Introduction Microscopic colitis (MC) encompasses lymphocytic (LC) and collagenous colitis (CC) and typically presents with chronic watery diarrhoea. This retrospective review of biopsy proven cases from 5 DGH reports the clinical characteristics, possible drug precipitants, treatment and outcome in 49 cases.

Methods Retrospective review of patients with histopathological confirmation of MC over a 6-month period between July 2009 and December 2009 across two FTs (5 DGHs). Demographics, clinical presentation including suspected precipitant drugs, investigations, treatment, evolution, and screening for AI diseases were collected. For patients discharged from hospital follow-up, their GPs were contacted to evaluate ongoing symptoms.

Results 49 patients (38 females and 11 males) fulfilled the diagnostic criteria for MC (15 LC and 34 CC). Mean age 66 years (34–90). Mean symptom duration prior to diagnosis was 4.6 months (1–24 months). Main symptoms at the time of diagnosis; diarrhoea (100%), abdominal pain (24.4 %), weight lost (6.1%) and faecal incontinence (8.1%). Diagnosis made by flexible sigmoidoscopy (38.7%) or colonoscopy (61.3%). All patients offered clinic FU (4 DNA). Endoscopic findings reported as grossly normal in all cases. 41 patients were discharged back to GP care and 8 were under active FU in clinic. Of the 41 discharged patients, 10 had at least 1 further flare up of symptoms within 1 year of being discharged. 16 patients were treated pharmacologically: 3 with 5-ASA and 13 with oral Budesonide; 13 had an initial remission and in 6 remained symptomatic at the time of this review. 31 patients (63.26%) did not receive therapy and eight of those reported recurrent flare ups. 36 patients (73.46%) had received drugs reported to be associated with LC at some point and in 22 (61.11%) these had not been discontinued; of these, 7 (22.58%) reported at least one flare up. By registering all medications at diagnosis we found 22 patients were on PPIs, 12 patients on NSAIDs and 8 patients on SSRIs. Coeliac serology was checked in 27 patients and was positive in one patient. 12 patients (24.48%) gave a history of AI diseases.

Conclusion In the absence of specific guidelines, management of MC was highly variable. Only 55.1% of cases were screened for coeliac disease and possible drug precipitants were not routinely detected and in 61.11% of cases these drugs were not discontinued. Gross endoscopic appearances were normal in all cases, reinforcing the need to take colonic biopsies in all cases of unexplained diarrhoea. While the majority of patients were discharged from follow-up, a significant number had re-attended in primary care with recurrent symptoms suggesting the disease burden may be underestimated. Specific national guidelines for the investigation, treatment and follow-up of MC would be valuable.

Competing interests None declared.