Borderline personality disorder vs Bi polar disorder

Diagnostic questions around bipolar illness, major depressive episodes, ADHD, and severe personality disorders can be resolved by the careful evaluation of

1. the depressive symptomatology,
2. the presence and nature of suicidality
3. the presence or absence of true manic or hypomanic episodes
4. cognitive functions
5. the quality of interpersonal relations
6. characteristics of personality disorders
7. the role of substance abuse
8. the presence or absence and type of antisocial behavior.

Adequate diagnosis facilitates optimal treatment.

Source: Kernberg, O.F. and Yeomans, F. E. (draft): Bi-Polar Disorder,
Depression, Attention Deficit/Hyperactive Disorder and Borderline and
other Severe Personality Disorder: Practical Differential Diagnosis.