They form on the kidneys and rupture and it's painful. Is it dangerous? My 65 Yr old sister has disease, was sick and in lots of pain yesterday, had to go to ER. She was given Naproxon, and another pain pill, and was told her cysts were rupturing on her kidneys, but tonight she's having the same problem but in a different spot in her stomach. Wonder if it's another rupture cysts She's not going to ER again. I'm worried about her.They've ruled out palacuetis.Stomach infection if you eat corn or certain other foods, but I didn't spell it right,