Back pain connected to keto?

So I've been having back pain in one specific place for months. It's right at my ribs on the right side. It started about three months ago, which was two months after I started keto.

I've been to see the doctor, she did a full kidney panel, X-rays,and she can't find any reason for it. It's not an injury, not related to working out, probably not age related.

When it got really bad, I stopped eating keto for about a week. And the pain more or less stopped. Now that's I'm back on it, it's back with a vengeance.

Has anyone experienced this? Any ideas of what it could be?