Progressive Neuromuscular Disorders Pt 1: MS & ALS Flashcards
MS: Pathophysiology
Is a chronic neurological disorder in which the nerves of the CNS (brain & spinal cord) degenerate & derives its name from the buildup of scar tissue (___) or plaques that form during ___ (destruction of myelin sheath)
sclerosis; demyelinaton
MS: Clinical manifestations
- Impaired sensation, movement, & thinking
- Numbness or weakness in limbs, partial or complete vision loss, tingling or pain, electric-shock sensations w/head movements, tremor, lack of coordination, or unsteady gait, fatigue, & dizziness
- Exact cause of MS is unknown
- Both immune processes & infectious agents have been implicated in MS pathogenesis
- Demyelination is suspected to be triggered by a viral infection, probably by EBV
- Variety of precipitating factors can precede the onset or an exacerbation of MS like infection, physical or emotional stress, pregnancy, & fatigue
Etiology, Incidence, & Prevalence
- Immune-mediated dz
- 2.3 mil worldwide have MS w/onset between 20-50 yrs
- Affects women > men
- Immune-mediated dz that affects the myelin sheath & conduction pathway of the CNS
Causes
- Immune
- Environment
- Infectious
- Genetic
Immune
- Scientists know that there’s an abn immune-mediated response that attacks the myelin coating, CNS, & nerve fibers, but are unclear what sets this in motion
Environmental
- Some evidence supporting that those closer to the equator have a stronger immune system & lower chance of development; colder climates see a higher inc rate
- Smoking inc risk
Infectious
- Exposure to viruses, bacteria, & other microbes during childhood; demyelination & inflammation occur & are a triggering factor in MS development
- Studied but no proof yet → measles, canine distemper, HSV-6, EBV, chlamydia pneumonia
Genetic
- MS is not hereditary but having a 1st deg relative sig inc risk
- Id’ing >100 gene variants
- Studying epigenetics aka lifestyle choices that turn off & on genes
- Some discounted causes - living w/a dog or small pet d/t canine distemper; allergies; heavy metal exposure; physical trauma; aspartame
4 Major types of MS
- Relapsing-remitting
- Primary progressive
- Secondary progressive
- Progressive-relapsing
?
Is characterized by frequent relapses w/partial recovery but not a return to baseline
This type is seen only in a small % of pts; progressive, cumulative sx’s & deterioration occur over several yrs
Progressive-relapsing (PRMS)
?
Involves a steady & gradual neurologic deterioration w/o remission of sx’s
Pt has progressive disability w/no acute attacks
Pts w/this type of MS tend to be between 40-60 y.o. @ dz onset
Primary progressive (PPMS)
?
Begins w/a relapsing-remitting course that later becomes steadily progressive
About 1/2 of all ppl w/RRMS develop ___ within 10 yrs
Current addn of dz-modifying rx’s as part of dz management may dec the development of ___
Secondary progressive (SPMS)
?
Is the classic picture that occurs in most cases of MS; course of dz may be mild or moderate
Sx’s develop & resolve in a few wks to mos, & pt returns to baseline
During relapsing phase, pt reports loss of function & the cont’g development of new sx’s
Relapsing-remitting
MS: Management
- No spec test & can be difficult to diagnose
- Hx, physical, & neurological exam
- No cure
Treatment
- Improving the speed of recovery from attacks
- Reducing the # of attacks
- Slowing the dz progression
- Rx’s used to treat clinical manifestations
Interferon beta-1a (AVONEX or Rebif)
An immunomodulator that modifies the course of dz & also has antiviral effects
Interferon beta-1b (Betaseron, Extavia)
- Another immunomodulator w/antiviral properties
Glatiramer acetate (Copaxone)
A synthetic protein that is similar to myelin-based protein
Mitoxantrone (Novantrone)
An anti-neoplastic anti-inflammatory agent used to resolve relapses but w/risks for leukemia & cardiotoxicity
?
The 1st Mab approved for MS that binds to WBCs to prevent further damage to the myelin (may cause PML, a viral infection of the brain)
Monitoring near status is key; PML confirmed by MRI & CSF
! Rx also causes damage to the liver; routine LFT’s & self-monitoring req’d
Natalizumab (Tysabri)
Fingolimod (Gilenya)
teriflunomide (Aubagio)
dimethyl fumarate (Tecfidera)
Are newer oral immunomodulating drugs
! May cause bradycardia, esp within the 1st 6 hrs after taking it
Common s/e’s are facial flushing & GI dist
Routine labs essential as this may cause dec in WBC, predisposing pt to infection
- Medical marijuana (cannabis) also used sometimes for sx management to help reduce pain, muscle stiffness, & spasticity
- Pts need to be counseled on use as it may impair cognitive function, cause dizziness &/or intoxication, depending on form
- Corticosteroids (e.g., methylprednisolone (SoluMedrol), dexamethasone, or prednisone), anti-inflammatory, & immune-suppressing rx’s used short-term for exacerbation or initial onset
! Is just for an acute or initial episode; then pt is maintained on prev mentioned rx’s
Medication Symptom Management: Spasticity
▴ muscle relaxers
* baclofen (Lioresal)
* tizanidine (Zanaflex)
* dantrolene sodium (Dantrium)
▴ benzodiazepines
* diazepam (Valium)
▴ Also, a potassium channel blocker may be prescribed to help walking speed & ability - dalfampridine (Ampyra)
Other Symptoms
▴ Paresthesias - anti-epileptics & anti-depressants; e.g., carbamazepine (Tegretol); amitriptyline (Elavil)
▴ Cerebellar ataxia - may use propanolol & clonazepam
▴ Fatigue may utilize amantadine HCl (Symmetrel), methylphenidate (Ritalin), modafinil (Provigil)
▴ Constipation - docusate sodium [stool softeners] (Colace)
▴ Urinary retention - bethanechol (Urecholine)
▴ Urinary incontinence - oxybutynin (Ditropan)
MS - Assessment: Recognize Cues
History
* Vision, mobility, sensory perception changes
Physical assessment/s&s
* Muscle weakness & spasticity
* Tremors
* Dysmetria
* Dysphagia
Psychosocial assessment
* Anger & frustration @ length of time to obtain dx
Lab assessment
* CSF
Other diagnostic assessment
* MRI brain
?
Is a condition in which there is improper measuring of distance in muscular acts
?
Is overreaching (overstepping)
?
Is underreaching (understepping)
Dysmetria
Hypermetria
Hypometria
Common clinical manifestations
▴ Muscle stiffness or spasms
▴ Paralysis, often in the legs
▴ Problems w/bladder, bowel, or sexual function
▴ Mental status changes - memory loss, problems concentrating, visual perception, word finding but general intellect is intact; emotions can be anger, depression, euphoria
Complications
- B/c MS affects nerves throughout body, comp’s can vary
- May be periods of worsening & have a recovery period w/some improvement
- Radicular (nerve root) pains may be present part’ly in low thoracic & abd regions
- Lhermitte’s sign is electrical shocks that shoot down the spine when head is flexed forward; commonly seen in MS but also in cervical problems like spondylosis, herniation, etc. (compression of spinal cord)
?
Refers to involuntary muscle contractions that’re very painful
1st line of treatment is exercise &/or muscle relaxants like Valium, Baclofen
Spasticity
- Bladder problems can be incontinence or urinary retention. Many pts w/MS develop a neurogenic bladder & have to self-cath
- General intellect, incl long-term memory, conversational skills, & reading comprehension, remains unchanged & intact
- Normal life expectancy if sx’s are well managed. Death usually occurs as a result of infectious complications (e.g., pna), immobility, or b/c an unrelated dz
?
Is a disorder of language
dysphasia
?
Is a disorder of speech
dysarthria
- Speech is the process of articulation & pronunciation; it involves the bulbar muscles & the physical ability to form words
- Language is the process in which thoughts & ideas become spoken; it involves the selection of words to be spoken, called semantics, & the formulation of appropriate sentences or phrases, called syntax
Sensory
▴ numbness, tingling, blurred vision
▴ vertigo, tinnitus, dec hearing
▴ chronic neuropathic pain, Lhermitte’s sign
Cerebellar
▴ nystagmus, ataxia, dysphagia
▴ scanning speech - pauses between syllables of words (form of dysarthria)
▴ seizures
Sexual dysfunction
▴ ED, dim libido
▴ difficulty w/orgasmic response, painful intercourse, dec lubrication
?
Is an intense burst of pain like an electric shock that runs down the back into the arms and legs when the neck is moved
“barber chair” sign; can be painful, but is not life-threatening
Sometimes r/t severe B12 deficiencies
Lhermitte’s sign
?
Occurs b/c of damage to the optic nerve
Interferes w/the transmission of signals between the eyes & brain
Sx’s incl blurry or reduced vision & it’s often 1 of the 1st sx’s of MS
Uhthoff’s sign (think hot)
MS - Analysis: Analyze Cues & Prioritize Hypotheses
- Impaired immunity d/t the dz & rx therapy for dz management
- Dec or impaired mobility d/t muscle spasticity, intentional tremors, &/or fatigue
- Dec visual acuity & cognition d/t dysfunctional brain neurons
Diagnostic Testing
- MRI shows presence of multiple plaques
- Electrophoresis of CSF
- Evoked potential studies
- Neuropsychological test (assess cognitive impairment)
90% of ppl w/MS have been found to have elevated amounts of an antibody protein called ___ in their CSF to a greater deg than is present in their blood serum
IgG
?
Are the electrical signals generated by the nervous system in r/t sensory stimuli
Auditory, visual, & somatosensory stimuli are used commonly for clinical studies (DELAYED in persons w/MS)
Can help define the extent of the dz; are used for clinical dx in pts w/neurologic dz
Evoked potentials
MS - Planning & Implementation: Generate Solutions & Take Action
- Managing impaired immunity
- Improving mobility - exercise will help to preserve function
- Managing dec visual acuity & cognition
MS - Care Coordination & Transition Management
- Home care management
- Self-management education
- MS affects the whole family & is often unpredictable & uncertain in terms of dz course
- Healthcare resources (e.g., National MS Society)
Amyotrophic Lateral Sclerosis (ALS)
- Lou Gehrig’s dz
- Sx’s usually develop >age 50 (40-60)
- Prevalence 3.9 per 100,000 people
- Death d/t resp failure within 3-5 y.o. sx onset
- Affects voluntary muscle control & men > women; no treatment course & considered 100% fatal
- Both upper & lower neurons degenerate & die
- Unable to function, muscles gradually weaken, atrophy, & twitch (fasciculation); progressive degeneration leads to death of cells, resulting in brain losing ability to initiate & control muscle movement
- Eventually all voluntary muscles are affected & pts are paralyzed but doesn’t impair senses or ability to think
ALS: Clinical Manifestations
- Muscle cramps or stiffness, muscle weakness, slurred speech, & difficulty swallowing
- Upper motor neuron damage assoc w/spasticity
- Lower motor neuron damage assoc w/flaccidity
Not-so-Diagnostic testing
❐ No single test can be used to dx ALS
❐ CT scan &/or MRI of neck & head to r/o other cond that can mimic ALS like spinal cord tumors, herniated discs, spondylosis, MS, etc.
❐ LP for CSF protein/cytology
❐ Ck will be elevated
❐ EMG shows fibrillations or fasciculation; US can show these in deep muscles & can lead to early dx’s
❐ Repeated muscle strength testing to look for loss
❐ Swallow evals to r/o risk for aspiration
❐ RPR for neurosyphilis
❐ ANA for general autoimmune screen
❐ TSH for hypothyroid
❐ Serum protein electrophoresis for protein disorders
❐ Rheumatoid factors
❐ ESR as a general inflammatory screen
❐ Creatine phosphokinase (CPK) for muscle injury
❐ Electrolytes for imbalances
❐ CBC’s for leukemias/plasma cell dyscrasias
❐ Anti-MAG & anti-GM1 antibodies for other neuromuscular diseases
❐ Parathormone for deficiency
❐ UA/24 hr urines for heavy metals
❐ Serum lead, acid maltase, & hexosaminidase lvls for other metabolic-neuromuscular diseases
Management - Symptomatic Treatment
▻ benzothiazole (Riluzole, Rilutek)
▻ Muscle relaxants for antispasmodics - baclofen for muscle spasms
▻ Laxatives (Miralax, MOM) for constipation
▻ Analeptics (Provigil or Doxapram) for fatigue
▻ TCAs (e.g., amitriptyline) for excessive salivation, pain, & depression
▻ Antimuscarinics, anticholinergics to help secretions
benzothiazole (Riluzole, Rilutek)
▻ Decreases the glutamate lvls, an amino acid that affects the nerves that send msgs from the brain to the muscles
S/e’s
* hepatic injury
* neutropenia
* interstitial lung dz
- Drug trials w/Gilenya (an MS drug) but not appvd for ALS
- IPLEX - under investigational new drug application; used to treat growth failure in children w/severe primary IGF-1 deficiency or w/GH gene deletion who have developed neutralizing antibodies to GH
- Treatment includes rx’s for symptomatic relief, such as baclofen for muscle cramps, laxatives & stool softeners for constipation, analeptics (CNS stimulants) for fatigue & weakness, & TCA’s for excessive salivation, pain, & depression
Nursing Care
- Maintain patent airway
- Facilitate effective communication
- Make appropriate referrals
- Assess coping & depression
- Assess swallow reflex
- Nutritional needs
- Utilize conservation measure(s)
- Address possible advance directive
Remember - the psychological effects of intact cognitive ability in the face of progressive paralysis & wasting
