I have NEVER heard that account before. Unfortunately, many people have developed kidney issues long after their Lupus diagnosis. I do not want to scare you or make you think that you do, indeed, have kidney issues. I am merely pointing out the falsehood of that particular statement!
I hope that your biopsy is negative for any kidney damage. But, even if it is positive, know that there are treatments available that will reduce your symptoms and possibly stop any further damage. Try not to obsess about this or to cause yourself undue stress; that is our worst enemy.
I wish you the very best and please keep us posted about your results.
Peace and Blessings
Look For The Good and Praise It!