The following results were found in a 28-year-old woman as part of a work up for infertility. She has never had a history of bleeding or bruising nor does she have a family history for bleeding.
| Test | Patient | Reference Range |
| PT | 11s | 11-14s |
| APTT | 44s | 23-35s |
| Fibrinogen | 2.9g/L | 1.5-4.0g/L |
| Thrombin Time | 12s | 10-13s |
- What are the causes of an elevated PTT in a non-bleeding patient?
- Describe the additional tests that would be required to make a diagnosis in this case.
- What is a lupus anti-coagulant and how does it alter the PTT?
