Differential Diagnosis

The patient's presentation suggests a range of potential diagnoses. Here is a categorized differential diagnosis:

• Single Most Likely Diagnosis
  • Bipolar I Disorder: The patient's history of Major Depressive Disorder (MDD), current symptoms of restlessness, decreased need for sleep, rapid speech, distractibility, and impulsive spending (purchasing a $20,000 car and a $40,000 van) are indicative of a manic episode, which is characteristic of Bipolar I Disorder.
• Other Likely Diagnoses
  • Substance-Induced Mood Disorder: The patient's symptoms could be substance-induced, particularly if she has been using stimulants or other substances that can induce manic-like symptoms.
  • Borderline Personality Disorder: The patient's impulsivity and unstable behavior could also suggest Borderline Personality Disorder, although the primary symptoms presented are more indicative of a mood disorder.
• Do Not Miss Diagnoses
  • Neurosyphilis: Although rare, neurosyphilis can present with manic-like symptoms and should be considered, especially if the patient has a history of untreated syphilis.
  • Thyroid Storm: Hyperthyroidism can cause symptoms similar to mania, including restlessness, rapid speech, and decreased need for sleep. Thyroid function tests should be performed to rule out this condition.
• Rare Diagnoses
  • Cushing's Syndrome: This rare endocrine disorder can cause mood changes, including mania, due to excess cortisol levels.
  • Multiple Sclerosis: In rare cases, multiple sclerosis can present with psychiatric symptoms, including mania, although this would be an unusual initial presentation.

DSM-5-TR Diagnosis

Based on the information provided, the most likely DSM-5-TR diagnosis is Bipolar I Disorder, given the patient's history of MDD and current manic episode.

Pharmacological Treatment

The pharmacological treatment for Bipolar I Disorder, particularly during a manic episode, typically involves the use of mood stabilizers or antipsychotics. A common first-line treatment is Lithium or an atypical antipsychotic such as Olanzapine.

For this patient, I would prescribe Olanzapine due to its efficacy in treating manic episodes and its relatively rapid onset of action compared to Lithium. Olanzapine can be started at a dose of 10-15 mg once daily, with adjustments as needed to control symptoms.

Rationale: Olanzapine is effective for the treatment of acute manic episodes and has a relatively fast onset of action. It also has the advantage of being available in both oral and injectable forms, which can be useful in an acute setting.

Assessment of Treatment:

• Appropriateness: Olanzapine is appropriate for the treatment of manic episodes in Bipolar I Disorder.
• Cost: According to local pharmacy research, the cost of Olanzapine can vary. A 30-day supply of 10mg tablets can range from $10 to $30 for generic versions, making it a cost-effective option.
• Effectiveness: Olanzapine is effective in managing symptoms of mania.
• Safety: Common side effects include weight gain, sedation, and increased risk of diabetes and dyslipidemia. Monitoring of metabolic parameters and regular follow-up are necessary.
• Patient Adherence: The once-daily dosing of Olanzapine can improve adherence compared to medications requiring multiple daily doses.

Non-Pharmacological Treatment

Excluding psychotherapeutic modalities, a non-pharmacological treatment that would be beneficial for this patient is Electroconvulsive Therapy (ECT).

Rationale: ECT is a highly effective treatment for severe or treatment-resistant mania, particularly when rapid control of symptoms is necessary due to the patient's risk to themselves or others. It can provide quicker relief from symptoms than pharmacological treatments alone.

Assessment of ECT:

• Appropriateness: ECT is appropriate for severe mania, especially when there's a high risk of harm to self or others, or when pharmacological treatments are ineffective or not tolerated.
• Cost: The cost of ECT can vary widely depending on the location and the number of sessions required. It is generally more expensive than pharmacological treatments but can be cost-effective in terms of rapid symptom resolution and reduced need for hospitalization.
• Effectiveness: ECT is highly effective for treating severe mania.
• Safety: ECT is generally safe, with temporary side effects including confusion and memory loss. The risk of permanent cognitive impairment is low when modern ECT techniques are used.
• Patient Adherence: Since ECT is typically performed under anesthesia, patient adherence is less of an issue compared to pharmacological treatments. However, patient or family consent is required, and education about the procedure and its benefits is important.