A 23-year-old woman presents to the emergency room for a self-inflicted laceration of her distal volar forearm. The patient states she knew her boyfriend was having sexual thoughts about the woman from the grocery store, prompting her decision to cut her own wrist. In the emergency department, the bleeding has stopped and the patient is currently medically stable. When interviewing the patient, she is teary and apologizes for her behavior. She is grateful to you for her care and regrets her actions. Of note, the patient has presented to the emergency department before for a similar reason when she was struggling with online dating. The patient states that she struggles with her romantic relationships though she deeply desires them. Her temperature is 98.6°F (37°C), blood pressure is 112/71 mmHg, pulse is 73/min, and respirations are 14/min. On physical exam, you note a frightened young woman who is wearing a revealing dress that prominently displays her breasts. You tell the patient that she will have to stay in the psychiatric emergency department for the night which makes her furious. Which of the following personality disorders is the most likely diagnosis?
Borderline
Dependent
Avoidant
Antisocial
Borderline
This patient is presenting with a suicide attempt, unstable relationships, and emotional lability suggesting a diagnosis of borderline personality disorder.

Borderline personality disorder classically presents with emotional lability, and intense, unstable relationships. These patients fear abandonment and will often engage in self-harming behavior like cutting and suicide attempts. The main defense mechanism these patients employ is splitting, in which patients divide the world into dichotomous categories where people are either all good or all bad. This personality disorder is associated with mood disorders and substance use. The treatment of choice for these patients is long-term dialectical behavioral therapy and mood stabilizers.

Leichsenring et al. review the evidence regarding the treatment of patients with borderline personality disorder. They discuss no specific form of psychotherapy is superior to others. They recommend starting any form of psychotherapy for these patients to improve outcomes.

Incorrect Answers:
Answer A: Antisocial personality disorder presents with aggressive, criminal behavior. These individuals do not conform to social norms or rules and violate the rights of others. Patients often are not amenable to behavioral modification and therefore incarceration may be necessary in order to protect the rights of others.

Answer B: Avoidant personality disorder presents with excessive shyness and hypersensitivity to rejection. These patients fear social interaction though they strongly desire relationships. Cognitive behavioral therapy can be used in order to encourage these patients to be more open to seeking out relationships.

Answer D: Dependent personality disorder presents with submissive and clingy behavior. They often have a need to be cared for and will be very agreeable and dependent on others. This can be harmful as patients may stay in abusive or degrading relationships due to a fear of being alone. Treatment is with cognitive behavioral therapy.

Answer E: Histrionic personality disorder presents with colorful and exaggerated attention-seeking behavior. These patients will often employ sexuality to draw attention to themselves. Though this patient is displaying her breasts and wearing seductive clothing, her history of self-harm behavior and unstable relationships suggests a diagnosis of borderline personality disorder.

Bullet Summary:
Borderline personality disorder presents with emotional instability, unstable relationships, and self-harming behavior.