Platelet factor 4 immune disease: medical emergencies that look like heparin-induced thrombocytopenia

Ashwini Bennett; Phil Y Choi; Chee Wee Tan

doi:10.1111/imj.16546

Platelet factor 4 immune disease: medical emergencies that look like heparin-induced thrombocytopenia

Intern Med J. 2024 Nov 20. doi: 10.1111/imj.16546. Online ahead of print.

Authors

Ashwini Bennett^#^{1

2}, Phil Y Choi^#^{3

4}, Chee Wee Tan^#^{5

6

7}

Affiliations

¹ Department of Haematology, Monash Health, Melbourne, Victoria, Australia.
² Monash University, Melbourne, Victoria, Australia.
³ Department of Haematology, Canberra Health Services, Canberra, Australian Capital Territory, Australia.
⁴ John Curtin School of Medical Research, Australian National University, Canberra, Australian Capital Territory, Australia.
⁵ Department of Haematology, Royal Adelaide Hospital, Central Adelaide Local Health Network, Adelaide, South Australia, Australia.
⁶ SA Pathology, Adelaide, South Australia, Australia.
⁷ Department of Medicine, Faculty of Health and Medical Sciences, University of Adelaide, Adelaide, South Australia, Australia.

^# Contributed equally.

PMID: 39568125
DOI: 10.1111/imj.16546

Abstract

Heparin-induced thrombocytopenia (HIT) is a serious adverse reaction to heparin. Other HIT-like syndromes are increasingly recognised, mediated by antibodies binding to platelet factor 4, with or without identifiable polyanions. The history of heparin exposure is atypical for classical HIT and standard HIT laboratory tests may be negative. This manuscript describes subtypes of HIT-like syndromes and highlights practical tips for diagnosis and therapy.

Keywords: anti‐coagulation; autoimmune; heparin; platelet factor 4; thrombocytopenia; thrombosis.