Real-world Evaluation of a Novel Automated Method for Measuring ADAMTS13 Activity Using the Ceveron® S100 Analyzer

Introduction: Thrombotic thrombocytopenic purpura (TTP) is a thrombotic microangiopathy characterized by a severe functional deficiency of ADAMTS13. Measuring ADAMTS13 activity is crucial for diagnosing TTP (<10 IU/dL), monitoring treatments, and detecting relapses (<20 IU/dL). The Technofluor® assay allows a rapid ADAMTS13 activity measurement using the CEVERON® s100 analyzer. This study aims to evaluate the analytical and clinical performance of this new test under real-world conditions.

Materials And Methods: ADAMTS13 activity was measured using two fluorometric methods: the Technofluor® ADAMTS13 activity on the CEVERON® s100 (Technoclone, Austria) and our reference FRETS-VWF73 method, in plasma samples collected under real-life conditions (01/12/2024-04/04/2024) and retrospectively selected samples from our biobank. The analytical and clinical performance of the new test was assessed, focusing on the critical low levels (<30 IU/dL).

Results: Four hundred samples were tested under real-world conditions and 100 others tested retrospectively. The Technofluor® assay showed excellent analytical performance, with a detection limit of 0.1 IU/dL, repeatability CV <11%, and reproducibility CV of 6.1% (high level [90 IU/dL]) and 7.5% (low level [40 IU/dL]). Clinical performances were strong at diagnosis (threshold: 10 IU/dL; sensitivity and positive predictive value: 1.0) and during the follow-up (threshold: 20 IU/dL; specificity: 1.0 [95% CI: 0.99;1.00], positive predictive value: 0.96 [0.90;1.01]; negative predictive value: 0.98 [0.97;1.00]). No analytical interference was observed.

Conclusion: The Technofluor® assay on the CEVERON® s100 is a fast, reliable method for measuring ADAMTS13 activity, proving effectiveness for diagnosis and monitoring of TTP patients. However, it remains crucial to interpret ADAMTS13 activity measurement with clinical context to ensure accurate diagnosis and management.