Parkinson's Etiology and Pathophysiology Disease of basal ganglia characterized by 

Clinical Manifestations Symptoms of the disease • Do not occur until 80% of neurons in the substantia nigra are lost

• Slowing down in the initiation and execution of movement

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Classic triad of PD

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↑ Muscle tone

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Tremor

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Tremor at rest

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Rigidity

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Bradykinesia

• Impaired postural reflexes Pathologic process of PD involves degeneration of  dopamine‐producing neurons in substantia nigra  of the midbrain Disrupts dopamine‐acetylcholine balance in basal  ganglia 

Diagnostic Studies No specific tests Diagnosis based solely on history and clinical features • Firm diagnosis can be made when at least 2 of 3 characteristics of the classic triad (tremor, rigidity, and bradykinesia) are present Ultimate confirmation of the disease is a positive response to antiparkinsonian drugs

Collaborative Care Drug therapy Aimed at correcting imbalances of neurotransmitters within the CNS Antiparkinsonian drugs either

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Enhance or release supply of DA

• Antagonize or block the effects of overactive cholinergic neurons in the striatum Nutritional therapy • Malnutrition and constipation can be serious consequences • Patients with dysphagia and bradykinesia need food that is easily chewed and swallowed • Adequate roughage

Multiple Sclerosis Etiology and Pathophysiology

Clinical Manifestations

Diagnostic Studies

Collaborative Care

• Based primarily on history, clinical manifestations, and presence of multiple lesions over time measured by MRI

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• Related to infectious, immunologic, and • Disease may not be diagnosed until long after the genetic factors onset of the first symptom

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Cerebral spinal fluid (CSF) analysis

• Treat acute exacerbations by reducing edema and inflammation at the site of demyelination

• Multiple genes confer susceptibility to multiple sclerosis (MS)

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Characterized by

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Increase In oligoclonal immunoglobulin G

• Do not affect the ultimate outcome or degree of residual neurologic impairment from exacerbation

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Possible precipitating factors include

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Chronic, progressive deterioration in some

• Contains a higher number of lymphocytes and monocytes

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Immunomodulators:

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Infection Physical injury Emotional stress Excessive fatigue Pregnancy Poor state of health

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Remissions and exacerbations in others Motor manifestations Weakness or paralysis of limbs, trunk, and head Diplopia Scanning speech Spasticity of muscles

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Interferon b-1b (Betaseron) Interferon b-1a (Avonex, Rebif) Glatiramer (Copaxone) Mitoxaantrone (Novantrone) Antispasmodics CNS stimulants

Decreased libido

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Anticholinergics

Sensory manifestations

• Tricyclic antidepressants and antiseizure drugs

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Cause is unknown

• Vague symptoms occur intermittently over months and years

• Characterized by chronic inflammation, • demyelination, and gliosis in the CNS • Primary neuropathologic condition is an autoimmune disease orchestrated by • autoreactive T cells • • • •

Numbness and tingling Blurred vision Vertigo and tinnitus

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Decreased Hearing

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Chronic neuropathic pain Cerebellar manifestations Nystagmus Ataxia Dysarthria Dysphagia

Corticosteroids

• Physical therapy • Relieve spasticity • Improve coordination • Train patient to substitute unaffected muscles for impaired muscles

Myasthenia Gravis Etiology and Pathophysiology

Clinical Manifestations

• An autoimmune disease of the neuromuscular junction in which antibodies attach Ach receptors which • prevents Ach molecules from attaching and stimulating muscle contraction

Characterized by

Diagnostic Studies •

History and physical examination

• EMG (electromyogram) may show decrementing • Fluctuating weakness of skeletal muscle, strength response of electrical activity to repeated stimulation of is usually restored after rest the hand muscles

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• Muscles involved include the eyes and eyelids, chewing, swallowing, speaking, and breathing which are strongest in the AM and are exhausted with cont. activity

• Tensilon test in a patient with MG reveals improved muscle contractility after IV injection of Tensilon

Myasthenic crisis

• Cholinergic crisis occurs when there is an overdose of anticholinesterase drug and Tensilon does not improve muscle weakness. Atropine counteracts the effects of Tensilon

Collaborative Care • Drug therapy includes anticholinesterase drugs, alterate day corticosteroids and immunosuppressants • A thymectomy is a surgical therapy to remove the thymus gland because in an MG patient the thymus enhances the production of AChR antibodies

• Acute exacerbation of muscle weakness triggered by infection, surgery, emotional distress, drug overdose, or inadequate drugs

Amyotrophic Lateral Sclerosis Etiology and Pathophysiology

Clinical Manifestations

Diagnostic Studies

• Rare progressive neurologic disorder characterized by loss of motor neurons which can lead to death within 2-6 years

• Characterized by weakness of the upper extremities, dysarthria (motor speech disorder), and dysphagia

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• Motor neurons in the brainstem and spinal cord gradually degenerate in ALS

• Muscle wasting and fasciculations result from denervation of the muscles and lack of stimulation and use

• Riluzole (Rilutek) slows the progression of ALS by decreasing the amount of glutamate (excitatory neurotransmitters) in the brain

• Because dead motor neurons cannot produce or transport vital signals to • Death usually results from respiratory infection muscles, electrical and chemical messages secondary to compromised respiratory function in the brain do not reach the muscles to activate them •

Patient remains cognitively intact while wasting away

No cure for ALS

Collaborative Care • Guide patient in use of moderate intensity, endurance type exercises of the trunk and limbs • Support the patient’s cognitive and emotional functions

Huntington’s Etiology and Pathophysiology • Genetically transmitted, autosomal dominant disorder that affects both men and women of all races • Offspring of a person with this disease have a 50% risk of inheriting it •

1/10,0000 incidence in the US

• Family hx and clinical symptoms and testing for the presence of the gene can diagnosis this disease

Clinical Manifestations • Because of the excess of DA the opposite effect of parkinson’s is true

Diagnostic Studies • Antipsychotic medication, antidepressants, and antichorea drugs are prescribed

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No cure but palliative care is necessary

• Caloric requirements are higher requiring as many as 4000-5000 cal/day due to the choreic movements

• Abnormal and excessive involuntary movements (chorea), writhing, twisting movements of the face, limbs, and body • Aspiration and malnutrition along with gait deterioration •

Collaborative Care

Deterioration of mental function

• Like PD the patho involves the basal ganglia and the extrapyramidal motor system but HD involves a deficiency of the neurotransmitters Ach and GABA

Trigeminal Neuralgia Etiology and Pathophysiology • Tic Douloureux is a relatively uncommon cranial nerve disorder but it is the most commonly diagnosed neuralgic condition

Clinical Manifestations • Characterized by excruciating pain in the lips, upper or lower gums, cheek, forehead, or side of nose

Diagnostic Studies • CT scan can rule out any lesions or vascular abnormalities

Collaborative Care • Reducing recurrent episodes by being aware of triggering events

• Goal of treatment is pain relief through antiseizure • It is the 5th cranial nerve that has motor • Intense pain, twitching, grimacing, and frequent drugs Tegretol and Dilantin which may prevent an acute and sensory branches blinking can occur during an attack which is usually brief attack or promote a remission of symptoms

• Food should be high in protein and easy to chew

• Patho not fully known but might be compression of blood vessels which leads to chronic irritation of the trigeminal nerve and increased sensory firing

• Care proved to check the oral cavity after meals to remove food particles, encourage dental visits, protect against extremes of temperatures, and encourage patient to chew on the unaffected side

• Tiggering mechanism of light stimulation along the • Nerve blocking result in complete anesthesia of the distribution of the nerve with chewing, toothbrushing, hot area which can last from 6-18 months or cold blast of air on the face, yawing or even talking • Radiofrequency rhizotomy destroys the trigeminal rootlets by means of radiofrequency current • Microvascular decompression displaces blood vessels that appear to be compressing the nerve at the root entry • Gamma knife radiosurgery is a technique that uses high doses of radiation

Bell's Palsy Etiology and Pathophysiology

Clinical Manifestations

Diagnostic Studies

Collaborative Care

• Peripheral facial paralysis characterized • Flaccidity of the affected side of the face with by a disruption of the motor branches of drooping of the mouth accompanid by drooling the facial nerve CN VII

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No definitive test

• Chew on the unaffected side and provide good oral hygiene

• Evidence that reactivated herpes simplex virus may be involved due to inflammation, edema, ischemia, and eventual demyelination of the nerve

• An inability to close the eyelid, with an upward movemetn of the eyeball when closer is attempted

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Indicated by observation

• Eye shield can be used at night to retain moisture and provide protection

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• Inability to smile, frown, or whistle and possible overflow of tearing

• Treatment includes moist heat, gentle massage, stimulation may maintain muscle tone and prevent atrophy

Benign with full recovery in 6 months

• Accompanied by an outbreak of herpes vesicles in or around the ear

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Corticosteroids before paralysis is complete

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Mild analgesic Antiviral like Zovirax, Valtrex

Guillain-Barré Etiology and Pathophysiology • Acute, rapidly progressing, and potentially fatal form of polyneuritis

Clinical Manifestations • Characterized by weakness of the lower extremities, paresthesia (numbness and tingling) and paralysis can follow in the extremities

• Affects the peripheral nervous system and results in loss of myelin and edema and inflammation of the affected nerve which slows down or stops the transmission of nerve impulses

• Hypotonia (reduced muscle tone) and areflexia (lack of reflexes) are common

• Syndrome is preceded by immune system stimulation from a viral infection, trauma, surgery, HIV viral immunizations

• Facial weakness, extraoculare eye movement, dysphagia, and paresthesia of the face • •

Pain may arise Most serious complication is respiratory failure

Diagnostic Studies

Collaborative Care

• History and physical and CSF with low protein can indicate this syndrome

• Management is aimed at supportive care  especially ventilator support

IV administration of high‐dose immunoglobulin,  Sandoglobulin, can be effective

• Plasmapheresis is a blood purification  procedure used to treat GB if given within  the first 2 weeks.   Plasmapheresis is used to  remove antibodies from the bloodstream,  thereby preventing them from attacking  their targets Monitor nutritional intake as client may experience  difficulty swallowing that can lead to sever  dysphagia

Botulism Etiology and Pathophysiology

Clinical Manifestations

Diagnostic Studies

Collaborative Care

• Botulism is the most serious type of food poisoning by GI absorption of neurotoxin called Clostridium botulinum

• Symptoms consist of N/V/D and abdominal cramping about 12-24 hours after food consumption of contaminated food

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• It can grow in food contaminated with spores and it is thought that the neurotoxin destoys or inhibits the neurotransmission of acetylcholine at the myoneural junction, resulting in disturbed muscle innervation.

• Neurologic manifestaations can develop rapidy and include descending flaccid paralysis with intact sensation, photophobia, ptosis, paralysis of extraocular muscles, blurred vision, diplopia, dry mouth, sore throat and difficulty swallowing

• Initial treatment of IV botulinum antitoxis is given but an intradermal test dose for sensitivity to horse serum is given prior to the antitoxin

• Bacteria can be destroyed by boiling for 10 minutes but high temperature pressure cooking is the only safe method for home canning

• Magnesium is contraindicated because it worsens toxin-induced neuromuscular blockade so non-mag containing laxitives and high colonic enemas and gastric lavage are given to decrease absorption of the toxin

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Blood and CSF rule out other diseases

• Primary prevention is the goal to management.

Cans with swelling should never be used

Tetanus Etiology and Pathophysiology

Clinical Manifestations

• Tetanus (lockjaw) is an extremely • Spore enters through a traumatic wound that provides severe polyradiculitis and polyneuritis low oxygen environment for the organism to mature affecting spinal and cranial nerves • The toxin interferes with the function of the reflex arc by blocking inhibitory • Symptoms frequently occur after wound has healed transmitters at the presynaptic sits in the spinal cord and brainstem • Found in soil, garden mold, and manure and can be found with dental infections, chronic otitis media, injections of heroin, human and animal bites, burns, frostbite, open fractures, and gun shot wounds

• manifestations include stiffness in the jaw (trismus) and neck, fever, and other symptoms of general infection, the neck muscles back, abdomen, and extremities become rigid. •

Seizures can occur and can be very painful

Diagnostic Studies

Collaborative Care

• Administration of a tetanus and diphtheria toxoid (Td) • Tetanus booster should be given every 10 booster and tetanus immune globulin (TIG) before the years but if an open wound occurs it should be onset of symptoms given before 5 years •

Valuim can also be given to control spasms

• Avoid tirggering seizures by placing patient in a quiet dark room

• Tracheostomy and mechanical ventilation may be needed