PB0323 - Hemorrhagic clinic in an immune-mediated and prothrombotic entity: heparin-induced thrombocytopenia (HIT). Case report

Background: Heparin-induced thrombocytopenia (HIT) is a rare immune-mediated adverse reaction. Bleeding is rare and is typically associated with thromboembolic complications.

Aims: The purpose is to analyze a case of a 65-year-old female patient, who experiences both possible complications secondary to a picture of HIT: pulmonary thromboembolism and extensive intracranial bleeding.

Methods: On the subject of a case at the Central University Hospital of Asturias in 2021. HIT test is performed by automated chemiluminescience that detects the existence of IgG-type antibodies

Results: Female patient with no medical history. After a hip surgical intervention, it was started low molecular weight heparines (LMWH) at prophylactic doses.
Two weeks later, she started with dyspnea and pleuritic pain. Analytically it was observed elevation of D-dimer. An angio-CT scan was performed that described an acute pulmonary thromboembolism in the middle lobe and right pulmonary artery. In this moment it was increased LMWH at therapeutic doses. Subsequently in successive analytical controls, there were a progressive thrombopenia up to 56,000 / mm3 (Graph 1), without anemia and with normal smears.
With this count of platelets she experienced a sudden neurological picture with disorientation, aphasia, and hemiparesis and with a radiological finding of an extensive left hemispheric hematoma, not candidate for surgical intervention. The transfusion yield was null. Therefore, due to the high suspicion, a HIT test was requested, which was positive and a high titer (IgG of 5.83U / ml), stopping the transfusion support. The evolution was poor and in a few hours the patient died.

Conclusion(s): In immune-mediated pathologies, the possibility of overlapping and / or transformation of some complications into others must be taken into account. It is essential to suspect this entity in patients with thrombopenia and with a history of onset of LMWH 5-10 days before or immediately if they received it in the previous 100 days.