hi
i am sorry about your long course of illness
first
let me clear this out
kidney infections do not cause hemorrhoids
they are two different conditions
that probably were noticed at the same time
i got the impression that the bumps you are developing are perianal
so they could be hemorrhoids causing the trouble
and so i would suggest you get yourself some stool softners
take high fiber diet and plenty of fluids
you could use sitz bath too
i dont think the trouble is because of the wearing of thongs
however it would be a good idea to avoid it while your hemorroids settle
once your hemorrhoids settle i suppose you can continue
hope you find this information pertinent and helpful
best of luck
get well soon