Performance evaluation of heparin-induced platelet aggregation vs serotonin release assay

© The Author(s) 2023. Published by Oxford University Press on behalf of American Society for Clinical Pathology. All rights reserved. For permissions, please e-mail: journals.permissionsoup.com..

OBJECTIVES: Heparin-induced thrombocytopenia (HIT) is a rare but life-threatening condition that requires rapid diagnosis for proper management. Laboratory testing should only be performed on patients with intermediate- or high-risk pretest probability. The platelet factor 4 (PF4) enzyme-linked immunosorbent assay (ELISA) is the screening test that should be confirmed by higher specificity testing such as the heparin-induced platelet aggregation (HIPA) or the serotonin release assay (SRA). This study aims to evaluate the performance of the HIPA in comparison to the SRA, establish cutoffs of the PF4 ELISA to predict positivity for HIPA/SRA, and study the mortality rate between patients with suspected HIT confirmed as HIT positive vs negative.

METHODS: All positive PF4 ELISA cases with confirmatory HIPA and SRA testing were included. As the SRA was considered the gold standard, the HIPA performance was evaluated in comparison to SRA before and after the implementation of a new standardized interpretation guide in 2022. The mortality of these cases was also documented by chart reviews.

RESULTS: In total, 232 cases with positive or indeterminate anti-PF4 IgG ELISA had confirmatory testing with HIPA and SRA. The sensitivity of the HIPA improved from 55.4% in 2018 to 2021 to 73.8% in 2022. The specificity remained similarly high in 2018 to 2021 vs 2022 (94.9% vs 87.5%). The negative predictive value (NPV) improved in 2022. The PF4 optical density cutoff to predict the positivity of SRA was 0.85 vs 1.47 to predict the positivity of HIPA but decreased to 0.83 when combining HIPA and/or SRA. There was no significant difference in mortality between patients with suspected HIT confirmed positive vs negative.

CONCLUSIONS: Although the HIPA has a lower sensitivity than the SRA, the new standardized interpretation guide improved its sensitivity and NPV in 2022. Future improvements are needed to use the HIPA as a stand-alone confirmatory test with the goal to shorten hospital length of stay and expedite proper anticoagulation management.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:161

Enthalten in:

American journal of clinical pathology - 161(2024), 2 vom: 01. Feb., Seite 122-129

Sprache:

Englisch

Beteiligte Personen:

Barouqa, Mohammad [VerfasserIn]
Matta, Milad [VerfasserIn]
Reyes-Gil, Morayma [VerfasserIn]

Links:

Volltext

Themen:

333DO1RDJY
9005-49-6
Anticoagulants
Heparin
Heparin-induced platelet aggregation
Heparin-induced thrombocytopenia
Journal Article
Platelet factor 4
Serotonin
Serotonin release assay

Anmerkungen:

Date Completed 02.02.2024

Date Revised 02.02.2024

published: Print

Citation Status MEDLINE

doi:

10.1093/ajcp/aqad117

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM364280174