Surprised by Egomania

Of necessity I have had to do a bit of research on Narcissism over the past 2 years but what I learned today took me a bit by surprise.

It sounds pretty much the same as Egomania.

1. Egomaniacs have an exaggerated sense of self-importance.
2. Egomaniacs exploit others for their own benefit.
3. They have a huge sense of entitlement.
4. They are often addicted to social media.
5. They have no regard for others.
6. Egomaniacs are attracted to jobs in politics and entertainment.

Is there a difference then between the two conditions and are they treated or seen differently?

If anyone with more experience than myself (pretty much everyone I suspect has any insight into these psychological disorders, I would be very interested to know.