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Blood Sciences Test


Sodium citrate tube

Minimum Sample Volume

1.8 mL adult or 1.3 mL paediatric tube. An additional coag tube is not required if other coag requested.

Special Instructions

Ideally specimens should be received in the laboratory on the day of venepuncture but may be stored at room temperature overnight if a delay is unavoidable.

Repeat samples taken at intervals of < 3 days are normally rejected

Factors affecting results

Haemolysed, clotted and aged samples cannot be tested (see coagulation screen test)

May be raised in some pathological conditions, during pregnancy and post-operatively

Reference Range

Adult less than 50 years old <230 ng/ml

For adults >50 years old an age related cut off is used (age x5)

The result is accompanied by an interpretive comment

Source of range calculation:

Int J Lab Hematol. 2014 Oct;36(5):541-7. doi: 10.1111/ijlh.12184. Epub 2014 Jan 16.

D-dimer use for deep venous thrombosis exclusion in elderly patients: a comparative analysis of three different approaches to establish cut-off values for an assay with results expressed in D-dimer units.

Cini MLegnani CFrascaro MSartori MCosmi BPalareti G.

Test Usage

Used in conjunction with Wells scoring, a negative  D Dimer may be used to exclude a Thrombotic event. A positive result may be due to other causes.

Turnaround time

1 hr – STAT samples

4 hr – routine samples


In house

Clinical Advice

Clinical advice is available from the Haematology Medical team (contact RD&E switchboard on 01392 411611)

Minimum Repeat Interval

4 days

Specimen Labelling Procedure
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