What are common presentations of multiple sclerosis (MS) to the emergency department?

Common Presentations of Multiple Sclerosis to the Emergency Department

The most common presentations of multiple sclerosis (MS) to the emergency department include acute exacerbations with weakness and sensory symptoms (56.6%), gait impairment (29.5%), optic neuritis, and complications of advanced disease such as urinary tract infections. 1

Primary Neurological Presentations

Acute MS Exacerbations

• Motor symptoms: Weakness (56.6% of direct MS-related ED visits), often unilateral or affecting lower extremities 1
• Sensory disturbances: Numbness and tingling (56.6% of direct MS-related visits) 1
• Gait impairment: Difficulty walking, balance problems, ataxia (29.5% of direct MS-related visits) 1
• Visual disturbances: Optic neuritis presenting as:
  • Unilateral vision loss with pain on eye movement
  • Visual field defects
  • May be the initial presenting symptom of MS 2

Brainstem and Cerebellar Manifestations

• Internuclear ophthalmoplegia (failure of ipsilateral eye adduction with contralateral eye abduction nystagmus) 2
• Vertigo and dizziness (may be confused with peripheral vertigo) 3
• Abnormalities of gaze, saccades, and pursuit 2
• Dysarthria and dysphagia

Complications of Advanced MS

Patients with higher disability scores (EDSS ≥6) are more likely to present with medical issues indirectly related to MS rather than acute exacerbations 4:

• Urinary tract infections: Common complication in patients with bladder dysfunction 4
• Respiratory issues: Particularly in those with advanced disease and respiratory muscle weakness
• Pressure ulcers: In patients with limited mobility
• Pain syndromes: Neuropathic pain, spasticity-related pain

Atypical Presentations

Special attention should be paid to atypical presentations that may be MS but require careful differential diagnosis:

• Acute disseminated encephalomyelitis (ADEM): Can mimic MS but typically has a more rapid onset 3
• Seizures: Though less common, can occur in MS patients, particularly with cortical lesions 3
• Acute mental status changes: May occur with large, confluent T2 brain lesions 3
• Dissociative (non-epileptic) seizures: May co-exist with MS 3

Diagnostic Considerations in the Emergency Setting

When MS is suspected in the ED:

• MRI of the brain and orbits with and without contrast is the primary imaging study for initial assessment 5
• The diagnosis requires demonstration of lesions disseminated in both time and space according to the McDonald criteria 3
• CSF analysis may show oligoclonal bands, supporting the diagnosis 3
• Visual evoked potentials may help identify subclinical optic nerve involvement 2

Factors Associated with ED Utilization

Several factors are associated with increased ED utilization by MS patients:

• Evidence of brain atrophy on imaging is associated with ≥3 ED visits (OR = 3.92) 1
• Patients with mild-to-moderate MS more commonly present with acute exacerbations 4
• Patients with severe MS more frequently present with medical complications 4
• Patients on disease-modifying therapies (DMTs), particularly high-efficacy DMTs and B-cell depleting therapies, have significantly fewer ED visits 1

Clinical Pearls

• MS typically presents in young adults (20-30 years) but can occur at any age 6
• MS more commonly affects women (female to male ratio of nearly 3:1) 6
• Many MS patients seeking ED care are underinsured and have high levels of disability 4
• The acute care needs of MS patients evolve over the disease course, with different resources required across the spectrum of MS severity 4

Understanding these common presentations can help emergency physicians promptly recognize and appropriately manage MS-related emergencies, potentially improving outcomes and reducing unnecessary hospitalizations.