MED VIRO Flashcards
anterograde example
reactivation of herpes virus
Rabies are example of
retrograde.
to the cell body –> cns
Acute Disseminated Encephalo-myelitis (ADEM) is also known
Post-infectious encephalomyelitis
- autoimmune
aseptic meningitis treatment is
supportive
non envelope are
very togh
Poliomyelitis–
spinal cord
poliomyelitis control
there is a polio vaccine derived
Vaccines
* OPV (live attenuated, Sabin 1/2/3)
* IPV (killed, Salk)
Laboratory Diagnosis
of enteroviruses
PCR
– More easily available
– CSF, stool, (respiratory samples)
when you suspect herpes simplex encephilitis you need to
react fast, the patient will done
A patient with meningitis would clinically present with (4):
- Headache
- neck stiffness
- photophobia
- nausea and vomit
—–> with normal brain function (i.e., no focal neurologic)
Patient with encephalitis generally present with: (1)
Altered brain function
What is myelitis?
inflammation of the spinal cord
Symptom triad of aseptic meningitis.
Fever, meningitis irritation, headache
Most common causes of viral meningitis. (3)
- Enterovirus (< 1y/o)
- HSV (HSV-2 adults)- Mollaret’s meningitis
- Mumps- MMR vaccine
Human enteroviruses
(4)
(stable in acidic pH)
- Echoviruses
- Enteroviruses
- (Coxsackieviruses)
- (Polioviruses poliomyelitis)
Which part of the brain often affected by HSV encephalitis
temporal lobes
Emergency treatment for HSV encephalitis.
acyclovir
Risk factors for CMV encephalitis (2)
- HIV‐associated + immunocompromised
Paramyxoviruses : (2)
- Mumps
- Measles
Measles inclusion body encephalitis
(MIBE) risk factor
- Immune‐compromised patients
What would be your management if the present with category 1
Hx: Touching/feeding animal, licking of intact skin
No action if reliable history
How would you manage a patient with exposure rabies
Hx: Scratch (no bleeding,) nibble, or lick of broken skin
vaccine
Category 3: Lick of mucous membranes, bites or scratches that draw blood
How would you management?
Vaccine + Rabigam
Is it a good or bad idea to test for virus in a CSF in a patient with Post-infectious encephalomyletis? Why ?
For post-infectious encephalomyelitis, the disease
is due to immunopathology thus the virus that
triggered the disease would not be present in CSF.
PCR would not be a useful diagnostic test here
Antibody tests like IgG or IgM to specific viruses are
not very useful either.
Pathophysiology Acute Flaccid Paralysis
Enteroviruses and polio virus enter through the gut and enters CNS via blood stream
Virus replicates in the cell body of neurons
The viral replication is cytolytic
Pathophysiology of Post-infectious encephalomyelitis
Following a viral infection in some
individuals, T- cell confused the myelin in
the brain with viral antigen epitope
This results in white matter lesions
in the CNS
“Molecular mimicry”
This can also happen in peripheral nerves –
Guillain Barre syndrome (see resource pack)
Which viruses can spread to the central nervous system via retrograde axonal transport?
Herpes simplex virus (HSV) and rabies virus
Which cranial nerve can be used as a route of entry for certain viruses to reach the brain?
Olfactory nerve
What is the most common symptom triad seen in viral aseptic meningitis?
Fever, meningeal irritation, and headache
Which type of viruses are stable in acid pH and can cause aseptic meningitis?
Enteroviruses
What is the most common cause of sporadic viral encephalitis?
Herpes simplex virus (HSV)1
Which virus is responsible for causing subacute sclerosing panencephalitis (SSPE)?
Measles virus
Which virus is associated with post-infectious encephalomyelitis (PIEM)?
Rubella virus
Which arbovirus is transmitted by mosquitoes and can cause diseases like Rift Valley fever and West Nile fever?
West Nile virus
What is the recommended treatment for suspected cases of rabies infection in humans?
Post-exposure prophylaxis with rabies vaccine and administration of rabies immunoglobulin if necessary.
Which viral infection is the most common cause of sporadic viral encephalitis?
a) Measles
b) Rabies
c) Herpes simplex
d) Mumps
c
Which viral family does the causative agent of poliomyelitis belong to?
a) Paramyxoviridae
b) Picornaviridae
c) Herpesviridae
d) Flaviviridae
B
Which neurological syndrome is characterized by cognitive dysfunction, dementia, seizures, ataxia, and coma, and is associated with JC virus infection?
a) Progressive multifocal leukoencephalopathy (PML)
b) Measles inclusion body encephalitis (MIBE)
c) Subacute sclerosing panencephalitis (SSPE)
d) Acute disseminated encephalomyelitis (ADEM)
A
