Resident Editor: Lily Kornbluth, M.D.
Faculty Editor: ***
Intro and Background
- HPV causes both cutaneous and anogenital warts.
- Quadrivalent HPV vaccine >80% effective if given before HPV 6 and 11 exposure
- Average reported cure rate for cutaneous warts is 30% in 10 weeks
- Warts are particularly common in immunosuppressed patients (90% of renal transplant patients have warts after 5 years)
- Genital warts are present in 1% of sexually active US adults
- Consider the differential diagnosis for anogenital warts
- Condyloma lata, manifestation of secondary syphilis (tend to be smooth, moist, and flat). Treated with IM penicillin.
- SCC. Needs biopsy, treated with excision
- Vulvar intraepithelial neoplasia. Considered to be a precancerous lesion. Needs biopsy, various treatment modalities.
- Other: epidermoid cysts, Fordyce spots, granuloma annulare, lichen planus, molluscum, pearly penile papules, seborrheic keratosis
Indications
- Watchful waiting is an option for new warts
- Cutaneous warts – ½ resolve in 1 year and ¾ resolve in 2 years
- Anogenital warts – 1/3 spontaneously resolve
- There are no clear guidelines for referral to anal dysplasia clinic, however, consider referring all MSM (regardless of HIV-status) and all HIV-positive men and women and other immunosuppressed patients with anal lesions for evaluation, given the higher risk these populations have of developing squamous cell carcinoma of the anus.
Treatment Options
Nongenital cutaneous warts
- First line:
- Watchful waiting
- Salicylic acid (73% cure rate with 6-12 wks treatment)
- Cryotherapy (50-70% cure rate after 3-4 treatments)
- Refractory warts
- Referral to dermatology for consideration of: topical 5-FU, intralesional Candida, surgical removal, photodynamic therapy, laser, intralesional bleomycin, and other second- and third-line therapies
Genital warts
- First line:
- Patient applied: Imiquimod (Aldara), Podophyllotoxin (Condylox), Sinecatechins (Veregen). Cost can be prohibitive with these topicals.
- Clinician applied: cryotherapy
- Referral to dermatology for consideration of: electrosurgery, TCA application, excision, laser
Cryotherapy technique
- Spray or apply liquid nitrogen onto the wart until the wart and 1-2mm of surrounding tissue turns white.
- Allow area to return to normal skin color and repeat freeze-thaw cycle 2-3 times total
- Aggressive cryotherapy (10-30s each cycle) is more effective than less aggressive cryotherapy
- Treat every 2-3 weeks. No benefit beyond 3 months of treatment
- If the skin is thick (ie plantar warts), pare the wart first
- Advise patients to also apply salicylic acid treatments at home in between cryotherapy treatments
- Patients may experience hypo- or hyper-pigmentation of the skin.
Salicylic acid technique for nongenital cutaneous warts
- soak wart in warm water and then gently file down with emery board or pumice stone
- apply any OTC salicylic acid product (most common 17%)
- repeat daily or per product instructions
- treat for up to 12 weeks
References
Mulhem I, Pinelis S. Treatment of Nongenital Cutaneous Warts. Am Fam Physician. 2011 Aug 1;84(3):288-293.
Karnes J, Usatine R. Management of External Genital Warts. Am Fam Physician. 2014;90(5):312-318.
Goldsmith LA, Katz SI, Gilchrest BA, Paller AS, Leffell DJ, Wolff K. eds. Fitzpatrick's Dermatology in General Medicine, 8e New York, NY: McGraw-Hill; 2012. http://accessmedicine.mhmedical.com/content.aspx?bookid=392§ionid=41138687. Accessed March 26, 2018.