Clinical features:
Wide spectrum of signs, symptoms and course - depends on the location and severity of the pathological lesion(s). Typically, a young adult that trips or legs feel heavy. Most follow an initial variable relapsing and remitting course, usually with full recovery --> later remissions do not lead to full recovery.
Presenting features:
Onset in 85-90% is single symptom (depends on location of demyelination), but on careful history, there is usually a variable period of easy fatigue and low energy – optic neuritis (in 20%; usually starts as pain in eye, double vision or blurred vision; may get loss of visual acuity in one eye); diplopia (from involvement of 4th or 6th cranial nerve); sensory disturbance of the limbs (especially proprioception, parathesia, numbness or ‘leg feels heavy’; numbness may start in foot); weakness in one arm or leg (monoparesis); or weakness of both legs (paraparesis); ataxia (especially uncharacteristic tripping and incoordination of limbs – indicates cerebellar lesion); Lhermitte’s sign (sudden electric shock like sensation shooting down spine into arms or legs when patient flexes neck - thought to indicate posterior column plaques); urinary urgency and incontinence (from spinal cord involvement); severe fatigue (common disabling symptom).
Diagnosis is a generally a clinical one – confidence in diagnosis is often described as definite, probable or possible. No specific laboratory test – spinal fluid abnormalities may show autoimmune abnormalities. Evoked potentials (measure of conduction through CNS) show slowed conduction in areas of demyelination. MRI scan is sensitive in showing typical lesions and can show evidence of dissemination of lesions in both time and space.
Differential diagnosis – SLE; polyarteritis nodosa; Sjogrens syndrome; Behcet’s disease; Lyme disease; HIV; sarcoidosis; Vitamin B12 deficiency; spinocerebellar disorder; encephalomyelitis; leukodystrophies; multifocal leuckoencephalopathy
Features of established multiple sclerosis:
• motor and sensory – spinal cord involvement --> lower limb symptoms are common (heaviness, weakness, stiffness, gait problems, failure of limb to respond to ‘commands’); strength is decreased, tone increased, reflexes exaggerated (hyperreflexia), clonus, positive Babinski’s reflex, sensory loss, Lhermittes’ sign, proprioception deficits
• optic – optic neuritis (40%) --> blurring or darkening of vision, decreased colour perception, pain on eye movement; isolated cases of optic neuritis may be a forme fruste of MS
• cerebellar and brainstem (50%) – action/intention tremor, cerebellar gait disorder, dysarthric (syllabic) speech, diplopia, nystagmus, trigeminal neuralgia, hearing loss, olfactory abnormalities
• genitourinary – urinary retention, urgency, frequency, stress or overflow incontinence, sexual problems
• cognitive and emotional – in up to 50% - subcortical dementia, memory lapses, apraxia, aphasia, changed executive function, depression
• pain – in up to 50%; neurogenic in origin; dysaethetic limb pain is most common – usually burning in nature and may be due to spinal cord involvement
• fatigue – more common during attacks of MS; cause of fatigue is unknown; very disabling symptom
• impaired mobility from lower limb muscle weakness and spasticity (can be painful)
• a number of complications develop secondarily to the neurological dysfunction (eg infections, depression, contractures (from spasticity), pressure sores)
Symptoms can be aggravated by slight rise in temperature (eg fever, bathing, exercise, environmental) – even as little as 0.5 degree.
Involvement of the foot:
Cold feet are common (may only be the patients perception or may actually feel cold); weakness (foot drop); sensory symptoms; ankle oedema
Gait analysis (Gehlsen et al, 1986) has shown that those with MS have a shorter stride length, slower walking rates, higher cadence than those without MS. Also found were lower excursions for knee and ankle joints with less vertical lift of centre of gravity and a greater truck lean. Walker et al (2000) showed declines in velocity and cadence parameters over an 18 month period in 18 patients with multiple sclerosis. Base of gait in those with MS appears to be wider, presumably for increased stability.
Click to expand...