Currently, the gold standard for diagnosing celiac disease is to biopsy a tiny portion of the small intestine to look for specific signs of intestinal damage. These tests are costly and invasive, and since the prevalence of celiac is greater than 1% of the Canadian population, there is an increasing demand for better diagnostic methods. The steps toward confirming a celiac disease diagnosis include the physician requesting a blood test that screens for certain antibodies associated with celiac disease, typically followed by a biopsy to confirm a diagnosis. However, as the blood tests become more precise, they could be edging out the biopsy as the gold standard in some cases.
A recent retrospective study published in the Journal of Pediatric Gastroenterology, Hepatology, and Nutrition1 analyzed patients younger than 18 years of age whose symptoms suggested a potential celiac disease diagnosis. Researchers compared the subjects’ blood test results, small intestine biopsy findings, and the effectiveness of a gluten-free diet on reducing symptoms. The researchers found that in the 114 children who had a level of ≥100 U/mL of certain antibodies (anti-transglutaminase antibodies, or tTGA) and whose symptoms improved upon starting a gluten-free diet, a small intestine biopsy might not have been necessary to confirm diagnosis. However, the blood testing was not as reliable for the children who had lower levels of tTGA (<100 U/mL).
The researchers note that no current blood test is 100% accurate for identifying celiac disease, and they recommend that physicians continue to perform biopsies in most cases. However, the researchers are confident that a specific group of symptomatic individuals – those whose blood tests reveal sufficiently high levels of certain antibodies and who also experience remission of symptoms after starting a gluten-free diet – do not require a biopsy to confirm a celiac disease diagnosis, cutting down some of the need for costly, invasive biopsies.