There are currently no guidelines for screening everyone with autoimmune thyroid disease for celiac disease, or screening those with celiac disease for thyroid disease. Recent research has suggested there may be an opportunity to catch those folks that may still be undiagnosed with celiac disease. A 2012 study found mal-absorption of the medication used to treat hypothyroidism was common in patient with untreated or undiagnosed celiac disease. This mal-absorption leads to higher doses than normal being needed to control the thyroid disease. As more and more doctors (and patients) become aware of this link the door will be opened to more quickly screen for celiac disease and possibly detect celiac disease in a population that was previously overlooked.
Collins D, Wilcox R, Nathan M, Zubarik R. Celiac disease and hypothyroidism. Am J Med. 2012 Mar; 125(3): 278-282.
Virilli C, et al. Atypical Celiac Disease as Cause of Increased Need for Thyroxine: A Systematic Study. J Clin Endocrinol Metab. 2012 Jan 11.