Mast cells (MCs) have been thought to affect how irritable bowel syndrome (IBS) works. Still, it is not clear how many MCs are in the gastrointestinal tract of children with IBS or where they are located. The goal of this study was to compare the number of MCs in children with and without IBS and to set pediatric reference values for histopathology. Prospectively, 49 people with IBS were signed up and put into 2 groups: IBS with atopy (n=29) and IBS without atopy (n=20). Researchers chose 42 people with a history of polyposis syndrome or gastroesophageal reflux disease who had normal histopathology to be our control group.

The control group was chosen in a way that was similar to adult and child studies that had already been published. Immunohistochemical staining was done on the stomach, duodenum, terminal ileum, and descending colon of both groups to look for MCs. No matter if they were allergic or not, the IBS group hacells per high-power field (MCs/HPF) in the stomach, duodenum, terminal ileum, and descending colon (P<0.001).

Optimal MC cutoff values for IBS are more than equal to 20.5 MCs/HPF in the stomach (area under the curve [AUC]=0.84); greater than equal to 23.0 MCs/HPF in the duodenum (AUC=0.79); greater than equal to 33.5 MCs/HPF in the terminal ileum (AUC=0.82); and greater than equal to 22.5 MCs/HPF in the descending colon (AUC=0.86). Compared to controls, kids with IBS had more MCs in their stomach, duodenum, terminal ileum, and descending colon than kids who didn’t have IBS. More tests are needed to figure out what role MCs play in IBS in children, which could help with the development of targeted treatments.