis). Another steroid, prednisolone, was not effective as a short-term therapy.
Although budesonide produced an impressive clinical response, 46%–80% of patients had symptom relapse within 6 months of discontinuing the drug. Stewart et al. state that further studies are required to determine how to achieve the maximal sustained effects of budesonide and how to withdraw or reduce the dosage, to minimize symptom relapse. They would also like to determine whether alternating courses of budesonide might better control symptoms and whether the addition of other therapies improves its effects.
The best strategy for patients with microscopic colitis is not clear—management has focused on treating associated conditions, such as celiac disease, avoiding certain dietary factors and medications, and treating the diarrhea symptoms. A number of pharmacologic and alternate therapies (including probiotics) have been used with varying degrees of success, but few randomized controlled trials have been performed. According to Stewart et al., there have been no controlled trials of commonly used immunosuppressive medications such as azathioprine or methotrexate as maintenance therapy for patients with unremitting disease.
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Stewart MJ, Seow CH, Storr MA. Prednisolone and budesonide for short- and long-term treatment of microscopic colitis: systematic review and meta-analysis. Clin Gastroenterol and Hepatol 2011; 9:881–890.