Antibody titer blood test
Titer - antibodies; Serum antibodies
Antibody titer is a laboratory test that measures the level of antibodies in a blood sample.
Antibodies
An antibody is a protein produced by the body's immune system when it detects harmful substances, called antigens. Examples of antigens include micr...
How the Test is Performed
Blood sample is needed
Venipuncture is the collection of blood from a vein. It is most often done for laboratory testing.
How to Prepare for the Test
No special preparation is necessary for this test.
How the Test will Feel
When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or slight bruising. This soon goes away.
Why the Test is Performed
The antibody level (titer) in the blood tells your health care provider whether or not you have been exposed to an antigen or something that the body thinks is foreign. The body uses antibodies to attack and remove foreign substances.
Antigen
An antigen is any substance that causes your immune system to produce antibodies against it. This means your immune system does not recognize the su...
In some situations, your provider may check your antibody titer to see if you had an infection in the past (for example, chickenpox) or to decide which vaccines you need.
The antibody titer is also used to determine:
-
The strength of an immune response to the body's own tissue in diseases such as systemic lupus erythematosus (
SLE
) and other
autoimmune disorders
SLE
Systemic lupus erythematosus (SLE) is an autoimmune disease. In this disease, the body's immune system mistakenly attacks healthy tissue. It can af...
Autoimmune disorders
An autoimmune disorder occurs when the body's immune system attacks and destroys healthy body tissue by mistake. There are more than 80 types of aut...
- If you need a booster vaccine
- Whether a vaccine you had before helped your immune system protect you against the specific disease
-
If you have had a recent or past infection such as
mononucleosis
or
viral hepatitis
Mononucleosis
Mononucleosis, or mono, is a viral infection that causes fever, sore throat, and swollen lymph glands, most often in the neck.
Viral hepatitis
Hepatitis is swelling and inflammation of the liver.
Normal Results
Normal values depend on the antibody being tested.
If the test is being done to look for antibodies against your own body tissues, the normal value would be zero or negative. In some cases, a normal level is below a specific number.
If the test is being done to see if a vaccine fully protects you against a disease, the normal result depends on the specific value for that immunization.
Negative antibody tests can help rule out certain infections.
Normal value ranges may vary slightly among different laboratories. Talk to your provider about the meaning of your specific test results.
What Abnormal Results Mean
Abnormal results depend on which antibodies are being measured.
Abnormal results may be due to:
- Autoimmune disease
- Failure of a vaccine to fully protect you against a certain disease
- Immune deficiency
- Viral infections
Risks
Veins vary in size from one person 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.
Risks associated with having blood drawn are slight but may include:
-
Excessive
bleeding
Bleeding
Bleeding is the loss of blood. Bleeding may be:Inside the body (internally) Outside the body (externally)Bleeding may occur:Inside the body when blo...
-
Fainting
or feeling lightheaded
Fainting
Fainting is a brief loss of consciousness due to a drop in blood flow to the brain. The episode most often lasts less than a couple of minutes and y...
- Hematoma (blood accumulating under the skin)
- Infection (a slight risk any time the skin is broken)
References
Kroger AT, Pickering LK, Wharton M, Mawle A, Hinman AR, Orenstein WA. Immunization. In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases . 8th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 321.
McPherson RA, Riley RS, Massey HD. Laboratory evaluation of immunoglobulin function and humoral immunity. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods . 23rd ed. Philadelphia, PA: Elsevier; 2017:chap 46.
-
Antibody titer - illustration
The antibody level in the blood is a reflection of the body's past experience or exposure to an antigen, or something that the body does not recognize as self. Every living cell has different protein markers on its surface called antigens, and the body's immune system identifies those cells that are not part of its structure by those surface proteins.
Antibody titer
illustration
-
Antibody titer - illustration
The antibody level in the blood is a reflection of the body's past experience or exposure to an antigen, or something that the body does not recognize as self. Every living cell has different protein markers on its surface called antigens, and the body's immune system identifies those cells that are not part of its structure by those surface proteins.
Antibody titer
illustration
-
Systemic lupus erythematosus
(In-Depth)
Review Date: 5/17/2016
Reviewed By: Laura J. Martin, MD, MPH, ABIM Board Certified in Internal Medicine and Hospice and Palliative Medicine, Atlanta, GA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.