Chapter 24
Viral Encephalitis
Clinton Jones and Eric Scholar
Questions
1.
The treatment of choice for west nile virus infection consists mainly of the use of
a. acyclovir
b. steroids
c. ganciclovir
d. supportive and symptomatic care
e. tetracyclines
2.
The most well known disease associated with cytomegalovirus infection is
a. genital infections
b. retinitis
c. hepatitis
d. dementia
e. multiple sclerosis
3.
Herpes simplex virus-2 infection occurs predominantly in
a. the elderly
b. women
c. homosexual men
d. cancer patients
e. sexually active adolescents
4.
Which of the following best describes the mechanism of action of acyclovir?
a. inhibition of reverse transcriptase.
b. stimulation of viral interferon production
c. inhibition of viral DNA polymerase
d. inhibition of viral protein synthesis
e. inhibition of de nove purine synthesis
5.
Intravenous administration of acyclovir is most likely to cause
a. anaphylactic shock
b. renal toxicity
c. liver toxicity
d. bone marrow suppression
e. cardiac arrhythmias
6.
The main advantage of valacyclovir compared to acyclovir is
a. a very short half life
b. better oral bioavailability
c. less renal toxicity
d. it is useful for the treatment of HIV infection
e. it has fewer drug interactions
7.
Ganciclovir is best used for the treatment of
a. West Nile virus
b. Herpes simplex encephalitis
c. Bird flu
d. Cytomegalovirus
e. Herpes zoster
24 Viral-Induced Encephalitis
Clinton Jones and Eric Scholar
2
8.
The major adverse effect associated with the use of cidofovir is
a. bone marrow suppression
b
rashes
c. arrhythmias
d. headaches
e. nephrotoxicity
9.
Foscarnet is
a. a purine nucleoside analog
b. a pyrimidine nucleoside analog
c. incorporated into DNA resulting in inhibition of chain elongation
d. an inorganic pyrophosphate analog
e. a select inhibitor of RNA polymerase
10.
Which of the following viruses causes encephalitis only in newborn children?
a. West Nile Virus
b
Herpes simplex virus type 1
c. Human cytomegalovirus
d. Varicella virus zoster
e. All of the above
11.
Why is HSV-1 induced encephalitis (HSE) difficult to treat with antiviral therapeutic drugs?
a. Anti-viral drugs do not work because only drug resistant strains cause encephalitis
b. Many cases of encephalitis are the result of reactivation from latency
c. Early stages of infection are asymptomatic
d. Anti-viral drugs do not cross the blood brain barriers
e. All of the above
12.
Circle all of the viruses that have the potential to induce encephalitis and establish a latent infection in
neurons?
a. HSV-1
b. Human cytomegalovirus
c. West Nile Virus
d. Varicella virus zoster
e. SV40
13.
The immediate early genes encoded by all herpes viruses regulate
a. viral entry into permissive cells
b. viral DNA replication
c. production of antibodies by B cells
d. viral gene expression
e. all of the above
14.
Is there a perfect correlation between the ability of viruses to replicate in the brain and induce
encephalitis? Justify your answer.
15.
If you were going to study viral induced encephalitis, would you choose HSV-1 or VZV as a model to
identify viral genes that regulate the frequency of encephalitis? Give several reasons why you chose the
virus that you chose.
Fill in the blank
16.
_______________ is a member of the Flaviviridae and has been spread by mosquitoes in North
America.
24 Viral-Induced Encephalitis
Clinton Jones and Eric Scholar
3
17.
_______________is an alpha-herpesvirus family member that causes encephalitis and expresses LAT in
latently infected neurons.
18.
_______________ is an important opportunistic infection that causes retinitis in AIDS patients.
19.
_______________is an alpha-herpesvirus family member that causes chicken pox early in childhood
and can cause zoster late in life.
20.
Describe the clinical features commonly associated with Herpes Simplex encephalitis?
24 Viral-Induced Encephalitis
Clinton Jones and Eric Scholar
4
Answers
1.
d
2.
b
3.
e
4.
c
5.
b
6.
b
7.
d
8.
e
9.
d
10.
d
11.
b
12.
a&d
13.
d
14.
Is there a perfect correlation between the ability of viruses to replicate in the brain and induce
encephalitis? Justify your answer.
Usually, but not always. Sometimes the immune response to the virus infection in the brain is the crucial
factor that regulates the efficiency of encephalitis
15.
If you were going to study viral induced encephalitis, would you choose HSV-1 or VZV as a model to
identify viral genes that regulate the frequency of encephalitis? Give several reasons why you chose the
virus that you chose.
sHSV-1 because it grows better in cultured cells than VZV, there are good small animal models for HSV-1.
Fill in the blank
16.
West Nile is a member of the Flaviviridae and has been spread by mosquitoes in North America.
17.
HSV-1 is an alpha-herpesvirus family member that causes encephalitis and expresses LAT in latently infected
neurons.
18.
HCMV is an important opportunistic infection that causes retinitis in AIDS patients.
19.
VZV is an alpha-herpesvirus family member that causes chicken pox early in childhood and can cause zoster
late in life.
20.
Describe the clinical features commonly associated with Herpes Simplex encephalitis?
Two recognizable groups of symptoms are seen. Nonspecific symptoms, which include fever, headache,
meningeal irriation, nausea, vomiting, confusion, generalized seizures and alteration of consciousness. The
24 Viral-Induced Encephalitis
Clinton Jones and Eric Scholar
5
second group includes those referable to focal necrosis of the orbitofrontal and temporal cortexes and the
limbic system and includes anosmia, memory loss. Peculiar behaviour, speech defects, hallucinations and
focal seizures.