The GMC is requiring a doctor who tweets to indentify themselves:
'Tweeting doctors should identify themselves by name' -
DOCTORS must identify themselves by name on Twitter if their profile alludes to their profession, new guidance suggests.
The reason being:
The guidance says any material written by authors who call themselves doctors is "likely to be taken on trust", and tweets posted by clinicians should maintain public trust in doctors.
You could say this is hard to police, but if investigated for other matters, an anonymous twitter account could easily be found via your PC or email, and thus land you in trouble.

Will Ireland or other professional bodies follow suit ? Are people comfortable that doctors are a special case and should thus regulate themselves ? I don't like the look of this at all...