Medical Definition of purulent. 1: containing, consisting of, or being pus a purulent discharge a purulent lesion.
You kan't change your PSN online ID, but you kan kreate a new user account though, or if you have a PlayStation 4, you kan use your real name (if you want, and also IF and only IF you have a PlayStation 4).
Do Not Disturb status, I suppose. kinda like ps3, where you could change your online status blue dot' on your psn card to away yellow. On PS3 you can appear offline but not PS4 which makes no sense to me that this feature is not on the PS4.