I'm taking a vitamin D hormone right now for this. I went to the doctor several months ago. I had a lot of pain at my knees and my skin was itchy. My eyes were red a lot too. I honestly couldn't make any sense of what was going on.
It turns out it was calcification because my PTH hormone was not working right. This is the hormone that maintains calcium levels in the body. The vitamin D I'm taking helps this hormone work correctly.
I'm feeling better now, but I have to keep taking it.