Serological Screening for Celiac Disease and Gastrointestinal Absorption Disorders in Patients with Autoimmune Endocrine Diseases

Celiac disease (CD) accompanying autoimmune endocrine diseases (AED) is generally asymptomatic. This study aimed to evaluate the frequency of clinically overt or silent CD in patients diagnosed with autoimmune endocrinopathy and the clinical effects of silent CD in these endocrinopathies. The study included 166 patients with known or newly diagnosed mono-/polyglandular AED and 90 age- and gender-matched healthy controls. The patients were classified into four groups: type 1 diabetes mellitus (DM) (n=44), Hashimoto's thyroiditis (HT) (n=68), Addison's disease (AD) (n=17), and autoimmune polyglandular syndrome (APS) (n=37). All subjects were serologically screened for tissue transglutaminase antibody (tTG) IgA and IgG. In addition, to evaluate the possible systemic consequences of CD, serum parathormone (PTH), 25-hydroxicholecalsiferol (25-OH-Vit D), vitamin B12, folic acid, iron, iron-binding capacity (IBC), and ferritin levels were measured. In the total series, 193 (75.4%) individuals were females, and 63 (24.6%) were males. TTG IgA antibody positivity was found in 23 among 166 patients, while no positivity was encountered in the healthy control group. The highest rates of positive tTg IgA frequency were detected in AD, with 29.4% (5/17). Serum 25-OH-Vit D, vitamin B12, folic acid, iron, and ferritin levels were significantly lower in AEDs compared to controls (p<0.001), and the lowest these parameters were detected in patients with AD. The serologic CD prevalence is higher in autoimmune mono-/and polyglandular endocrine diseases than in the control group. The data support recommends regular screening for CD in all patients with AEDs.