Case Report
Acquired Factor XI Inhibitor Presenting as Spontaneous Bilateral Subdural Hematoma in an Elderly Patient
| Variable | 18 months before | Admission | Reference range |
| Hematocrit, % | 38.1 | 28.2 | 39.0–50.0 | Hemoglobin, g/dL | 12.4 | 9.2 | 13.2–17.0 | platelet count, ×109/L | 435 | 200 | 150–400 | PT, % | 93 | 75 | 70–110 | INR | 1.06 | 1.18 | | aPTT, sec | 25 | 51 | 22–34 | Fibrinogen, mg/dL | — | 710 | 200–420 | FVIII, % | — | 263 | 70–150 | FIX, % | — | 95 | 70–150 | FXI, % | — | 31 | 70–150 | Lupus anticoagulant | — | absent | absent | Total protein, g/dL | 5.1 | 6.3 | 6.1–8.1 | Serum protein electrophoresis | | | | Albumin, % | — | 36.6 | 55.8–66.1 | alpha1, % | — | 6.7 | 2.9–4.9 | alpha2, % | — | 11.5 | 7.1–14.8 | beta1, % | — |
6.6 | 4.7–7.2 | beta2, % | — | 7.2 | 3.2–6.5 | gamma, % | — | 31.4 | 11.1–18.8 |
|
|