Signs and Symptoms of Multiple Sclerosis
Multiple sclerosis typically presents in young adults (ages 20-30 years) with unilateral optic neuritis, partial myelitis, sensory disturbances, or brainstem syndromes such as internuclear ophthalmoplegia developing over several days. 1
Primary Neurological Manifestations
The clinical presentation varies significantly between patients but follows recognizable patterns 2:
Common Presenting Symptoms
- Visual disturbances: Unilateral optic neuritis is a classic initial presentation, causing vision loss, eye pain with movement, and color desaturation 1
- Sensory abnormalities: Numbness, tingling, or paresthesias in limbs or trunk 2, 1
- Motor weakness: Limb weakness affecting one or more extremities, often asymmetric 1, 3
- Brainstem syndromes: Internuclear ophthalmoplegia, diplopia, dysarthria 2, 1
- Spinal cord involvement: Partial myelitis causing weakness, sensory level, or bladder dysfunction 1
- Balance and coordination problems: Ataxia and gait disturbances 3
Additional Common Symptoms
- Fatigue: One of the most disabling symptoms, often disproportionate to physical findings 3
- Cognitive impairment: Memory problems, decreased processing speed, executive dysfunction 1, 3
- Bladder and bowel dysfunction: Urgency, frequency, retention, or incontinence 3
- Sexual dysfunction: Erectile dysfunction, decreased libido, anorgasmia 3
- Neuropathic pain: Burning, shooting, or stabbing pain 3
- Spasticity: Muscle stiffness and spasms 3
Less Common Symptoms
- Dysarthria and dysphagia: Speech and swallowing difficulties 3
- Vertigo: Spinning sensation or dizziness 3
- Tremors: Action or intention tremors 3
Rare Manifestations
- Seizures: Occur in a small minority of patients 3
- Hearing loss: Particularly bilateral sudden hearing loss should prompt evaluation for alternative diagnoses 2
Clinical Course Patterns
Relapsing-Remitting MS (Most Common)
The relapsing-remitting pattern is the most common initial presentation, characterized by acute onset of neurological symptoms developing over hours to days, with episodes typically stabilizing and resolving spontaneously. 4 This accounts for approximately 85% of initial presentations 5.
Primary Progressive MS
Primary progressive MS presents differently, with steadily increasing neurological disability from onset, often presenting as progressive myelopathy, and no distinct relapses or remissions. 4
Temporal Characteristics
- Symptom onset: Develops over hours to days (not sudden) 4, 1
- Episode duration: Symptoms must last at least 24 hours to qualify as a true relapse 4
- Age of onset: Typically between 10-59 years, with peak onset at 20-30 years 2, 1
Red Flags Suggesting Alternative Diagnoses
Sudden onset of focal neurologic symptoms such as headache, confusion, diplopia, dysarthria, focal weakness, or numbness may indicate stroke rather than MS. 2 Other atypical features requiring additional investigation include 2, 4:
- Dementia as a presenting feature
- Epilepsy at onset
- Aphasia
- Bilateral sudden hearing loss
- Age of onset under 11 or over 50 years (requires more stringent diagnostic criteria)
Diagnostic Requirements
MS diagnosis requires evidence of central nervous system lesions disseminated in both time and space, and diagnosis should not be made solely on the basis of MRI results, as at least one clinical event consistent with acute demyelination remains the cornerstone. 2, 4
Key Diagnostic Tools
- MRI: Preferred imaging showing characteristic T2 lesions in periventricular, juxtacortical, infratentorial, and spinal cord regions, with lesions typically having sharp edges, ovoid shape, and orientation perpendicular to ventricles 4
- Cerebrospinal fluid analysis: Oligoclonal bands specific to CSF are often present 4, 1
- Visual evoked potentials: May help secure diagnosis in atypical presentations 2
Management Overview
Disease-Modifying Therapies
Nine classes of disease-modifying therapies are available for relapsing-remitting MS, with efficacy rates ranging from 29%-68% reduction in annualized relapse rates compared with placebo or active comparators. 1 These include interferons, glatiramer acetate, teriflunomide, sphingosine 1-phosphate receptor modulators (such as fingolimod), fumarates, cladribine, and monoclonal antibodies 1, 6.
Symptomatic Management
Treatment addresses primary symptoms (directly from demyelination), secondary symptoms (complications of primary symptoms like urinary tract infections), and tertiary symptoms (psychosocial consequences like depression) 3. This includes:
- Physical therapy and rehabilitation for motor symptoms 2, 3
- Occupational therapy for functional limitations 2
- Cognitive rehabilitation for cognitive impairment 2
- Pharmacologic management of specific symptoms (spasticity, pain, bladder dysfunction) 3, 7
Monitoring
Regular MRI monitoring is recommended to assess disease activity and treatment response. 2 The goal is early initiation of disease-modifying drugs to reduce relapses, brain lesions, and disability progression 1, 5.
Important Caveats
Diagnosis should be made by a specialist familiar with MS, its differential diagnoses, and interpretation of paraclinical assessments. 2 Key differential diagnoses include cerebrovascular disease, infectious diseases (HTLV1, Lyme disease), neuromyelitis optica spectrum disorder, paraneoplastic disorders, and genetic disorders of myelin 2, 4.