It means one of two things: It means you either have a severe infection by some kind of psuedomonas bacteria, or it idicates that your body's level of calcium is extremely high. Whether it be the first or the second thing they are both lethal. I recommend you go to the ER immediately. If its your calcium level, then it could cause your heart to stop which would kill you. If its a bacterial infection, then the infection has reached very sever level and needs to be treated immediately or it could lead to toxic shock syndrome, which will also kill you. Anyways 99% of the time it means your about to die, so I would go to the ER like asap. Now if you've been eating lots of foods with blue dies than this can happen. Also there are certain medicines which can cause blue urine. But unless you are on a special medication that turns it blue, I would go get it checked out.