Lyme disease antibody

Definition

Lyme disease antibody tests are used to confirm the diagnosis of Lyme disease.

Alternative Names

Why the Test is Performed

The test is performed to help confirm the diagnosis of Lyme disease.

How the Test is Performed

Blood is typically drawn from a vein, usually from the inside of the elbow or the back of the hand. The site is cleaned with germ-killing medicine (antiseptic). The health care provider wraps an elastic band around the upper arm to apply pressure to the area and make the vein swell with blood.

Next, the health care provider gently inserts a needle into the vein. The blood collects into an airtight vial or tube attached to the needle. The elastic band is removed from your arm. Once the blood has been collected, the needle is removed, and the puncture site is covered to stop any bleeding.

In infants or young children, a sharp tool called a lancet may be used to puncture the skin and make it bleed. The blood collects in a small glass tube called a pipette, or onto a slide or test strip. A bandage may be placed over the area if there is any bleeding.

Technicians in a laboratory then look for the presence of Lyme disease antibodies in your blood using the ELISA test. Another test, called the Western blot, can confirm Lyme disease.

How to Prepare for the Test

There is no special preparation for the test.

How the Test Will Feel

When the needle is inserted to draw blood, some people feel moderate pain, while others feel only a prick or stinging sensation. Afterward, there may be some throbbing.

Risks

Veins and arteries vary in size from one patient to another and from one side of the body to the other. Obtaining a blood sample from some people may be more difficult than from others.

Other risks associated with having blood drawn are slight, but may include:

• Excessive bleeding
• Fainting or feeling light-headed
• Hematoma (blood accumulating under the skin)
• Infection (a slight risk any time the skin is broken)

Normal Results

Nonreactive or a very low serum titer (antibody count) is normal.

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

What Abnormal Results Mean

Only a positive Western blot test can confirm the diagnosis of Lyme disease. A positive ELISA can help confirm the diagnosis, but isn't enough by itself because other infectious diseases and some types of inflammatory diseases such as rheumatoid arthritis can give the same results.