At least five of the following are necessary for a diagnosis (as with
many DSM diagnoses, they must form a pervasive pattern; for example, a
person who shows these criteria only in one or two relationships or
situations would not properly be diagnosed with NPD):
has a grandiose sense of self-importance
is preoccupied with fantasies of unlimited success, power, brilliance,
beauty, or ideal love
believes that he or she is "special" and unique and can only be
understood by other special people
requires excessive admiration
strong sense of entitlement
takes advantage of others to achieve his or her own ends
lacks empathy
is often envious or believes others are envious of him or her
arrogant affect.
POSSIBLE CAUSES:
The etiology of this disorder is unknown.
Some sources suggest that narcissistic personality disorder may be an
infantile, defensive personality structure in response to abuse and
trauma, usually developing in early childhood or early adolescence.
They suggest that narcissistic personality disorder may be a
maladaptive defense of the abused child's or adolescent's emotional
splitting, resultant cognitive distortions, and negative/hostile
worldview.
Some think that caregiver deprivation at approximately 36 months of
age is a major risk factor for the later development of this disorder.
Conversely, some theories suggest that the disorder can manifest
itself in people who have been over-indulged and doted on by their
parents.