TERMINAL ILEAL MUCOSAL MAST-CELLS IN IRRITABLE-BOWEL-SYNDROME

Terminal ileal biopsies were prospectively obtained and stained specif ically for mast cells in 20 patients with irritable bowel syndrome (IB S) and 15 controls. The number of terminal ileal mast cells per high p owered field (MC/HPF) (mean +/- SEM) was 23.3 +/- 3.1 for IBS and 6.8 +/- 1.1 for controls (P = 0.0001). The diarrhea IBS subgroup had the g reatest number of MC/HPF. No correlation was found between terminal il eal mucosal mast cell counts (MMCC) and the number of Manning criteria present or the functional bowel disease score (r = 0.06 and r = -0.31 , respectively). We conclude that terminal ileal MMCC are significantl y elevated in a majority of patients with IBS. The mast cell may be re sponsible for the altered visceral perception found in the gastrointes tinal tract in patients with IBS. The poor correlation of the MMCC to the clinical features of IBS may be the result of the dynamic state of the mast cell.