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OTRC: Kristen Johnston diagnosed with Lupus Myelitis, autoimmune disorder

Kristen Johnston talks to OTRC.com about the TV Land show 'The Exes' and her dog co-star, Pinky, in June 2012.

Kristen Johnston, formerly of "3rd Rock From The Sun" and current star of the TV Land show "The Exes," has revealed that she has Lupus Myelitis, a rare autoimmune disease.

The 46-year-old actress said on her Facebook page recently that she suffered from the symptoms for four months and went to 17 physicians before Los Angeles doctor Daniel Wallace identified her ailment on Monday.

She had initially said she was diagnosed with a rare autoimmune disorder, without naming it, and later revealed it to be Lupus Myelitis in a post late on Wednesday:

"I'm not on my death bead...far from it.I'm gonna be fine," she said. "I just wanted to have a few weeks of privacy to navigate it & receive treatment.

What is Lupus Myelitis? Lupus is a disease in which a person's immune system attacks cells in their body. According to Wallace's 2012 book, "The Lupus Book: A Guide for Patients and Their Families," Lupus Myelitis is a "rare but serious complication of lupus," which includes paralysis or weakness in limbs caused by inflammation around the spinal cord or blood clots in the spinal arteries. Treatment includes steroids and anti-clotting drugs.

Johnston said she had been "really, really sick" since early September.

"Full body muscle weakness to the extent that just walking difficult, stairs impossible and I even need a neck brace to hold my head up," she wrote. "Lying down I'm fine, which is great for writing or killing time on social media (thank you all!!), but it's kind of disastrous when you're in a sitcom that requires tons of physical comedy."

"Through the fall, I shot as much of The Exes as I possibly could, but eventually I did have to (BEGRUDGINGLY) miss two episodes," she added. "The good news: I'm finally on the right treatment, feeling better & back at work!"

(Pictured above: Kristen Johnston talks to OTRC.com about the TV Land show "The Exes" and her dog co-star, Pinky, in June 2012. Watch a video of the interview by clicking on the images.)