Congenital Tufting Enteropathy

Congenital Tufting Enteropathy is a rare congenital enteropathy presenting with early-onset severe and intractable diarrhea that leads to irreversible intestinal failure.

Epidemiology

No epidemiological data is available, however, the prevalence can be estimated at around 1/200,000 births in Europe. The prevalence is higher in areas with high degrees of consanguinity, but cases have been reported worldwide.

Clinical description

Most affected patients develop digestive intolerance with vomiting and watery diarrhea within the first few months of life. Diarrhea is severe, chronic and persistent despite bowel rest, resulting in electrolyte imbalance and dehydration. Moreover, an intestinal insufficiency leads to malabsorption, malnutrition, and growth impairment. Although most children present with isolated diarrhea, a small number of congenital tufting enteropathy (CTE) patients present with a syndromic form where diarrhea is associated with non-specific punctuated keratitis, and various malformations such as choanal atresia, esophageal atresia, imperforate anus, dysmorphic features, skeletal dysplasia, and (in one case) Dubowitz syndrome.

Etiology

CTE is related to abnormal enterocyte development and differentiation. Mutations in the EPCAM gene (2p21) are seen in 73% of CTE patients and are associated with the isolated intestinal disease. Mutations in the SPINT2 gene (19q13.2) are seen in 21% of CTE cases which are clinically characterized by the syndromic form of the disease. Rarely, CTE patients may present with isolated diarrhea but have no mutations in either EPCAM or SPINT2.

Diagnostic methods

Diagnosis is based on the combination of clinical and histological criteria. A congenital chronic diarrhea in the absence of an infectious or an inflammatory process, in association with various degrees of small and large bowel villous atrophy and specific histological abnormalities involving the focal crowding of surface enterocytes resembling ''tufts'', and branching crypts, allow for the diagnosis of CTE. When not all criteria are obvious one can be helped by the association of the non-syndromic form of the disease with negative EpCAM immunostaining on patient's duodenal biopsies; or conversely in case of the syndromic form of the disease with a normal EpCAM immunostaining. To date, SPINT2 immunostaining on duodenal biopsies seems useless for the diagnosis. Molecular genetic testing, identifying a mutation in the EPCAM gene or SPINT2 can confirm diagnosis, however, some CTE patients do not have any identified genetic mutations.

Differential diagnosis

The differential diagnosis primarily includes other protracted congenital diarrhea disorders such as microvillus inclusion disease, congenital chloride diarrhea, congenital sodium diarrhea, and syndromic diarrhea, as well as glucose-galactose malabsorption.

Antenatal diagnosis

Prenatal diagnosis is available but can only be offered to families where a first case has already been described. The rarity of CTE and the absence of prenatal signs do not make it an appropriate candidate for either antenatal or postnatal mass screening.

Genetic counseling

CTE is transmitted in an autosomal recessive manner with high prevalence of consanguinity and affected siblings in families.

Management and treatment

To date there is no known curative treatment for CTE. Oral or enteral feedings worsen the diarrhea, however they should be maintained at the minimum tolerated level. CTE patients require daily, long-term parenteral support in order to maintain an adequate nutritional status. Life threatening complications related to intestinal failure and long-term parenteral nutrition may become an indication for intestinal transplantation, thus timing of referral to an expert center is crucial before the onset of severe complications.

Prognosis

Currently, children with CTE reach adulthood if long-term parenteral nutrition is conducted appropriately in an experienced center, otherwise the long-term prognosis may be reserved due to the complications of this delicate palliative treatment.