Background:Microscopic colitis (MC) encompasses collagenous and lymphocytic
colitis and is diagnosed by histopathological changes of random biopsies which tacken
from each segment of normal macroscopically colonic mucosae from patients who have
ch
ronic watery diarrhea of unknown etiology.
Aims:Prevalence of microscopic colitis in patients with chronic watery diarrhea and
have endoscopically normal colon .
Materials and Methods:We prospectively enrolled 84 patients reviewed in
ALASSAD and TISHREEN HOSPITALS between March 2015 until June 2016 .These
patients were having watery diarrhea more than 3 times a day for more 4 weeks. Atotal 84
patients were enrolled for a total colonoscopy until terminal ileum . Two biopsies were
obtained from all colonic segments and terminal ileum for diagnosed of microscopic
colitis. On histopathologic examination, criteria for lymphocytic colitis (intraepithelial
lymphocyte ≥ 20 per 100 surface epithelial cells, change in surface epithelium,
mononuclear infiltration of the lamina propria) and collagenous colitis (subepithelial
collagen band thickness ≥ 10 μm) were explored.
Results:Microscopic colitis was diagnosed in 33 (39%)patients {22lymphocytic
colitis,11collagenous colitis} . Female/Male: 15/18, mean age at diagnosis of microscopic
colitis : 37 year, range: 20-69, the median duration of diarrhea: 9.5 monthes , the median
number of bowel movements per day:5 times .And the common symptoms are:
abdominal pain and flatulence.
Conclusion :Biopsy of Syrian patients with the diagnosis of chronic watery diarrhea
of unknown etiology and normal colonoscopic findings will reveal microscopic colitis in
approximately 39% of the patients. Lymphocytic colitis is two times more frequent than
collagenous colitis in these patients.
