[Epub ahead of print]

[Epub ahead of print]. as thrombotic thrombocytopenic syndrome (TTS) following ChAdOx1 nCoV\19 vaccination (AstraZeneca), a recombinant replication\deficient chimpanzee adenovirus vector. 1 The syndrome, now recognized as vaccine\induced thrombotic thrombocytopenia (VITT), results in pathologic anti\platelet factor 4 (PF4) antibodies leading to thrombocytopenia and thrombosis in the absence of heparin exposure, a mechanism much like autoimmune heparin\induced thrombocytopenia (HIT). 2 , 3 On April 13th, 2021, six cases of VITT were reported in Cetirizine Dihydrochloride the United States following vaccination by the Ad26.COV2.S vaccine, all of whom were women who developed cerebral venous sinus thrombosis (CVST). 4 This led to an 11\day pause in the administration of the vaccine, during which a thorough investigation led to its resumption by the Centers for Disease Control (CDC) and FDA, but revised to include a warning about this rare side effect. By April 27th, 2021, the number of VITT cases following Ad26.COV2.S vaccination reported in the US had risen to 15, all of whom were women of ages 20 to 50?years, and included 12 incidences of CVST. 5 , 6 To date, the only statement of suspected VITT in a male Ad26.COV2.S vaccine recipient in the medical literature comes from the initial Johnson & Johnson phase 3 trials. One of the male trial participants who developed CVST, thrombocytopenia, and positive anti\PF4 antibodies is usually suspected to have had VITT, but additional details have not been provided. 7 We hereby statement the case of a man with confirmed VITT following Ad26.COV2.S vaccination, resulting in acute deep venous thrombosis (DVT) and bilateral pulmonary emboli (PE), and a post\discharge course complicated by refractory thrombocytopenia. A 48\12 months\aged male with a history of asthma offered to a community emergency room in Salt Lake County, Utah, with bilateral lower extremity pain on April 26th, 2021, 19?days after receiving the Ad26.COV2.S vaccine on April 7th. The pain in the beginning started in his toes a week prior (11?days post\vaccination), and then progressed to his thighs bilaterally. He was healthy and exercised regularly, was not on any medications, and had by no means smoked. He Cetirizine Dihydrochloride flew out of town and back on March 30th and April 4th, respectively, with the longest continuous flight lasting around 4?h. He also flew again on April 22nd and April 25th on one\hour long flights. His last known platelet count in 2019 was 177??109/L. In the emergency room, he had normal vital indicators and oxygen saturation, and was found to have a platelet count of 74??109/L, fibrinogen of 254?mg/dL, D\dimer of 15?109?ng/mL FEU, and an activated partial thromboplastin time (aPTT) of 31.8?s. Detailed laboratory work\up and reference ranges are outlined in Table?1. Venous duplex ultrasound of the lower extremities revealed non\occlusive DVT in the bilateral popliteal veins extending to the gastrocnemius veins, an occlusive DVT of the left posterior tibial vein, as well as occlusive superficial venous thrombosis in the bilateral saphenous veins. He was discharged on rivaroxaban 15?mg twice\daily with two\day follow\up with his main care physician. He had no known exposure to heparin before the onset of symptoms and no exposure during his emergency room visit. TABLE 1 Selected laboratory values thead valign=”bottom” Cetirizine Dihydrochloride th align=”left” valign=”bottom” rowspan=”1″ colspan=”1″ Test Rabbit Polyclonal to NAB2 name (models as relevant) /th th align=”left” valign=”bottom” rowspan=”1″ colspan=”1″ Result /th th align=”left” valign=”bottom” rowspan=”1″ colspan=”1″ Reference interval /th /thead CBC (initial presentation)WBC (K/L)5.83.2C10.6RBC (M/ L)5.073.98C5.98Hemoglobin (g/dL)15.012.5C18.0Hematocrit (%)42.236.9C52.1MCV (fL)83.280.6C97.6MCHC (g/dL)35.533.4C35.3Platelets (K/L)74140C440Hemostasis Assessments (initial presentation)D\dimer (ng/mL FEU)15?1090C499PT (s)12.710C13aPTT (s)31.825.1C36.5Fibrinogen (mg/dL)254150C430Thrombophilia Assessments a Prothrombin G20210A mutationNot detectedNot detectedFactor V Leiden mutationNot detectedNot detectedLupus anticoagulant interpretationNot detectedNot detectedAnticardiolipin IgG.