• Clinical features:
- Headache, vomiting, & fever - Children: may also have
convulsions
- Classic findings: cervical rigidity, inability to straighten the knee following hip flexion, owing to pain (Kernig sign), & knee & hip flexion following neck flexion secondary to pain (Brudzinski sign)
- Lumbar puncture:
polymorphonuclear leukocytes, increased protein, & decreased glucose level of the CSF
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One of the physically demonstrable symptoms of meningitis is Kernig's sign. Severe stiffness of the hamstrings causes an inability to straighten the leg when the hip is flexed to 90 degrees.
One of the physically demonstrable symptoms of meningitis is
Brudzinski's sign. Severe neck stiffness causes a patient's hips and knees to flex when the neck is flexed.
B. Tuberculous meningitis(결핵수막염)
• caused by Mycobacterium
tuberculosis, is more common in people from countries where
tuberculosis is endemic, but is also encountered in persons with immune problems, such as AIDS C. Syphilitic meningitis(매독수막염)
•
Treponema pallidum
• Three severe manifestations of tertiary syphilis
a. Meningovascular syphilis b. Tabes dorsalis
c. Dementia paralytica (luetic dementia)
D. Viral meningitis(바이러스 수막염)
• Enterovirus (coxsackie B virus, echovirus)
• Arboviruses: important group responsible for many cases of meningitis and encephalitis
• Viruses infect birds and animals as well as humans and are
• Types of encephalitis
a. Western equine encephalitis b. Eastern equine encephalitis c. St. Louis encephalitis
d. California encephalitis
e. West Nile virus: a “foreign” virus from Africa, first case identified in 1999 in New York City area
2) Cryptococcal meningitis(크립토 콕쿠스 수막염) occurs most
frequently in immunocompromised persons
•
Cryptococcus neoformans
• Occurs most frequently in
immunocompromised persons
• In Africa, cryptococcal meningitis is estimated to be the most
common cause of meningitis and it accounts for 20–25% of AIDS-related deaths in Africa.
3) Amebic meningoencephalitis (아 메바수막뇌염) may be
water-borne
• A disease of the central nervous system caused by infection from
Naegleria fowleri and
Acanthamoeba.
•
Naegleria fowleri
propagates in warm, stagnant bodies offreshwater (typically during the summer months), and enters the central nervous system after
insufflation of infected water by attaching itself to the olfactory nerve
• It then migrates through the cribiform plate and into the
olfactory bulbs of the forebrain, where it multiplies itself greatly by feeding on nerve tissue.
• During this stage, occurring approximately 3–7 days post-infection, the typical symptoms are parosmia, rapidly progressing to anosmia (with resultant
ageusia) as the nerve cells of the olfactory bulbs are consumed and replaced with necrotic lesions.
Histopathology of amebic
meningoencephalitis due to Naegleria fowleri. Direct fluorescent antibody stain.
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4) Cerebral abscess (뇌 고름집) is the result of cerebritis
• Bloodborne microorganisms cerebritis (뇌염)
Brain abscess development and its complications. A cerebral abscess may cause death through the production of secondary abscesses with intraventricular rupture; alternatively, death may result from transtentorial herniation. The abscess
consists of a necrotic purulent core, a layer Cerebral abscess. A young man with
bacterial endocarditis developed an abscess in the left basal ganglia.
7. 바이러스성 뇌척수염 (Viral Encephalomyelitis)
• CNS의 실질에 바이러스 감염
1) West Nile virus(서부 나일강 열바이러스) is a recently emergent pathogen 2) Poliomyelitis (폴리오, 회색질척수염) refers to CNS infection by a
single-stranded RNA virus
3) Rabies (광견병) is a fatal infection transmitted by animal saliva 4) Herpes simplex virus (단순헤르페스바이러스 및 관련 감염) is the
most common cause of nonepidemic encephalitis
5) Arbovirus encephalitis (아르보바이러스 뇌염) are transmistted to humans by infected mosquitos or tick bites
6) Subacute Sclerosing Panencephalitis (SSPE, 아급성 경화 범뇌염) is caused by the measles virus
7) Progressive multifocal leukoencephalopathy (진행성 다초점 백색질뇌 증) most often affects immnocompromised patients
8) AIDS encephalopathy(후천성면역결핍증 뇌병증) is often a primary manifestation of HIV infection of the CNS
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1)West Nile virus is a recently emergent pathogen
• A mosquito-borne zoonotic
arbovirus belonging to the genus
• This flavivirus is found in
temperate and tropical regions of the world.
• It was first identified in the West Nile subregion in the East African nation of Uganda in 1937.
• The incubation period for WNV – the amount of time from infection to symptom onset – is typically from between 2–15 days.
• Headache can be a prominent symptom of WNV fever,
meningitis, encephalitis,
menigoencephalitis and it may or may not be present in
poliomyelytis-like syndrome thus headache is not a useful indicator of neuroinvasive disease.
• West Nile Fever (WNF), which occurs in 20% of cases, is a febrile syndrome which causes flu-like symptoms.
• West Nile Neuroinvasive Disease
(WNND), which occurs in less than 1%
of cases, is when the virus infects the CNS resulting in meningitis,
encephalitis, meningoencephalitis or a poliomyelitis-like syndrome.
• West Nile virus encephalitis (WNE) is the most common neuroinvasive
manifestation of WNND. WNE presents with similar symptoms to other viral encephalitis with fever,
headaches, and altered mental status.
• West Nile meningitis (WNM) usually involves fever, headache, and stiff neck.
• West Nile meningoencephalitis is inflammation of both the brain (encephalitis) and meninges (meningitis).
• West Nile poliomyelitis (WNP), an acute flaccid paralysis syndrome
associated with WNV infection, is less common than WNM or WNE.
45
2) Poliomyelitis (폴리오, 회색질척수염) refers to CNS infection by a single-stranded RNA virus
• an acute, viral, infectious disease spread from person to person, primarily via the fecal-oral route.
• Inflammation of the spinal cord’s grey matter fever, headache, & malaise
meningitis & variable paralysis
• Death can result from respiratory failure following paralysis of the respiratory muscles.
3) Rabies (광견병) is a fatal
infection transmitted by animal saliva
• a viral disease that causes acute encephalitis in warm-blooded
animals.
• The disease is zoonotic, meaning it can be transmitted from one
species to another, such as from dogs to humans, commonly by a bite from an infected animal.
A man with an atrophied right leg due to
poliomyelitis
Dog with rabies virus
4) Herpes simplex virus (단순헤르페스바이러스) is the most common cause of nonepidemic encephalitis (비유행성 뇌염)
• Herpes simplex virus type 1 (HSV-1) results in swollen, hemorrhagic, necrotic brain parenchyma, with perivascular lymphocytic cuffing
• Herpes simplex virus type 2 (HSV-2) (genital herpes) newborns during passage through the birth canal severe neonatal
encephalitis
Herpes simplex encephalitis. The infected
neurons display intranuclear, eosinophilic viral inclusions (Cowdry A inclusions) that fill the nuclei (arrows). The presence of these findings is extremely valuable in guiding diagnostic
evaluation as a limited number of viruses produce Cowdry A inclusions.
Herpes simplex encephalitis. Microscopically, the specimen exhibits pronounced
perivascular lymphocytic inflammation. This finding indicates that active inflammation is present, but is not etiologically specific.
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6) Subacute sclerosing
panencephalitis (SSPE, 아급성 경 화 범뇌염) is caused by the
measles virus
• 홍역바이러스에 의해 야기되는 드문 5) Arbovirus encephalitis (아르보바
이러스 뇌염) are transmistted to humans by infected mosquitos or tick bites
• St. Louis encephalitis
• Western equine encephalitis
• Tickborne encephalitis
• From flulike symptoms to
meningoencephalitis associated with severe inflammation of the gray matter, necrosis, & vessel thrombosis
• Chronic long-term sequelae:
mental retardation, neurologic deficits, particularly in young children.
7) Progressive multifocal
leukoencephalopathy (PML, 진행다
초점백색질뇌증) most often affects immunocompromised patients
• A rare and usually fatal viral disease characterized by progressive damage or
inflammation of the white matter of the brain at multiple locations.
• Caused by viruses, the JC virus &
SV40 which is normally present and kept under control by the immune system.
• It occurs almost exclusively in people with severe immune deficiency, such as transplant patients on immunosuppressive medications, receiving certain kinds of chemotherapy, receiving natalizumab for multiple sclerosis, on long-term efalizumab (Raptiva) for psoriasis, or have AIDS.
• Death often occurs within 6 months.
8) AIDS encephalopathy is often a primary manifestation of HIV
infection of the CNS
• Occurs as a direct effect of
macrophage & microglial infection by the HIV-1 retrovirus
• A Primary encephalopathy
• A leukoencephalopathy
• A lymphocytic meningitis
AIDS dementia complex
Human
immunodeficiency virus (HIV)
encephalitis or encephalopathy (HIVE).
Multinucleated
giant cells (arrows) often in a
perivascular location are characteristic of HIV encephalitis.
Inset. 49