Hello, I'm Dr. Dan Neumann for About.com here to help you navigate the clinical testing for celiac disease. Celiac is a disease in which the toxic effects of gluten cause damage to the finger-like projections along the surface of the small intestine. It is this blunting of the body’s normal absorptive mechanism that leads to the clinical, serologic and histologic manifestations of celiac disease. Let’s first talk about the basic non-invasive studies available to test for celiac disease. When patients present with symptoms suggestive of possible malabsorption, a thorough review of their dietary and family history is a great place to start. There is a strong genetic component with celiac disease and patterns of celiac symptoms among first degree relatives can often heighten suspicion for this condition. Anyone who has a first degree relative diagnosed with celiac should be tested, regardless of symptoms. Beyond the history, simple blood tests are often the next step. These blood samples can determine the level of antibodies that become elevated in people with celiac disease. Over 90 percent of people with untreated celiac disease will have elevated antibody levels, while these levels are rarely elevated in those patients without celiac disease. Before having these tests however, it is important to continue eating a normal diet, including foods that contain gluten. Avoiding or eliminating gluten can cause antibody levels to be normal, thus further delaying or missing the diagnosis celiac disease. Next, let’s discuss what to do if this testing demonstrates elevated levels of antibodies in the blood. To confirm the suspected diagnosis of celiac disease, your doctor may refer you to a gastroenterologist to undergo endoscopy and a small bowel biopsy. This painless test allows for a sample of tissue to be obtained from your small intestine. To get this sample, a flexible, fiber-optic camera can be passed through the mouth and advanced into the small intestine, all while the patient is comfortable under moderate sedation. A pathologist will then view the specimen under the microscope and measure the height of the intestinal villi. It is these villi which are damaged by gluten which results in a diminished capacity to absorb nutrients. Although biopsy is the gold-standard for diagnosing celiac disease, this testing is invasive and is usually reserved for those patients for whom there is a high suspicion for disease. I hope this has provided you with a better understanding of how we test for celiac disease. Once again, I’m Dr. Dan Neumann and for more information on this topic and others, visit us on the web at health.about.com.