[Arterial thrombosis due to heparin induced thrombocytopenia]

Type II heparin induced thrombocytopenia (HIT) is a procoagulant disorder that is caused by IgG-antibodies against platelet factor 4 (PF4)-heparin (H) complex. Clotting tendency is also increased. This is characterized by a ≥ 50% decrease in platelet count between 5-10 days after exposure to unfractionated or low-molecular weight heparin.

A 49-year-old woman presented with neurological symptoms and pain in her right hand shortly after hospitalisation in Spain. She had an ischaemic CVA and arterial perfusion difficulties in her right arm due to a large thrombus in the aortic arch and some of its branches. She was treated with thrombolytic therapy and dalteparin. Based on initially mild thrombocytopenia that progressed rapidly after admission and her 7-day exposure to enoxaparin during the previous hospital admission, we diagnosed heparin induced thrombocytopenia (HIT) with arterial thrombosis.

It can be difficult to diagnose HIT. A clinical probability score based on clinical parameters and laboratory results is useful in this. Quick diagnosis and treatment are of great importance because of the high risk of complications.