View source for Template:Lumbar Puncture Diagnosis

{| class="wikitable"
| align="center" style="background:#f0f0f0;"|'''Measure'''
| align="center" style="background:#f0f0f0;"|'''Normal'''
| align="center" style="background:#f0f0f0;"|'''[[Bacterial meningitis|Bacterial]]'''
| align="center" style="background:#f0f0f0;"|'''[[Viral meningitis|Aseptic (Viral)]]'''
| align="center" style="background:#f0f0f0;"|'''[[Fungal meningitis|Fungal]]'''
| align="center" style="background:#f0f0f0;"|'''[[Tuberculosis]]'''
| align="center" style="background:#f0f0f0;"|'''[[Subarachnoid hemorrhage]]'''
| align="center" style="background:#f0f0f0;"|'''Neoplastic'''
|-
| '''Appearance'''||Clear||Clear, cloudy, or purulent||Clear||Clear or opaque||Clear or opaque||Xanthochromia, bloody, or clear||Clear or opaque
|-
| '''Opening Pressure (cm H2O)'''||10-20||>25||Normal or elevated||>25||>25||>25||Normal or elevated
|-
| '''WBC Count^ (cells/µL)'''||0-5^||>100^||5-1000||<500|| 50-500||0-5 (see correction section)||<500
|-
|  '''% PMNs'''||||>80-90%||1-50%^^||1-50%||Early PMN then lymph||||1-50%
|-
| '''Glucose'''||>60% of serum glucose|| Low||Normal||Low||Low||Normal||Normal
|-
| '''Protein^^^ (mg/dL)'''||< 45||Elevated||Elevated||Elevated||Elevated||Elevated||>200
|-
| '''Gram Stain'''||Neg||Pos||Neg||India ink||Tb stain||Blood||
|}

*^Normal or lower WBC results may be found in immunocompromised, early, or partially treated (e.g. with oral antibiotics) bacterial menintigis, and those with tuberculosis meningitis
*^^Lymph predominance may be found in patients with early bacterial meningitis or those that have been partially treated (e.g. with oral antibiotics)
*^^^For unexplained elevations of protein, consider [[encephalitis]], [[MS]], [[Guillian Barre]]

'''Corrections'''
*WBC correction (for bloody tap)
**Simplified version (if peripheral WBC and RBC counts are within normal limits):
***Subtract 1 WBC for every 750 RBC in CSF
**Complex version (WBC and/or RBC not within normal limits):
***"WBCs added" = WBC(blood) x [RBC(CSF) / RBC(blood)]
***WBC counted/resulted - "WBCs added" = actual WBC
*Protein correction (for bloody tap)
**For each 1000 RBC decrease protein value by 1mg/dl