The danger of this disease is that the sufferers rarely, if ever, know that they have contracted it, and continue about their merry way under the assumption that EVERYONE ELSE is the problem.
This condition, if left untreated, can radically alter the carrier's demeanor, to include any of the following: a complete devolution to child-like behavior, temper tantrums, and/or fits of narcissistic rage.
When confronted with an individual suspected of harboring Special Snowflake Syndrome, one's best course of action is to run away. Further attempts at educating the carrier on the reality of their condition (e.g., quoting Tyler Durden: "You are not special. You are not a beautiful or unique snowflake. You're the same decaying organic matter as everything else.") will likely prove futile, and potentially hazardous to the informer.
-Hell if I know, but she definitely had Special Snowflake Syndrome.
See also: tumblr cliche, First world problems.