Should this patient be treated for multiple sclerosis (MS) given their acute lacunar infarcts?

Multiple Sclerosis Treatment in the Context of Acute Lacunar Infarcts

Multiple sclerosis (MS) treatment should not be initiated in a patient with acute lacunar infarcts, as these are distinct pathological entities requiring different management approaches. 1

Understanding the Distinction Between MS and Lacunar Infarcts

Diagnostic Considerations

Lacunar infarcts are small, deep infarcts resulting from occlusion of penetrating arteries, accounting for approximately 25% of all ischemic strokes 2. They represent a manifestation of cerebrovascular disease rather than the autoimmune demyelination characteristic of MS.

Key differences to consider:

• Imaging characteristics:

  • Lacunar infarcts: Small subcortical infarcts measuring <1.5 cm in diameter on CT or MRI 1
  • MS: Multiple periventricular white matter lesions with characteristic "Dawson's fingers" appearance and potential enhancement with gadolinium

• Clinical presentation:

  • Lacunar infarcts: Sudden onset of focal neurological deficits
  • MS: Typically relapsing-remitting course with varied neurological symptoms

Diagnostic Criteria for MS

The diagnosis of MS requires evidence of:

1. Dissemination of lesions in space (multiple lesions in different CNS locations)
2. Dissemination in time (new lesions developing over time)
3. No better explanation for the clinical and investigative findings 1

Management Approach for Patients with Lacunar Infarcts

Patients with lacunar infarcts should receive standard stroke management rather than MS treatment:

1. Risk factor management:

   • Hypertension control (a major risk factor for lacunar infarcts) 3, 4
   • Diabetes management (associated with multiple lacunar infarcts) 4
   • Hyperlipidemia treatment 3
   • Smoking cessation 3

2. Antithrombotic therapy:

   • Antiplatelet therapy is typically indicated for secondary prevention 1
   • Anticoagulation may be considered in specific cases where a cardioembolic source is identified 5

3. Monitoring for recurrence:

   • Patients with multiple lacunar infarcts have higher recurrence rates (24.3% vs 7.7% in single lacunar infarcts) 4
   • More aggressive risk factor management may be needed in these cases

Why MS Treatment Would Be Inappropriate

Initiating MS treatment in a patient with lacunar infarcts would be inappropriate for several reasons:

1. Misdiagnosis risk: Treating for MS when the pathology is vascular could delay appropriate stroke management and secondary prevention

2. Medication risks: MS disease-modifying therapies like interferon beta-1a and glatiramer acetate are indicated specifically for "relapsing forms of multiple sclerosis" 6, 7, not for cerebrovascular disease

3. Potential harm: Some MS treatments could potentially worsen outcomes in stroke patients through immunomodulatory effects

Clinical Pitfalls to Avoid

1. Diagnostic confusion: Multiple lacunar infarcts can sometimes be mistaken for MS lesions on imaging. Always correlate radiological findings with clinical presentation and timing of symptom onset.

2. Overlooking dual pathology: In rare cases, a patient might have both MS and lacunar infarcts. This requires careful clinical assessment and appropriate management of both conditions.

3. Misinterpreting white matter changes: Extensive white matter hyperintensities in patients with lacunar infarcts represent small vessel disease rather than demyelination 3.

4. Ignoring stroke recurrence risk: Patients with multiple lacunar infarcts have significantly higher stroke recurrence rates and poorer functional outcomes 8, 4, requiring vigilant vascular risk factor management.

In conclusion, the presence of acute lacunar infarcts warrants a cerebrovascular disease management approach rather than MS treatment, with focus on identifying and treating vascular risk factors to prevent recurrence and improve long-term outcomes.