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Flashcards in L74 Deck (53):
1

What receptor confines the tropism of EBV?

CR2 receptor

2

Which tissues and cells does EBV infect?

B lymphocytes
Mouth & nose epithelium
Also an STI b/c in vaginal secretions from the cervical epi, but weird b/c no CR2Rs here

3

Can EBV have a lytic stage of infection?

Yes
In B cells & epithelium

4

Can EBV have a latent stage of infection?

Yes
More common in B cells

5

What genetic element allows EBV to become latent?

Episome

6

What is the worst case scenario of an EBV infection?

CANCER

7

What cancers are EBV associated?

B cell lymphoma - Burkitt
Nasopharyngeal carcinoma
Post transplant lympho-proliferative disorder (PTLPD)
Maybe other T & B lymphomas (Hodgkin's)

8

Most common EBV disease in normal people.

Mono - aggultinin + !!

9

EBV transmission

Saliva
Blood product
Transplant
STI

10

How do you know staph vs EBV pharyngitis?

Present in clinic
Probably going to give penicillin (ampicillin)
EBV gets a RASH --> doesn't get better

11

Which arm of the immune system is most important in controlling EBV latent infection?

T cells

12

What is a cue that a pt is EBV infected during the acute phase?

See atypical lymphocytes on peripheral blood smear

13

Describe the Ab response to EBV in terms of symptom progression.

1. Before symptoms: IgM/IgG vs E antigens
2. Symptomatic: IgM Abs that agglutinate!!!
3. Resolving: Abs vs EBNA

14

What is EBNA?

Epstein Barr nuclear antigen
See Abs vs these - know infection is resolving

15

What is a neurologic disorder you might see with EBV in normal pts?

Guillain Barre - ascending paralysis

16

If an AIDs negative IC pt presents with falling CD4 ct + EBV infection, which clinical disease are you thinking of?

B cell (Burkitt) lymphoma
May present w/ malaria

17

Which EBV infection is most common in HIV pts?

Hairy oral leukoplakia

18

Which EBV infection is most common in transplant pts?

Post transplant lympho proliferative disorder

19

Describe the progression of PTLD.

Early = benign growth that respond to anti-virals
Late = malignant growths

20

How does PTLD present on histo?

HISTO: multi-nucleated giant cells

21

Diagnose EBV

1. PCR for EBV DNA
2. Immunocytochem for EBV proteins

22

EBV prophylaxis

Acyclovir
Gancyclovir (valgan)

23

Treat EBV mono

Supportive
Severe: steroids - prevent spleen damage

24

Can you treat EBV cancers with anti-virals?

No you dummy
That's why you don't what to progress this far - need chemo

25

Treat PTLD

Non-specific immunoglobulin
IFNa
Chemo
Rituximab (anti-CD20)

26

Name the 2 big diseases caused by VZV.

Chicken pox
Shingles

27

What does the chicken pox rash look like?

Infects EPI cells - duh, why its a rash!
Blistering rash
May also be pustular
At all different levels of progression

28

Why does it matter that VZV is neurotropic?

Reactivate (Shingles) = painful lesions

29

When in the disease does the chicken pox rash occur?

2nd!
Infection
1. Prodrome viremia = 9-13 days post-infection
2. Rash on face/scalp first, then trunk = 10-20 days post-infect

30

Where does VZV lie dormant?

DRG
CN ganglia

31

Who is most likely to get chicken pox complications?

IC pts: newborns, pregnant, transplant, AIDs

32

Complications of chicken pox

CNS
Lungs: pneumonitis
Liver
Reye's syndrome - aka don't give aspirin to kids!!!

33

Hallmarks of Shingles rash

Vesiculopustular
Painful
Stops at midline

34

Shingles complications

Post-herpetic neuralgia
If CN 5 involvement --> encephalitis

35

What is the Shingles complication if there is geniculate ganglion involvement?

Ramsey Hunt Syndrome
- 1 sided facial palsy
- Lesions in ear
- Loss taste ant 2/3 tongue

36

Immune response to VZV

IgM + IgG - limit spread
CD4 - resolve rash

37

You're probably diagnosing CP/Shingles clinically, but if you really wanted to what test would you order?

Pap smear of a lesion
Direct fluorescent Ab
PCR of CSF if neuro involvment

38

What is the chicken pox vaccine?

Live, attenuated
2 shots
Prevents chicken pox in kids & decreases shingles in elderly

39

Which vaccine do you give to IC pts?

VZIG = immunoglobulin
Ex: pregnant women who have been exposed to chicken pox
Babies whose mothers have chicken pox

40

When and how do you treat chicken pox?

24 hrs of 1st lesion: PO acyclovir
Otherwise supportive

41

How do you treat IC pts with chicken pox?

Acyclovir IV

42

When and how do you treat Shingles in normal pts?

72hrs of 1st lesion: 7 day course of PO
- Acyclovir
- Famciclovir
- Valacyclovir

43

Which shingles complication/presentation should you always treat?

Opthalmic zoster

44

How do you treat shingles in IC pts?

IV acyclovir
Goal: decrease severity + speed healing

45

When does HHV 6 infection occur in life in comparison to CMV and EBV?

Earlier in life!

46

Which skin disease is most common in kids due to HHV6?

Roseola = exanthem subitum
1. Fever
Followed by
2. Red, raised rash w/o fever

47

Which conditions would clue you into an HHV 6 infection in kids AND adults?

Mono
Seizures in kids
Delayed bone marrow grafts in bone marrow transplant pts
DRESS syndrome = drug rxn eosinophila w/ systemic symptoms

48

Diagnose HHV6 infection.

Clinical
Serology: IgM & IgG
PCR

49

What 3 characteristics are unique about HHV8?

1. Tumor promoting genes
2. Lympho AND angiotrophic
3. Has proteins homologous to cell proteins

50

Which tissues does HHV8 infect?

Uro & GI epithelium

51

How does HHV8 lie latent?

Episome - contributes to oncogenic reactivation

52

Where in the world are HHV8 infections most prevalent?

Mediterranean + Africa

53

HHV8 transmission

Sex***
Mom-baby
Oral
Blood