Blood tests as good as genetic typing for celiac detection

Experts say biopsy remains the gold standard for diagnosis, and gene testing still has a role.

By Victoria Stagg Elliott, AMNews staff. Sept. 24, 2007.

Combining serologic with genetic testing is not a better strategy for diagnosing celiac disease than either test alone, and intestinal biopsy remains the definitive procedure, according to a study in the Sept. 4 Annals of Internal Medicine.

Combining the use of newer genetic tests with more well-established screening for celiac-related antibodies in the blood has long been discussed as a possibility to improve diagnostic accuracy and reduce the number of people undergoing biopsies. To help settle this debate, researchers at the VU University Medical Center in Amsterdam, the Netherlands, used both modalities on 463 patients referred for biopsy. Sixteen were determined actually to have this condition, but both tests had nearly equal specificity. Using them together was not more accurate.

"If you add genetics to the serology, does it improve the sensitivity? The answer is no. Adding this will not increase the level of confidence in making the diagnosis," said Dr. Alessio Fasano, director of the University of Maryland Center for Celiac Research in Baltimore. He was not affiliated with this study.

Experts complimented the study's elegant design but said it highlighted the challenge of detecting celiac disease, which can have very nonspecific symptoms that mimic many other conditions. It also lacks a conclusive, noninvasive test to diagnose it. Most hold the blood testing in high regard, but it still can miss some patients who go on to have a positive biopsy.