Does the tissue transglutaminase iga level need to be above or below 0 - 10 to signify celiac disease?

Confusing post: If the level is above 10, it is considered positive for CD, but additional studies, often an intestinal biopsy are required for conclusive labeling. If a person does not make IgA normally, the test could be falsely negative, a TTG-IgG would be needed for the screening test on such a person. In either case, some consumption of gluten for 3 weeks prior to testing is required to assure accuracy.