Diagnosis of pediatric inflammatory bowel diseases (IBD) remains challenging. We aimed at the value of immunohistochemical assessment of CD30+ lymphocytes in the intestinal mucosa in differential diagnosis between pediatric Crohn's disease (CD) and ulcerative colitis (UC) and its utility as a predictor of future differentiation in patients with IBD unclassified (IBDU).
Seventy-four treatment naive pediatric patients with IBD (33 CD, 30 UC and 11 IBDU) were enrolled into the study. Biopsy samples from six different regions (terminal ileum, cecum, ascending colon, transverse colon, descending colon and rectum) were immunohistochemically stained with anti-CD30 antibody, and the number of positive cells per one high power field was quantified.
Significant differences between CD and UC were found when compared total counts of CD30+ cells in median numbers, mean values and maximal numbers and also for separate counts in terminal ileum, transverse colon, descending colon and rectum. The most profound difference between CD and UC was shown for total median values of CD30+ cells and for the values in rectal localization.
The difference was independent on the intensity of inflammation. A cutoff value of 2.5 CD30+ cells with sensitivity 83% and specificity 90% was found for the rectum.
There was no difference between patients with CD and IBDU, but a marked difference between UC and IBDU patients was revealed. Histopathological assessment of biopsy with rectal CD30+ count is reliable and simple method that could help in differential diagnosis among IBD subtypes in children with IBD.