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The human papilloma viruses (HPV) are nonenveloped, double-stranded DNA viruses that belong to the family Papovaviridae. There are over 80 subtypes of HPV causing a wide spectrum of cutaneous manifestations, the most common being verrucae. Verrucae may resemble seborrheic keratoses, nevi, or acrochordons. In these cases, similar treatments may be chosen. However, verrucae planae may sometimes mimic papules of lichen planus, and condyloma acuminatum must be differentiated from condyloma lata; the diagnosis must be carefully established, because the appropriate therapies are human papilloma virus.
Once benign verrucae are diagnosed, the objective is to eradicate the lesion and allow the immune system to hold latent HPV in surrounding normal appearing skin in check, thus preventing recurrences. Several different modalities have been used, including surgery, simple excision, electrodesiccation, and removal with a CO2 laser. Cryotherapy with liquid nitrogen is also used to destroy the lesion. Topical chemotherapy with podophyllin resin, purified podophyllotoxin, 5-fluorouracil, retinoic acid, cantharidin, salicylic acid, lactic acid, bichloroacetic acid (dichloroacetic acid), and trichloroacetic acid.
Until recently, interferon (IFN)-alpha was the only antiviral therapy approved for HPV in the clinical presentation of condyloma acuminatum. IFN-alpha is also approved by the United States Food and Drug Administration (FDA) for treatment of hepatitis B and C, hairy cell leukemia, and Kaposi's sarcoma in AIDS patients, and for post-surgical therapy of malignant melanoma; however, condyloma acuminatum is the most prevalent viral infection for which IFN-alpha is FDA approved. IFN-alpha exerts many effects on cell proliferation and differentiation as well as on immune regulation and on oncogene and anti-oncogene expression, which do not necessarily involve a virus. IFN-alpha, used alone, can eradicate up to 50% to 70% of visible warts. However, IFN-alpha used in combination with cytodestructive or surgical therapy.
Because exogenous IFN-alpha must be given via injection and is associated with a flu-like syndrome, stimulation of endogenous IFN-alpha has been developed as a much more "user friendly" treatment of HPV. Imiquimod, an immunomodulatory heterocyclic amine, stimulates human peripheral blood mononuclear cells to release various subtypes of IFN-alpha as well as to produce and release a variety of other cytokines, such as tumor necrosis factor (TNF) and interleukin (IL) 1, 6, 8, 10, and 12 as well as IL-1 receptor antagonist. Thus, imiquimod induces endogenous cytokine production.
New treatments for HPV-related lesions currently under study include antisense oligonucleotides, which have not yet been proven effective for HPV lesions. Cidofovir is a nucleotide analog with a broad spectrum of activity against a variety of DNA viruses; it has been proven effective as a 3% gel in the treatment of.... Controlled trials with recombinant HPV protein vaccines.