Anogenital warts Flashcards
What organism causes anogenital warts?
Human papilloma virus (HPV)
How many genotypes of HPV are there?
over 100
What are the typical HPV genotypes in anogenital warts?
6 & 11
What percentage of anogenital warts are due to HPV 6 or 11?
90%
What genotype of HPV cause hand warts?
HPV type 2
Can HPV type 2 occur on the genitals?
Reported cases in children of HPV 2 transferred from hands to genitals
Can HPV infection occur through contact with fomites?
No
Oncogenic HPV is most common to be found in what lesions?
Anogenital dysplastic lesions
Cancer
Most HPV infection does not result in visible lesions, how quick does infection resolve?
Resolve spontaneously within a year
HPV bi-valent vaccine - against which HPV types?
High risk types 16 & 18
HPV quadrivalent vaccine - against which HPV types?
6/11/16/18
Anogenital warts - describe their typical presentation
Benign epithelial skin tumours Single or multiple Soft and non-keratinised on moist, non-hair bearing skin Firm and keratinised on dry hairy skin Broad based or pedunculated sometimes pigmented
Where are HPV lesions most likely to arise?
Site of trauma during sexual intercourse
Who more commonly get perianal HPV lesions?
Men who have sex with men
Common in BOTH sexes and not necessarily associated with anal sex
If warts occur inside anal canal what is this associated with?
Penetrative anal sex
Where do extra genital HPV lesions occur?
Oral cavity
Larynx
Conjunctivae
Nasal cavity
What are the symptoms of anogenital warts?
Asymptomatic Lumps/growths local irritation bleeding discomfort secondary infection or maceration
What is the incubation period of HPV?
3 weeks to 8 months, but can be up to 18 months
What is the most common appearance of a genital wart?
Soft, cauliflower-like growths of varying size
Rarely a wart may grow rapidly and infiltrate local tissue/local erosion, what are they called?
Buschke-lowenstein lesion
When should biopsy of the HPV-type lesion be considered?
If do not respond to treatment
When should proctoscopy be performed for HPV disease?
Unable to visualise upper limit of warts
Irritation, bleeding or rectal discharge
How effective are condoms at reducing risk of HPV acquisition?
30-60% reduction
What patient specific factors may mean they respond poorly to treatment for HPV lesions?
Current Smoker
Soft, non keratinised warts respond well to which treatments?
Podophyllotoxin
Trichloracetic acid
Keratinised warts may require what alternative treatments?
Cryotherapy
Excision
For what type of warts can imiquimod be used?
BOTH keratinised and non-keratinised
If there is only a small number of warts what is the best first line therapy?
Cryotherapy
or
Podophyllotoxin
What proportion of warts will clear spontaneously within 6 months?
30%
HPV treatment - podophyllotoxin - regimen?
0.5% solution OR 0.15% cream twice daily 3 days, rest 4 days
Similar efficacy
Cream easier to apply
Often used on all anogenital sites, licensed for external genitalia
Imiquimod - mechanism of action
immune response modifier
acts as a toll-like receptor-7 (TLR7) agonist
stimulation of local tissue macrophages to release interferon-alpha and other cytokines part of a local cell-mediated response
HPV treatment - imiquimod - regimen?
5% cream
apply 3 times weekly, wash off 10 hours later
Trial up to 16 weeks, can extend if working
What is catephen?
extract of the leaf of the green tea plant Camellia sinensis
containing epigallocatechingallate
HPV treatment - catephen - regimen?
10% ointment 3 times a day
Trial up to 16 weeks
Trichloroacetic acid (TCA) - mechanism of action
caustic agent resulting in cellular necrosis
When can TCA be used for treatment of genital warts?
in specialistic clinic, not for self application
HPV treatment - TCA - regimen?
80-90%
Weekly application
How may surrounding skin be protected when using TCA?
Petroleum jelly
+
neutralising agent (sodium bicarbonate) in event of excess application
When using liquid nitrogen to treat HPV how should this be performed?
Apply until a ‘halo’ of freezing established
Single freeze or a double freeze
Aim 15-30 seconds of freezing
What is the main limiting factor to cryotherapy?
Patient tolerability
How often should cryotherapy be repeated for anogenital warts?
Weekly
Review at 4 weeks if no improvement
What are the 3 types of electrosurgery?
Electrocautery
Hyfrecation
Monopolar surgery
HPV excision - describe electrocautery
burning of the treatment site and surrounding tissue
HPV excision - describe hyfrecation
electrofulguration resulting in superficial charring and limited dermal damage
can be followed by curettage
HPV excision - describe monopolar surgery
different waveforms can be generated, allowing desiccation, cutting, or coagulation
cleaner cut and less damage to surrounding tissue
When might laser treatment be considered for anogenital warts?
Large volume warts
What is the main limitation to laser treatment for HPV?
Expensive
What treatment can be offered for intravaginal warts?
Cryotherapy Electrosurgery TCA or Podophyllotoxin off license
What treatment can be offered for urethral meatus warts?
If base of wart can be seen: cryotherapy electrosurgery laser ablation podophyllotoxin Imiquimod
When should urethral meatal warts be referred to urology?
If unable to see base of wart
What treatment can be offered for intra-anal warts?
cryotherapy
topical Imiquimod (unlicensed indication) electrosurgery
laser ablation
trichloroacetic acid
What treatment should be avoided in pregnancy?
Podphyllotoxin
Imiquimod
5-FU
