HPV Flashcards
What is the pathophysiology of HPV?
Virus infects superficial layer of epidermis –> proliferation of skin cells (keratinocytes) and hyperkeratosis –> warts
Virus likely to be widespread on skin surface around wart –> trauma in surrounding area –> inoculate wart virus –> new lesions develop
What HPV types cause cutaneous warts?
The following types:
2, 3, 4
10, 27, 29
57
What HPV types cause anogenital warts?
Types 16 and 18 = 80% of cervical cancers in women, 90% of HPV-related cancers in men
Types 6 and 11 = 95% of genital warts
What is verruca vulgaris? (features/characteristics, location?)
Common wart
Found on = fingers, hands, knees, toes
Characteristics/features = hyperkeratotic, dome shaped papules/plaques w/ central black dots that are thrombosed (clotted) capillaries
What is verruca plantaris? (features/characteristics, location?)
Plantar warts
Found on = sole of foot in weight bearing and non-weight bearing areas
Characteristics = tender, inward growing (so appear flat) lesions, can be painful
What is verruca planus? (features/characteristics, location?)
Plane warts
Characteristics = small and slightly raised, although can have flat surface —> develop in clusters
Found on = face, back of hands, and shins
What is filiform warts? (features/characteristics, location?)
Characteristics = Long and slender, sometimes described as digitate (looking like fingers)
Found = face
What is condyloma acuminata? (features/characteristics, location?)
Genital warts, venereal warts
Characteristics = flesh colours, small papules. May cluster to form larger cauliflower like lesion
Found on = vulva, vagina, cervix, urethra, penis, scrotum, anus
What are some differential diagnoses for warts?
Molluscum contagiosum = pox virus –> firm, smooth, pearly pink papules w/ keratin plug
- head, neck, trunk
- associated w/ inflammatory reaction (e.g. eczema)
- *common warts are not smooth
Callus or corn = may resemble plantar wort but corn only found in pressured areas (plantar wart can be anywhere).
- callus/corn will lack central black dot
Skin cancer = BCC or SCC – may be difficult to differentiate
- refer if suspicious = irregular outline, bleeds, changes colour or shape
List the main treatments for cutaneous warts
Most tx relies on tissue destruction or immune modification (can scar) –> some resolve spontaneously
- aggressive treatment may be inappropriate for children
Salicylic acid
Podophyllum resin
How is salicylic acid used to treat warts?
1st line = safe and inexpensive
Forms can be combined w/ - lactic acids (not more affective than salicylic acid alone), trichloroacetic acid, and podophyllum resin
How is podophyllum resin used to treat warts?
Can be extemporaneously prepared as paint, combinations w/ salicylic acid are available
Evidence is lacking and close supervision is required due to risk of systemic toxicity
List the main tx for anogenital warts
No specific HPV tx available, current tx relies on tissue destruction
- goal = eliminate physical or psychological sx
- tx can be self applied or treated by GP in surgery
Podophyllotoxin
Imiquimod
Outline some alternative treatments for warts
Cryotherapy = Freezing the wart (cutaneous or anogenital warts), multiple sessions required and may cause pain and scarring
Ablative therapy = no distinct advantage, may be costly
- electrosurgery and curettage --> burning wart off w/ low voltage electric probe - Blunt dissection = separate tissue w/ blunt instrument as apposed to sharp tool - laser therapy = intense light beam to burn and destroy wart tissue
How is podophyllotoxin used to treat anogenital warts? (how often applied?)
More effective than podophyllum resin for anogenital warts, low systemic toxicity
No need to wash after application, considered 1st line for self-treatment
Apply bd for 3 days, then no treatment for 4 days –> can repeat cycle for up to 4-5 cycles
