I've had all kinds of vitamin D issues. Mine goes up and down like a rollercoaster. The doc had me taking 50,000 units a week for a while. Now I take 1000 IU per day.
There seems to be a link between AI issues and vit. D deficiency. Of course, it doesn't help that many of us have to avoid the sun, too. There have been some threads here about it, and I've seen a lot of discussion about it on the Sjogren's site.