CSF Xanthochromia
Biochemistry Overview / Directory
Purpose of the test
This test is performed to identify patients who have had a subarachnoid haemorrhage (SAH) but in whom the CT scan is negative. The formation of bilirubin after haemorrhage is a time dependent process and bilirubin may not be detected soon after the onset of symptoms e.g. severe headache.
Please indicate on the request form:
- Clinical indication for request
- Result of CT scan was discussed with
- Time of onset of symptoms/event
- Time of LP
- If the differential diagnosis includes meningitis
- Lab results for CSF total protein and serum bilirubin with normal reference ranges (FOR EXTERNAL HOSPITALS)
7. Contact details for referring doctor
Sample Requirements
It is recommended that CSF is not sampled until at least 12hrs after a suspected event.
After collection of 3 bottles for CSF examination, a further 1ml CSF should be collected into the 4th universal tube for xanthochromia.
Upon receipt the specimen for spectrophotometry should be centrifuged at >2000rpm for 5 minutes as soon as possible or within 1 hr of collection.
It is recommended that a blood specimen is taken at the same time as the CSF specimen for serum bilirubin, total protein and glucose measurements.
Storage and Transport
This CSF specimen should be protected from light either in foil wrap or brown envelope and brought to the Lab by hand as pneumatic tube delivery could fragment red cells.
The supernatant should be stored in the dark at 4 degrees C until analysis (or sent directly to the Central Specimen Reception - Ground Floor, Bessemer Wing - at KCH by courier for External Hospitals).
Turnaround Time
Allow 2 working days.
Currently this service is available 09:00 to 16:00 weekdays only. Outside these times, the sample will be analysed on the next working day.
Positive results will be telephoned to the doctor requesting the test.
Price
Price available on application - please contact adrian.turner@kch.nhs.uk. Discounts could be available for significant workloads.
Contacts
Dr. Royce Vincent (Specialist Registrar)
Tel: 020 - 3299 4924
e-mail: royce.vincent@nhs.net
Dr Joanne Marsden (Principal Biochemist)
Tel: 020 - 3299 3856
e.mail: joannemarsden1@nhs.net
