Huntington’s DiseaseProgressive autosomal dominant neurodegenerative disorder caused by expansion of a CAG (cytosine ,adenine , guanine ) repeat coding for polyglutamine in the huntingtin protein.

Genetics Review• Chromosomes - are located in the nucleus• They provide the instructions for all the

information necessary for the living organism to grow and function  

• These instructions come in form of a complex molecule called DNA (Deoxyribonucleic Acid).

DNA- Blueprint of life• DNA comes in compact form, a twisted

ladder shaped molecule called a double helix.

• Composed of a string of nucleotides. The 4 units are adenine (A), thymine (T), cytosine (C), and guanine (G).

Genes• “Functional” regions of DNA that contain

specific instructions are called genes.

• Example would be regions of DNA that code for making proteins.

Huntingtin Protein• Cytoplasmic protein found in almost all

tissues of the body and brain

• Normal function is not well understood, yet implicated in cell membrane recycling and neuroprotection.

• Studies suggest that huntingtin protein regularly interacts with other proteins found in the brain

• The altered form of huntingtin protein leads to nerve cell death in brain.

Genetic Mechanism of HD: Unstable Trinucleotide repeat

• The gene responsible for causing HD is located in chromosome 4. The gene regulates the production of huntingtin protein.

• Huntingtin protein contains within it the amino acid glutamine (C-A-G). In people with HD, however, there is an excess number of glutamine.

• That is why HD is often referred to as a trinucleotide repeat disorder

HD = Huntingtin protein with expanded CAG (glutamine) tract

CAG repeat 10 – 35 in normal individuals More than 40 repeats in diseased patients

Proteins must be folded normally to function. Mutant expansion of CAG causes an unusual huntingtin protein which clumps together in the cell and causes neuronal cell death (in the brain only)

How much CAG expansion is too much?

• People with 10 to about 35 copies of CAG have a normal functioning form of the huntingtin protein.

• Expansion of 40 or more CAG repeats is often full penetrance and the person will develop HD.

• For people who have 36 to 39 copies of CAG, the outcome is less clear. Some will develop the symptoms of Huntington's disease and some will not.

Neuropathology of HD

• HD involve atrophy and cell death of the basal ganglia, the complex subcortical structures involved in control of motor movement, cognition and sensory pathways.

• Specifically, there is a progressive and marked degeneration of the caudate and putamen (striatum).

Neuropathology

• There are different types of neurons and neurotransmitters in the striatum, and the balanced interaction between dopamine, acetylcholine, and GABA play a vital role in regulating motor movements..

• Striatal gamma aminobutyric acid (GABA-ergic) medium spiny neurons are most vulnerable to cell death in HD..

• GABA normally has inhibitory effects on the thalamus and tells the cortex to ‘brake’ movement.

• Selective loss of these specialized cells result in decreased inhibition (i.e., increased activity) of the thalamus.

• Thalamus increases output to certain regions of the cerebral cortex. This may lead to the disorganized, excessive (hyperkinetic) movement patterns of chorea.

• As disease progresses, damage to other pathways and dopamine receptors causes a decreased stimulation to the cortex and thus rigid bradykinetic features.

Risk factor: GENETICS Altered chromosome 4

Overproduction of huntingtin protein

↓Clumping of huntingtin protein

↓Neuronal cell death in the basal ganglia

↓Imbalance of neurotransmitters in striatum (GABA)

↓Decreased inhibition of the thalamus

↓Disrupts critical interneural pathways

↓Thalamus increases output to regions of the cerebral

cortex

↓Excessive movement patterns of chorea

(Hyperkinesia)

↓Decreased stimulation to the cortex (bradykinesia)

Degeneration of Basal Ganglia

The brain of a person with HD has bigger openings due to death of nerve cells in that region

Brain Imaging studies in HD: Striatal degeneration and atrophy

• Caudate and putamen hypometabolism and volume loss begins before onset of symptoms.

• Some evidence of patchy cortical thinning are more prominent over the posterior cortical regions and proceed to the anterior cortical regions with disease progression, and more evident in the left striatum.

• Atrophy of thalamic subnuclei projecting to the prefrontal areas, substantia nigra, nuclei of hypothalamus, small regions of the hippocampus, and Purkinje cells of the cerebellum.

Clinical Features of Huntington’s Disease

• Progressive neurodegenerative disorder characterized by atrophy of the basal ganglia causing triad of cognitive, motor and psychiatric impairments. There is no cure for HD.

• Inherited autosomal dominant disorder with a 50% chance of inheriting the mutant gene from an affected parent.

• In western Europe and USA prevalence is higher at about 7-10 per 100, 000. Lower in Asian and African populations.

• Typically an adult onset disorder with a mean age onset of 35-44 years (range 2 to 80 years).

• <20% first display symptoms after age 50 and have a slower progression of the disease

• <10% of cases are juvenile HD with onset before age 20 years.

Survival after onset is 15-18 years (range 5-25 years) the average age of death is 54 years old.

Motor Abnormalities: Early/Mid HD

• Chorea – is the hallmark of the disease onset, present in most adult cases.

- Abnormal, rapid, involuntary, unpredictable movements

- appears as prominent uncontrolled jerking movements of the limbs,

trunk, face and oral motor structures.

• Motor impersistence - inability to maintain voluntary muscle contractions at a constant level.

• Motor speed and coordination, fine motor control, postural stability/balance and gait progressively worsens.

Nsg. Dx: Risk for fall r/t inability to maintain voluntary muscle contraction.

Motor Abnormalities: Later Disease

• Dystonia - Prolonged involuntary twisting movements caused by slow muscle contraction

- may be caused by lack of appropriate reciprocal inhibition to the

muscle• Bradykinesia and rigidity often increases

causing inability to move or care for oneself.• Ocular motor disturbances may be seen in

as much as 75% of individuals.

• Subgroup of adult-onset HD patients has more predominant dystonia and rigidity, and paucity of chorea throughout the course of disease sometimes referred to ‘rigid-akinetic’ subtype.

Nsg. Dx: Self Care Deficit r/t uncoordinated movement and cognitive change.

Motor Speech Impairments: Hyperkinetic Dysarthria of Speech

• Oral mechanism exam often reveals normal structure, symmetry of face, lips, tongue, jaw and palate.

• Speech tasks such as conversation, oral reading, AMRs, vowel prolongation, are very useful to detect articulatory breakdown, rate and prosody changes, phonatory-respiratory discoordination

• Choreiform movements characterized by quick, unpatterned involuntary head/neck, jaw, face, tongue, palate, pharyngeal, laryngeal, and/or thoracic and abdominal movements at rest and during movement

• Dystonia or slower waxing/waning movements or posture

Nsg. Dx: Impaired motor speech r/t quick unpatterned involuntary tongue movement.

Primary Hyperkinetic Dysarthria in HD

• Articulation: Imprecise consonants, distortions and irregular breakdowns, slow & irregular AMRs

• Phonation-Respiration: Sudden forced inhalation/exhalation, voice stoppages, transient breathiness or strained-harsh voice quality, excess pitch or loudness variation

• Resonance: Intermittent hypernasality

• Prosody: Prolonged phonemes, variable rates and stress patterns, inappropriate silences, short phrases

Dysphagia: Common and Progressive

• Hyperextension of head and trunk

• Lingual chorea and decreased ability to orally control bolus

• Rigidity of neck and/or mandible in bradykinetic subgroup

• Absent or inefficient chewing

• Intraoral retention and segmented bolus transfer

• Premature loss of control and bolus spillage into pharynx

• Swallow timing and coordination deficits

Nsg Dx: Dysphagia r/t absent or inefficient chewing

Swallowing impairments

• Delayed swallow onset with advanced disease

• Decreased pharyngeal contraction and clearance

• Laryngeal penetration and aspiration

• Unpredictable inhalation/ respiratory-swallow discoordination

• Frequent belching (especially those with chorea)

• Intra-oral sensory deficits

• ‘Tachyphagia’ or behavioral impulsivity very common thus increasing risks for choking and airway obstruction

Nsg Dx: Risk for Aspiration r/t Inspiratory-swallow discoordination

Cognitive Impairments

• Visuospatial (scanning and perceptual skills)

• Executive Function: cognitive planning and sequencing, spatial working memory, cognitive flexibility and shifting set

• Memory: slowed learning rates, impaired or delayed free recall which improves significantly with cued recall/recognition, preserved retention rates

• Language: Word finding deficits, decreased phrase length and syntactic complexity,

decreased comprehension of complex information

• Cognitive-communication impairments vary in onset and severity in early-mid disease and progresses to dementia in advanced HD

Psychiatric Symptoms

• Can occur in any stage of the disease and do not follow clear progression (or relation to CAG repeat)

• May be present before motor symptoms and mistaken for other primary psychiatric illnesses (such as schizophrenia or bipolar)

• Dysfunction of frontostriatal pathways implicated in psychiatric symptoms

Psychiatric Manifestations

• Depression • Apathy • Irritability/Outbursts• Anxiety• Impulsivity• Obsessive-compulsive disorder • Aggressive Behavior• Disinhibition• Psychosis• Suicide

Myasthenia Gravis“Descending Paralysis”

(NMJ –AI destruction of AChR)

Skeletal (voluntary) muscles disorder characterized by weakness and easy fatigability due to autoimmune destruction of the AChR inthe postsynaptic membrane of theNMJ

Progressive muscle paralysis withoutsensory loss or atrophy.

• Neuromuscular Junction (NMJ)– Components:

• Presynaptic membrane• Synaptic cleft • Postsynaptic membrane

– Presynaptic membrane contains vesicles with Acetylcholine (ACh) which are released into synaptic cleft in a calcium dependent manner

– ACh attaches to ACh receptors (AChR) on postsynaptic membrane

• Neuromuscular Junction (NMJ)– The Acetylcholine receptor (AChR) is a

sodium channel that opens when bound by ACh

• There is a partial depolarization of the postsynaptic membrane and this causes an excitatory postsynaptic potential (EPSP)

• If enough sodium channels open and a threshold potential is reached, a muscle action potential is generated in the postsynaptic membrane

Background:

• Acquired autoimmune disorder• Clinically characterized by:

– Weakness of skeletal (voluntary) muscles

– Fatigability on exertion.• First clinical description in 1672 by Thomas

Willis.

Grade Levels of MG: classification by disease severity

Grade I: Focused and specific such as Ocular Myasthenia Gravis (Weakness of the eye muscles)

Grade II a: Generalized mild weakness II b: Generalized moderate weakness

Grade III: Generalized severe weakness

Grade IV: Myasthenia Crisis a severe exacerbation of the disease

an depletion of ACh receptors at the NMJ causing severe

muscle weakness, respiratory insufficiency and SOB ,

extreme difficulty swallowing, may cause

quadriplegia or quadriparesis (incomplete paralysis).

Generalized autoimmune MG Myasthenia Gravis has several courses:

1. periodic remissions 2. A slowly progressive course 3. A rapidly progressive course 4. A fulminating course (exploding in a sudden manner)

Etiology:

Thymoma it gives an incorrect instructions to

developing immune cells, ultimately resulting in autoimmunity and the production of the AChR antibodies, setting the stage for the attack on the NMJ.

Drugs• Antibiotics

(Aminoglycosides, ciprofloxacin, ampicillin, erythromycin)

• B-blocker (propranolol)• Lithium• Magnesium SO4• Procainamide• Verapamil• Quinidine• Chloroquine• Prednisone• Timolol• Anticholinergics

• Disease without recognizable cause as of spontaneous origin.

Pathophysiology

• In MG, antibodies are directed toward the acetylcholine receptor at the neuromuscular junction of skeletal muscles

• Results in:– Decreased number of nicotinic

AChR at the motor end-plate– Reduced postsynaptic membrane

folds– Widened synaptic cleft

Etiology : Ideopathic ThymomaVirus (HSV)Autoimmune

Grade Levels of MG: Classification by Severity

Grade I: Focused and specific such as Ocular MS (weakness of the eye muscles)

Grade II a: Generalized mild weakness II b: Generalized moderate weaknessGrade III: Generalized severe weakness Grade IV: Myasthenia Crisis a severe

exacerbation of the disease and depletion of ACh receptors at the NMJ causing severe muscle weakness, respiratory insufficiency and SOB, extreme difficulty swallowing may cause quadriplegia or quadriparesis (incomplete paralysis).

Generalized autoimmune MGMyasthenia gravis has several courses:

1. Periodic remissions2. Slowly progressive course3. Rapidly progressive course4. Fulminating course (exploding in a sudden manner) Clinical presentation:Ocular muscle weakness

Orbicularis Oculi- muscle that controls eyelid movement

Reduced receptor by blocking,

degradation, damage

Reduced AChR density

Decrease binding of ACh to AChR

Diminished transmission of nerve impulses at NMJ

Decrease amplitude of AP

Failure in muscle fiber contraction

Weakness muscle(Voluntary)

IgG antibody interact AChR at the NMJ.

Masseter- jaw muscle used for chewing

Occular muscle weakness– Asymmetric

Usually affects more than one extraocular muscle and is not limited to muscles innervated by one cranial nerve

Weakness of lateral and medial recti may produce a pseudointernuclear opthalmoplegia

– Limited adduction of one eye with nystagmus of the abducting eye on attempted lateral gaze

– Ptosis caused by eyelid weakness– Diplopia is very common

Risk for Eye Infection r/t exposure of cornea

• Facial muscle weakness is almost always present

– Ptosis and bilateral facial muscle weakness

– Sclera below limbus may be exposed due to weak lower lids

Altered body image r/t changes in anatomical contour of the face & neck

• Basic physical exam findings– Muscle strength testing– Recognize patients who may

develop respiratory failure (i.e. difficult breathing)

– Sensory examination and DTR’s are normal

• Bulbar muscle weakness– Palatal muscles

• “Nasal voice”, nasal regurgitation

• Chewing may become difficult

• Severe jaw weakness may cause jaw to hang open

• Swallowing may be difficult and aspiration may occur with fluids—coughing and choking while drinking

– Neck muscles• Neck flexors affected

more than extensors• Respiratory muscle weakness

– Weakness of the intercostal muscles and the diaghram may result in CO2 retention due to hypoventilation

• May cause a neuromuscular emergency

– Weakness of pharyngeal muscles may collapse the upper airway

• Monitor negative inspiratory force, vital capacity and tidal volume

• Do NOT rely on pulse oximetry

• Arterial blood oxygenation may be normal while CO2 is retained

Ineffective breathing pattern r/t collapse of upper airway

Ineffective airway clearance r/t inability to cough

• Fluctuating weakness increased by exertion– Weakness increases during the day

and improves with rest• Extraocular muscle weakness

– Ptosis is present initially in 50% of patients and during the course of disease in 90% of patients

• Head extension and flexion weakness– Weakness may be worse in

proximal muscles

• Progression of disease– Mild to more severe over weeks to

months• Usually spreads from ocular to

facial to bulbar to truncal and limb muscles

• Often, symptoms may remain limited to EOM and eyelid muscles for years

• The disease remains ocular in 16% of patients

• Remissions– Spontaneous remissions rare– Most remissions with treatment

occur within the first three years

• Limb muscle weakness– Upper limbs more common than

lower limbs

Upper ExtremitiesDeltoidsWrist extensorsFinger extensorsTriceps > Biceps

Lower ExtremitiesHip flexors (most common) Plantar FlexorsQuadricepsHamstringsFoot dorsiflexors• Co-existing autoimmune diseases

– Hyperthyroidism• Occurs in 10-15% MG

patients– Exopthalamos

and tachycardia point to hyperthyroidism

– Weakness may not improve with treatment of MG alone in patients with co-existing hyperthyroidism

– Rheumatoid arthritis– Scleroderma

– Lupus

Work-up• Electrodiagnostic studies

– Repetitive nerve stimulation– Single fiber electromyography

(SFEMG)

– SFEMG is more sensitive than RNS in MG

Electrodiagnostic studies: Repetitive Nerve Stimulation

• Low frequency RNS (1-5Hz)– Locally available Ach becomes

depleted at all NMJs and less available for immediate release

• Results in smaller EPSP’s

• Patients w/ MG– AchR’s are reduced and during RNS

EPSP’s may not reach threshold and no action potential is generated

» Results in a decrease in the compound muscle action potential

» Any decrement over 10% is considered abnormal

» Should not test clinically normal muscle

» Proximal muscles are better tested than unaffected distal muscles

Train 1 - Decremental responseTrain 2 - Post-tetanic potentiationTrain 3 – Post-activation exhaustion

• Most common employed stimulation rate is 3Hz

• Several factors can affect RNS results– Lower temperature increases the

amplitude of the compound muscle action potential

• Many patients report clinically significant improvement in cold temperatures

– AChE inhibitors prior to testing may mask the abnormalities and should be avoided for at least 1 day prior to testing

Single-fiber electromyography

• Concentric or monopolar needle electrodes that record single motor unit potentials– Findings suggestive of NMF transmission

defect Increased jitter and normal fiber

density SFEMG can determine jitter

» Variability of the interpotential interval between two or more single muscle fibers of the same motor unit

– Generalized MG

• Abnormal extensor digiti minimi found in 87%

• Examination of a second abnormal muscle will increase sensitivity to 99%

– Occular MG• Frontalis muscle is abnormal in

almost 100%• More sensitive than EDC (60%)

Lab studies– Interleukin-2 receptors

• Increased in generalized and bulbar forms of MG

• Increase seems to correlate to progression of disease

Imaging studies– Chest x-ray

• Plain anteroposterior and lateral views may identify a thymoma as an anterior mediastinal mass

– Chest CT scan is mandatory to identify thymoma

– MRI of the brain and orbits may help to rule out other causes of cranial nerve deficits but should not be used routinely

Pharmacological testing• Edrophonium (Tensilon test)

– Patients with MG have low numbers of AChR at the NMJ

– Ach released from the motor nerve terminal is metabolized by Acetylcholine esterase

– Edrophonium is a short acting Acetylcholine Esterase Inhibitor that improves muscle weakness

– Evaluate weakness (i.e. ptosis and opthalmoplegia) before and after administration

Steps:1. 0.1ml of a 10 mg/ml edrophonium solution

is administered as a test2. If no unwanted effects are noted (i.e. sinus

bradychardia), the remainder of the drug is injected

3. Consider that Edrophonium can improve weakness in diseases other than MG such as ALS, poliomyelitis, and some peripheral neuropathies

Complications of MG• Respiratory failure• Dysphagia• Complications secondary to drug treatment

– Long term steroid use• Osteoporosis, cataracts,

hyperglycemia, HTN• Gastritis, peptic ulcer

disease• Pneumocystis carinii

Guillain-Barré Syndrome

“Ascending Paralysis “AI-Destruction-Nodes of Ranvier

Acute inflammatory demyelinating polyneuropathy (AIDP) caused by an autoimmune disorder affecting the peripheral nervous system, usually triggered by an acute infectious process characterized by ascending paralysis.

Demyelination of Nerve Fibers Negative conduction abnormalities

- Slowed axonal conduction, variable conduction blocks occur in the presence of high- but not -low frequency volleys of impulse.

Positive conduction abnormalities- Generations of ectopic impulses, spontaneous

and abnormal “crosstalk” between demyelinated axons

Immunopathogenesis

Acute autoimmune disorder There is involvement of T and B

lymphocytes –↑cytokines and cytokine receptors in serum (IL 2, soluble IL 2 receptor) and CSF (IL 6, TNF α, interferon)

Brain is unable to send messages Legs and arms are commonly affected

Etiology

75% of cases are preceded by an acute infectious process usually GI or Respiratory in origin

20-35% of cases are preceded by a Campylobacter jejuni, HV, EBV infection.

Recent: swine influenza vaccine Destruction most often occurs in segments

between the Nodes of Ranvier

Why Nodes of Ranvier are the target of attack? Neural targets are likely to be gangliosides Gangliosides are complex

glycosphingolipids that contain one or more sialic acid residue

Gangliosides are present in large quantities in human nervous tissues and in key sites: NODES OF RANVIER

Pathophysiology of GBS

Etiology Autoimmue Campylobacter jejuni Virus

EBV HV SIV

B cells are activated by newly activated Th2 cells. This produces a cell-mediated and humoral response against the pathogen.

Migration to lymph nodes, a mature, differentiated APC activate CD4 T cells that

recognize antigen from the infectious pathogen

Molecular mimicry

Antigens enter into the body by multifenestrated cells

Innate immune response results in the uptake of the pathogens by immature APC

Production of antibodies and Phagocytosis of the bacteria

Cranial Nerves and Their Functions Test

No. Name General Function

Specific Function

I Olfactory Sensory SmellII Optic Sensory VisionIII Oculomotor Motor,

ParasympatheticMotor to four of six eye muscles and upper eyelid; parasympathetic: constricts pupil; thickens lens

IV Trochlear Motor Motor to one eye muscle

V Trigeminal Sensory, Motor Sensory to cornea face and teeth; motor to muscles of mastication

VI Abducens Motor Motor to one eye muscle

VII Facial Sensory,Motor, Parasympathetic

Sensory: taste; motor to muscles of facial expression; parasympathetic to salivary and tear glands

VIII Vestibulo-cochlear

Sensory Hearing and balance

IX Glossopha-ryngeal

Sensory,Motor, Parasympathetic

Sensory: taste and touch to back of tongue; motor to pharyngeal muscles; parasympathetic to salivary glands

X Vagus Sensory,Motor, Parasympathetic

Sensory to pharynx, larynx, and viscera; motor to palate, pharynx, and larynx; parasympathetic to viscera of thorax and abdomen

XI Accessory Motor Motor to 2 neck and upper back muscles

XII Hypoglossalmotor Motor to tongue muscles

Fatigue Scale Assessment Muscle Strength Assessment

Complications Breathing difficulties Residual numbness or other sensations

Long term complications: Serious, permanent problems with sensation

and coordination, including some cases of severe disability

A relapse of Guillain-Barre syndrome Rarely, death from complications such as

respiratory distress syndrome

Nursing Diagnosis

1. Acute Pain r/t stimulation of free nerve endings 2ndary to nonsynaptic transmission of nerve axons.

2. Self care deficit r/t decrease strength and endurance.

3. Low Self–Esteem r/t disruption in how client perceive one’s own body.

4. Ineffective airway clearance r/t neuromuscular dysfunction

5. Bathing/hygiene, feeding, toileting self-care deficit related to decrease energy production.

6. Fear related to sudden onset of illness. 7. Impaired spontaneous ventilation r/t denervation

of intercostal muscles.

Diagnosis Diagnosis is made by recognizing the pattern of

rapidly evolving paralysis with areflexia. Absence of fever or other systemic symptoms

and characteristics of antecedent events.

Lymphocytes and macrophages circulate in the blood and

eventually find myelin.

Lymphocytic infiltration of spinal roots and peripheral nerves, followed by

macrophage-mediated, multifocal stripping of myelin causing axonal

damage

Defects in the propagation of electrical nerve impulses with

eventual conduction blocks

Guillain–Barré syndrome

Acute progressive ascending weakness

Sensory changes:

Paresthesia/numbness

in the hands/feet

Dull aching pains of the lower back, flank or lower legs

M. Fishers Syndrome

Cranial nerve involvement: facialdroop (VII),dysphagia (V),

Diagnostics

Lumbar PunctureIn lumbar puncture “LP” CSF is withdrawn through a needle inserted into the subarachnoid space of the spinal canal between the L3-L4 or L4-L5 lumbar vertebrae.

Measure CSF pressure determine viral or bacterial origin Increase in WBC count presence of cytokines (IL 6, TNF α,

interferon) Cx: inc. ICP → rapid decrease in pressure

within CSF around spinal cord→ brain herniation

Electromyography- Needle electrodes inserted into the muscle .- Pattern of electrical activity in the muscle

both at rest and during activity may be recorded.

- Relaxed muscles are normally electrically silent except in motor end plates.

- Abnormal spontaneous activity with denervation or inflammatory changes in the affected muscle.

- Fibrillation potentials and positive sharp waves – reflect muscle irritability.

Serum Antibody titerIgM and IgG are highest in the early course of the disease.

Diagnostic Tests Nerve conduction studies (Sensory) determining the conduction

velocity and amplitude of APs where these fibers are stimulated at one point.

Helpful in determining whether sensory symptoms arising from pathology are proximal or distal to the root of ganglia

Normal conduction: - Arms: 50-70 m/s - Legs: 40-60 m/s

TreatmentThere is no cure for Guillain-Barré Syndrome, but there are treatments available…

Plasmapharesis Immunoglobulins

Multiple Sclerosis (MS)

Multiple Sclerosis (MS) is a chronic progressive, non-contagious, degenerative disease of the CNS characterized by demyelinization of neurons.

Areas affected by MS Brain Spinal cord Optic nerves

Pathologic triad CNS inflammation Demyelination Gliosis (scarring)

History of Multiple Sclerosis

The earliest description of MS was recorded in Holland on August 4, 142. But the history of the disease really begins in the 19th century with the first clear illustrations and clinical description of the disease beginning to appear in 1838.

The first actual case was diagnosed in 1849. It was Dr. Jean-Martin Charcot who is credited for giving the first signs and symptoms of Multiple Sclerosis.

Multiple Sclerosis - Epidemiology Worldwide occurrence:1.1 – 2.5 million

cases Female: male ratio = 2:1 In Canada an estimated that 55,000-75,000

people have multiple sclerosis Affects nearly 500,000 individuals in the US Occurs most frequently between ages 25 –

35

Genetic and the Immune System

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ImmuneResponseGenes

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ImmuneResponseGenes

Factors Contributing for MSGenetic Factors

Gender: Women are 2 to 3 times more likely to get the disease.

Family history of MS: A family history increases the risk

Race: MS appears more in Caucasians than in other groups

Environmental factors Latitude: As you increase latitude, mainly

above and below 40° latitude. MS is more common. It is five times more likely in temperate and cooler climate regions.

Socioeconomic status: Least common in rural and lower class.

Migration: The age at which you may move may also be an important factor. “If you move before the age of 15, your risk is likely to that of the people in the country you move to. If you move after the age of 15, your risk stays fixed at that of the country you grew up in”.

Infection : “They believe MS is a delayed reaction to a viral infection contracted during childhood by a genetically susceptible person” (O’Connor 13). The viral infections may include shingles, chicken pox, measles, or certain herpes. An idea they also have concerns the age at which you get the infection. The older you are the higher the risk for MS.

***Remember that in warm countries, children contract viruses at a younger age.

Not Everyone with a Genetic Risk Will Develop MS – Why?

Risk is modified by Environmental factorso Sunlighto Diet (e.g., vitamin D)o Other lifetime experiences

(infections?)

Multiple Sclerosis - Causeso The exact cause of multiple sclerosis is not clearo MS patients, have a higher number of immune

cells which suggests there might be an immune response; this is suspected to be due to a virus or genetic defect

o Other causes are environmental and hereditary

How Does it work?

Demyelination of Nerve Fibers in MS Positive conduction abnormalities generations of spontaneous ectopic impulses and

abnormal “crosstalk” between demyelinated axons

Negative conduction abnormalitiesslowed axonal conduction, variable conduction

blocks occur in the presence of high- but not -low frequency volleys of impulse.

The destruction of the myelin sheath leads to impaired communication between nerve cells

Mode of Action The immune system attacks axons,

causing destruction of the myelin sheath resulting in a Conduction Block which leads to permanent loss of function.

MS is an Immune-Mediated DiseasePathophysiology

Autoimmune response results in damage and loss of fibers.

Nerves can regain myelin, but the process is not fast enough to avoid the deterioration that occurs

Astrocytes form scars where myelin formerly existed

Inflammation, loss of myelin of nerve fibers, and the scarring that follows result in reduced transmission of nerve signals within the CNS.

Type of symptoms and severity vary widely due to the location of the scar tissue and the extent of demyelination

Multiple Sclerosis Signs and Symptoms Vision impairment Lhermitte‘s sign- momentary paresthesia Difficulty in walking Weakness and exhaustion Memory loss Depression Urinary and bowel problems + Babinski’s reflex

Nursing Diagnosis1. Pain chronic r/t stimulations of free nerve

ending 2 to destructions of myelinated axons.

2. Impaired sensory perception r/t nonsynaptic 3. transmission of demyelinated axons. 4. Fatigue r/t decrease energy production5. Paralysis r/t conduction block of demyelinated

axons.6. Low self Esteem r/t change in brain

structure/function. 7. Ineffective coping r/t multiple life changes. 8. Risk for care givers role train r/t severity of

the care receiver, duration of care giving required

9. Deficient knowledge regarding condition, prognosis, complications, treatment and need r/t unfamiliarity of information resources.

Multiple Sclerosis - TypesThere are 4 major types of MS

Relapsing-remitting MS (RR-MS) Primary-progressive MS (PP-MS) Progressive-relapsing MS (PR-MS) Secondary-progressive MS (SP-MS)

Relapsing-remitting MS (RR-MS) More than 80% Defined clinical exacerbation of neurological

symptoms Followed by complete or incomplete

remission during which the person fully or partially recovers from the deficits acquired during relapse

Primary-progressive MS (PP-MS) 10 to 20% Gradual progression of the disease No overlapping relapses and remissions

Progressive-relapsing MS (PR-MS) Rare Initially presenting as PP-MS, however during

the course of the disease the individuals develop true neurologic exacerbations

Steady progression of clinical neurological damage with superimposed relapses and remissions.

Secondary Progressive MS (SP-MS) SP-MS is characterized by a steady

progression of neurological damage with or without superimposed relapses and minor remissions

Individuals with SP-MS will have experienced a period of RR-MS, which may have lasted from 2 to 40 years

Any super-imposed relapses and remissions fade over time

How Is MS Diagnosed? At least two episodes of symptoms

a) Occur at different point in timeb) Result from involvement of different areas

of the central nervous system Absence of other treatable causes for the

symptoms Results of neurological testing

DIAGNOSTIC WORKUPRadiologic studies

It is diagnosed by neurological examination and brain MRI scans

o Signs of two separate attacks with demyelination of CNS supports the diagnosis.

Magnetic Resonance Imaging (MRI)Is a noninvasive diagnostic scanning technique in which the client is placed in a magnetic field. MRI provides a better contrast between normal and abnormal tissue than the CT scan. For visualization of the brain, spine, limbs, and joints, heart, blood vessels, abdomen and pelvis.

Brain Atrophy (Shrinkage) in Untreated MS

Images acquired over the course of 7 years from a single person with untreated MS Brain atrophy is seen as the enlargement of the ventricle and sulcal spaces. In untreated MS, by year 2, up to 6% of brain volume can be lost.

Serum and CSF Analysis

Blood tests Lumbar Puncture (spinal tap)

- If MS is present, persistent elevated of CSF protein IgG (oligoclonal antibody) bands can be seen in spinal fluid which is an additional confirmatory test.

Symptom Management – Examples Pain control Management of impaired bladder and bowel

function Anti-spasmodic drugs Treatment of fatigue Splinting for contractures Counseling

CNS TUMOR

Glioma Stem cells are unspecialized immature cells that can renew themselves through cell division for long periods of time.

** A glioma is a type of tumor that start in the brain or spine. It is called a glioma because it arises from glial cells. The most common site of gliomas is the brain. Types of CNS tumor

n Intracranial n Intraspinal

Main Types of Brain Tumor Primary – tumor starts in the brain Types of Primary Tumor 1. Benign - do not contain cancer cells 2. Malignant- do contain cancer cells.

Metastatic – Tumor starts somewhere else in the body.

Cell Types and Associated Tumors of the Central Nervous System.

GLIOMAS

Classification:Astrocytomas from astrocyte, invasive, slow growing in the brain and spinal cord Glioblastoma Multiforme extremely malignant, highly vascular tumors that arise from undifferentiated astrocytomasOligodendrocytomas

Cell Type Function Associated Tumors

Astrocyte

Provides nutrition, insulation,and structural support for neurons

Astrocytoma Pilocytic astrocytoma Diffuse astrocytoma Anaplastic astrocytoma GlioblastomaOligoastrocytomaPleomorphic xanthoastrocytomaSubependymal giant-cellastrocytoma

NeuronConducts electrical signalswithin neural systems

GangliogliomaGangliocytomaCentral neurocytoma

Oligodendrocyte Provides insulation to neuronal axons to facilitate signal conduction

OligodendrogliomaOligoastrocytoma

Ependymal cell Forms lining of the ventricularSystem

Ependymoma

from oligodendroglia, avascular, encapsulated, malignant form is oligodendroblastomaEpendymoma from ependymal cells, more common in children, malignant form is called ependymoblastoma.

Grading Low-grade - Well-differentiated (benign)

with a better prognosis.

High-grade - Undifferentiated (malignant) with worst prognosis.

WHO grading system for astrocytoma GRADE 1 Least malignant and slowest to grow. If they are surgically totally removed they can be associated with long-term remission.

GRADE 2 Have more malignant cells in them, they grow faster and have the tendency to recur, often more cancerous than the first time.

GRADE 3 Malignant cells undergoing mitosis, infiltrating and may recur at a higher grade.

GRADE 4 A tumor are very malignant and are often difficult to treat, also known as Glioblastoma Multiforme, usually requires operation to take as much tumor as possible followed by radiation therapy and sometimes chemotherapy

Another Grading SystemEarlier Stages GRADE I

GRADE IIGRADE III

Advanced Stages GRADE IV

LocationSupratentorial Above the tentorium, in the cerebrum, most common in adults.

Infratentorial Below the tentorium, in the cerebellum, most common in children.  Neural stem cells are multipotent and self- renewing, have been isolated from the subventricular zone,

GLIAL PROGENITOR CELLS — self-renewing precursors capable of producing astrocytes and oligodendrocytes

INTRASPINAL TUMORSClassified according to location in relation to the dura and spinal cord

Extradural- arising from the extradural space

Intradural - originating within the neural tissue. 1. Extramedullary arising from the blood vessels, meninges or

nerve roots, forming an intradural tumor Neurofibromas (Nerve sheath tumor) grow in the nerve root that extends into the extradural space Meningiomas tumor originates from the dura matter and

arachnoid membranes

2. Intramedullary tumors arising from within the substance of the spinal cord itself Ex. Ependymomas, Astrocytomas, Glioblastomas, Oligodendrogliomas, Ganglioneuromas, Medulloblastomas, Hemangioma, Hemangioblastomas

RISK FACTOR Genetics

- Cells contain genetic material called chromosomes.

- Controls growth of the cells- When the genetic material becomes

abnormal, it can loose its ability to control its growth.

Infections Diet: Nitrate C Exposure to Chemicals: Formaldehyde Vinyl Chloride Acrylonitrile

Multi hit hypothesis Cellular telephones Exposure to high tension wires Hair dyes Head trauma 

Causes Unknown Radiation therapy

Pathophysiology INTRACRANIAL TUMOR INTRASPINAL TUMOR

Nursing Diagnosis - Ineffective breathing pattern r/t denervation

of the intercostals - Impaired tissue perfusion r/t damage of

SNS. - Impaired physical mobility r/t loss of muscle

control/function. - Altered Sensory Perception r/t

neuromuscular deficit with loss of sensory reception and transmission.

- Impaired Urinary Elimination r/t loss of nerve conduction above the level of reflex arc.

DiagnosticsBone Scan PET scan CT- guided needle biopsy Open biopsy

Parkinson’s Disease (PD)Dopamine depletion-

Substantia Nigra

Degenerative disorder resulting in dysfunction of extrapyramidal system caused by dopamine depletion which interferes with inhibition of excitatory impulses.

Extrapyramidal pathways: cerebral cortex, thalamus, cerebellum and brain stem.

Nitroglial dysfunctions produce by syndrome of abnormal movement called Parkinsonism.

Extrapyramidal Tracts: uncrossed tract of motor nerves from the brain to the anterior horn of the spinal cord. Within the brain extrapyramidal pathways comprise of various relays of motorneurons between motor areas of cerebral cortex and basal nuclie, the thalamus, the cerebellum and brain stem.

Historical PerspectiveDr. James Parkinson (1755-1828)- 1817

“involuntary tremulous motion”

“pass from a walking to a running pace”

“shaking palsy”London home

EpidemiologyAve. age of onset 60Men and women affected equally but more prevalent in malesGenetic Link—chromosomes 4Environmental Toxin (MPTP)African-Americans and Asians less likely than Caucasians to develop Parkinson’s

PathogenesisFour Theories

Oxidative damage Impaired protection (↓gluthatione, ↑reactive iron)

Environmental toxins MPTP-Methyl-phenyl tetrahydropyridine--> MAO B–> MPP--> death in nigrostriatal neurons

Genetic predisposition

Mutations in the gene for the protein alpha- synuclein located on chromosome 4

Accelerated aging

PathophysiologyImbalance of dopamine and acetylcholine Loss of 80 to 90% of dopaminergic production in the substantia nigra pars compacta. Lewy Bodies

Risk factorsAging 60 Gender: Male Race: Caucasian Genetic Exposure: toxins, free radicals

Diagnostic FeaturesFour Cardinal Signs

T- remor R igidity A kinesia and bradykinesia P ostural instability

Walking often difficult to initiate and patient may have to lean forward increasingly until

Death of dopamine cells

Striatal dopamine depletion

Reduce thalamic excitation of motor cortex

Degeneration substantia nigra pars compacta neurons

Imbalance Dopamine - AcetylcholineMechanism

T – remorR - igidityA - kinesia/ BradykinesiaP - ostural instability

they can advance. They walk with small shuffling steps, have no arm swings, and may have difficult in stopping. Some patient may walk with festinating gait example: at an increasing speed to prevent themselves from falling because of there center of gravity.

Characteristic Problems

Hypophonia-soft speechDysarthria-unclear pronunciation Festination-shuffling gaitMicrographia – small handwriting

* The combination of tremor, rigidity and bradykenisia result in small tremolous and often eligible handwriting. Patients have difficulty in writing or and hand to assume flexed posture when erect.

Hypomimia – decreased facial animationBlepharospasm – involuntary eyelid closureBlepharoclonus – fluttering of close eyelidsMyerson’s sign – tap in between eyebrows

Hoehn and Yahr Staging of Severity of Parkinson’s Disease

Stage Description

0 No clinical signs evident

I Unilateral involvement

II Bilateral involvement but no postural abnormalities

III Bilateral involvement with mild postural imbalance on examination or history of poor balance or falls; patient leads independent life

IV Bilateral involvement with postural instability; patient requires substantial help

V Severe, fully developed disease; patient restricted to bed or wheelchair

Nursing Diagnosis 1. Impaired Physical Mobility r/t increase

resistance to passive motion with generalized rythmic flexion and extension of the limbs

2. Risk for Fall r/t Loss control of movements3. Self Care Deficit r/t loss of muscle tone and

coordination 4. Impaired (verbal, written) communication r/t

loss of motor control , r/t loss of oral muscle tone control

5. Activity intolerance r/t neuromuscular impairment

6. Bathing/hygiene, dressing/grooming self-care deficit r/t neuromuscular impairment

7. Risk for aspiration related to impaired muscles of swallowing

8. Risk for falls related to impaired gait and balance.

Diagnosis

History and Physical examinationBradykinesia must be present with atleast two

of the following: limb muscle rigidity, resting tremor, or postural instability.

Diagnostics Radiologic study

No specific diagnostic available (PET) Positron Emission tomography

- Computerize tomographic technique that uses radioactive substance to examine metabolic activity of various structures.

- given by inhalation or injection. - Radioactive (FDG) Fluoro-2- deoxy-D-glucose.

HEAD TRAUMA

Neurologic Assessment Levels of consciousness Glassgow coma scale Cranial nerve assessment

Definition – Traumatic Brain Injury (TBI) - is a result of an external mechanical force to the brain that leads in a change to cognitive, physical, psychosocial functioning associated with altered state of consciousness. The impairments can be temporary or permanent.

Risks Factor FallsFirearms

Traumatic Brain Injury Primary Brain Injury

Movements of brain inside skull

Brain damage and nerve injuries result in frequent and severe

headache

Brain floating with CSF

External forces transmitted to the brain

Direct injury to brain tissue

Results from what has occurred to the brain at the time of the injury

Secondary Brain Injury Physiologic and biochemical events which

follow the primary injury

Categories of Brain Injuries Closed (Blunt) Brain Injury

Acceleration/Deceleration If a moving object hits a movable

head (e.g. head gets hit with a bat) If a moving head hits something

stationary Shaken type of movement

(E.g., when head rocks back and forth in skull).

Non-Acceleration Much more rare, referred to as a

crushing injury If a moving object hits a head that is

fixed (e.g. car falls on head while you are working under it).

Categories of Brain Injuries Open Brain Injury

Low Velocityo Skull is no longer intact, part of

skull or debris gets into the brain.

High Velocityo Bullets penetrate the skull and

goes into the brain matter.

CAUSES OF BRAIN INJURIESCoup and Countercoup InjuriesConcussion vs ContusionDiffuse Axonal InjuryEpidural HematomaSubdural HematomaIntracerebral HemorrhageCompound fracture Penetrating injury

COUP The energy of impact from a small hard object tends to dissipate at the impact site, leading to a COUP contusion

COUNTERCOUP Impact from a larger object causes less injury at the impact site, since the energy is dissipated at the beginning or end of the head motion.

Contusion

Bruising type of injury to the brain resulting to sudden loss of consciousness or coma. Contusion may occur with subdural/ extradural collection of blood, intracerebral hemorrhage.

Contusion is considered severe form of axonal injury with shearing of blood.

Concussion

Mild bruising to the cerebral tissue cause by jarring of the brain resulting in transient loss of consciousness. Concussion is considered a mild form of diffuse axonal injury

Categories of Diffuse Brain Injury

Mild Concussion (without LOC) Grade I confusion disorientation with

amnesia Grade II confusion and retrograde amnesia

(5-10 min) Grade III confusion with retrograde and

anterograde.

Immediate but transitory clinical manifestation.

CSF pressure rises, ECG, EEG changes. Confusion last for several minutes. with amnesia for events preceding the

trauma. Head pain, nervousness and not being

themselves.

(grade IV) Classic Cerebral Concussion diffuse cerebral disconnection from

brain retrograde and anterograde amnesia May experience post-concussive

syndrome

Vital signs quickly stabilized Confusion for hours to days Head pain, fatigue, nausea, inability to

concentrate and Forgetfulness, mood and affect changes

Diffuse Axonal InjuryDiffuse axonal injury is characterized by extensive generalized damage to the white matter of the brain

Strains during high-speed acceleration/deceleration produced in lateral motions of the head may cause the injury.

Categories of Diffuse Brain Injury DAI Mild (coma > 6 -24 hrs) Persistent residual cognitive, phsychologic, sensorimotor deficit

Decorticate and decerebrate posturing Experience prolonged period of stupor Permanent deficit in memory, attention,

abstraction, reasoning, problem solving, executive function, vision or perception and language

Decorticate

Decerebrate

Moderate Widespread impairment cerebral cortex, diencephalon, tearing of axons both hemispheres

Transitory decortication or decerebration Unconsciousness lasting days or weeks On awakening the person is confused and

suffer long period of post-traumatic anterograde and retrograde amnesia

Severe (LOC > week)Severe mechanical disruptions of axons in both hemisphere, diencephalon and brain stem

Immediate autonomic dysfunction that disappear in few weeks

IICP 4-6 days after injury compromised coordinated movements with

verbal and written communication, inability to learn and reason, inability to modulate behavior

Compound Fracture

Object strikes the head with great force or head strike the object forcefully temporal or occipital blow upward impact of cervical vertebrae (basilar skull fracture)

Penetrating Injury

Missile (bullets) or sharp projectile (knives, axes, screwdriver)

CENTRIPETAL APPROACH(outside to inside)

• –Scalp• –Cranium • –Epidural• –Subdural• –Subarachnoid• –Intra-parenchymal• –Intra-ventricular

Traumatic Hemorrhage: Subgaleal

Cephalohematoma-Subperiosteal Outer Table

Epidural (Extradural)-Subperiosteal Inner Table

Subdural- Epi-arachnoid Subarachnoid Parenchymal Hemorrhage Intra-ventricular

EPIDURAL HEMATOMASource of Bleeding

MENINGEAL VESSELS Arterial (high pressure) Venous (low pressure)

DURAL SINUS High flow, low pressure Diploic veins (Fx) Marrow sinusoids

EPIDURAL HEMATOMA

Trauma -> fracture & concussion Tearing/stripping of both layers from inner

table Laceration of outer periosteal layer Laceration of meningeal vessels Inner (meningeal dura) intact Blood between naked bone and dura

NORMAL arterial pressure continues to dissect

Significant trauma Fracture & concussion (l.o.c) Lucid Interval

– pt Wakes Up– 40% pts.

Delayed neurologic Sx (hrs. Later) Herniation, coma and death

SUBDURAL HEMATOMA

HEMATOMA TYPES OF INJURY

ONSET OF S/S

CLINICAL MANIFESTATION

Acute Severe Head Injury

within hours

Rapid deterioration to drowsiness, agitation, stuporous, coma, signs of brain stem compression, pupil dilation contralateral hemiparesis.

Subacute Moderate Head Injury

2 hours to weeks after

Lucid , Drowsiness, stuporous coma, Increase ICP

Chronic Mild Head Injury

weeks - months after

Dull headache, slowness in thinking, apathy, drowsiness, contralateral hemipareresis, progressive neurologic changes, aphasia, papilledema, LOC changes.

INTRACEREBRAL HEMATOMA

Usually frontal and temporal lobes May occur in hemispheric deep white matter Small blood vessels injured by shearing

forces

Acts as expanding mass, compresses tissue, and causes edema

May appear 3- 10 days after head injury

Meningitis and Encephalitis

Meningitis is an inflammation of the protective membranes covering the brain and spinal cord, known collectively as the meninges.

The inflammation may be caused byinfection with viruses, bacteria, fungus andless commonly by certain drugs.

Etiology Bacterial Fungi Parasites Rickettsia Viral

- Arboviruses, Herpes viruses, Enterovirus Retroviruses, Paramyxoviruses

Septic Meningitis: common causes

Neonates: Group B Streptococci, Escherichia coli, Listeria monocytogenes

Infants: Neisseria meningitidis, Haemophilus influenzae, Streptococcus pneumoniae

Children: N. meningitidis, S. pneumoniae Adults: S. pneumoniae, N. meningitidis,

Mycobacteria, Cryptococce

Risk Factors: Cerebral shunt Extraventricular drain

o infections with staphylococci and pseudomonas

Children younger than 5 Pregnancy Working with animals Compromised immune system

Pathophysiology:

Bacteria reach the meninges through: Bloodstream Direct contact between the meninges

through either the nasal cavity or the skin

Bacterial Meningitis

Mechanism of invasion is not completely understood

Host defense mechanisms within the CSF are often ineffective.

Bacterial proliferation stimulates a convergence of leukocytes into theCSF.

Meningeal and subarachnoid space inflammation

release of cytokines into the CSF (TNF, interleukin 1, 6)

Complications of Bacterial Meningitis (IMMEDIATE) Dehydration Pericardial Effusion Death coma loss of airway reflexes seizures cerebral edema vasomotor collapse DIC Respiraytory arrest

Complications of Bacterial Meningitis (DELAYED) Snhl Ataxia Blindness

Induce a meningeal inflammatory reaction

Fever, chills, tachycardia

Infectious agent entersBlood circulation

Meningeal vessels becomeHyperemic-Permeable

Neutrophils migrateInto SAS

Produce exudates and thickens CSF

Produce exudates and thickens CSF

Inflammation of brain

parenchyma

IICP Hydrocephalus Seizures Meningeal Irritation

Macewen’sign

HeadacheVomiting

papill-edema

+kernig’s/Brudzinki’s sign

Choroid plexus/AlteredBBB

Bilateral adrenal hemorrhage Death Seizure disorder Focal paralysis Subdural effusion Hydrocephalus Intellectual deficits

Encephalitis

‡ Inflammation of the brain parenchyma, present as diffuse and/or focal neuropsychological dysfunction most commonly a viral infection with parenchymal damage varying from mild to profound.

Etiology Arboviruses and herpes simplex virus are

the most common causes of endemic and sporadic cases of encephalitis, respectively.

Varicella, herpes zoster and Epstein-Barr virus - cause of encephalitis in uncompromised hosts. ‡

Severe and Fatal Encephalitis-Arthropodborne viruses and HSV

Viral replication

Hematogenous spread to CNS ‡ Retrograde transmission along

neuronal axon Direct invasion of the subarachnoid

space through infection in the olfactory submucosa

Vectors and Reservoirs

Humans are the reservoir for enteroviruses, mumps, measles, herpes simplex, and varicella viruses.

H. capsulatum and C. neoformans are organisms found in soil contaminated with bird droppings

Vectors and Reservoirs Cats are the definitive host for T.

gondii; they acquire the parasite from eating infected rodents or other infected meat.

Monkeys are the reservoir for simian B virus (cercopithecine herpesvirus 1).

Modes of Transmission

Enteroviruses: transmitted from person to person through ingestion of materials

contaminated by the feces of an infected person

through exposure to infectious respiratory droplets

indirectly via fomites

Some causes of encephalitis, such as Listeria sp. and T. gondii, may be acquired through consumption of contaminated food

Measles and varicella viruses are transmitted from person to person through airborne route.

Simian B disease is transmitted to humans: through monkey bites exposure of naked skin or mucous

membranes to infectious monkey saliva or monkey tissue culture

Pathogenesis: Meningeal irritation + kernig’s sign + brudzinki’s sign Nucchal rigidity (neck stiffness)

COMPLICATIONS IICP Hydrocephahus Seizures

Diagnostic Strategies Brain Abscess: CT Scan

-Ring enhancement. Surrounding area of inflammation & edema

Hydrocephalus:

Lumbar Puncture Contraindication Presence of infection on the skin or soft

tissues at the puncture site Likelihood of brain herniation

Indication for CT Puncture LP in Lumbar scan before suspected Bacterial meningitis

Immunocompromised state Hx of stroke, mass lesion, focal infection,

head trauma Seizure occurring 7 days prior Abnormal LOC Inability to answer questions or follow

commands Abnormal visual fields or paresis of gaze Focal weakness Abnormal speech

CSF ANALYSIS Opening pressure 50-200 mm H2O Lateral recumbent position and sitting

position ay increase it several fold Elevated in bacterial, TB, fungal infections Falsely elevated in tense and obese patients

or when there is marked muscle contraction