CSF Xanthochromia
Code:
XANTH
Sample Type:
CSF (please phone biochemistry to obtain collection kit with sample tubes and instructions).
Minimum volume: 1 mL
CSF sample collection information can be found here
Paired blood samples are also required:
Serum sample (5 mL Gold Topped Tube) for LIVER panel
Plasma sample (5 mL Fluoride-Oxalate Grey Topped Tube) for glucose
Ref Ranges/Units:
N/A – reported as positive, negative, inconclusive or equivocal.
Any positive result will be urgently phoned to the requesting clinician.
Turnaround:
Available on an urgent basis Monday – Sunday 8am – 8pm.
Special Precautions/Comments:
Patient must have a negative CT.
Sample must be taken >12 hours post suspected event.
Use the last CSF fraction for xanthochromia analysis (least blood-stained).
Protect sample from light.
Do not send samples via pneumatic air tube.
Please note: CSF infection can reduce the PPV of the test and may lead to inconclusive, equivocal, or falsely positive results.
Additional Information:
CSF xanthochromia is used to investigate suspected subarachnoid haemorrhage (SAH) in patients with a negative CT scan. Although CT scanning is usually sufficient to diagnose SAH in patients presenting within 12 hours, sensitivity of CT for diagnosis of SAH decreases after this time.
After a haemorrhage into the CSF, oxyhaemoglobin and bilirubin are formed in vivo following red blood cell lysis. These can therefore be measured in CSF to determine if SAH has occurred.
South of Tyne & Wear Pathology Centre
