Improving the diagnostic approach to type I diabetes: the introduction of anti-zinc transporter protein autoantibodies (ZnT8A) (835.15)

Aim of the study. To evaluate the prevalence and persistence of ZnT8A, in a cohort of Pediatric diabetic patients, to assess reliability and relationship with other T1DM diagnostic markers. Methods. Sera from 97 T1DM pediatric patients (53.6% M/46.4% F, age 11.1 ± 3.9 yrs), and 112 controls (51.8% M/48.2% F, age 9.6 ± 4.9 yrs; with no T1D or family history of autoimmune diseases) were analyzed for IgG ZnT8, GADA, IA2A and AIA by ELISA, and for IgG Islet Cell Antibodies (ICA) by an indirect immunofluorescence test on cryostat primate’s pancreas. Results. ZnT8A (cut-off 蠅 15 UA/ml) were present in 54.6% (53/97) T1DM patients (in two cases as the unique autoantibody) vs 97.3% (3/112) controls (p<0.0001). ZnT8A prevalence decreases among onset (25/40, 62.5%) and follow-up patients with 5 or more years of disease (12/29, 41.3%). The prevalence of ICA at disease onset was 33.3% compared to 66.7% for GADA, 73.3% for IA2A, 73.3% for ZnT8A and 6% for AIA. Conclusions. The sensitivity (54.6%) and specificity (97.3%...