Last night on Larry King Live, Lady Gaga, AKA Stefani Joanne Angelina Germanotta, told Larry “I have tested borderline positive for [lupus]… As of right now, I do not have it, but I have to take good care of myself.” We recently reported that Lady Gaga had been tested for lupus, but she did not reveal any results. “Gaga” has an aunt who died of lupus, and the disease tends to run in families. “Borderline” probably means that blood work she had done (see below) may have been slightly elevated above normal, or at the upper limit of what is normal, or that some tests may have been mildly elevated while others were normal.
According to the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS):
Diagnosing lupus can be difficult. It may take months or even years for doctors to piece together the symptoms to diagnose this complex disease accurately. Making a correct diagnosis of lupus requires knowledge and awareness on the part of the doctor and good communication on the part of the patient. Giving the doctor a complete, accurate medical history (for example, what health problems you have had and for how long) is critical to the process of diagnosis. This information, along with a physical examination and the results of laboratory tests, helps the doctor consider other diseases that may mimic lupus, or determine if you truly have the disease. Reaching a diagnosis may take time as new symptoms appear.
No single test can determine whether a person has lupus, but several laboratory tests may help the doctor to confirm a diagnosis of lupus or rule out other causes for a person’s symptoms. The most useful tests identify certain autoantibodies often present in the blood of people with lupus. For example, the antinuclear antibody (ANA) test is commonly used to look for autoantibodies that react against components of the nucleus, or “command center,” of the body’s cells. Most people with lupus test positive for ANA; however, there are a number of other causes of a positive ANA besides lupus, including infections and other autoimmune diseases, and occasionally it is found in healthy people. The ANA test simply provides another clue for the doctor to consider in making a diagnosis. In addition, there are blood tests for individual types of autoantibodies that are more specific to people with lupus, although not all people with lupus test positive for these and not all people with these antibodies have lupus. These antibodies include anti-DNA, anti-Sm, anti-RNP, anti-Ro (SSA), and anti-La (SSB). The doctor may use these antibody tests to help make a diagnosis of lupus.
Some tests are used less frequently but may be helpful if the cause of a person’s symptoms remains unclear. The doctor may order a biopsy of the skin or kidneys if those body systems are affected. Some doctors may order a test for anticardiolipin (or antiphospholipid) antibody. The presence of this antibody may indicate increased risk for blood clotting and increased risk for miscarriage in pregnant women with lupus. Again, all these tests merely serve as tools to give the doctor clues and information in making a diagnosis. The doctor will look at the entire picture—medical history, symptoms, and test results—to determine if a person has lupus.
Diagnostic Tools for Lupus