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Covid-19 Primary Care Resources


Vaccine-induced immune thrombocytopenia and thrombosis (VITT)



Signs, symptoms, when to refer and when to investigate in primary care

This information is sourced from the MHRA, Pulse today the RCGP and NICE:

Current Evidence on Vaccine-induced immune thrombocytopenia and thrombosis (VITT)

VITT is rare, with an incidence after first dose of Covid-19 vaccine of 14.2 per million doses

The MHRA is currently conducting a detailed review of suspected cases of VITT following Covid-19 vaccination to understand the risk factors for developing this condition

Cerebral venous sinus thrombosis (CVST) is the most common site of thrombosis. The remaining cases have affected a range of sites such as the splanchnic system, heart, lungs or limbs

Identifying suspected VITT

The MHRA have advised that anyone who has symptoms which develop four days or more after vaccination to seek medical attention

Red flags
• New onset of severe headache, which is getting worse and does not respond to simple painkillers
• An unusual headache that seems worse when lying down or bending over, or accompanied by blurred vision, nausea and vomiting, difficulty with speech, weakness, drowsiness or seizures
• Abnormalities of eye movements
• New onset of unexplained pinprick bruising or bleeding
• Shortness of breath, chest pain, leg swelling or persistent abdominal pain

Investigations and Diagnosis

Refer unwell patients immediately to A&E

The RCGP and NICE advise that a normal FBC, D dimer and fibrinogen may be used to exclude thromboembolism with thrombocytopaenia in primary care but only if the patient is not acutely unwell and the blood results with be available, reviewed and acted upon the same day

A confirmed diagnosis of CSVT requires CT or MRI venography, or cerebral angiography

Written by Dr Poppy Freeman