If a person experiences joint pain and tests positive for an antinuclear antibody (ANA) test, this may suggest the presence of an underlying condition causing joint problems and discomfort.
An ANA test analyzes the blood, looking for antinuclear antibodies. Antibodies are proteins the immune system produces to fight off substances such as viruses and bacteria. In people with autoimmune conditions, such as systemic lupus erythematosus (SLE) or rheumatoid arthritis (RA), the immune system produces ANAs even if a person does not have an infection.
If someone has an autoimmune condition, the ANA antibodies can attack the healthy cells in their body instead of viruses, bacteria, and other germs. This causes inflammation and swelling, which may lead to several symptoms, including joint pain.
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This article will review the ANA test, the meaning of its results, and the potential causes of joint pain.
A positive ANA test result
A positive ANA test may suggest a person has conditions,
Other symptoms of joint pain
The symptoms of joint pain can range from mild to severe and disabling and
- painful movement
- difficulties straightening or bending the joint
- stiffness
- swelling
- warmth
- numbness
- clicking, snapping, or grinding sound when moving the joint
- reduced or loss of motion
An ANA test is a blood test that looks for antinuclear antibodies in the blood. The presence of ANA antibodies may suggest or rule out several illnesses, which can significantly help doctors diagnose certain autoimmune conditions.
While a few antinuclear antibodies in the bloodstream are common, a large number may be a sign of an autoimmune disorder. However, high levels of ANA antibodies in the blood are not always a symptom of an autoimmune condition.
Clinical healthcare settings use several technologies capable of detecting ANAs, such as an immunofluorescent antibody or a multiplex assay. People can discuss with their doctor which technology to use, depending on factors such as insurance or availability.
How to prepare
There is no specific preparation to attend an ANA test. During the procedure, similar to other blood tests, a doctor collects a blood sample from a vein in the arm using a small needle. The doctor then sends the blood in a test tube for laboratory testing.
Apart from the little sting a person may experience when the doctor inserts the needle in their arm, the entire procedure is painless and usually takes about 5 minutes.
Results
The results of the ANA tests alone
A negative ANA test means that a person is less likely to have an autoimmune disorder as the doctors in the laboratory have not found antinuclear antibodies in the blood. However, this does not completely rule out the possibility of having an autoimmune illness.
A positive ANA test result means it has found antinuclear antibodies in the blood sample. This may be a sign of several conditions, such as:
- a viral infection
- an autoimmune disorder, such as SLE or rheumatoid arthritis (RA)
- other health conditions that can cause antinuclear antibodies, including cancer
However, a positive ANA test result is not always a sign of an underlying condition. About 1 in 3 healthy people over the age of 65 may have a positive ANA test result. Also, taking certain drugs may cause high antinuclear antibody levels.
If a person results positive for an ANA test, the healthcare professional may perform further examinations according to the symptoms a person experiences or their findings during the physical examination.
This may include additional tests to identify the specific type of ANA antibodies.
OA is more common in adults over the age of 40 and progressively affects the joints of the hand, wrists, hips, and knees. The progression of OA is typically slow and occurs due to the breakdown of the cartilage that separates the joints and acts as a cushion to prevent friction between the bones.
RA affects about 1.5 million people in the United States and occurs more frequently in biological women. RA causes inflammation in the joints, pain, and fluid buildup when the immune system attacks the membrane that lines the joints.
RA and OA are not the only conditions that can cause joint pain. Other illnesses or potential causes of joint pain
- injury
- overuse of the joint
- bursitis
- tendinitis
- chondromalacia
- fibromyalgia
- sarcoidosis
- rickets
- gout
- lupus
- certain infections, such as flu, hepatitis, or mumps
- joint or bone infection
- cancer
A person needs to contact a doctor if they experience joint pain that does not improve after a few weeks or worsens with at-home treatment.
Joint pain can occur because of several health conditions, including autoimmune disorders. An antinuclear antibody (ANA) test can detect if there are any ANA antibodies in the blood of a person who has reported joint pain. A positive ANA test can suggest an autoimmune condition. However, the result of an ANA test alone is not sufficient to diagnose an illness.
Autoimmune disorders are not the sole reason for joint pain. Overuse, injuries, and other health conditions, such as osteoarthritis, gout, or infections, can cause joint discomfort. A person needs to consult a doctor if they experience recurrent joint pain or worsening pain while resting their aching joint.