The presentation and diagnostic utility of xanthochromia in current practice

Background

Cerebrospinal fluid (CSF) xanthochromia, when diagnosed with spectrophotometry, is highly sensitive and specific for subarachnoid hemorrhage. However, most laboratories in North America currently rely on visual inspection rather than spectrophotometry for assessment of xanthochromia, making it less specific for the presence of hemoglobin degradation products and inclusive of other etiologies for yellow discoloration of the cerebrospinal fluid.

Case report

We present a series of cases from our inner-city community hospital to demonstrate how CSF xanthochromia is not specific to subarachnoid hemorrhage. There are three patients who presented with yellow-colored CSF but were ultimately diagnosed with meningitis or leptomeningeal carcinomatosis and one patient who presented with pink-colored CSF and was diagnosed with a true aneurysmal bleed.

Why should an emergency physician be aware of this

Subarachnoid hemorrhage is a life-threatening emergency that is always on an emergency physician's list of differential diagnoses in a patient with acute headache. Our series of cases suggest the importance of correctly interpreting lumbar puncture findings and relying on spectrophotometry rather than visual inspection of the CSF to rule xanthochromia—and, consequently, subarachnoid hemorrhage—in or out.