Infections of Central Nervous System

Section one: SurveySection one: Survey

Ⅰ.concept : all kinds of pathogens of organisms intrude into cerebral parenchyma,

cerebral membrane, vasculature et.al ,causing acute or chronic disease of inflammation .

Ⅱ.pathogen virus 、 bacteria 、 spirochet 、 worms 、rickettsia 、 prion.

Ⅲ Ⅲ Infection’siteInfection’site

1.parenchyma: encephalitis , myelitis

encephalomyelitis.

2.meninges: meningitis, pachymeningitis.

3.both of parenchyma and meninges :

meningoencephalitis.

Ⅳ Ⅳ Infection’s pathwayInfection’s pathway

1.infection through circulation

2.direct infection : trauma ,otitis media

3.retrograde along peripheral nerves

Section twoSection two herpes simplex virus herpes simplex virus

encephalitisencephalitisⅠ.concept:

It is inflammation of the brain parenchyma, caused by herpes simplex virus.

Ⅱ Ⅱ etiology and mechanismetiology and mechanism

1.etiology: HSV, HSV is a neurotrophic DNA virus (Ⅰ、Ⅱmold )

2. mechanism:

HSV-Ⅰ： 90 percent

1) Original onset

2) succeed onset

HSV- :Ⅱ 6 to 15 percent , neonate

Ⅲ Ⅲ pathologypathology

1 .hemorrhagic necrosis:

in bilateral temporal , frontal lobe.

2.Cowdry A inclusion:

intranuclear eosinophilic inclusion

ⅣⅣclinical manifestationclinical manifestation

1. any age and any season ,acute attack.2 .prodromic symptom 3. mental symptom 4. convulsion5. disturbance of consciousness6. focal symptom:7 .meningeal irritation

Ⅴ Ⅴ investigationinvestigation

1.EEG

2.CT or MRI

3.CSF

4.pathogen of CSF

1) antigen

2) antibody

3) HSV － DNA

Ⅵ Ⅵ diagnosisdiagnosis

1 .clinical diagnosis

1) recurrent or recent herpes infection

2) fever, headache, mental symptom

convulsion ,disturbance of consciousness ,

focal signs.

3)CSF ,EEG, CT, MRI

4)responsive to specific antivirus agent

2 definite diagnosis2 definite diagnosis

besides the above, the followings are needed

1)CSF: HSV － antigen, HSV － Ab

2)brain biopsy or pathology: Cowdry in intranuclear

3)CSF: the DNA of the HSV(PCR)

4)cerebral tissue or specimen of the CSF:HSV

5)except other viral encephalitis

Ⅶ Ⅶ differential diagnosisdifferential diagnosis

• Other viral encephalitis － pathogen

• Psychosis

• Demyelination disease

Ⅷ Ⅷ treatmenttreatment

1 、 antivirotic chemotherapy:

Acyclovir ； Cancilovir

2 、 immune therapy:

interferon 、 trans-factor 、 corticosteroids

3 、 supportive therapy:

water-electrolyte balance

infection: antibiofics

ICP: mannitol

Section threeSection three

CryptococcosisCryptococcosis

Ⅰ.definition: cryptococcosis is one of the

most commonly fungal infection of CNS, the

meningitis is caused by cryptococcus.

Ⅱ.etiology: cryptococcus

Ⅲ Ⅲ PathogenesisPathogenesis

1.cryptococcus distribution

2.infection path

3.Conditioned pathogenic bacteria

1) reduction in immune capacity of body

2) debilitating diseases ,especially immune

deficit diseases:

Ⅳ Ⅳ pathologypathology

1.meningovascular lesion

2.granuloma, nodule ,abscess

3.cryptococcus

ⅤⅤclinical manifestationclinical manifestation

1.onset: insidious subacute or acute

2.early symptom

3.main symptoms

4.mental change

5.focal neurologic deficit

6.others ： hydrocephalus

Ⅶ Ⅶ investigationinvestigation

1.CSF

2.cranium CT or MRI:

3.lung X-ray : pulmonary lesions

Ⅷ Ⅷ diagnosisdiagnosis

1.chronic and debilitating disease or general physical immune deficit disease

2.chronic or insidious course

3.mainly clinical manifestation

4.CSF: cyptococcous

Ⅵ Ⅵ differential diagnosisdifferential diagnosis

tuberculous meningitis 1)fever

2)distinctive pulmonary lesions

3)organisms in CSF

Ⅸ Ⅸ treatmenttreatment

1.Anti-fungus therapy

1)amphotericin B

2)fluconazole

3)flucytosine,5-FC

2.supportive therapy

Ⅹ Ⅹ prognosisprognosis

The patient’condition is steadily progressive

worsened.It may be fatal with a few month if

untreated . Average course of disease is 6

months.

dementiadementia

• Section one summary

• Section two Alzheimer

Summary of the dementiaSummary of the dementia

Ⅰ.concept: It is an acquired and continual

impairment of intelligence, caused by cerebral dysfunction.

Ⅱ Ⅱ classificationclassification

1.degenerative dementing disorder Alzheimer disease Pick’ disease and Frontotemporal dementia Lewy body dementia

2.nondegenerative demening disorder vascular dementia infective dementing disorder metabolic encephalopathy

Section twoSection twoAlzheimer diseaseAlzheimer disease

Ⅰ.definition:

Alzheimer’disease is identified the presence

of senile plaques and neurofibrillary tangles

in the brain and cause memorial, cognitive

and psychic impairment .

It is the most common neuro － degeneration

disease.

ⅡⅡetiology and pathogenesisetiology and pathogenesis

1、 etiology: unclear, may be relation with inheritance and environments.

2、 pathogenesis:

1) reduction in choline acetyltransferase(CHAT) and acetylcholine(ACH) in the hippocampus and neocortex.

2)cholinergicfibres of neocotex originate nucleus basolis of meynert.

ⅡⅡetiology and pathogenesisetiology and pathogenesis

3)inheritance mechanism: (1) 10 percent patients with pedigree history. (2) amyloid precursor protein, APP

presenilin 1,PS1

Presenilin 2,PS2

4) environment effect

Ⅲ Ⅲ pathologypathology

1 .Senile plaques.2.neurofibrillay tangles 3.granulovacuolar degeneration4.cerebral amyloid angiopathy.

ⅣⅣclinical manifestationclinical manifestation

1.memory impairment 2.cognitive impairment 1)language impairment 2)arithmetic impairment 3)visuospatial disorientation. 4)skill action impairment.3.psychic impairment4.Others :

Ⅴ Ⅴ investigationinvestigation

1.CSF2.MRI or CT3.PET SPET and functional MRI4.neural psychology examination

Ⅵ Ⅵ diagnosisdiagnosisprobable Alzheimer disease Diagnosisprobable Alzheimer disease Diagnosis

1.dementia defined by clinical examination

2.deficits in two or more are of cognition

3.progressive worsening of memory and other cognitive functions.

4.absence of disturbed consciousness, and accompanying abnormality in mental and behavior.

5.age of patient: over 40 year.

6.exclusion of other brain diseases

Definite diagnosisDefinite diagnosis

(Using these criteria, the correct diagnosis is achieved in more than 85 percent of patients.)

A definite diagnosis can be made only from pathologic findings.

A typical history with progressive dementia and negative findings in routine test will allow a diagnosis of probable.

Ⅶ Ⅶ differential diagnosisdifferential diagnosis

1.Pick’disease

2.Vascular dementia

Ⅷ Ⅷ treatmenttreatment

1.Tacrine

2 .aricept (donepezil)

3.Exelon, rivastigmine

4.Huperzine A