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Flashcards in L72 Deck (26):
1

Both strain of herpes:
Small or large?
DNA or RNA?
Envelope or no?

Large
DNA
Enveloped
Immune ok pts - more severe if IC

2

How does herpes replicate in the host?

Glycoprotein receptors (gD) engaged with host cells
Capsid enters cell
Synthesize viral DNA & proteins @ host nucleus
Assemble new viruses in host nucleus
Bud off host

3

What population is most likely to get HSV1 infections?

Kids!

4

What population is most likely to get HSV2 infections?

Women
Age not a limiting factor - throughout life

5

Herpes transmission

Infected mucosal surface shedding
HSV1 - oral or genital
HSV2 - genital
To infants during birth

6

Are condoms protective?

Partly - not 100% b/c of general groin infection

7

Describe the pathogenesis of herpes.

Into mucosal surface
Infect & replicate in epidermis & dermis
Infection moves into sensory & motor nerve endings
Moves up to ganglia and DORMANT here

8

Describe the pathogenesis of herpes reactivation.

IC, UV light, trauma, stress - induce reactivation
Virus moves out of ganglia --> down nerves --> cause mucosal lesions

9

Describe primary HSV 1 infection

ASYMPTOMATIC
Probably a kid - older more likely to be symptomatic:
- Fever
- "Feeling sick"
- Mouth/lip PAINFUL lesions

10

What is the primary HSV1 infection in kids?

Gingivostomatitis
- Mouth, lips, tongue

11

What are the 6 primary HSV1 infection in adults?

1. Acute herpetic pharyngotonsillitis
2. Herpetic Whitlow (fingers)
3. Herpes galditorum (abraded skin)
4. Ocular herpes
5. Herpes hepatitis
6. Bell's palsy (CN 7)

12

How do you differentiate between acute herpetic pharyngotonsillitis and other pharynx/tonsillar diseases?

Can only differentiate this from other things by PCR but you probably won't b/c self-limited

13

Which form of ocular herpes are you most worried about?

Acute retinal necrosis
- Necrotizing!!!
- Rapid progression --> blindness

14

Which form of ocular herpes causes dendritic lesions on the cornea?

HSV keratitis

15

What is a commonality for reactivation with HSV1 and HSV2?

If your initial infection was symptomatic, then you're likely to reactivate

16

What is unique about HSV1 reactivation?

Can have prodromal stage (tingling)

17

What are 3 the reactivation diseases for HSV1?

1. Oral-facial (aka mouth herpes is back)
2. Encephalitis
3. Esophagitis that presents with PAINFUL swallowing + small, shallow lesions

18

What is unique in diagnosis to help you determine HERPES encephalitis?

High RBCs in CSF from lumbar puncture
MRI = necrotization of temporal lobe

19

What is the presentation for primary HSV2 infection?

ASYMPTOMATIC
PAINFUL genital ulcers

20

How do babies get herpes? What is the presentation?

During birth from infected mothers
Skin-eyes-mouth (SEM)
High mortality if disseminated
High morbidity (cog defect) if neuro

21

How might HSV2 recur?

Ano-genital
Often with thymidine kinase resistant strains

22

Diagnose herpes

Clinical
PCR - especially if CSF involvement
Direct fluorescence Ab - antigen-Ab complex if virus present

23

Treat severe primary infection

Valacyclovir 1000mg PO 2x day

24

Chronic suppressive therapy

Pt with recurrence 6+ times per year
Vala 500mg PO daily

25

Serious herpes infection treatment

IV acyclovir *nephrotoxic*

26

Treatment if serious herpes infection is resistant to acyclovir

Resistant due to TK deficient virus
Foscarnet!!