There are seronegative types of inflammatory arthritis, meaning no biomarkers in the blood. In that case it’s a clinical diagnosis—based on what doctors can observe and what you feel, if it responds to empiric (“trial and error”) treatment, and ruling out other conditions. I have such a condition.

Statins are associated with arthralgias but you probably want to check with your doctor about that because they can run tests to see if the statins may be causing muscle pain. And it could increase your risk of whatever the doctors are trying to help you prevent on a statin. There are other cholesterol drugs that have a different mechanism of action with less risk of arthralgia (my dad just started one because he developed inflammatory arthritis after a statin).

To your insurance question about IVIG, I don’t know. Others seem to have had a different experience, but for me, I’ve been to Mayo, Northwestern and Rush in Chicago and Johns Hopkins and no one except for 3 out of the 10 or more neurologists I saw, saw fit to order IVIG.

As I understood it, it’s indicated for autoimmune inflammatory conditions; if you don’t have evidence of an approved use or autoimmunity, it would be very difficult to get it approved because it’s extremely expensive. The first doctor who suggested it said it always gets pushed back to an appeal no matter what, for her.

But others seem to have accessed it more easily. My conditions are on the bubble because I have a seronegative inflammatory arthritis and evidence of an antibody called FGFR3, which is associated with SFN. But the test is considered experimental and so is IVIG. So it might get approved and may not. I’ve not pursued it yet.

Based on what I’ve experienced I think it sounds unlikely it would get approved if your diagnoses end up being OA and neuropathy.