'The Exes' Kristen Johnston reveals rare autoimmune disorder diagnosis

kristen-johnston-lupus-gi.jpg "The Exes" star Kristen Johnston will be absent from a pair of upcoming episodes of the TV Land series, prompting the sitcom vet to open up about the series reason behind her absence.

Taking to her Facebook on Tuesday (Dec. 17) with a lengthy blog post, Johnston revealed that she's been quite ill for some time now and has recently been diagnosed with a rare autoimmune disorder.

"Hey guys, I've put this off as long as possible, but it's time for me to be upfront with you about something that's been going on with me," she begins. "Short(ish) version: I've been really, really sick since early Sept. 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 admits that, though she tried to shoot as much of "The Exes" as possible, she eventually had to "begrudgingly" miss the pair of episodes. "Here's how much I love you. Before you even had a chance to wonder 'Hey! Where'd that big mouthy blonde gal go?' I thought I'd tell you.....This lucky lady spent 2 fun-filled weeks in November partying at The Mayo Clinic."

It was through her stay at Mayo that, after four months and 17 doctors, Johnston was finally diagnosed with the unnamed disorder. "The good news," she writes, "I'm finally on the right treatment, feeling better & back at work!"

"I gotta say, TV Land and everyone at 'the exes' have been just amazing, all of them," she adds. "So patient, understanding, loving & supportive.."

While her initial announcement didn't name the disorder, a subsequent Facebook post on Wednesday clarified that she had been diagnosed with a rare form of Lupus called Lupus Myelitis.

"The Exes" airs Wednesdays at 10:30 ET on TV Land.
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