Blurring Boundaries: Differentiating Borderline Personality Disorder and Bipolar Disorder to Guide Treatment-A Case Report
Authors
Department of Psychiatry, Faculty of Medicine, Universiti Teknologi MARA Sg Buloh | Jabatan Psikiatri, Hospital Al Sultan Abdullah, Universiti Teknologi MARA (UiTM), 42300 Bandar Puncak Alam, Selangor (Malaysia)
Pusat Pakar Psikologi Jiwadamai | Faculty of Health Science National University of Malaysia (Malaysia)
Department of Psychiatry, Faculty of Medicine, Universiti Teknologi MARA Sg Buloh | Jabatan Psikiatri, Hospital Al Sultan Abdullah, Universiti Teknologi MARA (UiTM), 42300 Bandar Puncak Alam, Selangor (Malaysia)
Nur Ilyana Nasrin binti Abdul Fattah
Autism Gym Centre | Faculty of Social Science and Humanities National University of Malaysia. (Malaysia)
Article Information
DOI: 10.47772/IJRISS.2026.100601231
Subject Category: Clinical Psychology
Volume/Issue: 10/6 | Page No: 17848-17852
Publication Timeline
Submitted: 2026-06-24
Accepted: 2026-06-29
Published: 2026-07-15
Abstract
A case of a 22-year-old female with mood instability, impulsivity, recurrent self-harm, and impaired interpersonal functioning is presented. This case demonstrates the diagnostic challenges and case management due to overlapping features of Borderline Personality Disorder and Bipolar II Disorder. Impulsivity and mood instability are considered gray areas for these two conditions because of their shared symptoms and high comorbidity. The patient completed ten sessions of individual Dialectical Behavior Therapy (DBT) alongside ongoing psychiatric care. The frequency of self-injurious behaviour decreased, and improvements were observed in emotional regulation and interpersonal functioning. This case demonstrates the need for careful differential diagnosis in managing the complex affective and personality presentations.
Keywords
Borderline Personality Disorder, Bipolar Disorder, Differential diagnosis, Diagnostic challenges, Treatment implications
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References
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