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Thank you for attending THSNA 2026. The virtual meeting is now closed.
Thank you for attending THSNA 2026. The virtual meeting is now closed.
Presentation Details
| Precision and Reproducibility of a New Automated Chemiluminescent Immunoassay for the Detection of Anti-Platelet Factor 4/Heparin (PF4/H) IgG Antibodies Niki Leonard, Kerrie Jaskal. Werfen, Bedford, MA, USA |
Abstract
Background Diagnosis and management of heparin-induced thrombocytopenia (HIT) depends on laboratory and clinical findings. IgG-specific chemiluminescent immunoassays (CLIA) offer high sensitivity and specificity for HIT diagnosis. Guidelines recommend following a positive immunoassay with a functional assay like the serotonin release assay (SRA). Due to limited SRA availability, patient management may rely on a pretest probability score (e.g., 4T) and immunoassay results. A new, fully automated, CLIA (HemosIL CL HIT-IgG(PF4-H) [CL HIT]) has been developed for the ACL TOP 970 CL instrument to determine the risk for HIT when used in conjunction with other laboratory and clinical findings. Precision and reproducibility for the new assay was determined in a two-part study. Objectives To establish precision and reproducibility for CL HIT. Methods In an internal precision study, five plasma samples spanning the CL HIT assay’s test range along with two quality control levels were tested in a 20x2x2 study design. This study was conducted using three lots of CL HIT on one ACL TOP 970 CL. An external reproducibility study was conducted in a multi-site study. Six plasma samples spanning the CL HIT assay’s test range along with two quality control levels were tested in a 5x2x3 study design on three lots of CL HIT. Ethics approval was obtained from the sites’ institutional review board. Results Table 1 shows the qualitative results of the precision study with the worst-performing lot showing repeatability and within-laboratory results near the established cut-off of CL HIT (1.00 U/mL) resulting at 3% CV and 6-7% CV, respectively. Table 2 shows the qualitative results of the reproducibility study pooling all three lot CL HIT lots from the three sites. Total reproducibility near the established cut-off of CL HIT (1.00 U/mL) resulted 8% CV. Conclusions CL HIT demonstrates low imprecision ensuring accurate results with very minimal variation from run to run, day to day, lot to lot, etc. CL HIT offers another option for laboratories expanding on-demand HIT antibody testing that targets clinically relevant IgG antibodies against PF4/H, supports confident clinical decisions, and has strong agreement with commercially available anti-PF4/H antibody and functional assays.
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No part of this publication may be reproduced, distributed, or transmitted in any form or by any means, including photocopying, recording, or other electronic or mechanical methods, without the prior written permission of the author.