Herpeseviruses (CMV, EBV, VZV, HHV-6, HHV-8) Flashcards Preview

Virology > Herpeseviruses (CMV, EBV, VZV, HHV-6, HHV-8) > Flashcards

Flashcards in Herpeseviruses (CMV, EBV, VZV, HHV-6, HHV-8) Deck (25):
1

unique contents of CMV tegument

carries mRNA and pp65(diagnostic protein)

interesting that it is a dsDNA virus, but carries mRNA

1

VZV tropism

permissive in mucoepithelial cells(skin)

latent in neurons

2

malignancies caused by EBV

Burkitt's lymphoma

nasopharyngeal carcinoma

post-transplant lymphoproliferative disorder

some hodgkins lymphomas

3

treatment for HHV-6

ganciclovir, foscarnet

indicated for exanthem subitum(roseala)

4

clinical manifestation of VZV(reactivation)

complications?

shingles/zoster

VZV reactivates from latent DRG; vesiculopapular rash in dermatomal distribution

 

complications:

  • ramsey-hunt syndrome(reactivation from geniculate ganglion) - vesicles in external auditory meatus
  • guillan-barre syndrome: ascending bilateral paralysis; 

4

shingles complications in immuncompromised

pneumonitis, hepatitis, meningoencephalitis

longer lasting rash and dissemination

6

describe the tropism of CMV during:

permissive

latent

and persistent infections

permissive = epithelial cells, fibroblasts, macrophages

latent = infects hematopoeitic cells

persistent = lymphocytes, endothelial cells, BM stroma

 

7

treatment/prophylaxis for CMV

specific treatment for CMV pneumonitis, retinitis

 

ganciclovir(BM toxicity)

foscarnet(renal toxicity)

hyperimmune globulin w/ganciclovir OR foscarnet for CMV pneumonitis in BMT pts

valganciclovir for retinitis

7

clinical manifestation of HHV-8

kaposi's sarcoma

primary effusion lymphoma - b lymphocyte infection

multicentric calstleman's disease - b cell lymphoma

8

lymphotrophic AND angiotrophic herpesevirus

HHV-8

kaposi's

9

treatment for VZV

for chickenpox: acyclovir (use IV is immunocompromised)

for shingles, can bump it up to famciclovir, valacyclovir(still use IV for immunocompromised)

9

HHV-8 transmission, treatment

sexually transmitted

ganciclovir, valganciclovir, foscarnet

10

clinical manifestation of VZV(primary)

complications?

chickenpox - resp. tract infected; spread to blood/lyph; eventually reticuloendothelial cells; then skin

complications: acute cerebellar ataxia, meningoencephalitis, pneumonitis, hepatitis

  • reyes syndrome: kids taking aspirin during chickenpox; fatty liver and encephalopathy

11

neurotropic herpesviruses

HSV-1, HSV-2, VZV

13

describe permissive, latent, persistent infections

permissive = lytic; producing infectious viral progeny

latent = silent genome persistence; nonlytic

persistent = low lvl of viral prgeny, nonlytic on cell level

15

CMV diagnosis

shell rapid CMV culture(uses IE and E antigens, pp65) - 12-24hrs

owl's eye cell - cytomegalic inclusions

16

clinical manifestation of EBV?

manifestations of EBV in immunocompromised ?

  • heterophile positive mononucleosis; virus in saliva, kissing disease
  • autoimmune disease(ITP, hemolytic anemia)
  • RASH w/AMPICILLIN;  mono has exudative pharyngitis, making it look like GAStrep infection; Ampicillin is perscribed and if a rash forms, EBV is almost pathopneumonic

Immunocompromised

  • post transplant lyphoproliferative disorder - solid organ and BMT recipients
  • hairy oral leukoplakia - white patches on lateral surface of tongue in AIDS pts
  • Burkitt's lymphoma 

17

prophylaxis for EBV

acyclovir, ganciclovir, valganciclovir

19

manifestation of CMV in immunocompetent, immunocompromised

immunocompetent: 80-90% asymptomatic - heterophile negative mononucleosis - idiopathic thrombocytopenic purpura

hemolytic anemia

immunocompromised: primary OR reactivated -

  • retinitis(especially AIDS)
  •  pneumonia(especcialy BM recipients)
  • hepatitis, gastroenteritis, glomerulopathy
  • disseminated disease

20

tissue tropism for EBV

permissive and latent infections pursue lymphocytes(mostly B), and oral/nasopharyngeal epithelium

 

21

leading infectious cause of birth defects in US

cytomegalovirus

22

clinical manifestation of HHV-6

exanthem subitumroseola rash(fever then maculopapular rash)

heterophile negative mononucleosis(like CMV)

BM suppression; delayed engraftment in BMT recipients

23

how does CMV evade immune system?

downregulation of MHCI,II antigens

inactivation of interferon genes

24

general structure of herpesviruses

enveloped dsDNA w/icosahedral, capsule, tegument, and IE, E and L proteins

25

lymphotrophic herpesviruses

EBV, CMV, HHV6

maculopapular rash, causes of ITP, mononucleosis w/atypical lymphocytosis