Cerebrospinal fluid (CSF) culture

What is CSF Culture?

CSF Culture, also known as cerebrospinal fluid culture, is a laboratory test used to detect the presence of bacteria, viruses, and other microorganisms in the cerebrospinal fluid (CSF). CSF is the clear fluid that surrounds the brain and spinal cord, and is collected by a lumbar puncture test, also known as a spinal tap.

Why is a CSF Culture Done?

A CSF culture is used to diagnose the cause of meningitis, an inflammation of the lining of the brain and spinal cord. Meningitis is caused by bacterial, viral, or fungal infections. In some cases, a CSF culture is also used to track the effectiveness of an antimicrobial treatment.

Preparation for the CSF Culture

If a patient needs to have a CSF culture done, they may not need any specific preparation for the test. However, general guidelines exist, including:

  • Tell your doctor about any medications you are taking, such as aspirin or blood thinners, as these may interfere with the culture.
  • Do not eat or drink anything for six hours prior to the test.
  • Do not urinate for one hour prior to the test, as this may contaminate the sample.

Procedure for the CSF Culture

The procedure for the CSF culture is as follows:

  1. The patient lies down on their side with their legs bent, and their head resting on one hand.
  2. An anesthetic will be injected to numb the area.
  3. A small needle is inserted through the skin and between two vertebrae in the lower back into the spinal canal.
  4. A sample of CSF is drawn out with a syringe.
  5. The sample is sent to the laboratory for testing.

Types of CSF Culture

There are two main types of CSF culture. These are:

  • Direct Microscopy: This is a rapid test that examines a sample of CSF under a microscope to look for organisms such as bacteria, parasites, and yeast.
  • Bacterial Culture: Bacterial cultures are used to isolate and identify the specific type of bacteria that is causing the infection.

Risks of CSF Culture

The risks associated with a CSF culture are fairly minimal. These include:

  • Headache
  • Dizziness
  • Nausea
  • Back pain at the puncture site
  • Infection at the puncture site

When Should a CSF Culture Be Done?

A CSF culture is done when a doctor suspects that a patient has meningitis. It is also used to track the effectiveness of an antimicrobial treatment. It is important to note that a CSF culture is not used to diagnose other neurological disorders such as stroke, Alzheimer's disease, or brain tumors.