Ok so it all started out with a staph infection, with where the medication gave me a yest infection, then a bladder infection, and i went to the doctor and apparently i have nephritis. Im only 13, I have been having lower abdominal pain, and slite pain in my back sides. I have had two other surgery's, but they weren't for nephritis they were for appendix, and gallbladder. Maybe i have something wrong with my amune systme? Why do i keep getting sick? and what excatly is nephritis?