Kim Kardashian West "physically couldn't" use her hands due to psoriatic arthritis.
The 'Keeping Up with the Kardashians' star was diagnosed with the form of arthritis - which is caused by autoimmune disease psoriasis, which Kim also suffers from - after experiencing severe pain in her hands, and has now described the scary moment she realised she couldn't pick up her phone because her hands "hurt so badly".
Explaining her battle with psoriasis and psoriatic arthritis on her sister Kourtney Kardashian's lifestyle website Poosh, she said: "One night, I woke up to use the restroom and I physically couldn't pick up my phone. I thought it was strange but maybe I just slept on my hands weird and I was so tired, I didn't need to be checking my phone at that hour anyway. I fell right back asleep.
"I woke up that morning and I still couldn't pick up my phone. I was freaking out - I couldn't even pick up a toothbrush, my hands hurt so badly. I had worked out the day before and we did an arm day, so I thought maybe one of the exercises strained my hand. It didn't cross my mind that it could be anything serious. As the day went on, I got a bit more movement in my hands, but they really hurt from the inside - I felt it in my bones. Everyone assumed it was just my workout, but I knew this felt different."
Kim, 38, went to the doctor and was tested for rheumatoid arthritis and lupus, and was subject to an intense health scare when her test results came back positive, before her doctor discovered the positive results were actually false.
The star - whose health battle is being documented on her family's E! reality show - added: "I went to the doctor because then I thought I could possibly have rheumatoid arthritis. I knew I felt the pain in my bones, and after I Googled the possibilities, I was beyond scared.
"I had my blood tested for all possibilities, and it came back positive for rheumatoid arthritis and lupus. I immediately started to cry and felt so lost. You really can get in a crazy headspace when you think you have something. My doctor said I could have a false positive, and he wanted me to come back.
"I went back three days later, which felt like the longest three days of my life! It turns out those tests were a false positive and I did not have rheumatoid arthritis or lupus. I had psoriatic arthritis. It's similar to arthritis that can stem from psoriasis and it can come and go. It's still painful and scary, but I was happy to have a diagnosis. No matter what autoimmune condition I had, I was going to get through it, and they are all manageable with proper care."
Kim has learned to manage her psoriasis over the years, and hopes sharing her story will allow others to "feel confident" despite their health battles.
She wrote: "I've become extremely comfortable with my psoriasis. No matter where it is on my body, sometimes I am fine with showing it off and other times I don't want it to be a distraction, so I cover it up with body makeup.
"If you have psoriasis, you can't let it ruin your life or get the best of you. You have to do what you can to make sure you are comfortable but not let it take over.
"I hope my story can help anyone else with an autoimmune disease feel confident that there is light at the end of the tunnel."