CSF Chemistry


Cerebrospinal fluid (CSF) analysis is a group of laboratory tests that measure chemicals in the fluid that surrounds and protects the brain and spinal cord. The tests may look for proteins, sugar (glucose), and other substances.

Alternative Names

Cerebrospinal fluid analysis

How the Test is Performed

A sample of CSF is needed. A lumbar puncture, also called a spinal tap, is the most common way to collect this sample. Less common ways to take a fluid sample include:

After the sample is taken, it is sent to the laboratory for evaluation.

How to Prepare for the Test

Your health care provider will tell you how to prepare for lumbar puncture.

Why the Test is Performed

Analysis of CSF can help detect certain conditions and diseases. All of the following can be, but are not always, measured in a sample of CSF:

Normal Results

Normal results include:

  • Antibodies and DNA of common viruses: None
  • Bacteria: No bacteria grows in a lab culture
  • Cancerous cells: No cancerous cells present
  • Cell count: less than 5 white blood cells (all mononuclear) and 0 red blood cells
  • Chloride: 110 to 125 mEq/L (110 to 125 mmol/L)
  • Fungus: None
  • Glucose: 50 to 80 mg/dL or 2.77 to 4.44 mmol/L (or greater than two-thirds of blood sugar level)
  • Glutamine: 6 to 15 mg/dL (410.5 to 1,026 micromol/L)
  • Lactate dehydrogenase: less than 2.0 to 7.2 U/mL (0.3 to 0.12 microkat/L)
  • Oligoclonal bands: 0 or 1 bands that are not present in a matched serum sample
  • Protein: 15 to 60 mg/dL (0.15 to 0.6 g/L)

Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results.

The examples above show the common measurements for results for these tests. Some laboratories use different measurements or may test different specimens.

Note: mg/dL = milligrams per deciliter and mmol/L =  millimoles per liter

What Abnormal Results Mean

An abnormal CSF analysis result may be due to many different causes, including:

  • Cancer
  • Encephalitis (such as West Nile and Eastern Equine)
  • Hepatic encephalopathy
  • Infection
  • Inflammation
  • Reye syndrome
  • Meningitis due to bacteria, fungus, tuberculosis, or a virus
  • Multiple sclerosis (MS)
  • Alzheimer disease
  • Amyotrophic lateral sclerosis (ALS)


Griggs RC, Jozefowicz RF, Aminoff MJ. Approach to the patient with neurologic disease. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 396.

Martorana A, Sancesario GM, Esposito Z, et al. Plasmin system of Alzheimer's disease: CSF Analysis. J Neural Transm. 2012:119:763-769. PMID: 22415062. www.ncbi.nlm.nih.gov/pubmed/22415062.

Rosenberg GA. Brain edema and disorders of cerebrospinal fluid circulation. In: Daroff RB, Fenichel GM, Jankovic J, Mazziotta JC, eds. Bradley's Neurology in Clinical Practice. 6th ed. Philadelphia, PA: Elsevier Saunders; 2012:chap 59.

Review Date: 6/1/2015

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. Copyright ©2017 A.D.A.M., Inc., as modified by University of California San Francisco. Any duplication or distribution of the information contained herein is strictly prohibited.

Information developed by A.D.A.M., Inc. regarding tests and test results may not directly correspond with information provided by UCSF Medical Center. Please discuss with your doctor any questions or concerns you may have.