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Flashcards in L73 Deck (37):
1

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

HSV 1 & 2
VZV
All neurotrophic

2

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

CMV
EBV
HHV 6
Can all cause mono

3

Compare & contrast lympo vs neurotrophic viruses.

BOTH can infect epithelium
Only lympho can infect lymphocytes/other immune cells

4

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

LARGE dsDNA genome
Capsid
Tegument
Envelope

5

What are the 3 categories of CMV genes?

IE - immediate early
E
L

6

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

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

7

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

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

8

L genes:
Fxn
Where & when in cell

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

9

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

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

10

What do microRNAs do?

Control viral & cellular gene expression

11

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

Permissive = lytic infection
Latent
Persistent

12

Which tissue & cell type is permissive CMV found in?

Epithelial cells
Macrophages

13

Which cells is latent CMV in?

Hemopoietic cells (in bone marrow & liver)

14

Which cells is persistent CMV in?

Lymphocytes
Endothelial cells
Bone marrow stroma

15

Which pt populations are you concerned about for CMV?

Babies - common cause infectious birth defects
IC pts - 1ary or 2ary infection

16

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

CD8
Aka CD8 is most important for keeping CMV from reactivating

17

Why do you think about CMV in transplant pts?

CMV+ recipient could receive another strain from the donor
Recipient IC - can't fight off new strain

18

How can CMV be transmitted?

Most impt:
- Blood transfusions (if right CMV filter not applied)
- Bone marrow or solid organ transplant

19

Which transplant is the exception to CMV concerns?

Bone marrow - replacing entire immune system including previous immunity!

20

Most common CMV presentation?

Asymptomatic

21

CMV diseases in normal pts

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

22

CMV diseases in IC pts

MOST ORGAN SYSTEMS
Retinitis
Hepatitis
Gasteroenteritis
Colitis
Pna
Glomerulopathy
Disseminated disease

23

Describe CMV pna CXR

"Polar bear in snow storm"

24

What cells will you see in CMV biopsy?

Owl's Eye Cell - BIG epi cells
- Lungs
- GI (colitis)
- Kidneys

25

What is a distinctive characteristic of CMV in lesions?

Hemorrhage

26

Describe CMV retinitis

1. Micro-infarcts = white dots (not specific to CMV)
2. Progress to hemorrhagic ("ketchup on scrambled eggs")

27

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

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

28

Which CMV disease is specific to babies? Symptoms.

Cytomegalic inclusion disease of the newborn
- Microephaly
- Mental retardation

29

What is the immune response to CMV?

Abs & cell mediated (CD4, 8, NK)

30

Diagnose CMV

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

31

What does Shell Vial rapid culture measure?

Abs vs IE & E antigens

32

How do you filter CMV out of blood?

Exclude cells w/ buffy coat

33

Drugs for CMV prophylaxis

Ganciclovir
Valgan
(Acyclovir)

34

Antiviral to treat CMV

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

35

Ganciclovir tox

Bone marrow

36

Foscarnet tox

Renal (not if Cr

37

How do you get ganciclovir (& valgan) resistance?

1. (most likely) UL 97 mutation = CMV kinase
2. UL 54 mutation = DNA pol