•chest X-ray: lack of any significant abnormalities•laboratory findings: anti-islet cell antibodies at 160 Juvenile Diabetes Foundation units, anti-glutamic acid decarboxylase autoantibodies at 1779.41 U/mL, 10-fold exceeding the upper limit of normal titers of anti-tissue transglutaminase antibodies, anti-deamidated gliadin peptide antibodies, and anti-endomysial antibodies•diabetes mellitus type 1 and celiac disease diagnosis. Here, TGM2 is linked to type 1 diabetes mellitus.