A Difficult and Rare Diagnosis of Autoimmune Enteropathy in a Patient Affected by Down Syndrome.

Patients with Down syndrome are more susceptible to autoimmune pathologies, in particular endocrine or digestive diseases such as celiac disease. Autoimmune enteropathy is another form of digestive autoimmune disease, non-gluten-dependant, more often diagnosed in male neonates with immunodysregulation and polyendocrinopathy such as the Immunodysregulation, Polyendocrinopathy, Enteropathy, X-linked syndrome. It also exists in the adult, but this pathology is less known and therefore frequently under-diagnosed. Clinical manifestations are similar to celiac disease, but not improved after a gluten-free diet. Autoimmune enteropathy is frequently associated with other autoimmune diseases, such as thyroiditis, myasthenia gravis, lupus or immune deficiencies, as Common Variable Immunodeficiency. Pathological analysis of intestinal biopsies can frequently distinguish autoimmune enteropathy and celiac disease. Autoimmune enteropathy usually has an important lymphoplasmacytic infiltration of the mucosa and a lack of intraepithelial lymphocytes in the gastrointestinal mucosal surface, while celiac disease usually has a polymorph infiltration of the mucosa and an important intraepithelial lymphocytes infiltration. Nevertheless, the two pathological patterns may overlap. Here we report the first case of a patient with Down syndrome associated to autoimmune enteropathy (initially diagnosed as celiac disease), chronic pancreatitis and cutaneous lupus erythematosus. Even if autoimmune pathologies are much more common in patients with Down syndrome, we would like to report on this rare and original association found in our patient.