I've not encountered your particular problem, but my daughter did. I do know that Prednisone is the fastest and most successful drug to counter kidney damage due to Lupus. Yes, the side effects are scary, but sometimes the alternative is worse (like compete renal failure!).
Do talk to the kidney specialist to see if there is an alternative treatment that works as well as Prednisone. I wish you the very best and I hope that you find some answers that work for you.
Peace and Blessings
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