HSV DNA (CSF)

Does this test have other names?

Herpes simplex 1 infection, herpes simplex 2 infection

What is this test?

This test looks for the herpes simplex virus (HSV) DNA in your cerebrospinal fluid (CSF). It  diagnoses herpes simplex infection in the nervous system. The test is especially useful to find out whether HSV is causing encephalitis, an infection of the brain, or meningitis, an infection of the fluid surrounding the spinal cord and brain.

There are two types of HSV: HSV-1 and HSV-2. HSV-1 generally causes oral herpes, or cold sores and blisters. HSV-2 causes genital herpes. Both types of herpes can cause outbreaks on any part of your body. Other symptoms might include headaches, fever, and general discomfort.  

HSV is the most common type of genital ulcer illness. First-time infections are usually more severe than later outbreaks.

You can get HSV from having unprotected sex with an infected partner. If your immunity is weakened, you may be more likely to get HSV. Menstruation, fatigue, and illness can trigger an HSV outbreak.

In rare cases, HSV causes more severe infections. These include encephalitis and meningitis.

HSV can be passed from a pregnant woman to her fetus. At least half of newborns with a herpes infection will die. Those who live often have acute illnesses that affect the brain and can also damage the eyes and nerves.

You may have a miscarriage if your fetus gets herpes during early pregnancy. You should not give birth to a baby through your birth canal if it is actively infected with herpes. C-sections are recommended as an alternative. 

Why do I need this test?

You may be given this test if your doctor suspects that you have meningitis or encephalitis caused by HSV.

Symptoms of HSV infection of the nervous system include:

• Fever

• General discomfort, such as body aches

• Headache

• For women, small bubbles on the cervix, vagina, and inner thighs

• For men, bubbles on the glans and shaft of the penis and anal area

• Confusion

• Neck stiffness   

What other tests might I have along with this test?

Your doctor will also do a medical history and a physical exam to help diagnose HSV. You may also need blood tests or X-rays.

What do my test results mean?

Many things may affect your lab test results. These include the method each lab uses to do the test. Even if your test results are different from the normal value, you may not have a problem. To learn what the results mean for you, talk with your health care provider. 

How is this test done?

This test requires obtaining a sample of your cerebrospinal fluid. Your doctor will take the sample through a lumbar puncture, using a thin needle. The needle will be pushed into your lower back, and fluid will be removed.

Does this test pose any risks?

A lumbar puncture, or LP, carries these possible risks:

• Headaches

• Infection

• Bleeding

• Tumors

• Numbness  

What might affect my test results?

Your normal activities won't affect your test results.

How do I get ready for this test?

You don't need to prepare for this test. But be sure your doctor knows about all medicines, herbs, vitamins, and supplements you are taking. This includes medicines that don't need a prescription and any illicit drugs you may use.