Case 28: HPV

Question 1

what is the clinical presentation of HPV in a female?

Answer 1

1. small, raised lesions on the cervix
2. labial venereal warts
3. friable, erythematous cervix

blood labs should be fine

Question 2

what diagnostic workup should you do if you suspect HPV?

Answer 2

1. Pap smear is necessary but it’s not sufficient since there’s 50% false negative
2. DNA hybridization of biopsy for HPV
3. ELISA assay to detect HPV-specific IgG antibody

Question 3

what are the characteristics of the HPV virion?

Answer 3

• naked viruses of icosahedral symmetry

- double-stranded circular DNA

Question 4

do HPV viruses grow in cell cultures?

Answer 4

nope

so you have to test them using molecularly cloned HPV DNA of a known type as a standard

Question 5

which HPV strains cause common warts on nongenital tissue?

Answer 5

1,2,4,26,27,29

Question 6

which HPV strains cause plantar warts on nongenital skin?

Answer 6

1,2,4,63

Question 7

which HPV strains cause epidermodysplasia verruciformis?

Answer 7

3,10, 27, 38

Question 8

which HPV strains cause skin cancers in transplan recipients?

Answer 8

48, 60

Question 9

which HPV strains cause anogenital warts?

Answer 9

6 and 11

Question 10

which HPV strains cause dysplasias and cancer?

Answer 10

16, 18, 31, 33 and 35

Question 11

how is HPV spread?

Answer 11

the types of HPV that infect the genital

area are spread primarily through genital contact

Question 12

do HPV infections have symptoms?

Answer 12

not really

most HPV infections have no
signs or symptoms; therefore, most infected persons are unaware they are infected

they can still transmit the virus to a sex partner

Question 13

what are the risk factors for HPV infection leading to

carcinoma of the cervix?

Answer 13

• sex before 15
• multiple partners
• exposure to other STDs
• mother/sister with cervical cancer
• smoking
• immunosuppression
• HIV/AIDS
• chronic corticosteroid use

Question 14

what is the pathology of HPV?

Answer 14

HPVs infect the squamous epithelial cells of the basal layer of the skin or mucous
membrane

they enter basal cells that have been exposed through a disturbed epithelial
barrier, as would occur during sexual intercourse

Question 15

where does HPV replicate?

Answer 15

nucleus

consequently, They enter basal cells that have been exposed through a disturbed epithelial
barrier, as would occur during sexual intercourse. like perinuclear clearing (halo) or a shrunken nucleus

sometimes in low-risk HPV strains, the HPV genome exists as a circular, episomal DNA separate from
the host cell nucleus – the infection is characterized by proliferation and thickening of
the basal layer, leading to the appearance of a wart

Question 16

how do you treat HPV?

Answer 16

the goal is to remove symptomatic warts

whether or not removing the warts actuall decreases transmission is unknown

also no evidence indicates that the presence of genital warts or their treatment is associated with the development of cervical cancer

Question 17

which HPV strains cause cervical cancer?

Answer 17

16 & 18

these cause carcinoma of the cervix!

HPV strains that cause genital warts aren’t the same as the HPV strains that cause cancer

Question 18

how do HPV 16 & 18 cause cervical cancer?

Answer 18

HPV types 16 and 18 typically are integrated into the host cell DNA

integration of
the viral genome into the host cell genome is considered a hallmark of malignant transformation

HPV proteins E6 and
E7 of HPV types 16 and 18 inactivate the host’s tumor suppressor proteins p53 and retinoblastoma (Rb) and subvert the
cell growth regulatory pathways

they modify the cellular environment in order to facilitate viral replication in a cell
that is terminally differentiated and has exited the cell cycle

the result is an unregulated epithelial growth, which
begins at the basal layer and extends outward (dysplasia) and may progress to invasive squamous cell carcinoma

Question 19

how do you prevent HPV?

Answer 19

condoms

regular Pap smears to screen for cervical cancer