Microbiology 15: Antiviral Therapy

Question 1

What disease does EBV cause ?

Answer 1

Infective mononucleosis

Question 2

Where does Varicella Zoster Virus lay dormant in the body?

Answer 2

Dorsal root ganglia

Question 3

What is a complication of Chickenpox in adults?

Answer 3

Varicella pneumonitis

Question 4

What is a complication of shingles in adults ?

Answer 4

Post-herpetic neuralgia

Question 5

Which medication is 1st line for treatment of HSV and VZV ?

Answer 5

Aciclovir

Question 6

What type of anti viral is acyclovir ?

Answer 6

Nucleoside analogue

They get incorporated into growing chain of DNA causing it to terminate

Question 7

Give 2 reasons why aciclovir has reduced toxicity to normal cells compared to cells infected with a virus?

Answer 7

Aciclovir requires activation by viral thymidine kinase (found in cells infected by viruses)

Aciclovir has a higher affinity for Herpes virus DNA polymerase compared to human DNA polymerase

Question 8

Which medical emergency is caused by HSV ?

Answer 8

HSV encephalitis

Question 9

What is the characteristic histological appearance of CMV infection ?

Answer 9

Owl’s eye inclusions

Question 10

Which virus are immunocompromised patients particularly at risk of compared to immunocompetent people ?

Answer 10

CMV

Question 11

In which cells does CMV tend to lie dormant ?

Answer 11

Monocytes

Dendritic cells

Question 12

What anti viral treatments are used to treat CMV infection ?

Answer 12

Ganciclovir
Foscarnet
Cidofovir

Question 13

Which disease can EBV cause in immunocompromised patients ?

Answer 13

PTLD - post transplant lymphoproliferative disease

The EBV keeps dividing unless kept in check by the immune system
This causes polyclonal activation of B cells

Question 14

What does PTLD predispose to ?

Answer 14

B cell lymphoma

Question 15

What is the treatment for PTLD ?

Answer 15

Rituximab - monoclonal antibody against CD20 B cell surface marker

Question 16

What are the 2 main surface proteins on influenza virus ?

Answer 16

HA- haemaglutinin

NA- Neuraminidase

Question 17

Which disease is commonly caused by RSV ?

Answer 17

Bronchiolitis

Question 18

Who should palivizumab be given to prophylactically ?

Answer 18

High risk infants (preterm, heart or lung disease, SCID) in the winter months
Prevents severe disease from RSV

Question 19

Which 2 diseases does BK virus cause in immunocompromised patients?

Answer 19

Haemorrhagic cystitis in bone marrow transplant patients

BK nephritis in renal transplant patients

Question 20

Which immunomodulatory therapy is used to treat hepatitis B ?

Answer 20

Interferon Alpha

Question 21

Which antiviral drug is used to treat and prevent Influenza In the elderly?

Answer 21

Oseltamivir

Question 22

Which antiviral can be used in aerosol form to prevent RSV infection in children with heart and lung disease ?

Answer 22

Ribavirin

Question 23

Which ART is given to pregnant women with HIV ?

Answer 23

If already on ART don’t change it - most likely Zidovudine

Otherwise:
Nevirapine

Question 24

Which antiviral is the drug of choice for CMV infection ?

Answer 24

Ganciclovir

Question 25

What is the prodrug of aciclovir that can be used in VZV infection ?

Answer 25

Valaciclovir

Question 26

Which antiviral drug is used to treat severe resistant herpes infection ?

Answer 26

Foscarnet

Question 27

Which drug is effective against Influenza A but not Influenza B ?

Answer 27

Amantadine

Question 28

Which HIV drug works by inhibiting reverse transcriptase by acting as a guanine analogue?

Answer 28

Zidovudine

Question 29

treatment for HSV encephalitis

Answer 29

medical emergency | start empirical treatment with IV aciclovir 10 mg/kg tds without awaiting test results

Question 30

treatment for HSV meningitis

Answer 30

usually self limiting IV aciclovir 2-3 days, then switch to oral for 10 days valaciclovir alternative in immunocompetent to avoid cannulation

Question 31

indications for treatment for VZV

Answer 31

chickenpox in adults (risk of pneuonitis) shingles in adults >50 yrs ( risk of post-herpetic neuralgia) primary infection/reactivation in an immunocompromised patient neonatal chickenpox

Question 32

consequences of CMV in immunocompromised patients

Answer 32

bone marrow suppression, retinitis, pneumonitis, hepatitis, colitis, encephalitis

Question 33

treatment for CMV infection

Answer 33

ganciclovir (IV) - S/E = BM toxicity valganciclovir (PO) foscarnet (IV) - nephrotoxicity cidofovir (IV) - nephrotoxicity

Question 34

describe how viruses gain entry into cells

Answer 34

HA mediated virus binding and entry into target cell NA allows the release of progeny virus particles from the host cell NA is the target for current anti-influenza drugs

Question 35

treatment for RSV

Answer 35

(most common cause of bronchiolitis) ribavirin - neucleoside analogue IVIG - in immunocompromised palivizumab - monoclonal ab against RSV

Question 36

BK virus treatment

Answer 36

lifelong carriage in the kidneys and urinary tract problems in the immunocompromised BK haemorrhagic cystitis - bladder washouts, cidofovir IV BK nephropathy - reduce immunosuppression and IVIG

Question 37

adenovirus treatment

Answer 37

cidofovir IV IVIR brindcidofovir PO

Question 38

immunoglobulin preparations for post-exposure prophylaxis

Answer 38

VZIG hepatitis B ig human rabies IG