CSF/ Spinal Taps Flashcards
Red blood cells in the tap
With no xanthochromia: traumatic tap
With xanthochromia: subarachnoid hemorrhage; hemorrhagic encephalitis.
White blood cells in the tap
Polymorphs: bacterial or early viral infection
Lymphocytes: Infection (vieal, fungal, mycobacterial; demylination (MS, ADEM); CNS lymphoma
Elevated protein
Infetion; demyelination; tumor (e.g., meningioma); age.
Low glucose
Bacterial Infection; mycobacterial infection
Oligoclonal bands
Demyelination (MS); CNS infections (e.g., Lyme Disease); noninfectious inflammatory processes (e.g., SLE)
Positive EBV PCR
Highly suggestive of CNS lymphoma in patients with AIDs or other immunosuppressed states.
Common findings for Bacterial Meningitis
Polymorphs (500-5,000), high protein (100-500), low glucose (<40), culture and gram stain may be positive
Treatment: Abx
Common findings for Viral Meningitis/Encephalitis
Lymphocytes (or polys in early infection) (100-2,000), high protein (or normal/mildly elevated in acute viral meningitis), normal glucose, PCR may be positive. Treatment is supportive except treat herpesvirus with acyclovir.
Common findings for Tuberculous meningitis
Lymphocytes, high protein, VERY low glucose, positive for acid-fast bacilli
Guillain-Barre Syndrome
No WBCs, high protein (degree depends on interval from symptom onset), normal glucose.
MS
Few lymphocytes, slightly high protein, normal glucose, OCBs usually present.
ADEM
Few lymphocytes or polys, protein is usually high, glucose normal, OCBs usually absent.
Subarachnoid Hemorrhage
Lymphocytes and many RBCs, protein may be high, glucose is normal, xanthochromia.
Common findings for chronic meningitis (bacterial and fungal)
Elevated WBCs (100-700), predominantly lymphocytes; markedly elevated protein (>100), very low glucose, positive microscopic analysis, treat with antifungals/antibiotics
