I cant offer advice as such, but sympathy & hand holdind as I'm going through similar myself at the moment, though I was too scared didn't get the actual figures, only that its CKD & I've to have more tests & see the Renal Unit.
I've a history of kidney trouble - damage die to recurring infections years back, but I turned it around by changing my diet, so I thought it was all behind me, so its come as a bit of a shock, so I'm currently sticking my head in the sand a bit
Have they tested for Diabetes, Thyroid & Lupus ?? - They can be the cause of it & if controlled will stop it getting worse - I'm presuming you also have high BP - my GP said its chicken & egg - CKD causes HBP & vice versa, so controlling that is important & they can give you HBP pills that help protect your kidneys - my BP is currently doing well on Losartan
The other thing I've learned from my past history is that kidneys feel the cold badly, so keep them warm - & cranberry juice is great for keeping infections at bay - I dont want to say anything on diet, as from what I'm reading its low protein/high carbs, which would be very bad if your cause was diabetes IYSWIM
you have my sympathy