Immunochromatographic Sticks for Tissue Transglutaminase and Antigliadin Antibody Screening in Celiac Disease

Background & Aims: We investigated two 1-step immunochromatographic visual assays based on human recombinant tissue-transglutaminase (t-TG) as an alternative to enzyme-linked immunosorbent assays (ELISAs) for celiac disease (CD) screening. Methods: We used a tissue-transglutaminase (t-TG) stick, which detected immunoglobulin A/G (IgA/G) antibodies to t-TG, and a t-TG/antigliadin antibodies (AGA) stick, which detected IgA antibodies to both t-TG and AGA, as well as t-TG and AGA ELISAs, to determine t-TG and AGA antibodies in untreated celiac patients with subtotal villous atrophy. A total of 142 children (3 IgA-deficient sera) and 30 adults, and 140 controls (normal mucosa; 121 children and 19 adults), plus 23 sera from pediatric CD patients in remission were assayed. Results: For pediatric patients, with the t-TG stick we obtained a sensitivity of 97.1% and a specificity of 99.0%, and in adults, 83.3% and 100%, respectively. The t-TG/AGA stick displayed a sensitivity of 95.7% and a specificity of 99.0% for t-TG and a sensitivity of 89.2% and a specificity of 95.8% for AGA in children, and a sensitivity of 80% and a specificity of 100% for t-TG and a sensitivity of 83.3% and a specificity of 100% for AGA in adults. Results were comparable with the corresponding ELISAs. Conclusions: The 2 visual assays are efficient for CD screening as an alternative to ELISAs. They are simple to handle and to interpret. By the combined use of the 2 sticks, IgA-deficient patients can be identified as positive in the t-TG (IgG/A) but negative in the t-TG/AGA (IgA) stick.