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Flashcards in L73 Deck (37)
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1
Q

Which are the alpha herpes viruses? Why are they grouped together?

A

HSV 1 & 2
VZV
All neurotrophic

2
Q

Which are they lymphotrophic herpes viruses? What disease can all of these viruses cause?

A

CMV
EBV
HHV 6
Can all cause mono

3
Q

Compare & contrast lympo vs neurotrophic viruses.

A

BOTH can infect epithelium

Only lympho can infect lymphocytes/other immune cells

4
Q

Name the 4 structural aspects of CMV that you need to know (think inside –> out).

A

LARGE dsDNA genome
Capsid
Tegument
Envelope

5
Q

What are the 3 categories of CMV genes?

A

IE - immediate early
E
L

6
Q

IE genes:
Need protein synthesis?
Fxn
Where & when in cell

A
DON'T need protein synthesis
Gene products fxn in viral DNA synthesis
Detected:
- Nucleus 
- 1st (12-20 hrs post infection)
7
Q

E genes:
Need protein synthesis?
Fxn
Where & when in cell

A

Need protein synthesis to create gene products
–> fxn in DNA replication + viral protein mod
Detect:
- Cytoplasm
- Nucleus

8
Q

L genes:
Fxn
Where & when in cell

A

Gene products = structure
Cytoplasm
Nucleus
Last - 48hrs post infection

9
Q

What genetic material is found in CMV’s tegument? What does it code for?

A

4 mRNAs
Code own IE, E & L genes
Code microRNAs

10
Q

What do microRNAs do?

A

Control viral & cellular gene expression

11
Q

What are the 3 types of infection timeframes that CMV can have?

A

Permissive = lytic infection
Latent
Persistent

12
Q

Which tissue & cell type is permissive CMV found in?

A

Epithelial cells

Macrophages

13
Q

Which cells is latent CMV in?

A

Hemopoietic cells (in bone marrow & liver)

14
Q

Which cells is persistent CMV in?

A

Lymphocytes
Endothelial cells
Bone marrow stroma

15
Q

Which pt populations are you concerned about for CMV?

A

Babies - common cause infectious birth defects

IC pts - 1ary or 2ary infection

16
Q

If compromised, lacking which form of immunity is most likely to cause CMV activation/infection?

A

CD8

Aka CD8 is most important for keeping CMV from reactivating

17
Q

Why do you think about CMV in transplant pts?

A

CMV+ recipient could receive another strain from the donor

Recipient IC - can’t fight off new strain

18
Q

How can CMV be transmitted?

A

Most impt:

  • Blood transfusions (if right CMV filter not applied)
  • Bone marrow or solid organ transplant
19
Q

Which transplant is the exception to CMV concerns?

A

Bone marrow - replacing entire immune system including previous immunity!

20
Q

Most common CMV presentation?

A

Asymptomatic

21
Q

CMV diseases in normal pts

A

Mono - won’t agglutinate
Idiopathic thrombocytopenic purpura
Hemolytic anemia
Hepatitis

22
Q

CMV diseases in IC pts

A
MOST ORGAN SYSTEMS
Retinitis
Hepatitis
Gasteroenteritis 
Colitis
Pna
Glomerulopathy
Disseminated disease
23
Q

Describe CMV pna CXR

A

“Polar bear in snow storm”

24
Q

What cells will you see in CMV biopsy?

A

Owl’s Eye Cell - BIG epi cells

  • Lungs
  • GI (colitis)
  • Kidneys
25
Q

What is a distinctive characteristic of CMV in lesions?

A

Hemorrhage

26
Q

Describe CMV retinitis

A
  1. Micro-infarcts = white dots (not specific to CMV)

2. Progress to hemorrhagic (“ketchup on scrambled eggs”)

27
Q

What brain/neural pathology might you see in CMV infection?

A

Periventriculitis = inflammation around ventricles in brain
- Also seen in HHV 6
Transverse myelitis/peripheral neuropathy
Hearing lose = CN8 involvment

28
Q

Which CMV disease is specific to babies? Symptoms.

A

Cytomegalic inclusion disease of the newborn

  • Microephaly
  • Mental retardation
29
Q

What is the immune response to CMV?

A

Abs & cell mediated (CD4, 8, NK)

30
Q

Diagnose CMV

A
= measure replication levels
1. PCR
2. Histopath/immunocytochem
Other
- Shell vial = rapid culture
31
Q

What does Shell Vial rapid culture measure?

A

Abs vs IE & E antigens

32
Q

How do you filter CMV out of blood?

A

Exclude cells w/ buffy coat

33
Q

Drugs for CMV prophylaxis

A

Ganciclovir
Valgan
(Acyclovir)

34
Q

Antiviral to treat CMV

A
Ganciclovir vs Foscarnet
- Use the other if resistent
Valgan (retinitis)
Cidofovir (retinitis only)
Hyperimmune globulin - in combos
35
Q

Ganciclovir tox

A

Bone marrow

36
Q

Foscarnet tox

A

Renal (not if Cr

37
Q

How do you get ganciclovir (& valgan) resistance?

A
  1. (most likely) UL 97 mutation = CMV kinase

2. UL 54 mutation = DNA pol