DNA Viruses Flashcards Preview

Microbiology Rapid Review > DNA Viruses > Flashcards

Flashcards in DNA Viruses Deck (35):
1

Enveloped hepadnavirus, common cause of acute viral hepatitis, becomes chronic in 10% adults, transmission to 90% infants, increases risk of hepatocellular carcinoma and cirrhosis

Hepatitis B Virus

2

Hepatitis D is a defective RNA virus. Which part of HBV does it seek out to become pathogenic?

HBsAg

3

What are the first antibodies to appear in an acute Hepatitis B infection?

HBcAb. Positive during window phase; if HbcAb IgM is present, this indicates a recent disease

4

Which antigen indicates transmissibility of HBV infection and determines active state in chronic hepatitis?

HBeAg

- if HBeAb is instead present, this indicates that the infection is chronic but not active

5

If HBsAb is present, what phase is the patient in?

Either immunized or has a history of a prior infection (HBeAb and HBcAB IgG will also be present in case of prior infection)

6

ssDNA, naked icosahedral parvovirus, erythema infectiosum, causes flu-like symptoms with facial rash and sometimes arthralgias due to a Type III hypersensitivity (immune complex deposition), no vaccine available

B19

7

How does B19 infect and in which patients can this be a serious issue?

Infects immature erythroid progenitor cells, which results in cell lysis. Usually asymptomatic but in patients with sickle cell, can cause aplastic crisis.

8

dsDNA, naked icosahedral, many serotypes, infects basal layer of skin and mucous membranes and causes a hyperkeratosis, associated with warts and condylomata acuminata, some serotypes are premalignant (cervical intraepithelial neoplasia)

Human papilloma virus

9

koilocytic cells on Pap smear

Human papilloma virus
Serotypes 6 and 11 = benign, more common
Serotypes 16, 18, 31, 35 are preneoplastic; genes E6 and E7 inhibits p53 and Rb

Gardasil recombinant vaccine covers 6, 11, 16, 18

10

Polyomavirus, causes renal disease in AIDS patients

BK Virus

11

Polyomavirus, infects oligodendrocytes and causes demyelination, causes progressive multifocal leukoencephalopathy in AIDS or transplant patients

JC Virus

Also on differential: subacute sclerosing panencephalitis, prions

12

dsDNA, nonenveloped, many serotypes, penton fibers act as hemagglutinin and are also directly toxic to cells, virus is lytic in permissive cells and can be transformative/oncogenic in nonpermissive cells, causes pneumonia in military, pharyngoconjunctivitis in kids at swimming pools

Adenovirus

13

10 yo boy presents with painful urinating and blood in urine. He has no other symptoms and does not have a history of a recent illness.

Acute hemorrhagic cystitis, caused by adenovirus. Differentiate from Post-strep glomerulonephritis which is much more serious

14

What kind of vaccine is available for adenovirus?

Enteric coated live, nonattenuated vaccine used in the military

15

dsDNA, enveloped icosahedral, contains intranuclear inclusion bodies, establishes latency in nerves

Herpesviridae (HSV 1 and 2, VZV, EBV, CMV, HHV6, HHV8)

16

Cause of gingivostomatitis, cold sores, keratoconjunctivitis

HSV1, establishes latency in trigeminal ganglion

17

Fever, headache, confusion, focal temporal lesions, perivascular cuffing, high mortality rate if untreated, leading cause of viral encephalitis in US

HSV1

18

Cause of genital infections, severe neonatal infection during passage through birth canal

HSV2, establishes latency in sacral ganglion

19

Diagnosis of herpes genital infections?

Tzank smear to show multinucleated giant cells and Cowdry Type A intranuclear inclusions

20

Causative agent chickenpox and shingles, dewdrops on rose petals, latency in dorsal root ganglion, live attenuated vaccine available with boosters, diagnose with Tzanck smear

Varicella Zoster Virus

21

How can you differentiate a chickenpox rash from a smallpox rash?

Chickenpox: asynchronous (macules, vesicles, and scabs will all be present at same time)

Smallpox: synchronous (rash will be in same stage)

22

Latent infection of B cells by binding to CD21 and produces atypical reactive T cells (known as Downey Type II cells)

Epstein-Barr Virus

23

Malignancies associated with EBV

Burkitt lymphoma (c-myc), nasopharyngeal carcinoma, Hodgkin lymphoma

24

Diagnosis of EBV

heterophile antibody positive (IgM), serology (EBNA associated with transformed cells)

25

Two presentations of EBV infection in immunocompromised patients

lymphoproliferative disease, hairy oral leukoplakia

26

Most common in utero infection in the US

Cytomegalovirus

27

Infection of salivary gland epithelial cells and establishment of an infection in fibroblasts, epithelial cells, and macrophages which becomes latent in mononuclear cells

CMV

28

Cause of heterophile negative mononucleosis, blueberry muffin baby in utero, or intersitial pneumonitis/retinitis in AIDS patients

CMV

29

Owl eye inclusion bodies

CMV

30

Child has extremely high fever (high enough to induce seizures) for 3-5 days which resolves and is followed by a lacy body rash

Roseola, caused by HHV6

31

Causes sarcoma in AIDS patients by turning on VEGF

Kaposi sarcoma

32

Large dsDNA, enveloped, replicates in cytoplasm, potential for biowarfare, 1 serotype, transmitted via inhalation, disease consists of prodrome followed by synchronous rash

Variola/Smallpox

The single serotype has allowed for 100% eradication (still potential for biowarfare agent, especially since we have stopped vaccinating)

33

Virus used for smallpox vaccine

Vaccinia

34

Intracytoplasmic assembly of smallpox virus in cytoplasm

Guarnieri bodies

35

Member of poxviridae, transmitted by direct contact or fomites, replicates in dermis, disease in young adults of benign wart like umbilicated tumors that are self limiting in immune competant individual

Molluscum contagiosum