Diagnosis of gluten-related enteropathy in a newborn: how and when?

Aim: To analyze the development of gliadin-specific immune responses in children with a genetic risk for CD and to determine whether these could be detected before the clinical onset of the disease by using immunological tests. Background: Clinical manifestations of celiac disease (CD) in the first year of life is uncommon, which is due to the suboptimal sensitivity of tissue transglutaminase IgA antibodies (tTG-IgA) at this age and other possible causes of malabsorption in infants. The development of Deamidate gliadin peptide-specific antibodies (in particular DGP-IgG) in young children was poorly considered in the CD diagnosis. Methods: We conducted a retrospective cross-sectional study on children between one month and forty-eight months of life, which performed in our health center from 2016 to 2018. Three hundred and fifty children were selected according to strict inclusion criteria: positive for HLA-DQA1 and DQB1 alleles, positive anti tTG-IgA/IgG and/or positive DGP-IgG/IgA. Eighty-two children were selected and divided into two different groups of patients: Group one (forty newborns under twenty-four months of life) and Group two (children from twenty-five months to 48 months of life). Results: Anti-DGP-IgG antibodies precede anti tTG-IgA seroconversion in children under two years in 80% of cases. Anti-DGP-IgG positive patients had milder symptomatic forms of CD than anti tTG-IgA positive children, characterized by gastrointestinal symptoms in the presence of normal growth, normal serum iron, and low MCH level. At tTG-IgA seroconversion, children present gastrointestinal clinical forms associated with impaired growth. The combined use of tTG-IgA and DGP-IgG antibodies upgrade the diagnostic sensitivity from 50% to 92%. Conclusion: Anti-DGP-IgG antibodies precede tTG-IgA seroconversion in newborns and identified two distinct clinical phenotypes. At this point, if you wanted to test your newborn patients for CD serology, how would you proceed?