In 2011, the elder Williams sister was diagnosed with Sjogren’s syndrome, an autoimmune disease that dries out the mouth and eyes, and can also sap strength and cause joint and muscle pain, coughing, and limb numbness.
Williams went through a series of misdiagnoses for years, The New York Times reported. Sjogren’s is difficult to pinpoint since it has so many seemingly unrelated symptoms that could also be caused by a whole host of other diseases, including rheumatoid arthritis and exercise-induced asthma.
More than 4 million people in the U.S. have the disease, according to the Sjogren’s Syndrome Foundation. Nine out of 10 are women. Symptoms begin when the body’s immune cells attack its own tear and saliva glands, according to the National Institute of Arthritis and Musculoskeletal and Skin Diseases.
Half of the time, Sjogren’s occurs with another autoimmune disease like rheumatoid arthritis or lupus.
“It causes so many symptoms, sometimes it’s hard for a specialist to get the big picture,” Dr. Frederick Vivino, a Sjogren’s syndrome expert at the University of Pennsylvania School of Medicine, told The New York Times in 2011.
What’s worse, Vivino explained, is that “most of the patients do not look like they have a chronic illness. Because they look a lot better than they feel, some of our patients have been told they’re hypochondriacs or they’re depressed or they are experiencing these symptoms due to menopause, and they just accept that. That’s why people go years before being treated.”
Early diagnosis can prevent future severe complications from the disease, the Sjogren’s Syndrome Foundation says. Treatment often tackles each symptom of the disease separately: using artificial tears for dry eyes, drinking lots of water for dry mouth, and taking prescription medications for other autoimmune diseases that may occur in concert. Williams told CNN last year that she switched to a vegan diet and started a new exercise regime to help her overcome the syndrome, but there’s no hard evidence that such interventions work. (So far, clinical trials have yet to yield any effective treatments for the syndrome as a whole.)
Though Venus was the top Williams when they started playing tennis, her little sister has since eclipsed her with 15 wins in their 26 matchups. Part of that was due to the years Venus spent with a troubling constellation of mysterious symptoms, trying to find, diagnose, and treat what she eventually learned was Sjogren’s.
This year, there’s extra tension since Serena will achieve her first Calendar Grand Slam if she wins the U.S. Open, given that she already won Wimbledon, and the Australian and French Opens.
Their quarterfinal U.S. Open match will be broadcast on ESPN at 7 p.m. ET on Sept. 8.
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