American Society for Microbiology, American Society for Clinical Laboratory Science and American Society for Clinical Pathology

View all recommendations from this society

November 7, 2022

Don’t order tissue transglutaminase IgG antibody or Deamidated Gliadin Peptide (DGP) antibodies (IgG or IgA) in the initial screening for Celiac Disease.

Tissue transglutaminase IgA antibody (anti-tTG IgA) is the recommended first-line screening test for celiac disease because it provides the best diagnostic sensitivity and specificity. Serum IgA should also be included to detect IgA deficiency. Tissue transglutaminase IgG antibody (anti-tTG IgG) or deamidated gliadin peptide antibodies (IgG or IgA) could be appropriate as reflex tests in specific situations based on initial findings although they have less specificity than the tissue transglutaminase IgA antibody. In particular, Deamidated Gliadin Peptides result in a higher false positive rate that can lead to further unnecessary testing and/or endoscopy.

These items are provided solely for informational purposes and are not intended as a substitute for consultation with a medical professional. Patients with any specific questions about the items on this list or their individual situation should consult their physician.

How The List Was Created

(1–2) The American Society for Microbiology’s (ASM) list was developed under the leadership of the ASM’s Clinical and Public Health Microbiology Committee. The subject matter experts who identified the list and formulated the recommendations are laboratory directors at academic, commercial and public health laboratories and test utilization experts across the fields of microbiology and laboratory medicine. They worked together to identify a list of diagnostic and management decisions that have resulted in misuse of laboratory studies and resources.

In this submission, two statements were written to address the most common clinical microbiology laboratory test misconceptions. They consist of diagnostic tests or treatments that are commonly ordered, expensive and have no evidence to illustrate its value and in some cases, may be potentially harmful to the patient. The recommendations, if instituted, would result in higher quality care, lower costs, and more effective use of our laboratory resources and personnel. The experts involved in the new 2022 recommendations are James Dunn, Laura Filkins, Omai Garner, Elizabeth Palavecino and Preeti Pancholi.How This List Was Created

(3–4) These ASCLS recommendations were developed under the leadership of ASCLS’s Choosing Wisely Committee and the ASCLS Board of Directors. The Committee examined numerous options based on evidence available. Subject matter experts from the ASCLS Scientific Assemblies reviewed, edited, and recommended approval of these recommendations, which were subsequently reviewed and approved by the ASCLS Board of Directors.How This List Was Created

(5) The American Society for Clinical Pathology (ASCP) recommendation was developed under the leadership of the ASCP Effective Test Utilization Steering Committee. This committee is chaired by an ASCP Past President and is comprised of subject matter and test utilization experts across the fields of pathology and laboratory medicine. The committee considered a list of possible recommendations compiled as the result of a survey administered to Society members serving on ASCP’s many commissions, committees and councils. In addition, an announcement was made to ASCP’s Advisory Board seeking suggestions for possible recommendations to promote member involvement. The laboratory tests targeted in our recommendations were selected because they are tests that are performed frequently; there is evidence that the test either offers no benefit or is harmful; use of the test is costly and it does not provide higher quality care; and eliminating it or changing to another test is within the control of the clinician. Implementation of these recommendations will result in higher quality care, lower costs and a more effective use of our laboratory resources and personnel.


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Husby S, Koletzko S, Korponay-Szabó I, Kurppa K, Mearin ML, Ribes-Koninckx C, Shamir R, Troncone R, Auricchio R, Castillejo G, Christensen R, Dolinsek J, Gillett P, Hróbjartsson A, Koltai T, Maki M, Nielsen SM, Popp A, Størdal K, Werkstetter K, Wessels M. European Society Paediatric Gastroenterology, Hepatology and Nutrition Guidelines for Diagnosing Coeliac Disease 2020. J Pediatr Gastroenterol Nutr. 2020 Jan;70(1):141-156. doi: 10.1097/MPG.0000000000002497. PMID: 31568151.

Husby S, Murray JA, Katzka DA. AGA Clinical Practice Update on Diagnosis and Monitoring of Celiac Disease-Changing Utility of Serology and Histologic Measures: Expert Review. Gastroenterology. 2019 Mar;156(4):885-889. doi: 10.1053/j.gastro.2018.12.010. Epub 2018 Dec 19. PMID: 30578783; PMCID: PMC6409202.