ADVIA Centaur Anti-Thyroglobulin II (aTgII)

The ADVIA Centaur Anti-Thyroglobulin II (aTgII) assay is an in vitro diagnostic test that quantitatively measures autoantibodies against thyroglobulin in human serum and plasma samples using the ADVIA Centaur XP system. It is used as an aid in diagnosing autoimmune thyroiditis and Graves' disease, in conjunction with clinical assessment.

The candidate device is a 1-step sandwich chemiluminescence immunoassay with a measuring interval of 1.1–1000 IU/mL and a cut-off of ≤4.5 IU/mL, using human thyroglobulin labeled with acridinium ester as the detection antibody and biotinylated human thyroglobulin on streptavidin-coated paramagnetic particles as the capture antibody. The predicate device is a 2-step sandwich assay with a broader measuring interval (0.9–2500 IU/mL) and cut-off of ≤4.0 IU/mL, using alkaline phosphatase conjugate detection. Both use chemiluminescence technology and accept the same sample types (serum and plasma).

CLSI Document EP28-A3c (reference intervals), EP12-A2 (clinical performance), EP17-A2 (detection limits), EP05-A3 (precision and reproducibility), EP09c-A3 (specimen equivalence), EP07-ed3 and EP37-ed1 (interference), EP06 ED2:2020 (linearity).

The ADVIA Centaur aTgII assay is substantially equivalent to the Beckman Coulter Access Thyroglobulin Antibody II (TgAbII) predicate device (K112933) based on comparable intended use, quantitative measurement principle, identical sample types, equivalent clinical sensitivity and specificity (combined sensitivity 34.3%, specificity 86.1%), high agreement with the comparative assay (96.7% positive predictive agreement, 92.2% negative predictive agreement), and demonstrated performance across precision, reproducibility, linearity, and interference testing.