Microscopic colitis in children.

backgroundMicroscopic colitis typically presents with chronic watery nonbloody diarrhea with normal endoscopy findings but abnormal inflammatory histopathological findings. As it is mainly a condition of the elderly, pediatric data is scarce.

aimsTo describe and characterize children with microscopic colitis.

methodsThe pathology database at the University of Alberta Hospital together with the pediatric inflammatory bowel disease database at the Stollery Children's Hospital were both searched from September 1996 to May 2008. Charts of all children under the age of 17 years who fulfilled the diagnostic criteria of microscopic colitis were examined.

resultsEleven children (four girls, mean age at diagnosis 11.2 years, +/- 4.4 years) fulfilled the inclusion criteria. The patients were followed up for a mean of 24.8 months (standard deviation, SD 15.2 months). Two patients were on proton pump inhibitors, two had stool organisms, and two had immunodeficiency. All patients had normal endoscopy and colonoscopy on visualization. Five patients were diagnosed with lymphocytic colitis and the rest had nonspecific/eosinophilic microscopic colitis. The majority of children responded to mesalazine. One patient with immunodeficiency was difficult to manage.

conclusionsMicroscopic colitis is rare in children. Microscopic eosinophilic colitis is an underdescribed variant of microscopic colitis. The majority of children with microscopic colitis respond well to aminosalicylic acid (5-ASA) medications. Microscopic colitis associated with immunodeficiency can be very challenging to manage. Large multicenter pediatric trials with long-term follow-up are needed to allow investigators to have a better understanding of this rare condition in children.