Establishment of New Immunostatistical Equations for Diagnosis and Follow-Up of Gluten-Free Diet in Patients with Celiac Disease.

<b>Background and Objective:</b> Celiac disease (CD) is an autoimmune condition characterized by immune responses to gluten. The reported prevalence of CD has increased globally due to improved screening and diagnostic techniques, however, there is significant global variation in methods of diagnosis and follow-up. A new immunostatistical equation that determines the values of two types of antibodies using the total IgA test. <b>Materials and Methods:</b> Only 70 blood samples were taken from people who had celiac disease or were suspected of having it, with ages ranging from 5 to 40 years and they were separated into two groups. The first group contained 40 people of both sexes who had previously been diagnosed with celiac disease, while the second group included 30 individuals of both sexes, with ages ranging from 5 to 35 years, who were suspected of having celiac disease due to the appearance of some clinical symptoms. The control group also included 30 blood samples from healthy individuals of both sexes, with ages ranging from 5 to 40 years. Total IgA antibody tTG/IgA and DGP/IgA levels were estimated for all study samples. <b>Results:</b> By using a regression coefficient test the results showed the percentage of the effect of total IgA on tTG/IgA, DGP/IgA amounted to 11 and 25%, respectively, as shown by the value of the coefficient of clarifications (R²) in patients with CD. On the other hand, The percentage of the effect of total IgA on tTG/IgA and DGP/IgA amounted to 11, 14%, respectively, as shown by the value of the coefficient of clarifications (R²) in patients with suspected CD in p<u><</u>0.05. The results of the study were revealed and through the regression coefficient, four new immunostatistical equations were mathematically derived that give the value of tTG/IgA and DGP/IgA based solely on the total IgA test in the laboratory. <b>Conclusion:</b> By adopting one laboratory test which determines total IgA, the study concluded four new immunostatistical equations that will help academic researchers and attending physicians to diagnose celiac disease in addition to following up on patient's adherence to a gluten-free diet.