CSF agglutination test
This test looks at fluid from your spinal cord to find out if you have an illness called brucellosis.
Brucellosis is an infectious disease usually caused by handling animals or milk products infected with the brucella bacteria. If you have brucellosis, your body will make certain antibodies when it tries to fight these germs. Brucella antibodies can usually be found in your blood, liver, spleen, lymph nodes, or bone marrow.
In 2 to 7 percent of brucella infections, the bacteria infect the brain, spine, and other parts of the nervous system. This test looks at your cerebrospinal fluid (CSF) to confirm whether you have a brucella infection that has spread to your nervous system.
The disease is rare in the U.S., where fewer than 200 cases are reported each year. It's more commonly found in Latin America, the Middle East, and the Mediterranean, which is why it's often called Mediterranean or Malta fever. It's also called undulant fever, Bang's disease, and Gibraltar fever.
If brucellosis isn't treated after a few months, you may start to feel unusually weak or develop a fever and chills, headaches, backache, muscle and joint pain, and sweats. You may lose your appetite and appear anorexic. If untreated, the bacteria can sometimes damage the heart, joints, or central nervous system or cause recurring infections. If you are pregnant and have brucellosis, it may cause a miscarriage or infect your unborn child.
You may have this test if your doctor suspects that you are infected with brucella bacteria and that the infection has spread to your brain. This is especially true if:
You work in a slaughterhouse and have symptoms of the illness.
You work in a slaughterhouse, dairy, or farm and may have been exposed to the bacteria through a cut or open wound.
You hunt deer, wild pigs, or other animals and have symptoms of the illness. You may have been exposed while cleaning a carcass if you didn't wear gloves.
You have traveled to Spain, Greece, Mexico, or another country where brucellosis is common and have eaten unpasteurized milk, cheese, or ice cream.
You are a veterinarian and may have been exposed to the bacteria or accidentally injected yourself with the strain 19 vaccine used to inoculate cattle against brucella. People almost never develop brucellosis from contact with dogs unless their immune system is extremely weak from HIV/AIDS or another condition.
You work in a laboratory where you handle brucella bacteria.
Your doctor may also have ordered other tests before the spinal tap to find out whether you've been exposed to brucella bacteria.
Your doctor may also order an MRI scan if you have back pain to see if you have damage to your spinal cord
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.
Normal results are negative, meaning no brucella antibodies were found in your CSF. A negative result doesn't completely rule out an infection, though.
A positive result means that brucella antibodies were found and that you have an infection.
This test requires a sample of cerebrospinal fluid, which is taken through a lumbar puncture in your lower back. During this procedure, you either sit up and lean forward or lie down on your side. A health care provider inserts a needle into your spine and draws out a sample of fluid.
It's rare to develop complications after having this test. But potential risks include:
Nerve pain or numbness
Talk with your provider about the risks before the test. Be sure to tell your provider if you've had a seizure, increased pressure in your eyes, or other health problems. You may need to have other tests before having a lumbar puncture.
Having the test too soon after infection can affect your results.
You don't need to prepare for this test.