Container: Clotted

Sample type: Clotted blood

Test name: HIT a.k.a. Heparin Induced Thrombocytopenia PF4 antibodies

Condition / Indication: Requested when there is a high clinical suspicion of HIT. This is usually indicated by the 4T score. HIT typically develops 4 to 14 days following treatment with unfractionated heparin (UFH), however, low molecular weight heparin (LMWH), or, more rarely, fondaparinux have been shown to also cause HIT. In HIT heparin-dependent IgG antibodies bind to platelet factor 4 and activates platelets resulting in thrombocytopenia and/or thrombosis.

Special precautions & notes: Requesting for HIT is now available on ICE. If urgent please phone ahead of your request. An example 4T score calculator can be found below.

Container: Clotted

Referred outside NBT for analysis? Yes

Discipline: Haematology

Turnaround time: 1 day for urgent requests otherwise 5 days.


Referral location: NHS Blood and Transplant, Filton, North Bristol Park, Northway, Filton, Bristol BS34 7QH