By Van Waffle
Summary: Australian researchers in collaboration with Boston biotech company ImmusanT used new criteria to determine the prevalence of celiac disease. From a random population, it found more than 1 percent were affected. This is higher than most previous studies anywhere in the world. The researchers recommend that screening for the disease should shift to include genetic testing along with the usual serology blood test.
Conventional screening looks for immunoglobin A and anti-transglutaminase antibodies in the blood. In addition, recent research has identified celiac gene markers. A blood test or cheek swab can detect a person’s genetic predisposition to developing the disease. The new study combined antibody and genetic tests to see whether this could provide more effective screening. Positive screening must be followed by a biopsy, a tissue sample from the bowel to look for flattened villi for a conclusive diagnosis.
The researchers analyzed serology from 356 celiac disease patients and a random sample of 2,500 Australians. Whenever possible, they followed positive screening with a bowel biopsy. They found that at least one in five people who tested positive for antibodies did not possess the genes for celiac disease. These turned out to be false positives. Subsequent biopsies and diagnoses indicated that at least 1.3 percent of women and 1.2 percent of men in the general population were affected by celiac disease.
Conclusion: Combining genetic screening with blood tests for antibodies uncovers a higher incidence of celiac disease than previously thought. Although the study occurred in Australia, the population there is considered similar to North America and Europe, so this calls for re-evaluation. Genetic testing can also reduce the number of false positives, and cut down the risk and medical cost of biopsies. Also, since many patients balk at undertaking the invasive procedure, it may reduce the number of people unnecessarily adopting a restrictive diet without diagnosis.
 “A novel serogenetic approach determines the community prevalence of celiac disease and informs improved diagnostic pathways”, Anderson RP, Henry MJ, Taylor R, Duncan EL, Danoy P, Costa MJ, Addison K, Tye-Din JA, Kotowicz MA, Knight RE, Pollock W, Nicholson GC, Toh B, Brown MA, Pasco JA, BMC Medicine 2013 Aug 28; 11:188.