Celiac disease, also known as gluten-sensitive enteropathy (as well as two older and less preferred terms, nontropical sprue and celiac sprue) is a multisystem disorder estimated to affect approximately 1% of Americans (1). It results from an inappropriate T-cell–mediated immune response to ingested gluten that causes inflammatory injury to the small intestine in genetically predisposed persons. Damage to the proximal small intestinal mucosa results in the malabsorption of nutrients. The average age of diagnosis is in the fifth decade of life but only an estimated 10% to 15% of persons with celiac disease in the United States have been diagnosed (2). The prevalence of celiac disease in the United States seems to have increased 4- to 5-fold over the past 3 to 4 decades (3). Disease manifestations are protean, and gastrointestinal symptoms are not always present. Virtually every body system can be affected, with dermatologic, hematologic, neurologic, musculoskeletal, endocrine, reproductive, and digestive systems most commonly involved. Moreover, celiac disease is associated with a variety of autoimmune conditions whose clinical course may be affected by the diagnosis and treatment of celiac disease. Although patients respond well to treatment with a gluten-free diet, unrecognized or untreated celiac disease is associated with both increased mortality (3, 4) and risk for intestinal lymphoma (5).