Diagnostic dilemma in a patient with COVID vaccine-related thrombosis

ABSTRACT

Case Report While the COVID-19 pandemic killing millions world-wide, definitive therapy is not yet available. However, vaccines were shown to effectively reduce COVID-19 related mortality. Side effects of COVID vaccination include thrombosis. Most of the vaccine-related thrombosis took place after the Oxford-AstraZeneca and Johnson & Johnson vaccines. Our case, however, developed thrombosis after receiving the Moderna mRNA vaccine. A 62 y/o female with hypertension and paroxysmal atrial fibrillation had retroperitoneal hematoma thought to be due to an aneurysm posterior to the pancreatic head and underwent embolization. Following this, she developed bilateral pulmonary embolism (PE) secondary to iliac vein thrombosis which was thought to be a direct result of compression from the hematoma. She was started on anticoagulation (rivaroxaban) at that time and monitored closely for possible bleeding. Unfortunately, she stopped rivaroxaban after one month due to financial reasons. A year later, the patient presented to the hospital with chest tightness for 3 days, one week after she took her 2nd dose of Moderna vaccine. 2 days later, she started having left-sided chest tightness and dizziness. She has no family history of clotting disorder, recent surgery, and has no known malignancy. On admission, she was hemodynamically stable with normal oxygen saturation in room air. Blood work showed normal platelet count and coagulation panel. CT angiogram of the chest showed PE in the right middle lobe segmental branch without right ventricular strain. She did not have troponin elevation or EKG changes. Apixaban was initiated through a financial assistance program on discharge. Although vaccine-related thrombosis remains at the top of the differential diagnosis for our patient, a history of prior thromboembolic event a year earlier and lack of adherence to anticoagulation may have enhanced this lady's resurgence of thrombosis. Having a high degree of suspicion following COVID vaccination is always important to make an early diagnosis and prevent serious consequences of thromboembolism. It is possible that the immune-modulatory effects of the mRNA vaccines can enhance the recurrence of thrombosis in persons with previous history of the condition.