[Acquired hemophilia A that developed after BNT162b2 mRNA COVID-19 vaccination and worsened following re-vaccination].

An 86-year-old Japanese male patient visited a nearby hospital with painful swelling in his left upper and lower limbs 35 days after the second dose of the BNT162b2 mRNA coronavirus disease-2019 (COVID-19) vaccine. He was referred to our hematological department due to a prolonged activated partial thromboplastin time and was urgently admitted. He was diagnosed with acquired hemophilia A (AHA) based on factor VIII (FVIII) activity of 1.7%, FVIII inhibitor of 152.3 BU/ml, and FVIII-binding antibodies detected by enzyme-linked immunosorbent assay. Immunosuppressive therapy with prednisolone (PSL) at 0.5 mg/kg/day was started owing to the risk of infection due to old age and poor activities of daily living. Hemostasis treatment with bypass hemostatic preparations (rFVIIa preparation, FVIIa/FX) was administered for each bleeding event, such as intramuscular and knee joint bleeding, resulting in good hemostatic effects. Coagulative complete remission was achieved on day 69 with PSL treatment; however, FVIII activity decreased with PSL tapering. AHA relapse with rectus abdominis muscle hematoma was observed after the third vaccination. This is the first Japanese report of AHA after COVID-19 vaccination and the world's first case, in which the presence of anti-FVIII-binding antibodies were observed.

[Refractory thrombotic thrombocytopenic purpura complicated with multiple cerebral infarction].

Neuropsychiatric symptoms comprise one of the five classic symptoms of autoimmune thrombotic thrombocytopenic purpura (aTTP). Although aTTP is typically transient, it is sometimes complicated by cerebral infarction with residual disability. This report presents the case of an 87-year-old man previously admitted to a different hospital with fever and transient consciousness loss. After receiving platelet transfusion with diagnosis of Evans syndrome, he was transferred to our hospital with worsening consciousness disturbance. He was subsequently diagnosed with aTTP with a PLASMIC score of 6 points, ADAMTS13 activity of less than 0.5%, and its inhibitor of 7.4 BU/ml. Platelet count and consciousness were rapidly improved with plasmapheresis and steroids, but motor aphasia emerged. MRI showed multiple cerebral infarctions, including a large infarction in the left frontal lobe. Thus, unfractionated heparin was administered. When his platelet count dropped once again on the 20th day, rituximab was added. The treatment eventually proved to be successful, and his aTTP remained in remission one year after the onset. Treatment for cerebral infarctions was switched to DOAC, and rehabilitation was continued. However, his ADL has not yet recovered. Advances in aTTP treatment have cured many similar cases. Thus, rituximab is now considered a treatment option for refractory cases. However, ischemic organ damage in acute phase and sequelae are observed. Therefore, early diagnosis and novel therapy are required.

Guillain-Barré syndrome after SARS-CoV-2 infection.

We herein report a case of Guillain-Barré syndrome (GBS) after SARS-CoV-2 infection. The patient was a close contact with a SARS-CoV-2 patient. Initially, she did not have any symptoms and quarantined at a hotel. Dysgeusia and olfactory abnormality appeared at day 6 after testing positive for infection and disappeared by day 9. Subsequently, the patient developed numbness of the arms and legs, difficulty walking, and dyspnea and was referred to our hospital. Her clinical examination showed generalized weakness and hyporeflexia. A cerebrospinal fluid analysis showed albuminocytological dissociation. Her nerve conduction studies were consistent with demyelinating polyneuropathy. Intravenous immunoglobulin was administered based on a diagnosis of GBS.