Infections of Central
Nervous System
Section 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 Infection’site
1.parenchyma: encephalitis , myelitis
encephalomyelitis.
2.meninges: meningitis, pachymeningitis.
3.both of parenchyma and meninges :
meningoencephalitis.
Ⅳ Infection’s pathway
1.infection through circulation
2.direct infection : trauma ,otitis media
3.retrograde along peripheral nerves
Section two
herpes simplex virus
encephalitis
Ⅰ.concept:
It is inflammation of the brain
parenchyma, caused by herpes
simplex virus.
Ⅱ etiology 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 pathology
1 .hemorrhagic necrosis:
in bilateral temporal , frontal lobe.
2.Cowdry A inclusion:
intranuclear eosinophilic inclusion
Ⅳclinical manifestation
1. any age and any season ,acute attack.
2 .prodromic symptom
3. mental symptom
4. convulsion
5. disturbance of consciousness
6. focal symptom:
7 .meningeal irritation
Ⅴ investigation
1.EEG
2.CT or MRI
3.CSF
4.pathogen of CSF
1) antigen
2) antibody
3) HSV－DNA
Ⅵ diagnosis
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 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 differential diagnosis
• Other viral encephalitis－pathogen
• Psychosis
• Demyelination disease
Ⅷ treatment
1 、antivirotic chemotherapy:
Acyclovir ； Cancilovir
2 、immune therapy:
interferon 、 trans-factor、 corticosteroids
3、supportive therapy:
water-electrolyte balance
infection: antibiofics
ICP: mannitol
Section three
Cryptococcosis
Ⅰ.definition: cryptococcosis is one of the
most commonly fungal infection of CNS, the
meningitis is caused by cryptococcus.
Ⅱ.etiology: cryptococcus
Ⅲ Pathogenesis
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 pathology
1.meningovascular lesion
2.granuloma, nodule ,abscess
3.cryptococcus
Ⅴclinical manifestation
1.onset: insidious subacute or acute
2.early symptom
3.main symptoms
4.mental change
5.focal neurologic deficit
6.others ：hydrocephalus
Ⅶ investigation
1.CSF
2.cranium CT or MRI:
3.lung X-ray : pulmonary lesions
Ⅷ diagnosis
1.chronic and debilitating disease or general
physical immune deficit disease
2.chronic or insidious course
3.mainly clinical manifestation
4.CSF: cyptococcous
Ⅵ differential diagnosis
tuberculous meningitis
1)fever
2)distinctive pulmonary lesions
3)organisms in CSF
Ⅸ treatment
1.Anti-fungus therapy
1)amphotericin B
2)fluconazole
3)flucytosine,5-FC
2.supportive therapy
Ⅹ prognosis
The patient’condition is steadily
progressive
worsened.It may be fatal with a few month if
untreated . Average course of disease is
6
months.
dementia
• Section one summary
• Section two Alzheimer
Summary of the dementia
Ⅰ.concept:
It is an acquired and continual
impairment of intelligence, caused by
cerebral dysfunction.
Ⅱ classification
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 two
Alzheimer 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
Ⅱetiology 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.
Ⅱetiology 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 pathology
1 .Senile plaques.
2.neurofibrillay tangles
3.granulovacuolar degeneration
4.cerebral amyloid angiopathy.
Ⅳclinical manifestation
1.memory impairment
2.cognitive impairment
1)language impairment
2)arithmetic impairment
3)visuospatial disorientation.
4)skill action impairment.
3.psychic impairment
4.Others :
Ⅴ investigation
1.CSF
2.MRI or CT
3.PET SPET and functional MRI
4.neural psychology examination
Ⅵ diagnosis
probable 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 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 differential diagnosis
1.Pick’disease
2.Vascular dementia
Ⅷ treatment
1.Tacrine
2 .aricept (donepezil)
3.Exelon, rivastigmine
4.Huperzine A