words in apostrophes

Hi,

Lately I am seeing more phrases with words in apostrphes in the place where I think you will usually find typical adjectives and want to know whether it can be just about anything and if it has any effect on the choice of the article that might be needed to be placed?

e.g.

"seuljjaing" syndrome (shouldn't it normally be "the 'seuljjgang' syndrome" since syndrome is countable ?)