Cerebrospinal fluid (CSF) analysis - Meningitis. CSF protein, glucose, gram stain, cultures, wbc, leukocytes.

Common Laboratory (LAB) Values - [CSF Analysis]

Cerebrospinal fluid (CSF) analysis - Meningitis

Normal values (CSF):

CSF opening pressure: 50–180 mmHg
Glucose: 40–85 mg/dL.
Protein (total): 15–45 mg/dL.
Lactate dehyrogenase: 1/10 of serum level.
Lactate: less than 35 mg/dL.
Leukocytes (WBC): 0–5/µL (adults / children); up to 30/µL (newborns).
Gram stain: negative.
Culture: sterile.
Specific gravity: 1.006–1.009.
Syphilis serology: negative.
Gross appearance: Normal CSF is clear and colorless.
Differential: 60–70% lymphocytes; up to 30% monocytes
and macrophages; other cells 2% or less.

Bacterial Meningitis

Glucose (mg/dL):	Normal to marked decrease. <40 mg/dL.
Protein (mg/dL)	(Marked increase) > 250 mg/dL.
WBCs (cells/µL)	>500 (usually > 1000). Early: May be < 100.
Cell differential:	Predominance of Neutrophils (PMNs)
Culture:	Positive
Opening Pressure	Elevated

Fungal Meningitis

Glucose (mg/dL):	<40 mg/dL (Low)
Protein (mg/dL)	(moderate to marked increase) 25 -500 mg/dL
WBCs (cells/µL)	Variable (10 -1000 cells/µL) <500cells/µL.
Cell differential:	Predominance of Lymphocytes
Culture:	Positive (fungal)
Opening Pressure	Variable

Tubercular Meningitis

Glucose (mg/dL):	<40 mg/dL (Low)
Protein (mg/dL)	(moderate to marked increase) 50 -500 mg/dL
WBCs (cells/µL)	Variable (10 -1000 cells/µL) <500cells/µL.
Cell differential:	Predominance of Lymphocytes
Culture:	Positive for AFB
Opening Pressure	Variable

Viral Meningitis

Glucose (mg/dL):	Normal (> 40 mg/dL.)
Protein (mg/dL)	<100 mg/dL (moderate increase)
WBCs (cells/µL)	< 100 cells/µL.
Cell differential:	Early: neutrophils. Late: lymphocytes.
Culture:	Negative
Opening Pressure	Usually normal

Important Notes

>Unless noted, all values are for adults.

Common Laboratory (LAB) Values - [CSF Analysis]