Clinical and economic implications of false-positive heparin-induced thrombocytopenia immunoassays: utility of the 4T score.


Journal

Blood coagulation & fibrinolysis : an international journal in haemostasis and thrombosis
ISSN: 1473-5733
Titre abrégé: Blood Coagul Fibrinolysis
Pays: England
ID NLM: 9102551

Informations de publication

Date de publication:
05 Jun 2024
Historique:
medline: 14 6 2024
pubmed: 14 6 2024
entrez: 14 6 2024
Statut: aheadofprint

Résumé

Heparin-induced thrombocytopenia (HIT) is a prothrombotic condition induced by platelet-activating IgG antibodies that recognize PF4/heparin complexes. Diagnosis of HIT relies on enzyme immunologic assays (EIAs) and functional assays [serotonin release assay (SRA)]. Our institution uses a latex immunoturbidimetric assay (LIA), which has shown a positive-predictive value (PPV) of 55.6%, and a negative-predictive value (NPV) of 99.7%. The low PPV of EIAs/LIAs, in combination with the clinical delay in obtaining results of a SRA, commonly leads to a false-positive diagnosis of HIT and inappropriate treatment. We performed a single-institution retrospective study at a large tertiary center to assess patient management decisions and economic costs following a false-positive HIT (LIA) test. This study found an 89.5% incidence of false-positive HIT (LIA) tests. 97.4% of patients underwent anticoagulation changes. 69.6% of patients were switched to argatroban. Of patients with a false-positive HIT immunoassay (LIA), 42 (40.7%) patients were on a prophylactic dose of anticoagulation at the time of HIT (LIA) positivity, of which 22 (52.4%) were switched to full anticoagulation with either argatroban or fondaparinux. Of the 22 patients switched to full anticoagulation, 15 (68%) had low-probability 4T scores. Seven (8.8%) of patients had bleeding events after HIT (LIA) positivity. All seven patients were switched to argatroban from a full-dose heparin anticoagulation. Five of the seven patients were considered major bleeds. Utilization of argatroban incurred substantial costs, estimated at approximately $73 000 for false-positive HIT cases. False-positive HIT (LIA) tests contribute to unwarranted anticoagulation changes, increased bleeding risks, and substantial healthcare costs. Incorporating the 4T score into diagnostic algorithms may help mitigate these risks by guiding appropriate clinical decisions. Future research should focus on refining diagnostic approaches and standardizing management strategies to improve patient outcomes and cost-effectiveness in HIT diagnosis and management.

Identifiants

pubmed: 38874904
doi: 10.1097/MBC.0000000000001314
pii: 00001721-990000000-00157
doi:

Types de publication

Journal Article

Langues

eng

Sous-ensembles de citation

IM

Informations de copyright

Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.

Références

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Auteurs

Bradley Dweck (B)

Baylor University Medical Center at Dallas.

Mallory Pane (M)

Baylor University Medical Center at Dallas.

Veronica Nguyen (V)

Texas A&M Medical School at Dallas, Dallas, Texas, USA.

Shalini Sharma (S)

Texas A&M Medical School at Dallas, Dallas, Texas, USA.

Alec Monhollen (A)

Texas A&M Medical School at Dallas, Dallas, Texas, USA.

Sankirthana Malireddy (S)

Texas A&M Medical School at Dallas, Dallas, Texas, USA.

Andrew Whiteley (A)

Baylor University Medical Center at Dallas.

Classifications MeSH