Actress Kristen Johnston Diagnosed With Lupus

3rd Rock from the Sun alum Kristen Johnston revealed on Facebook that she's been diagnosed with a rare form of lupus. Although the actress, currently starring in TV Land's The Exes, says she's "gonna be fine," the illness caused her to miss two episodes, during which Leah Remini will guest star.

Johnston initially didn't want name the auto-immune disorder she'd been diagnosed with, instead merely explaining how her recent health issues meant that she wouldn't be in a couple of upcoming episodes of her show.

"I've been really, really sick since early Sept.," Johnston posted Tuesday. "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. Lying down I'm fine, which is great for writing or killing time on social media (thank you all!!), but it's kind of disasterous [sic] when you're in a sitcom that requires tons of physical comedy."

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She explained that she shot as much of The Exes as she could but had to "begrudgingly" miss two episodes, during which Remini will guest star as Stuart's sister. Remini's first episode airs Jan. 1, Johnston said, adding that Remini's so funny the audience won't even miss her.

Johnston went on to explain that it took four months and 17 doctors, including two weeks at the Mayo Clinic in November, for her to be diagnosed with lupus myelitis, "meaning my immune system has decided to go rogue & attack my muscles. The good news: I'm finally on the right treatment, feeling better & back at work!"

Johnston said she didn't mention her health problems because she didn't want people overreacting and diagnosing her, but she thanked everyone at The Exes for being "so patient, understanding, loving & supportive."

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"It's true that when you're sick, you find out who your real friends are, and these people, along with so many others, like ..... Oh Crap. This is starting to sound like a dreadful acceptance speech, so I'll just say you know who you are. Thank you & I love you," she wrote.

She finally revealed the identity of her auto-immune disorder on Wednesday, after posting on Tuesday that she intentionally didn't name it.

"Oh for f---s sake. I'm not trying to be 'coy,' 'relevant" or 'get attention' -- I just was diagnosed 2 days ago with a rare form of Lupus called 'Lupus Myelitis' -- google it. I'm not on my death bead ... far from it," she wrote.

"I just wanted to have a few weeks of privacy to navigate it & receive treatment," she added.

Hilary Lewis