[Differential diagnosis between borderline personality disorder and bipolar disorder]

The relationship between bipolar disorder and borderline personality disorder remains controversial since in both conditions there are overlapping and similar symptomatic dimensions. Symptomatic dimensions suitable to subserve differential diagnosis are: mood, mood variability mode, and personal and family history. Characteristics of psychotic symptoms may also be useful in the differentiation. On the other hand, anxiety symptoms, neuropsychological profiles, neuro-imaging procedures and biomarkers seem not to contribute to differentiate between both diseases. The presentation of nonsuicidal self mutilation behavior can offer some differences between bipolar and borderline personality disorders, but both can coexist in clinical comorbid forms and do not significantly contribute to the differential diagnosis. Differential diagnosis is complicated by the fact that a low percentage of patients can experience comorbidity of both conditions. In this work we review all these issues, and particularly emphasize the importance of sitematically take into account the patient background, the course that follows his or her disorder, together with the outcome in response to medical decisions.