Large Granular Lymphocytic Leukemia: A Treatable Form of Refractory Celiac Disease

Large granular lymphocyte leukemia (LGL) is characterized by clonal expansion of CD3+ T cells or CD3− natural killer cells and frequently is associated with autoimmune diseases. We describe 2 patients with celiac disease who no longer responded to gluten-free diets after they developed T-cell LGL, with intestinal localization of malignant lymphocytes. Flow cytometry phenotyping of isolated intestinal intraepithelial and lamina propria cells eliminated type II refractory celiac disease, identifying large-sized CD8+CD57+ T cells. Treatment with a combination of cyclosporine and methotrexate restored the patients' sensitivity to gluten-free diets. LGL therefore might be a cause of refractory celiac disease that is sensitive to immunosuppressive therapy.