Biomed Pap Med Fac Univ Palacky Olomouc Czech Repub. X:X | DOI: 10.5507/bp.2026.032

Consistent dietary adherence in children and adolescents with celiac disease reflected in anti-tissue transglutaminase IgA and IgG: through diagnostic advancements and epidemiological challenges

Maria Veghova Velganova, Milos Geryk Osika, Eva Karaskova, Jana Volejnikova

Department of Pediatrics, Faculty of Medicine and Dentistry, Palacky University Olomouc and University Hospital Olomouc, Olomouc, Czech Republic

Background and Purpose. Recent ESPGHAN guidelines permit the omission of duodenal biopsies in the diagnosis of celiac disease (CeD) in children with tTG-IgA≥10× upper limit of normal, regardless of clinical symptoms. This non-invasive approach may compromise dietary adherence through underestimating disease severity and questioning the diagnosis by families. We monitored serologic response in biopsy-based vs. no-biopsy cohorts using both tTG-IgA and tTG-IgG. A second aim was to investigate subjective and objective factors associated with dietary adherence, including during the period of the COVID restrictions.

Methods: Between 2020-2025, 190 children and adolescents with CeD were followed according to ESPGHAN guidelines. Biopsy-based and no-biopsy cohorts were compared in terms of clinical and demographic factors, laboratory results and dietary adherence. A targeted COVID-19 questionnaire was completed by 159 families.

Results: tTG-IgA levels normalized within 6 months in 55% of patients and after 12 months in 89%. tTG-IgG titers showed similar dynamics, with slightly faster early decline (74% normalized at 6 months), and were indispensable in 4 children (2.1%) with IgA deficiency. Antibody decline was comparable for the biopsy and no-biopsy groups. Only 13% of children exhibited nonadherence, mostly as a single episode. The no-biopsy group had a statistically higher incidence of anemia. The COVID-19 disease course was predominantly mild (94%), with gastrointestinal complications in 3 cases. The perceived impact of COVID-19-related lockdown on dietary adherence was self-reported as neutral in 65% and positive in 26% of families.

Conclusions: The no-biopsy approach sustained excellent antibody normalization rates, as measured by both tTG-IgA and tTG-IgG. Nonadherence was rare and mostly associated with adolescence, peer influence, challenged family/social structure, limited parental supervision, poor choice of school meals, and comorbidities. The importance of targeted educational interventions and follow-up is emphasized.

Keywords: biopsy, celiac disease, children, COVID-19, dietary adherence, tissue transglutaminase antibodies

Received: September 11, 2026; Revised: October 7, 2026; Accepted: October 23, 2026; Prepublished online: November 3, 2026