neurologic disorders
Multiple Sclerosis (MS)
Symptoms and Signs of Multiple Sclerosis
Multiple sclerosis is characterized by varied CNS deficits, with remissions and recurring exacerbations. When MS is not treated with immunomodulating medications, exacerbations average about 1 every 2 years, but frequency varies greatly. Although MS may progress and regress unpredictably, there are typical patterns of progression: Relapsing-remitting pattern:Exacerbations alternate with remissions, when partial or full recovery occurs or symptoms are stable. Remissions may last months or years. Exacerbations can occur spontaneously or can be triggered by an infection such as influenza. Relapsing forms of MS include active secondary MS (defined as a clinical relapse or new lesion seen on an MRI scan of the brain or spinal cord). Primary progressive pattern:The disease progresses gradually with no remissions, although there may be temporary plateaus during which the disease does not progress. Unlike in the relapsing-remitting pattern, there are no clear exacerbations. Secondary progressive pattern:This pattern begins with relapses alternating with remissions (relapsing-remitting pattern), followed by gradual progression of the disease. Progressive relapsing pattern:The disease progresses gradually, but progression is interrupted by sudden, clear relapses. This pattern is rare. Themost common initial symptomsof multiple sclerosis are the following: Paresthesias in one or more extremities, in the trunk, or on one side of the face Weakness or clumsiness of a leg or hand Visual disturbances (eg, partial loss of vision and pain in one eye due to retrobulbar optic neuritis, diplopia due to internuclear ophthalmoplegia, scotomas) Other common early symptoms of MS include slight stiffness or unusual fatigability of a limb, minor gait disturbances, vertigo, and mild affective disturbances; all usually indicate scattered CNS involvement and may be subtle. Most patients with MS have Overview of Voiding (eg, frequency, urgency, hesitancy, Mild cognitive symptoms are common. Apathy, poor judgment, or inattention may occur. Affective disturbances, including emotional lability, euphoria, or, most commonly, depression, are common. Depression may be reactive or partly due to cerebral lesions of MS. A few patients have seizures. Unilateral or asymmetric optic neuritis and bilateral internuclear ophthalmoplegia are typical. Central vision is affected more than peripheral vision. Optic Neuritis causes loss of vision (ranging from scotomas to blindness), eye pain during eye movement, and sometimes abnormal visual fields, a swollen optic disk, or a partial or complete afferent pupillary defect. Internuclear Ophthalmoplegia results if there is a lesion in the medial longitudinal fasciculus connecting the 3rd, 4th, and 6th nerve nuclei. During horizontal gaze, adduction of one eye is decreased, with nystagmus of the other (abducting) eye; convergence is intact. In MS, internuclear ophthalmoplegia is typically bilateral; unilateral internuclear ophthalmoplegia is often caused by ischemic stroke. Rapid, small-amplitude eye oscillations in straight-ahead (primary) gaze (pendular nystagmus) are uncommon but characteristic of MS. Vertigo is common. Intermittent unilateral facial numbness or pain (resembling Trigeminal Neuralgia ), palsy, or spasm may occur. Mild dysarthria may occur, caused by bulbar weakness, cerebellar damage, or disturbance of cortical control. Other cranial nerve deficits are unusual but may occur secondary to brain stem injury. Weakness is common. It usually reflects corticospinal tract damage in the spinal cord, affects the lower extremities preferentially, and is bilateral and spastic. Deep tendon reflexes (eg, knee and ankle jerks) are usually increased, and an extensor plantar response ( Reduced mobility increases the risk of osteoporosis. In advanced MS, cerebellar ataxia plus spasticity may be severely disabling; other cerebellar manifestations include slurred speech, scanning speech (slow enunciation with a tendency to hesitate at the beginning of a word or syllable), and Charcot triad (intention tremor, scanning speech, and nystagmus). Paresthesias and partial loss of any type of sensation are common and often localized (eg, to one or both hands or legs). Various painful sensory disturbances (eg, burning or electric shocklike pains) can occur spontaneously or in response to touch, especially if the spinal cord is affected. An example is Lhermitte sign, an electric shocklike pain that radiates down the spine or into the legs or arms when the neck is flexed. Objective sensory changes tend to be transient and difficult to demonstrate early in the disease. Involvement commonly causes bladder dysfunction (eg, urinary urgency or hesitancy, partial retention of urine, mild urinary incontinence). Constipation, erectile dysfunction in men, and genital anesthesia in women may occur. Frank urinary and fecal incontinence may occur in advanced MS. Spinal cord lesions (plaques) are a common source of neuropathic pain. Progressive myelopathy, a variant of MS, causes spinal cord motor weakness but no other deficits. 