title: Evaluation of a new nanoparticle-based lateral-flow immunoassay for the exclusion of heparin-induced thrombocytopenia (HIT).
abstract: Heparin-induced thrombocytopenia (HIT) is an adverse complication of heparin caused by HIT antibodies (abs) that recognise platelet factor 4-heparin (PF4/hep) complexes. Several laboratory tests are available for the confirmation and/or refutation of HIT. A reliable and rapid single-sample test is still pending. It was the objective of this study to evaluate a new lateral-flow immunoassay based on nanoparticle technology. A cohort of 452 surgical and medical patients suspected of having HIT was evaluated. All samples were tested in two IgG-specific ELISAs, in a particle gel immunoassay (PaGIA) and in a newly developed lateral-flow immunoassay (LFI-HIT) as well as in a functional test (HIPA). Clinical pre-test probability was determined using 4T's score. Platelet-activating antibodies were present in 34/452 patients, all of whom had intermediate to high clinical probability. PF4/hep abs were detected in 79, 87, 86, and 63 sera using the four different immunoassays. The negative predictive values (NPV) were 100% for both ELISA tests and LFI-HIT but only 99.2% for PaGIA. There were less false positives (n=29) in the LFI-HIT compared to any other test. Additionally, significantly less time was required to perform LFI-HIT than to perform the other immunoassays. In conclusion, a newly developed lateral-flow assay, LFI-HIT, was capable of identifying all HIT patients in a cohort in a short period of time. Beside an NPV of 100%, the rate of false-positive signals is significantly lower with LFI-HIT than with other immunoassay(s). These performance characteristics suggest a high potency in reducing the risk and costs in patients suspected of having HIT.
authors: Institute for Clinical Immunology and Transfusion Medicine, Justus Liebig University, Langhansstr. 7, 35392 Giessen, Germany. ulrich.sachs@med.uni-giessen.de
authors: Ulrich J
authors: UJ
authors: Sachs
authors: Jakob
authors: J
authors: von Hesberg
authors: Sentot
authors: S
authors: Santoso
authors: Gregor
authors: G
authors: Bein
authors: Tamam
authors: T
authors: Bakchoul
mesh_terms: D000906:Antibodies / Q000097:blood*; D000936:Antigen-Antibody Complex / Q000276:immunology; D003362:Cost-Benefit Analysis; D006493:Heparin / Q000008:administration & dosage / Q000009:adverse effects*; D006801:Humans; D007118:Immunoassay; D053758:Nanoparticles; D010978:Platelet Factor 4 / Q000378:metabolism; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D013921:Thrombocytopenia / Q000097:blood / Q000139:chemically induced / Q000175:diagnosis*; D013997:Time Factors
chemical_list: D000906:Antibodies; D000936:Antigen-Antibody Complex; D010978:Platelet Factor 4; D006493:Heparin