Hello nandyassweetasacandy , welcome to healthcaremagic.com Your case scenario is suggestive of an infective etiology may be that started with your thyroid and some how did manage to affect / infect your kidneys may be , though it happens rarely. You did say the biopsy done for your kidneys are within normal limits , it rules out any underline chronic kidney disease for you, so your swelling of legs if it is of immediate onset and you never had such symptoms before could be attributed to the acute nephritis / pyelo nephritis of your kidneys. So controlling of your infection may actually will treat the infective component in kidney and the proteinuria will subside by itself. Since you have not mentioned i will assume you don t have any co morbid conditions like diabetes , hypertension, cadiac ailments or recurrent urinary tract infections which can be responsible for such diseases. I would like you to undergo serum uric acid estimation if have pain in your legs along with swelling of your legs but please consult with your primary physician first he has a better clinical picture you than me. We do recommend ACE inhibitor for our cardiac , hypertensive and diabetic patients which does decrease the micro albuminuria in urine but their etilogies are different from your so i will not advocate that medications for you provided you are free from such co-morbid conditions