Degenerative And Demyelinating Diseases Of The Nervous System | Spine Health & Spinal Hygiene | Scoop.it

El Paso, TX. Chiropractor, Dr. Alexander Jimenez focuses on degenerative and demyelinating diseases of the nervous system, their symptoms, causes and treatment.

Degenerative & Demyelinating Diseases

Motor Neuron Diseases

  • Motor weakness without sensory changes
  • Amyotrophic lateral sclerosis (ALS)
  • ALS Variants
  • Primary lateral sclerosis
  • Progressive bulbar palsy
  • Inherited conditions that cause anterior horn cell degeneration
  • Werdnig-Hoffmann disease in infants
  • Kugelberg-Welander disease in children and young adults

Amyotrophic Lateral Sclerosis (ALS)

  • Affects patients 40-60 years of age
  • Damage to:
  • Anterior horn cells
  • Cranial nerve motor nuclei
  • Corticobulbar and corticospinal tracts
  • Lower motor neuron findings (atrophy, fasciculations) AND upper motor neuron findings (spasticity, hyperreflexia)
  • Survival ~three years
  • Death results from weakness of the bulbar and respiratory musculature and resultant superimposed infection

ALS Variants

  • Usually eventually evolve into typical ALS pattern
  • Primary Lateral Sclerosis
  • Upper motor neuron signs begin first, but patients do eventually have lower motor neuron signs as well
  • Survival can be ten years or longer
  • Progressive Bulbar Palsy
  • Selectively involves the head and neck musculature

Inherited Motor Neuron Conditions

Alzheimer Disease

  • Characterized by neurofibrillary tangles (aggregates of hyperphosphorylated tau protein) & beta-amyloid plaques
  • Generally occurring after age 65
  • Hereditary risk factors
  • Mutations in the beta amyloid gene
  • Epsilon 4 version of apolipoprotein

Diagnosis

  • Pathologic diagnosis is the only way to definitively diagnose the condition
  • Imaging may be able to rule out other causes of dementia
  • Functional imaging studies may be further developed to become diagnostically useful in the future
  • CSF studies examining for tau proteins and beta amyloid may become useful as diagnostic tests in the future

Amyloid Plaques & Neurofibrillary Tangles

Brain Areas Affected by Alzheimer Disease

  • Hippocampus
  • Loss of recent memory
  • Posterior temporo-parietal association area
  • Mild anomia & constructional apraxia
  • Nucleus basalis of Meynert (cholinergic neurons)
  • Changes in visual perception

Progression

  • As more and more cortical areas become involved, the patient will develop more severe cognitive deficits, however paresis, sensory loss, or visual field defects are features.

Treatment Options

  • Medications that inhibit central nervous system acetylcholinesterase
  • Donepezil
  • Galantamine
  • Rivastigmine
  • Aerobic Exercise, 30 minutes daily
  • PT/OT care to maintain activities of daily living
  • Antioxidant and anti-inflammatory therapies
  • In advanced stages, may require full time, in home care

Vascular Dementia

  • Cerebral arteriosclerosis leading to stroke
  • Patient will have documented stroke history or signs of prior stroke (spasticity, paresis, pseudobulbar palsies, aphasia)
  • May be associated with Alzheimer Disease if due to amyloid angiopathy

Frontotemporal Dementia (Pick’s Disease)

  • Familial
  • Affects the frontal and temporal lobes
  • May be seen on imaging if advanced degeneration in these areas
  • Symptoms
  • Apathy
  • Disordered behavior
  • Agitation
  • Socially inappropriate behavior
  • Impulsivity
  • Language difficulties
  • Generally no memory or spatial difficulties
  • Pathology reveals Pick bodies within the neurons
  • Results in death in 2-10 years

Pick Bodies/Cytoplasmic Inclusions

http://slideplayer.com/9467158/29/images/57/Pick+bodies+Silver+stain+Immunohistochemistry+for+Tau+protein.jpg

Treatment

  • Antidepressants
  • Sertraline
  • Citalopram
  • Discontinue medications that can cause memory impairment or confusion
  • Sedatives
  • Benzodiazepines
  • Exercise
  • Lifestyle modification
  • Behavioral modification therapy

Parkinson Disease

  • May occur at any age, but rare before age 30, and increases prevalence increases in older populations
  • Familial tendency but can also without family history
  • Can be induced by certain environmental factors
  • Exposure 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)
  • Compounds which produce excessive free radicals
  • Affects substantia nigra pars compacta
  • Dopaminergic neurons
  • On pathology, the presence of Lewy Bodies
  • Accumulation of alpha-synuclein

Lewy Bodies

https://scienceofpd.files.wordpress.com/2017/05/9-lb2.jpg

Symptoms of Parkinsonism

  • Rigidity (all planes)
  • Passive ROM
  • Active movement
  • May be of cogwheel nature due to tremor symptoms
  • Bradykinesia
  • Slowness of movement
  • Inability to initiate movement
  • Freezing
  • Resting tremor (“pill-rolling”)
  • Created by oscillation of opposing muscle groups
  • Postural defects
  • Anteriorly flexed (stooped) posture
  • Inability to compensate for perturbations, resulting in retropulsion
  • Mask-like facies
  • Mild to moderate dementia
  • Later in progression, due to lewy body accumulation

Pathology

  • Deficiency of dopamine in the striatum (caudate and putamen) of the basal ganglia
  • Dopamine normally has the effect of stimulating the direct circuit through the basal ganglia, while inhibiting the indirect pathway

Carbidopa/Levodopa

  • Most common treatment is a combination drug

  • Levodopa
  • A dopamine precursor that crosses the blood-brain barrier
  • Carbidopa
  • Dopamine decarboxylase inhibitor that does not cross the BBB
  • Amino acids will reduce effectiveness (competition) and so medication should be taken away from protein

Prolonged Treatment With Carbidopa/Levodopa

  • The patient’s capacity to store dopamine declines with medication use and therefore the improvements from the medications will last for shorter and shorter periods the longer the medication is used
  • Over time can result in proliferation of dopamine receptors
  • Peak-dose dyskinesia
  • Long term use puts stress on the liver
  • Other side effects can include nausea, hypotension and hallucinations

Other Treatment Options

  • Medications
  • Anticholinergics
  • Dopamine agonists
  • Dopanime breakdown inhibitors (Monoamine oxidase or catechol-O-methyl transferase inhibitors)
  • High dose glutathione
  • Brain balancing functional neuro-rehab exercises
  • Vibration
  • Retropulsive stimulation
  • Repeated reflex stimulation
  • Targeted CMT/OMT

Multiple System Atrophy

  • Symptoms of Parkinson Disease paired with one or more of the following:
  • Pyramidal signs (Striatonigral degeneration)
  • Autonomic dysfunction (ShyDrager syndrome)
  • Cerebellar finding (Olivopontocerebellar atrophy)
  • Generally not responsive to standard Parkinson Disease treatments

Progressive Supranuclear Palsy

  • Fast progressing degeneration involving tau proteins in many areas including the rostral midbrain
  • Symptoms usually start around ages 50-60
  • Gait difficulty
  • Significant dysarthria
  • Voluntary vertical gaze difficulty
  • Retrocollis (dystonic extension of the neck)
  • Severe dysphagia
  • Emotional lability
  • Personality changes
  • Cognitive difficulty
  • Does not respond well to standard PD treatment

Diffuse Lewy Body Disease

  • Progressive dementia
  • Severe hallucinations and possible paranoid delusions
  • Confusion
  • Parkinsonian symptoms

Multiple Sclerosis

  • Multiple white matter lesions (plaques of demyelination) in the CNS
  • Variable in size
  • Well-circumscribed
  • Visible on MRI
  • Optic nerve lesions are common
  • Peripheral nerves are not involved
  • Uncommon in children under 10, but usually presents before age 55
  • Viral infection may trigger an inappropriate immune response with antibodies to a common virus-myelin antigen
  • Infectious and immune mechanisms contribute

Types Of MS

  • Primary progressive MS (PPMS)
  • Secondary progressive MS (SPMS)
  • Relapsingremitting multiple sclerasis (RRMS)
  • Most common type
  • Can develop acutely, spontaneous appear to resolve and return
  • Eventually becomes like SPMS

Optic Nerve Involvement

  • In 40% of MS cases
  • Pain with eye movements
  • Visual field defect (central or paracentral scotoma)
  • Funduscopic examination
  • May reveal papilledema if the plaque involves the optic disk
  • May not appear unusual if plaques are behind the optic disk (retrobulbar neuritis)

Medial Longitudinal Fasciculus Involvement

  • Demyelination of the MLF results in internuclear ophthalmoplegia
  • During lateral gaze there is paresis of the medial rectus and nystagmus of the contralateral eye
  • Convergence remains normal

Other Possible MS Symptoms

  • Myelopathy
  • Spastic hemiparesis
  • Impaired sensory tracts (DC-ML)
  • Paresthesias
  • Cerebellar involvement
  • Ataxia
  • Dysarthria
  • Vestibular system involvement
  • Imbalance
  • Mild vertigo
  • Nystagmus
  • Tic douloureux (trigeminal neuralgia)
  • Lhermitte's symptom
  • Shooting or tingling sensation referred to the trunk and limbs during neck flexion
  • Fatigue
  • Hot bath often exacerbates symptoms

Differentials To Consider

  • Multiple emboli and vasculitis
  • May appear as white matter damage on MRI
  • Central nervous system sarcoidosis
  • Can produce reversible optic neuritis and other CNS signs
  • Whipple disease
  • Inflammatory lesions
  • Usual eye movements
  • Vitamin B12 deficiency
  • Dementia
  • Spasticity
  • Dorsal column
  • Meningovascular syphilis
  • Multifocal CNS damage
  • CNS Lyme disease
  • Multifocal disease

Differential Diagnosis: Diagnostic Studies

  • Blood tests can help to distinguish
  • Complete blood count
  • Antinuclear antibodies (ANA)
  • Serum test for syphilis (RPR, VDRL, etc.)
  • Fluorescent treponemal antibody test
  • Lyme titer
  • ESR
  • Angiotensin converting enzyme level (to r/o sarcoidosis)

Diagnostic Studies Of MS

  • MRI with and without contrast
  • 90% of MS cases have detectable MRI findings
  • CSF findings
  • Elevation of mononuclear white blood cells
  • Oligoclonal IgG bands
  • Increased globulin to albumin ratio
  • This is also seen in 90% of MS cases
  • Increased myelin basic protein levels

Prognosis

  • Average survival after diagnosis is ~ 15 to 20 year
  • Death is usually from superimposed infection and not due to the effects of the disease itself

Sources

Alexander G. Reeves, A. & Swenson, R. Disorders of the Nervous System. Dartmouth, 2004.
Swenson, R. Degenerative Diseases of the Nervous System. 2010.