During a recent interview on Larry King Live on CNN, singer Lady Gaga stated that she tested borderline positive for lupus but that, as of right now, she does not have lupus.

There are many challenges in confirming whether a person has lupus. Lupus symptoms can be unclear, can come and go, and can change over time. It may take months or even years for doctors to piece together evolving symptoms to accurately diagnose lupus. And the symptoms may be related to another condition entirely.

No single laboratory test can determine whether a person has lupus.

A variety of laboratory tests are used to detect physical changes or conditions in the body that can occur with lupus. Each test result adds more information to the body of evidence that a doctor uses to determine if a person has lupus. However, lupus cannot be diagnosed solely on lab work.

- Test results that suggest lupus can be due to other illnesses, or can even be seen in healthy people.
- A test result may be positive one time and negative another time.
- Different laboratories may produce different test results.

Physicians use a list of 11 criteria to help diagnose lupus. A person needs to satisfy at least 4 out of the 11 criteria before the diagnosis can be pinpointed. Of the 11 criteria, 7 relate to symptoms, and 4 have to do with lab tests.

The anti-nuclear antibody (ANA) test is used as a screening test for lupus. We know that 95 percent of people with lupus have a positive ANA. Therefore, if a person has symptoms of systemic lupus but their ANA test is negative, that's generally regarded as pretty good evidence against lupus being the explanation for the symptoms they are having.

If on the other hand, if the ANA test comes back positive, that IS NOT proof of lupus. The positive ANA is only an indicator; it is not diagnostic. A positive ANA can be found in a number of illnesses and conditions. In fact, many people may have positive lupus tests-particularly the anti-nuclear antibody test-and yet they do NOT have the disease.

All lab tests have normal values. If a test result comes back and the value is at the upper limit of normal, this is often referred to as being on the border or borderline. These results are often very difficult to interpret; and the assessment of its importance is dependent on meeting other criterion.

A lupus diagnosis is made by a careful review of:

- a person's current symptoms,
- laboratory test results,
- medical history, and
- the medical history of close family members (grandparents, parents, brothers and sisters, aunts, uncles, cousins).

All of this information may be necessary for a doctor to make a diagnosis of lupus because, for a number of reasons, laboratory tests alone cannot give a definite "yes" or "no" answer.

NOTE: The Lupus Foundation of America is currently funding research to revise and validate the diagnosis criteria for lupus.

Additional Resources

Learn more about symptoms of lupus

Learn more about laboratory test used to diagnose lupus

Check out our interactive tool and symptoms checklist

Learn more about lupus

Source
Lupus Foundation of America