P-478: Autoimmune thyroid disease at the onset of type 1 diabetes in Vietnamese children and adolescents
L T H Hai, V T Thao, C T B Ngoc, N T Ha, N N Khanh, N T Hang, B P Thao, D T K Giang, D T T Huyen, B T Xuan, V C DungAbstract
Introduction
Type 1 diabetes (T1D) is frequently associated with other autoimmune conditions, among which autoimmune thyroid disease (AITD) is the most common. However, data on the prevalence of AITD at the onset of T1D in children, particularly in low- and middle- income settings such as Vietnam, remain limited.
Objectives
To identify the prevalence of autoimmune thyroid disease at the onset of type 1 diabetes in Vietnamese children and adolescents.
Methods
This retrospective, hospital- based study was conducted at Vietnam National Children’s Hospital from January 2024 to December 2025. A total of 109 children and adolescents aged 0- 18 years with newly diagnosed T1D and positive pancreatic autoantibodies were included. Clinical and laboratory data at diagnosis were obtained from medical records. Thyroid assessment included serum thyroid- stimulating hormone (TSH), free thyroxine (fT4), and thyroid autoantibodies (anti- TPO and/or anti- Tg). AITD was defined as the presence of thyroid autoimmunity with or without thyroid dysfunction.
Results
Among 109 children with newly diagnosed T1D, autoimmune thyroid disease was identified in 15 (13.8%) patients. Euthyroid autoimmune thyroiditis was the most common presentation (11/109, 10.1%), followed by autoimmune hyperthyroidism (3/109, 2.8%) and autoimmune hypothyroidism (1/109, 0.9%). There was no significant difference in the prevalence of thyroid abnormalities between males and females (p > 0.05).
Conclusions
Autoimmune thyroid disease is a relatively common comorbidity at the onset of T1D in children and adolescents. These findings support routine screening for thyroid autoimmunity at diagnosis to enable early detection and appropriate management.