Letters to The Editor
To the Editor: Lemale et al (1) published a comprehensive review on the histology and associated clinical outcomes of 7 patients with clinical congenital tufting enteropathy (CTE), concluding that histological features cannot predict outcomes and that new biomarkers would be helpful. This latter conclusion is perplexing because, as cited by the authors, mutations in the epithelial cell adhesion molecule (EpCAM) have been linked to CTE in 2008 (2). Furthermore, the sequencing of this gene can provide a genetic diagnosis. It would have been invaluable to have included EpCAM sequencing in their cohort. Phenotypic overlaps with other forms of congenital diarrheas (eg, syndromic congenital sodium diarrhea) can complicate the clinical diagnosis of CTE (3). Therefore, molecular testing could have aided the genetic confirmation of CTE and the potential delineation of novel genotype–phenotype correlations. In fact, homozygous single base pair mutations (c.498insC) in EpCAM have already been associated with a milder, total parenteral nutrition–free course of CTE in 1 patient (4). This latter patient developed chronic arthropathy around 4 years of age, whereas a nearby heterozygous splice-site mutation (c.491 + 1G > A) was detected in a child with CTE who developed juvenile rheumatoid arthritis at 5 years (5). Chronic arthropathy and mild dysmorphic features are the only extraintestinal manifestations that have been associated with EpCAM-linked CTE. Similar genotype–phenotype correlations could have been drawn from the study of Lemale et al, and would have been useful for the prognostics of future patients and the unraveling of CTE pathogenesis. It is hoped that this group will report these test results in the near future.
1. Lemale J, Coulomb A, Dubern B, et al. Intractable diarrhea with tufting enteropathy: a favorable outcome is possible. J Pediatr Gastroenterol Nutr
2. Sivagnanam M, Mueller JL, Lee H, et al. Identification of EpCAM as the gene for congenital tufting enteropathy. Gastroenterology
3. Sivagnanam M, Schaible T, Szigeti R, et al. Further evidence for EpCAM as the gene for congenital tufting enteropathy. Am J Med Genet A
4. Al-Mayouf SM, Alswaied N, Alkuraya FS, et al. Tufting enteropathy and chronic arthritis: a newly recognized association with a novel EpCAM gene mutation. J Pediatr Gastroenterol Nutr
5. Ko JS, Seo JK, Shim JO, et al. Tufting enteropathy with EpCAM mutations in two siblings. Gut Liver