ESPE Abstracts

Backgroud: Recent studies have revealed the presence of zinc and the expression of zinc transporter (ZnT) family members in most endocrine cell types. It was demonstrated that ZnT family plays an important role in the synthesis and secretion of many hormones. Moreover, recently ZnT8 was described as a newly islet autoantigen in type 1 diabetes.

Material and methods: The study was performed in the group consisting of patients with 44 Graves’ disease (GD) (mean age, 14.4±3.1), 66 Hashimoto’s thyroiditis (HT) (mean age, 13.0±3.7), 166 with T1DM (mean age, 12.4±4.1), 36 with both T1DM and GD or HT (mean age, 13.2±4.3), and 58 healthy controls (mean age, 13.3±3.5). GAD, IA-2, IAA, ZnT8, 21OH antibodies’ concentration were evaluated in the peripheral blood.

Results: ZnT8 Ab was found in 4 patients (9.1%) with GD while 4 patients (9.1%) were positive for GAD Ab, two patients (4.5%) were positive for IA-2 Ab and one patient (2.2%) was positive for IAA. Of these, one GD patient was positive for all four diabetes associated antibodies and one was positive for GAD Ab and ZnT8 Ab, two GD patients (4.5%) were positive for ZnT8 Ab only. In the case of HT patients, 6 (9.1%) were positive for ZnT8 Ab, while 4 patients (6.1%) were positive for GAD Ab, 4 (6.1%) were positive for IA-2 Ab and 3 (4.5%) were positive for IAA Ab. Of these, one HT patient was positive for all four diabetes associated antibodies, 2 had 3 diabetes associated antibodies (ZnT8 Ab, IA-2 Ab, GAD Ab or IAA) and one had 2 diabetes associated antibodies (GAD Ab and IAA), 3 HT patients (4.5%) were positive for ZnT8 Ab only.

Conclusions: These results show the presence of ZnT8 autoantibodies not only in patients with type 1 diabetes mellitus but also with Graves’ disease and Hashimoto’s thyroiditis. Further longitudinal studies in a large cohort are necessary.