Thrombotic thrombocytopenic purpura (TTP) is a potentially life-threatening consumptive coagulopathy requiring emergent diagnosis and timely treatment. It is characterized by microangiopathic hemolytic anemia and thrombocytopenia with the development of microthrombi caused by inherited or acquired deficiency of the von Willebrand factor-cleaving protease ADAMTS13 and resulting end-organ damage. Most of the cases are the result of acquired deficiency of ADAMTS13, for which the exact etiology is unknown but reported to be related to various autoimmune disorders, infections, and medications. Our case report features of a patient with a history of idiopathic thrombocytopenic purpura and thrombotic thrombocytopenic purpura, who developed a recurrence of TTP 5 days after his first dose of the mRNA Coronavirus disease 2019 (COVID-19) vaccine (mRNA-1273 vaccine) in the setting of recent COVID-19. The close temporal association between vaccine administration, recent COVID-19, and relapse of remitted TTP raises concern for an enhanced immune reaction to COVID-19 vaccine in the setting of recent COVID-19 and underlying autoimmune disease. The association is not absolute, but given the novelty of COVID-19 and the mRNA COVID-19 vaccine and the relapse timing, it leads us to pose this hypothesis. Vaccine distribution to a larger and more diverse population will allow for an increased rate of adverse event reporting. This case report exemplifies potential safety issues that may be encountered with new vaccine administration in patients with recent COVID-19 and underlying autoimmune disease. There are no specific recommendations for COVID-19 vaccine administration in such patients.

Aim: As the novel coronavirus disease 2019 (COVID-19) pandemic impacts the global healthcare system, evolving data show increased frequency of arterial and venous thromboembolism among patients with COVID-19 infection. Aortic thrombus is a rare thrombotic event with a wide spectrum of clinical manifestations and potential catastrophic complications. This study aimed to elucidate the clinical manifestations, diagnosis and treatment dilemmas of aortic thrombus with COVID-19 infection and raise awareness among frontline medical providers. Aortic thrombosis is rare, but if not considered early in the course of COVID-19 infection, the data suggest that the diagnosis will probably not be made until potentially serious complications arise. Methods: Literature review was conducted between November 1, 2019, and November 14, 2020, on PubMed and Embase to identify publications regarding aortic thrombosis among COVID-19 cases. Results: Most of the patients were male with a median age of 67 years, and had comorbidities (most commonly hypertension, dyslipidemia and diabetes mellitus). In our study, underlying atherosclerosis, a common risk factor for aortic thrombus, was identified among 56% of the patients. Aortic thrombus was symptomatic in 62% of these patients and most commonly manifested itself as acute limb ischemia (46%), whereas 30% of cases were found incidentally during the investigation of elevated inflammatory markers or increased oxygen requirement. Treatment was individualized given the lack of established guidelines for aortic thrombus, including anticoagulation, systemic and catheter directed thrombolysis, and surgical thrombectomy. Overall mortality was found to be 30% in our study. Conclusions: Although rare, aortic thrombus has high morbidity and mortality, and can present without any symptoms or underlying aortic disease. Aortic thrombosis is rare, but if not considered early in the course of COVID-19 infection, the data suggest that the diagnosis will probably not be made until potentially serious complications arise.