Varicella-Zoster Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

What family?

A

Herpesvirus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How many serotypes?

A

1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the 2 diseases it causes?

A
  1. Varicella (chickenpox) - primary illness
  2. Zoster (shingles) - recurrent manifestation of infection
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the clinical presentations of varicella?

A
  • Fever
  • Crops of vesicles in waves and more on trunk than extremities (centripetal distribution)

Usually more severe symptoms in adults than children

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the complications of varicella?

A
  • Skin infection (staphylococci/streptococci)
  • Aseptic meningitis
  • Neurological syndrome
  • Post-infectious encephalomyelitis (one week after rash)
  • Pneumonia (cough, dyspnoea, hypoxia, diffuse nodular infiltrate, pulmonary calcification - may be fatal)
  • Haemorrhagic (thrombocytopenia, DIVC)
  • Arthritis
  • Congenital varicella (rare transplacental infection in neonates born to mothers with varicella in early pregnancy)
  • Neonatal varicella
  • Overwhelming varicella (immunosupressed patients)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How to treat varicella?

A
  • Symptomatic (antipyretics, antipruritics)
  • Varicella-zoster immune globulin (VZIG) prophylaxis in exposed high-risk immunocompromised children
  • Acyclovir (severe varicella pneumonia/haemorrhagic varicella)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How is varicella transmitted?

A
  • Nose and mouth by droplet infection from infectious saliva
  • Contact with skin lesions of varicella cases
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How to control varicella?

A
  • Barrier nursing and isolation of immunosupressed patients
  • VZIG prophylaxis
  • Live attenuated vaccine for high-risk patients and even healthy subjects
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Where does zoster take place? How does zoster come about?

A
  • Recrudescent disease occuring in dermatome of sensory nerve ganglion
  • Reactivation of latent VZV (usually long period after childhood varicella, more frequent in old age and immunocompromised)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the clinical presentations of zoster?

A

Painful vesicular eruption morphologically similar to varicella

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the skin distribution of zoster?

A
  • 50%: thoracic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the complications of zoster?

A
  • Encephalomyelitis (lymphocyctic pleocytosis in CSF)
  • Post-herpetic neuralgia (often in elderly)
  • Disseminated zoster (vesicles outside involved dermatomes in immunosupressed)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the treatment of zoster?

A

Acyclovir IV (can limit progression of zoster if given early, even in immunocompromised)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How to prevent zoster?

A

Zoster vaccine for >50y/o

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Who does zoster mostly occur in?

A

Mainly adults

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How is zoster acquired?

A

Sporadic without seasonal distribution
Not acquired by contact with zoster cases

17
Q

How to diagnose VZV?

A
  1. Vesicles
    - stained smears of scrapings of swabs from base (multinucleated giant cells)
    - Immunofluorescent (intracellular viral antigens)
    - PCR
  2. Virus isolation
    - in human fibroblast cultures (focal CPE, cell associated virus)
    - IF, NT of isolate with specific antisera
  3. Serology
    - IgM found in both recent varicella and zoster
    - Rise in Ab titre
    - High levels of neutralising Ab in zoster