Study of the diagnostic efficiency of anti-ZnT8 autoantibodies for type 1 diabetes in pediatric patients.

Abstract

Objective: Zinc transporter 8 autoantibodies (ZNt8A) are 1 of the 4 main autoantibodies used for the diagnosis of type 1 diabetes (T1D), with glutamic acid decarboxylase autoantibodies (GADA), islet antigen-2 autoantibodies (IA-2A), and insulin autoantibodies (IAA). The objective of this study is to evaluate the diagnostic efficiency of these autoantibodies for the diagnosis of T1D in pediatric patients.

Methods: A retrospective analysis of patients under 16 years of age with suspected T1D was made between June 2020 and January 2021. A total of 80 patients were included in the study, with 1 sample per patient. Subjects were classified according to diagnosis.

Results: Of the subjects included in the study, 50 developed T1D. The diagnostic efficacy was IA-2A (cutoff ≥ 28 U/L) sensitivity 0.26 (95% CI: 0.14-0.38) and specificity 0.97 (95% CI: 0.79-1.0); GADA (cutoff ≥ 17 U/mL) sensitivity 0.40 (95% CI: 0.26-0.54) and specificity 0.87 (95% CI: 0.75-0.99); ZnT8A (cut off ≥ 15 U/L) sensitivity 0.62 (95% CI: 0.49-0.75) and specificity 0.97 (95% CI: 0.90-1.0). ZnT8A obtained the most significantly global diagnostic accuracy (0.75), and GADA with ZnT8A showed the highest correlation.

Conclusion: The results obtained indicate a higher efficiency of anti-ZnT8 autoantibodies for the diagnosis of T1D in pediatric patients. Clinical efficiency of diabetic autoantibodies is method and assay dependent and influences combined diagnostic strategies.