Cerebrospinal Fluid

Authors: Flaherty, Alice W.; Rost, Natalia S.

Title: Massachusetts General Hospital Handbook of Neurology, The, 2nd Edition

Copyright 2007 Lippincott Williams & Wilkins

> Table of Contents > Adult Neurology > Cerebrospinal Fluid

Cerebrospinal Fluid

A. Lumbar puncture technique

see p. 224.

B. CSF findings by dz

C. Dz by CSF profile

• 1. Many PMNs, low sugar, high protein:

  • a. Infectious: Bacterial meningitis, early viral or TB meningitis, parameningeal infections, septic emboli.

  • b. Noninfectious: Chemical meningitis, Beh et's dz, Mollaret's recurrent meningitis.

• 2. Many lymphocytes, low sugar, high protein: Tb, fungal, or partially treated/resolving bacterial meningitis, viral meningitis, carcinomatous meningitis, meningeal sarcoidosis.

• 3. Many lymphocytes, normal sugar, high protein: Viral meningitis or encephalitis, partially treated/resolving bacterial meningitis, parameningeal infections, early fungal or TB meningitis, parasitic infections, postinfectious encephalomyelitis, active demyelinating dz.

D. Skull CSF leak

May be a sign of CSF obstruction.

• 1. H&P: Skull trauma, transsphenoidal surgery, clear watery nasal or ear drainage when leaning forward or sneezing. Have pt. lean forward for several min to elicit nasal discharge.

• 2. Tests: To tell CSF from nasal secretions.

  • a. Handkerchief test: When CSF dries on tissue (e.g., Kleenex), it is still flexible. Snot is stiff.

  • b. Vodka test: Nasal mucin precipitates in alcohol; CSF does not.

  • c. Dip stick: Glucose is positive in CSF, not in snot.

  • d. Labs: CSF glucose >20, chloride > serum Cl. Tau/transferrin.

• 3. Rx: Elevate the HOB. If there is a transsphenoidal incision, reinforce it with more sutures or several coats of colloidon. Lumbar drain; prophylactic nafcillin 3 days. Hang drain bag as low as possible without causing headache (usually level of heart).

E. LP headache/spinal CSF leak

See Headache, p. 52.