Table 1. Characteristics of the Patients.*.
| Characteristic | Patient 1 | Patient 2 | Patient 3 | Patient 4 | Patient 5 |
|---|---|---|---|---|---|
| Age — yr | 37 | 42 | 32 | 39 | 54 |
| Sex | Female | Female | Male | Female | Female |
| Preexisting conditions | Pollen allergy | Pollen allergy | Asthma | None | Hypertension |
| Medication on admission | Contraceptive pill | Contraceptive vaginal ring | None | None | Hormone-replacement therapy, antihypertensive agents |
| Time from vaccination to admission — days | 8 | 10 | 7 | 10 | 7 |
| Symptoms | Fever, headaches, visual disturbances | Headaches, drowsiness | Back pain | Headaches, abdominal pain | Headaches, hemiparesis |
| Location of thrombosis | Cortical veins, left transverse sinus, and sigmoid left sinus | Cortical veins, left transverse sinus, and left sigmoid sinus | Portal vein, left hepatic vein, splenic vein, azygos vein, hemiazygos vein, and several basivertebral veins | Inferior sagittal sinus, vein of Galen, straight sinus, right transverse sinus, and right sigmoid sinus | Cortical veins, superior sagittal sinus, both transverse sinuses, and left sigmoid sinus |
| Platelet count nadir — per mm3 | 22,000 | 14,000 | 10,000 | 70,000 | 19,000 |
| d-dimer peak — mg/liter | >35 | >35 | >35 | 13 | >35 |
| INR peak | 1.2 | 1.0 | 1.1 | 1.3 | 1.1 |
| aPTT peak — sec | 25 | 31 | 25 | 25 | 29 |
| Fibrinogen nadir — g/liter† | 2.1 | 0.8 | 2.3 | 1.2 | 1.2 |
| SARS-CoV-2 antibody test results | |||||
| Nucleocapsid protein | Negative | Negative | Negative | Negative | Negative |
| Spike protein | Positive | Positive | Positive | Positive | Positive |
| Anticoagulation treatment | Initial low dose of LMWH | Reduced dose of LMWH | Reduced dose of LMWH | Reduced dose of LMWH | Heparin (5000 IU) |
| No. of platelet units transfused | 7 | 19 | 2 | 0 | 2 |
| Other treatment | None | Methylprednisolone (1 mg/kg), IVIG (1 g/kg) | Prednisolone (1 mg/kg), IVIG (1 g/kg) | Prednisolone (1 mg/kg), IVIG (1 g/kg) | Methylprednisolone (1 mg/kg), IVIG (1 g/kg) |
| Outcome | Fatal | Fatal | Full recovery | Full recovery | Fatal |
*
The abbreviation aPTT denotes activated partial thromboplastin time, INR international normalized ratio, IVIG intravenous immune globulin, LMWH low-molecular-weight heparin, and SARS-CoV-2 severe acute respiratory syndrome coronavirus 2.
†
The reference range used for fibrinogen at Oslo University Hospital is 1.9 to 4.0 g per liter.