CSF analysis with SAH has xanthochromia


CSF RBC over 5000 can be considered traumatic LP. However, one must differentiate this with SAH, which could have xanthochromia and discoloration from hemoglobin greakdown.

source

A RBC count exceeding 6,000/mm3 may indicate traumatic LP, but other important causes, mainly subarachnoid hemorrhage (SAH), should be ruled out. WBC elevation in traumatic LP is commonly explained by the blood leak if approximately one WBC is present per 750-1000 RBCs. The protein level is elevated in the presence of traumatic LP, and the glucose level is typically high.

Important findings that help to differentiate traumatic LP from SAH are xanthochromia and discoloration of centrifuged CSF due to hemoglobin breakdown. These are characteristic for SAH, and appear 2 to 4 hours after RBCs enter the subarachnoid space. These are present in more than 90% of patients within 12 hours of SAH.

XanthochromiaAbsent
RBCs75,000/mm3
WBCs100/mm3
Protein50 mg/dL
Glucose90 mg/dL