VITT following Ad26.COV2.S vaccination presenting without radiographically demonstrable thrombosis

Abstract

We report a case of vaccine-induced immune thrombotic thrombocytopenia (VITT) in a young man diagnosed 13 days after Ad26.COV2.S COVID-19 (Johnson & Johnson/Janssen) vaccination. He presented to us with 5 days of progressive left leg pain, thrombocytopenia, hypofibrinogenemia, and markedly elevated d-dimers, but without radiographically demonstrable thrombosis. Despite negative imaging, we initiated treatment of presumptive VITT given the striking clinical picture that included the timing of his recent adenovirus-based COVID-19 vaccine, leg symptoms, marked thrombocytopenia, and consumptive coagulopathy. He received intravenous immune globulin, prednisone, and argatroban and was discharged 7 days later much improved. His positive platelet factor 4 enzyme-linked immunosorbent assay antibody test returned after treatment was initiated. To our knowledge, this is the first reported case of VITT following Ad26.COV2.S vaccination presenting without radiographically demonstrable thrombosis. Our patient highlights the importance of knowing vaccine status and initiating treatment as soon as possible in the right clinical setting, even in the absence of radiographic evidence of thrombus. Early VITT recognition and treatment provide an opportunity to prevent serious thrombotic complications.

Graphical abstract

Figure 1.

Platelet count, fibrinogen, D-dimer, and treatment over time. The X-axis indicates the days following Ad26.COV2.S vaccination. The left Y-axis indicates platelet count and fibrinogen concentration; the right Y-axis indicates D-dimer concentration. Normal range for platelet count (140-450 ×10⁹/L), fibrinogen (202-430 mg/dL), d-dimer (<500 ng/mL). *>14 000 is the maximum d-dimer value reported by our laboratory. Hospitalization, the gray-shaded column, indicates the time from presentation to our emergency department until discharge from the hospital. IVIG (1 g/kg) was administered to increase platelet count to allow for safe initiation of anticoagulation. Cryoprecipitate (first dose 10 units; second dose 5 units) was given to improve fibrinogen levels to allow for safe initiation of anticoagulation. Prednisone 1 mg/kg per day with taper. Therapeutic argatroban was dosed for target activated partial thromboplastin time of 60 to 80 seconds. Apixaban 10 mg twice daily ×7 days followed by 5 mg twice daily.