Predictors of celiac disease in patients with type 1 diabetes and positive tissue transglutaminase immunoglobulin A.

Objectives: Identify clinical and serologic features that more accurately predict a diagnosis of celiac disease (CD) in children with type 1 diabetes mellitus (T1DM), particularly focusing on the degree of elevation of tissue transglutaminase immunoglobulin A (TTG IgA) and dilution of positive endomysial antibody (EMA).

Methods: We performed a single-center retrospective review of patients with T1DM who underwent endoscopy from 2016 to 2022 for evaluation of CD. We compared demographic, anthropometric, and laboratory data as well as symptoms and endoscopy findings for subjects with and without CD.

Results: Of 123 subjects who underwent esophagogastroduodenoscopy, 74 (60%) were diagnosed with CD. Univariate logistic regression analysis revealed the factors associated with CD were degree of TTG IgA elevation, EMA positivity, and degree of EMA dilution. For every 10-fold increase in TTG IgA, there was a 4.7× increased risk of CD. TTG IgA ≥10 times the upper limit of normal (ULN) provided a positive predictive value (PPV) of 85% (confidence interval [CI]: [0.76-92]) in all subjects and 91% in asymptomatic subjects (CI: [0.75-0.98]). Of 66 subjects with EMA data, 41 (62%) were positive and 32 had CD (PPV = 0.78). Of 12 asymptomatic subjects with positive EMA, eight had CD (PPV = 0.67). For subjects with EMA ≥ 1:80, all were diagnosed with CD, and all had TTG IgA ≥10 times the ULN.

Conclusions: Among patients with T1DM, symptoms, adjunct labs, and anthropometrics do not help predict CD, but the degree of elevation of TTG IgA and dilution of a positive EMA result do.