What is the diagnosis for a patient under 18 years old who exhibits conduct problems such as violating others' rights and impulsivity?

Conduct disorder is the appropriate diagnosis for a patient under 18 years old exhibiting conduct problems, including violating the rights of others and demonstrating impulsivity. This disorder is characterized by a pattern of behavior where the individual engages in activities that exclude societal norms and rules, which may include aggressive behavior, deceitfulness, theft, or serious violations of rules.

The age component is significant, as conduct disorder is specifically diagnosed in children and adolescents. If these behaviors were observed in adults, a diagnosis of antisocial personality disorder might be considered, but this is not applicable here since the patient is under 18.

While borderline personality disorder typically involves emotional regulation issues and unstable interpersonal relationships, it is also not diagnosed in individuals this young. Narcissistic personality disorder is characterized largely by a pervasive pattern of grandiosity, need for admiration, and a lack of empathy, which again does not fit the behavior profile described for this patient.

Consequently, conduct disorder is recognized as the appropriate diagnosis, as it directly addresses the clinical presentation of conduct problems in younger populations.