Kim Kardashian Just Tested Positive For Lupus Antibodies—But What Does That Mean?

In the season 17 premiere of Keeping Up With the Kardashians, Kim Kardashian West received some pretty scary health news—and fans still aren't sure exactly what's going on with her.

The 38-year-old went into detail about some concerning symptoms she'd been having lately. "I’ve been feeling so tired, so nauseous and my hands are really getting swollen,” she explained. “I feel like I literally am falling apart. My hands are numb.”

Once carpal tunnel syndrome and pregnancy were ruled out as possible causes, Kardashian West grew worried about what else could be causing her symptoms. “It’s starting to really worry me. I really have to look into this," she said on the show. "Based on the symptoms, it looks like I have rheumatoid arthritis. It’s so scary. I have to go to the doctor and see what’s going on because I can’t live like this.”

That doctor visit led to blood work—and Kardashian West got her results at the end of Sunday night's episode. On a phone call with her doctor, she found out her "antibodies are positive for lupus and rheumatoid arthritis"—after which, she scheduled an appointment to get ultrasound scans on her hands and joints, per her doctor's suggestion. Kris Jenner, Kardashian West's mother, attempted to comfort her through the news, telling her daughter to "stay really positive until we get some results.”

So what exactly is going on with Kardashian West? Here's what's known so far.

What are lupus and rheumatoid arthritis—and how are they diagnosed?

Before diving right in, a little background on the two conditions Kardashian West was tested for: lupus and rheumatoid arthritis.

Lupus, aka systemic lupus erythematosus (SLE), is an autoimmune disease that affects the body’s ability to tell the difference between foreign invaders (think: the flu) and healthy tissue. About five million people have lupus, according to the Lupus Foundation of America. A few symptoms of the condition include joint pain, swelling, stiffness, and a rash on the face.

Rheumatoid arthritis is also an autoimmune condition (so it also affects the body’s ability to defend itself). Rheumatoid arthritis causes swelling and joint pain. In the US alone, about 1.5 million people have rheumatoid arthritis, per the Arthritis Foundation. Symptoms include joint stiffness, swollen joints, and fatigue.

Neither lupus nor rheumatoid arthritis can be diagnosed with a single blood test. They're both somewhat difficult to diagnose because symptoms of both conditions can mimic those of a number of other conditions. Blood tests, urine tests, and biopsies can help your doctor diagnose lupus, per the Lupus Foundation of America; while blood tests, imaging tests, and physical examinations can help doctors diagnose rheumatoid arthritis, per the Arthritis Foundation.

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So what does it mean when antibodies test positive for lupus and rheumatoid arthritis?

Let's make this clear from the get-go: Just because Kim's "antibodies are positive for lupus and rheumatoid arthritis," doesn't mean she has either disease, Sara Tedeschi, MD, MPH, assistant professor of medicine at Harvard Medical School, tells Health.

In general, "antibodies are proteins our bodies form in response to something perceived as foreign," says Dr. Tedeschi. Basically, they work to protect our bodies from foreign invaders like bacteria and viruses.

Sometimes, however, these antibodies can form to attack normal, healthy cells—as is the case with autoimmune diseases like lupus and rheumatoid arthritis—Brad Rovin, MD, director of the division of nephrology at the Ohio State University Wexner Medical Center tells Health.

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But again, merely testing positive for those antibodies doesn't necessarily indicate disease. Dr. Tedeschi explains that the antibodies that reflect the possibility of rheumatoid arthritis or lupus can also be linked to other types of disease. She adds that antibodies of lupus "can be positive at a low level in up to 25% of healthy, young people."

Still, doctors will have to further investigate to figure out what's causing Kim's symptoms. Dr. Tedeschi says there's no one "next step" in this process, though Kardashian West's doctors have already suggested an ultrasound of her hands and joints to further help her diagnosis. Again, that's entirely specific to her doctors and her condition.

But as far as Kardashian West's current test results go, "the presence of these antibodies alone does not mean a person definitely has lupus or rheumatoid arthritis," says Dr. Rovin, so nothing is concrete until Kim does further testing. Apparently, Kardashian West's fans will have to continue Keeping Up with her—and her health issues—to find out more.

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