What are the signs and symptoms of multiple sclerosis?

Signs and Symptoms of Multiple Sclerosis

Multiple sclerosis (MS) presents with a wide variety of signs and symptoms due to inflammatory demyelination and axonal damage in different parts of the central nervous system. The clinical manifestations depend on the location of lesions in the brain, spinal cord, and optic nerves 1.

Common Initial Presentations

• Visual disturbances:

  • Optic neuritis (20-31% of initial presentations) 2
  • Visual impairment, scotoma, red-green desaturation, pain with eye movement 2
  • May lead to optic nerve atrophy or pallor in chronic cases 2

• Motor symptoms:

  • Weakness in limbs (can be unilateral or bilateral)
  • Spasticity
  • Hyperreflexia or hyporeflexia 3

• Sensory symptoms:

  • Numbness or tingling (paresthesias)
  • Sensory disturbances developing over several days 4
  • Lhermitte's sign (electric-like sensation down the spine with neck flexion) 5

• Balance and coordination issues:

  • Ataxia
  • Impaired coordination
  • Postural control dysfunction (even early in disease course) 3
  • Gait abnormalities with reduced speed and impaired walking balance 3

• Brainstem symptoms:

  • Internuclear ophthalmoplegia
  • Facial weakness or numbness
  • Vertigo
  • Hearing loss 4

Additional Manifestations

• Bladder, bowel, and sexual dysfunction:

  • Urinary urgency, frequency, or incontinence
  • Constipation or fecal incontinence
  • Sexual dysfunction 1

• Cognitive impairment:

  • Memory problems
  • Difficulty concentrating
  • Slowed information processing 4

• Fatigue:

  • Overwhelming tiredness unrelated to physical exertion
  • Worsens with heat exposure (Uhthoff's phenomenon) 5
  • Affects 50-80% of MS patients 3

• Pain:

  • Neuropathic pain
  • Musculoskeletal pain
  • Severe and diffuse pain may precede onset of weakness 2

• Mental health issues:

  • Depression
  • Anxiety
  • Adjustment disorder
  • Bipolar disorder (less common)
  • Psychosis (rare) 6

Characteristic Patterns

• Relapsing-remitting pattern (most common):

  • Symptoms develop over days
  • Last for at least 24 hours (true exacerbation) 1
  • Followed by partial or complete recovery
  • Stable periods between episodes 4

• Progressive pattern:

  • Steadily increasing neurological disability
  • May follow relapsing course (secondary progressive)
  • May be progressive from onset (primary progressive) 4

Imaging Findings

• Brain MRI:

  • T2-hyperintense lesions (typically periventricular, juxtacortical, infratentorial) 1
  • Gadolinium-enhancing lesions (active inflammation) 2
  • Nodular or ring-enhancing lesions 2
  • Cortical lesions (may be difficult to detect on conventional MRI) 2

• Spinal cord MRI:

  • Focal lesions with clearly demarcated borders 2
  • Typically small (covering less than two vertebral segments)
  • Usually located in the periphery of the spinal cord 2
  • May show T1 hypointensity at higher field strengths 2

• Optic nerve imaging:

  • T2 hyperintensity
  • Associated optic nerve swelling
  • Contrast enhancement in acute lesions 2

Special Considerations

• Atypical presentations that require careful evaluation:

  • Isolated cranial nerve dysfunction 2
  • Pure sensory symptoms
  • Pure motor variant (without sensory signs) 2
  • Symptoms limited to specific regions (e.g., bilateral facial palsy, pharyngeal-cervical-brachial weakness) 2

• Red flags that suggest alternative diagnoses:

  • Posterior optic nerve involvement including the chiasm
  • Simultaneous bilateral optic nerve involvement
  • Long optic nerve lesion
  • Longitudinally extensive spinal cord lesions (>3 vertebral segments)
  • Leptomeningeal enhancement 2

• Fall risk:

  • Over 50% of MS patients fall at least once yearly
  • Associated with injuries and fear of falling
  • Contributes to reduced participation in activities 3

Early recognition of MS symptoms is crucial for timely diagnosis and treatment, which can help prevent long-term disability and improve quality of life 1. The diagnosis should be based on a combination of clinical presentation, MRI findings, and laboratory tests (including cerebrospinal fluid analysis when indicated) according to the 2017 McDonald criteria 1, 4.