Diagnosis of Celiac Disease in Pediatric Patients

Diagnostic Approach

The European Society for Pediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN) recommends that children with suspected celiac disease should start with tissue transglutaminase IgA (tTG-IgA) testing along with total IgA levels, and in cases with tTG-IgA ≥10 times the upper limit of normal, EMA-IgA positive, and HLA-DQ2/DQ8 positive, the diagnosis can be confirmed without intestinal biopsy 1, 2
The American Gastroenterological Association suggests that tTG-IgA has a sensitivity of 97.7% and a specificity of 70.2% in children 3, 4
The patient should consume a gluten-containing diet (at least 10g per day for 6-8 weeks) before testing, as gluten elimination leads to false-negative results 2

The American College of Gastroenterology recommends that anti-endomysial IgA (EMA-IgA) antibodies should be used as a confirmatory test when tTG-IgA is elevated, with an excellent specificity of 93.8% in children 3, 1
In children under 2 years of age, combining tTG-IgA with deamidated gliadin peptides IgG and IgA improves sensitivity 1, 2

The ESPGHAN 2012 criteria state that symptomatic children can avoid intestinal biopsy if they meet all the following criteria: tTG-IgA ≥10 times the upper limit of normal, EMA-IgA positive, HLA-DQ2/DQ8 positive, and symptoms compatible with malabsorption 5, 1

The American Academy of Pediatrics recommends screening for celiac disease in children with type 1 diabetes mellitus (prevalence 5-10%) at diagnosis, after 2 years, and after 5 years 6
First-degree relatives of patients with celiac disease (risk 7.5%) should also be screened 7, 8
Children with Down syndrome or Turner syndrome should be screened for celiac disease 7, 8, 1

The HLA-DQ2/DQ8 test has a negative predictive value of >99%, and the absence of both alleles virtually excludes celiac disease 1, 2
The HLA test should be used when celiac disease is strongly suspected despite negative serology 1

tTG-IgA >100 units or EMA >1:1280 are highly specific (>98%) for Marsh 3a or higher lesions 1, 2

Do not start a gluten-free diet before completing diagnostic evaluation, as this makes subsequent tests unreliable 2
Do not rely solely on symptoms, as height and weight are not reliable predictors of celiac disease 5, 2

Total IgA levels must be measured simultaneously with tTG-IgA to identify IgA deficiency, which affects approximately 2-3% of celiac patients and causes false-negative IgA-based test results, as recommended by the Gastroenterology society 9

In children with confirmed IgA deficiency, IgG-based tests such as IgG deamidated gliadin peptide (DGP-IgG) and IgG tissue transglutaminase (tTG-IgG) should be used, as suggested by the Gastroenterology society 9

Biopsy remains necessary in adults and in children who do not meet the strict biopsy-avoidance criteria, according to the Gastroenterology society 9