Sjögren Antibody (Blood)

SS-A (or Ro), SS-B (or La)  

Sjögren disease is an autoimmune condition that makes it hard for your glands to make enough moisture. The condition causes discomfort by drying out mucous membranes, including the ones in the mouth, eyes, nose, lungs, and vagina. Sjögren may also affect the joints, kidneys, and the nervous, vascular, respiratory, and digestive systems.

To help diagnose the condition, healthcare providers use this blood test to check for Sjögren-related autoantibodies. These are substances in the blood that attack the body's tissues instead of foreign substances like bacteria.

Sjögren disease is a common problem. Women are affected more than men. Sjögren disease often happens along with other autoimmune disorders, such as rheumatoid arthritis or lupus. 

You may need this test if you have abnormal liver tests or show symptoms of Sjögren disease. These include:

• Dry eyes or corneal ulcers

• Gritty feeling in the eyes

• Feeling of dryness in the mouth and trouble swallowing dry food

• Heartburn and reflux

• Arthritis

• Muscle pain

• Repeated bouts of bronchitis and pneumonia

• Trouble focusing and "brain fog"

• Numbness and tingling in the feet and toes

• Dry skin

• Sore tongue

• Vaginal dryness 

You may need other tests to help diagnose Sjögren disease. These include:

• Schirmer test to measure eye dryness

• ANA (Anti-Nuclear Antibody)

• RF (Rheumatoid Factor)

• ESR (Erythrocyte Sedimentation Rate)

• Salivary flow study

• Salivary scintigraphy

• Salivary gland biopsy

Test results may vary depending on your age, gender, health history, and other things. Your test results may be different depending on the lab used. They may not mean you have a problem. Ask your healthcare provider what your test results mean for you.

A number of conditions can cause dryness of the eyes and mouth, but if you have certain antibodies in your blood, it means you may have Sjögren disease. These autoantibodies include:

• SS-A, also called Ro

• SS-B, also called La

• Antinuclear antibody, or ANA

A normal test doesn't show any antibodies to Ro or La. But people with Sjögren disease don't always have these autoantibodies. 

The test is done with a blood sample. A needle is used to draw blood from a vein in your arm or hand. 

Having a blood test with a needle carries some risks. These include bleeding, infection, bruising, and feeling lightheaded. When the needle pricks your arm or hand, you may feel a slight sting or pain. Afterward, the site may be sore. 

Other conditions can cause a positive test for Ro or La, including lupus and vasculitis.

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