Duodenal Eosinophil Counts Decrease in Patients with Celiac Disease After Starting a Gluten Free Diet

Eosinophilia has been reported in the intestinal mucosa of patients with celiac disease (CD). The number of eosinophils in the lamina propria (LP) of the duodenum has been correlated with histologic architectural distortion. It is unknown whether instituting the gluten-free diet (GFD) affects eosinophil counts in the mucosal lesion of CD. We identified 25 adults with CD who had initial and follow-up duodenal biopsies. A gastrointestinal pathologist examined each biopsy separately and recorded the following variables: Marsh score, intraepithelial (IE) lymphocytosis (> 30 per 100 epithelial cells), LP granulocytic inflammation (increased eosinophils compared to normal mucosa or any extravascular neutrophils), and maximum eosinophil count per high-powered field (HPF). The initial diagnostic biopsies had significantly increased rates of IE lymphocytosis (88% vs 20%, p=0.0003) and LP eosinophilia (72% vs 20%, p=0.0003) as compared to the follow-up biopsies, while rates of extravascular neutrophils were not significantly different between diagnostic and follow-up biopsies. The mean maximum eosinophil count in a single HPF was increased in the diagnostic biopsy as compared to the follow-up biopsy (45.5 vs 18.7, p<0.0001). At follow-up biopsy, the mean maximum eosinophil count per HPF was increased in biopsies with persistent villous atrophy as compared to those without (27.8 vs 15.8, p=0.015). In patients with CD, LP duodenal eosinophils are higher at diagnosis than on follow-up biopsies; this decrease over time may be related to the GFD. The implications for risk of allergic disease development in this population warrant further investigation.