Villous Atrophy
IPEX syndrome - Patients develop intractable chronic diarrhea secondary to autoimmune small bowel inflammation (the colon can also be affected). The diarrhea may be watery, bloody or mucoid. Biopsy of the bowel reveals villous atrophy and lymphocytic infiltrates in the mucosa. The villous atrophy closely resembles the GI tract changes seen in celiac disease. Apoptosis of GI tract epithelial cells resembling gut GVHD can also be seen. Additional features of this disease include atopic dermatitis, endocrinopathies (Type I diabetes and thyroid disease), and autoimmune cytopenias.
CD25 Deficiency - IPEX syndrome-like disease has been described in patients with CD25 deficiency.
STAT1 Gain of Function Mutation
STAT1 (Gain of function mutation) - IPEX syndrome-like disease has been reported in patients with gain of function STAT1 mutations.
CVID - Patients are at risk for developing a number of GI tract pathologies including lymphoid nodular hyperplasia and inflammatory bowel disease. An enteropathy with villous blunting (resembling celiac disease) may be present but does not respond to dietary gluten removal. The risk of developing GI tract malignancies (lymphoma, adenocarcinoma) is increased 50 fold.