A Novel Nonsense Mutation in the EpCAM Gene in a Patient With Congenital Tufting Enteropathy

OBJECTIVES: Tufting enteropathy (TE) is a classical congenital disorder of the intestinal mucosa causing protracted diarrhea in infancy as a result of a dysfunctional epithelial cell barrier, which is mainly caused by mutations in the EpCAM gene and expression of a nonfunctional epithelial cell adhesion molecule in the intestine. We report here a novel nonsense mutation in a patient suspected of having TE, resulting in a complete absence of EpCAM in duodenal enterocytes. METHODS: A patient presenting with congenital diarrhea and suspected of having TE was screened for EpCAM mutations, and duodenal biopsies were stained for EpCAM using immunohistochemistry analysis. RESULTS: We identified a novel homozygous nonsense mutation in the EpCAM gene in a patient suspected of having TE, causing a complete loss of EpCAM expression in duodenal enterocytes. CONCLUSIONS: With screening analysis for EpCAM mutations and immunohistochemistry for EpCAM expression in duodenal enterocytes, we found a novel homozygous mutation in a patient with classical protracted diarrhea in infancy finally diagnosed as TE, which results in a complete absence of EpCAM and in dysfunctional barrier formation in duodenal enterocytes.