Microscopic colitis: clinical characteristics, treatment and outcomes in an Irish population

Many aspects of microscopic colitis remain poorly understood. Our aim was to report a single centre experience with this condition.

Two hundred and twenty-two patients (52 male, 170 female; median age 64 years; range 32-90) diagnosed between 1993 and 2010 were studied. Medical notes were reviewed, and data on age, gender, clinical features, history of autoimmune diseases, medication use, cigarette smoking, histology and outcome were collected.

There were 99 cases of lymphocytic and 123 of collagenous colitis. Diarrhoea was almost invariably present (98 %) while abdominal pain (24 %), weight loss (10 %), faecal incontinence (8 %) and blood PR (5 %) were also described. Twenty-eight percent had concomitant autoimmune diseases, most commonly coeliac disease. Patients were taking a variety of medications at diagnosis thought to be associated with microscopic colitis including NSAIDs (22 %), aspirin (19 %), statins (15 %), proton pump inhibitors (19 %) and SSRIs (10 %) at diagnosis. Prior to the widespread use of budesonide in our institution, 33 % of patients required two or more medications during therapy compared to 15 % following the introduction of budesonide (p = 0.001). Thirty-eight percent of patients achieved spontaneous remission with either no treatment or simple anti-diarrhoeals. Using a multivariate model, the only factor associated with spontaneous remission was male gender (RR 1.9; 95 % CI 1.0-3.6; p = 0.04). Two patients had refractory microscopic colitis; one required a colectomy while a more recent case has responded to anti-TNFα therapy.

Microscopic colitis is predominantly a benign and self-limiting disorder. The introduction of budesonide has revolutionised treatment of this lesser studied inflammatory bowel disease.