Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content + Download Section PDF Listen ++ For further information, see CMDT Part 6-36: Warts + Key Features Download Section PDF Listen +++ +++ Essentials of Diagnosis ++ Verrucous papules anywhere on the skin or mucous membranes, usually < 1 cm in diameter Prolonged incubation period (average 2–18 months); spontaneous "cures" (50% at 2 years for common warts) "Recurrences" (new lesions) are frequent +++ General Considerations ++ Caused by human papillomaviruses (HPVs) Typing of HPV lesions is not a part of standard medical evaluation except in the case of genital dysplasia Genital HPVs are divided into low-risk and high-risk types depending on the likelihood of their association with cervical and anal cancer + Clinical Findings Download Section PDF Listen +++ +++ Symptoms and Signs ++ There are usually no symptoms Tenderness on pressure occurs with plantar warts; itching occurs with anogenital warts Flat warts are most evident under oblique illumination Periungual warts may be dry, fissured, and hyperkeratotic and may resemble hangnails or other nonspecific changes Plantar warts resemble plantar corns or calluses +++ Differential Diagnosis ++ Seborrheic keratosis Hypertrophic actinic keratoses Squamous cell carcinomas Condylomata lata of secondary syphilis Molluscum contagiosum Varicella zoster (in AIDS) + Diagnosis Download Section PDF Listen +++ ++ Clinical Biopsy may be necessary for definitive diagnosis + Treatment Download Section PDF Listen +++ +++ Medications +++ For Nongenital Warts ++ Liquid nitrogen Apply to achieve a thaw time of 30–45 seconds Two freeze-thaw cycles are given every 2–4 weeks for several visits Scarring will occur if it is used incorrectly May cause permanent depigmentation in darkly pigmented individuals Keratolytic agents and occlusion Salicylic acid products may be used against common warts or plantar warts They are applied, then occluded Plantar warts may be treated by applying a 40% salicylic acid plaster after paring The plaster may be left on for 5–6 days, then removed, the lesion pared down, and another plaster applied Although it may take weeks or months to eradicate the wart, the method is safe and effective with almost no side effects Chronic occlusion alone with water-impermeable tape (duct tape, adhesive tape) is less effective than cryotherapy Podophyllin Ineffective for common warts and plantar warts Contraindicated in pregnant women Imiquimod should not be used to treat plantar or common warts Immunotherapy Squaric acid dibutylester may be applied in a concentration of 0.2–2% directly to the warts from once weekly to five times weekly to induce a mild contact dermatitis Between 60% and 80% of warts clear over 10–20 weeks Injection of Candida antigen starting at 1:50 dilution and repeated every 3–4 weeks may be similarly effective in stimulating immunologic regression of common and plantar warts Bleomycin Dosage: diluted to 1 unit/mL, injected into common and plantar warts Should be used with caution on digital warts because of the potential complications of Raynaud phenomenon, nail loss, and terminal digital necrosis 5-Fluorouracil 5% cream applied once or twice daily, usually with occlusion, may be applied to warts with the similar efficacy to other treatment methods Laser therapy Can be used for recurrent warts, periungual warts, plantar warts, and genital warts Should be reserved for refractory cases Leaves open wounds that must fill in with granulation tissue over 4–6 weeks and is best reserved for warts resistant to other modalities Photodynamic therapy can be considered in refractory widespread flat warts +++ For Genital Warts ++ Liquid nitrogen First-line clinician-applied surgical treatment for genital warts Applied to achieve a thaw time of 30–45 seconds Two freeze-thaw cycles are given every 2–4 weeks for several visits Scarring will occur if it is used incorrectly May cause permanent depigmentation in pigmented individuals Podophyllum resin The purified active component of the podophyllum resin, podofilox, is applied by the patient twice daily for 3 consecutive days a week for cycles of 4–6 weeks It is less irritating and more effective than "clinician-applied" podophyllum resin However, recurrence is common after discontinuation, making multiple cycles necessary Imiquimod A 5% cream of this local interferon inducer has moderate activity in clearing external genital warts Dosage: once daily on 3 alternate days per week Response may be slow, with patients who eventually cleared having responses at 8 weeks (44%) or 12 weeks (69%) Once cleared, about 13% have recurrences in the short term In women, Imiquimod has high rate of response Safety profile make it treatment of choice despite its expense In men, Podophyllotoxin is the initial treatment of choice because of more rapid response, lower cost, and similar efficacy compared with imiquimod However, imiquimod should be used for recurrences or refractory cases Laser therapy: For genital warts, it has not been shown that laser therapy is more effective than electrosurgical removal. Photodynamic therapy can be considered in refractory genital warts +++ Therapeutic Procedures ++ Soaking warts in hot (42.2°C) water for 10–30 min daily for 6 weeks can result in involution +++ OPERATIVE REMOVAL ++ Plantar warts may be removed by blunt dissection For pedunculated or large genital warts, snip biopsy (scissors) removal followed by light electrocautery is more effective than cryotherapy + Outcome Download Section PDF Listen +++ +++ Prognosis ++ Development of new lesions is common Warts may disappear spontaneously or may be unresponsive to treatment Combining therapies (eg, liquid nitrogen plus immunotherapy) may improve therapeutic response +++ Prevention ++ The use of condoms may reduce transmission of genital warts Administration of a vaccine against certain genital HPV types can prevent infection and reduce cervical dysplasia; it is recommended for teenagers and young adults +++ When to Refer ++ If there is a question about the diagnosis, if recommended therapy is ineffective, or if specialized treatment is necessary + References Download Section PDF Listen +++ + +Aldahan AS et al. Efficacy of intralesional immunotherapy for the treatment of warts: a review of the literature. Dermatol Ther. 2016 May;29(3):197–207. [PubMed: 26991521] + +Alikhan A et al. Use of Candida antigen injections for the treatment of verruca vulgaris: a two-year Mayo Clinic experience. J Dermatolog Treat. 2016 Aug;27(4):355–8. [PubMed: 26558635] + +Bertolotti A et al. Cryotherapy to treat anogenital warts in non-immunocompromised adults: systematic review and meta-analysis. J Am Acad Dermatol. 2017 Sep;77(3):518–26. [PubMed: 28651824] + +O'Mahony C et al. Position statement for the diagnosis and management of anogenital warts. J Eur Acad Dermatol Venereol. 2019 Jun;33(6):1006–19. [PubMed: 30968980] + +Veitch D et al. Pulsed dye laser therapy in the treatment of warts: a review of the literature. Dermatol Surg. 2017 Apr;43(4):485–93. [PubMed: 28272080]