Transient acquired factor XII deficiency associated with moderately severe Covid-19 pneumonia

• Murray, Nigel P.

• Factor XII Deficiency

The case report demonstrates the importance of investigating alternative causes of a prolonged APTT in patients with Covid-19. Although Covid-19 is associated with thrombotic complications it is possible that immune dys-regulation associated with SARS-CoV-2 may lead to other coagulation factor inhibitors and a hemorrhagic tendency. Clinical decisions on anticoagulant treatment may be influenced by the APTT and modified in patients with Covid-19. Management of these cases requires the clinical acumen to balance the potential for haemorrhagic and thrombotic complications of SARS-CoV-2 infection. The abnormalidades in the coagulation tests may persist long after clinical remission and resolution of inflammatory markers.