Exam 3 - Herpesviruses Flashcards
1
Q
Herpes
3 categories
A
alpha (HSV, VZ)
beta (CMV, HHV6)
gamma (EBV, HHV8)
2
Q
Herpes
herpesviridae
morphology
A
-large, enveloped, dsDNA
-env. from host cell w/
viral glycoproteins
-nucleocapsid, tegument
-non-distinct in microscopy
3
Q
Herpes
herpesviridae
latency
A
- alpha: neurons
- beta: mono/lymphocytes
- gamma: B lymphocytes
4
Q
Herpes
HSV
path
A
- replication in epithelium
- buds from host cell
- syncytia possible
- lysis, inflamm response
- latency in sens root ganglia
5
Q
Herpes
HSV
latency
A
- retrograde axonal transport
- latent in sens root ganglion
6
Q
Herpes
HSV
reactivation stimuli
A
UV light, stress, trauma,
immune suppression, menstruation
7
Q
Herpes
HSV
epi/transmiss
A
- Women>Men
- direct contact
8
Q
Herpes
HSV
Primary Infxn Sx
A
- 2-7 day incubation
- fever, anorexia, malaise, headache
- regional lymphadenopathy
- severe vesicular rash
- lesions heal after several wks
9
Q
Herpes
HSV
Gingivostomatitis Sx
A
- 2-12 day incubation
- children <5 yrs
- vesicles/ulceration soft palate, tongue, floor
- oral pain, lymphadenopathy
- 10-14 days
10
Q
Herpes
HSV
Recurrent Infxn Sx
A
- sterotyped lesions
- fewer in # than primary
- HSV2>HSV1
- prodrome: itch, tingle, burn
- heal 8-10 days
11
Q
Herpes
HSV
Asymptomatic Shedding
A
-2% of days
-most common w/in 7 days
of recurrence
-HSV 2> HSV 1
12
Q
Herpes
HSV
Neonatal Tranmiss
A
- 30% transmiss w/ active lesions
- C-section indicated
- HSV 1 or 2
13
Q
Herpes
HSV
Neonatal Sx
A
-seizures, blindness, DD,
psychomotor agitation, spasticity
…death
14
Q
Herpes
HSV
Dx
A
- clinical
- Tzanck (giant multinuc cells)
- viral culture
- PCR
15
Q
Herpes
HSV
Tx
A
-acyclovir (thymidine kinase
inhibitors)
16
Q
Herpes
VZ
path
A
- similar to HSV
- varicella=primary
- zoster=recurrence
17
Q
Herpes
VZ
transmiss/epi
A
- respiratory route
- highly contagious
- winter/spring
- children
- temperate zones
- contagion starts 5 days before sx
18
Q
Herpes
VZ
Sx
A
- 14-15 day incubation
- fever, rash (scalp/trunk->extremities)
- vesicles, various stages
- ulceration on membranes
19
Q
Herpes
VZ
Dx
A
-clincial dx
-Tzanck prep from ulcer base
(giant multinuc cells)
20
Q
Herpes
VZ
Tx
A
- acyclovir
- higher dose than for HSV
21
Q
Herpes
VZ
Complications
A
- hepatitis
- pneumonitis
- encephalitis
- staph/strep co-infection
- Reyes, Guillain-Barre
22
Q
Herpes
VZ
Latency
A
- “zoster”
- dorsal root ganglia
23
Q
Herpes
VZ
Reactivation stimuli
A
- stress
- age
- immunosuppression
24
Q
Herpes
VZ
Recurrence Sx
A
- dermatomal distribution (1-3) (50% thoracic)
- unilateral
- prodromal pain
- dissem to brain, liver, lung MAY occur
- post-herpetic neuralgia (>1 mo), ^ w/ age
25
Herpes
VZ
vaccine
- live atten'd Oka strain
- in US since 1995
- given to children, >60yo
26
Herpes
EBV
morphology
- gamma herpesvirus
| - dsDNA circular, capsid, envelope, glycoproteins
27
Herpes
EBV
transmiss/epi
- US infxns in adolescents, young adults
- 90% US adults have serum Ab
- transmit through "close personal contact"
28
Herpes
EBV
path
- replication in pharyngel lymph tissue
- dissemination via lymphoretic. system
- infected B cells can become malignant
29
Herpes
EBV
clinical/sx
-infxous mononucleosis
-sore throat, fever, lymhpadenopathy
tonsilar englargement w/ exudate, palatal petechiae
-splenomegaly, hepatomegaly
-rash caused by ampicillin
-various secondary lymphomas
30
Herpes
EBV
complications
- hemolytic anemia, thrombocytopenia
- splenic rupture
- neurologic dz
31
Herpes
EBV
latency/recurrence
- B cell latency
| - asymptomatic shedding
32
Herpes
EBV
dx
```
-"atypical" T-cell lymphocytes on
peripheral blood film
-elevated transaminases
-heterophile antibody agglutination on
horse RBCs (Weird) ("Monospot")
-antigen test
```
33
Herpes
CMV
morphology
- beta herpesvirus
- largest human virus!
- dsDNA linear, capsid, envelope
34
Herpes
CMV
path
- cytomegaly
| - downregulation of CD8 response
35
Herpes
CMV
transmiss/epi
- kissytimes, peetimes, sexytimes, bloodtimes, milkytimes
| - 60-100% adults seropositive
36
Herpes
CMV
clinical/sx
-imm. competent: asx or mono-ey
-imm. compromised: retinitis, pneumonitis,
colitis, esophagitis, encephalitis, myelitis
-congenital infxn: 30% have sx (hepatosplenomeg,
petech rash, microceph, motor dysfxn, retinitis)
37
Herpes
CMV
dx
- IgM (primary) or IgG (latency)
- assay, culture
- "owl's eye inclusions" (cytoplasmic nuclear incl)
38
Herpes
CMV
tx
-antivirals
39
Herpes
HHV6
morph
- Beta (see CMV morph)
40
Herpes
HHV 6
transmiss/epi
- saliva
- spring and fall
- 90% of 2 y.o. are seropositive
41
Herpes
HHV 6
path
-T, B, NK, Mac, glial, and epith cells
42
Herpes
HHV 6
clin/sx
-10 day incubation
-asx OR:
-fever, roseloa infantum (benign rash), fever
-abrupt defeverensce, macular rash ,
suboccipital lymphadenopathy, red throat
-rare febrile seizures and encephalopathy
-adults: mono-ish
43
Herpes
HHV 6
dx
-serologic testing
44
Herpes
HHV 6
tx
-not indicated
45
Herpes
HHV 8
morph
- gamma herpesvirus (see EBV)
| - aka Kaposi's Sarcoma-Ass'd Herpesvirus (KHSV)
46
Herpes
HHV 8
transmiss/epi
- sexytimes
| - 90% of Kaposi's sarcoma are HHV8+
47
Herpes
HHV 8
path
- infects epithelial spindle fibers (Kaposi's)
| - lymph tissue (lymphoma/Castleman's)
48
Herpes
HHV 8
clin/sx
- Kaposi's: mult vascular tumors
| - Castleman's: lymphoma
49
Herpes
HHV 8
latency
-(B) lymphocytes
