Your story is like mine. No family history, no known cause, except UTIs, and physicians ruled out that anti-biotic as a probable cause. I have researched constantly and I still feel as if I am wandering in the wilderness. as far as the medical profession and my condition.
No family history,
I had to fight to get care for what was originally diagnosed as CKD 3 (a or b). Now it seems I am really at Stage 2, Creatine 9, GFR 64. But six months ago, when this was first casually mentioned, my hospital records showed me as having a GFR of 50. (!) And, the advice was that I did not have to "do" anything. I have become knowledgeable about numbers, diet, and endless details about all aspects of this disease, as well as medical research, and diet. Especially diet.

I have researched and purchased several books and regularly visit a couple of websites. One book I bought is by Shelley Manning, altho I keep confusing her with Mary Shelley, who wrote Dracula.

Immediately on learning, by accident, that I was Stage 3 (remember I actually sort of at Stage 2) I began to read up and learn all I could.

Physicians tell you that at Stage 3, you do not need to change a thing. A crusade needs to form around telling people to ignore their doctors' advice and begin to make changes immediately. That is if you actually HAVE a kidney specialist; I had to fight my way to that as well, and after a brief 15-minute chat, I changed to another kidney specialist who actually sat down and explained it to me. Still, she told me not to worry about doing anything at this stage. Again, I think it is my age...

I receive vague assurances, no one has given me advice about diet, I changed kidney doctors because of lack of interest, and forced myself onto the hospital nutritionist. Meanwhile, I have researched everything I could find and followed all the tendrils that lead to and from CKD. God help the person who is not assertive and diligent about a CKD diagnosis.

Looking back, the most stunning part is the continued response from medical professionals that I do not have to "do" anything. Partly, I believe, this is because I am older, so since CKD is slow-moving, and I am supposed to die before I will approach the dialysis stage. Well, that was never going to be an option for me!

Get acquainted with all the kidney advice and dietary knowledge you can find. Change your diet, exercise, work toward lowering your GFR and other numbers. Haunt the web. Read comments and advice on sites like this one. Knowledge is power.

And, by the way, people with Kidney Disease do not die from Kidney Disease. They die from heart attacks. Aim for moderate exercise every day if possible, for 30 minutes. I am thin anyway, and I hate exercising, but I am trying to become diligent.

My take-away? Begin on day one to change your diet and fight.