Laboratory Medicine
Test Directory / Coagulation factor XI assay
Coagulation factor XI assay
Citrated Plasma
| Test | Coagulation factor XI assay |
|---|---|
| Common Abbreviations | FXI |
| Profile | Coagulation Screen added on the same sample |
| Clinical Indication | To determine if the coagulation factor XI is low or absent. Associated with reduced clot formation and bleeding. Coagulation factor levels may also be measured to monitor the level during therapy. Contact Consultant Haematologist for advice. |
| Specimen Type | Blood |
| Sample Type | Citrated Plasma |
| Minimum Volume | 2 x 3 mL (adult) 2 x 1 mL (paed) (citrated plasma must be filled to bottle line) |
| Special Precautions | Must write type of replacement factor product if relevant. Must state if patient is on anticoagulants (DOAC, Warfarin, Heparin); known coagulation disorders; clincal symptoms (bleeding, bruising). |
| Stability | 4-6 hours |
| Turnaround Time | 4 hours (urgent) if requested via the haematology consultants. 3 weeks (routine) |
| Laboratory | York Hospital |
| Reference Interval | Reference range printed on final report. |
| Limitations | Haemolysis, gross lipaemia, high haematocrit may interfere with measurement. Over or under filled samples cannot be used due to ratio between blood and citrate |
| Additional Information |
