Genital warts (condyloma acuminatum) are the clinical manifestations of a sexually transmitted disease caused by some types of human papillomavirus (HPV).
HPV is transmitted primarily through penetrative sex. While HPV also can be transmitted via non-penetrative sexual activity, it is less common.
Genital HPV infections have an estimated prevalence of 10% to 20% with clinical manifestations in 1%. The incidence of HPV infection has been increasing. About 80% of those infected are between the ages of 17 and 33 years, with the peak age group being 20 to 24. It has been estmated that 2.9% of the US male population will have genital HPV DNA.
Although treatments can remove warts, they do not remove the HPV. Warts may sometimes spontaneously regress. Traditional theories postulate that the virus remains in the body for a lifetime. However, it is now believed that the virus may be either cleared or suppressed to levels below what polymerase chain reaction (PCR) tests can measure.
HPV infection appears to be the cause of most cases of anal cancer (about 90%) and virtually all cases of cervical cancer in women, with HPV type 16 accounting for about 50% of these. (Cervical cancer is the fourth most common cancer in women.) Some vulvar cancers have been linked to HPV infections (29% to 43%), while vaginal cancer is associated with HPV infections about 70% of the time (HPV Types 16 and 18).
In men, Bowen disease of the penis and about 35% to 40% of all penile cancers are associated with HPV infections.
Risk factors for HPV persistence include age, smoking, immunosuppression, and simultaneous infection with multiple HPV types.
Genital warts tare typically diagnosed visually with confirmatory biopsy generally unnecessary. These exophytic lesions form due to enlargement of the dermal papillae and are lined by hyperplastic squamous epithelium that shows koilocytes, which are squamous epithelial cells characterized by an acentric, hyperchromatic nucleus displaced by a large perinuclear vacuole.
Genital warts may occur separately or in clusters. They may be found in the anal or genital area, including the penile shaft, scrotum, vagina, or labia majora. They also can be found on internal surfaces of the vagina and the anus.
They can be small (5 mm or less in diameter) or spread into large masses in the genital or anal area. Their color is variable but tends to be skin colored or darker, and they may occasionally bleed.
Sometimes warts may cause itching, redness, or discomfort. An outbreak of genital warts may also cause psychological distress.
In most cases, the only identifiable symptoms of an HPV infection are warts.
The diagnosis of genital warts is usually made visually although a biopsy may be necessary for confirmation. Small warts may sometimes be confused with molluscum contagiosum. Genital warts typically rise above the skin surface, have parakeratosis, and demonstrate nuclear changes typical of HPV infections (nuclear enlargement with perinuclear clearing). Because genital warts are caused by low-risk HPV types, DNA tests should not be used for diagnosis or in low-risk HPV infections.
Some practitioners use an acetic acid solution to help identify small warts and affected skin areas, but this practice is controversial.
A biopsy is recommended if there is uncertainty about the diagnosis or if the patient is immunocompromised. Pigmented and ulcerated lesions should also be considered for biopsy.
Cystoscopy should be considered in patients where the glans is involved, the patient has lower urinary tract symptoms, or there are significant urethral symptoms. In patients who have no symptoms, some experts have suggested waiting until any glans lesions have healed to avoid possible transfer of HPV virus into the urethra.
There is no cure for HPV. Removing visible warts does not reduce transmission of the underlying HPV infection. About 80% of individuals with HPV will clear the infection spontaneously within 18 to 24 months.
Treatment varies depending on the number, size, and location of warts. Treatment can cause permanent depigmentation, itching, pain, and scarring.
Urethral meatus warts are best treated with surgery to minimize long-term complications.
The American Urological Association does not recommend treating sub-clinical (invisible) lesions.
Treatments are either ablative (vaporization, resection, coagulation, or excision) or involve the use of topical agents. Physically ablative treatments are more effective at wart removal, but in many cases, topical agents are preferred by patients as an initial therapy, especially for smaller lesions.
Physical Removal or Destruction
Direct excision or physically destructive therapies are considered more effective on keratinized warts, especially if they are larger in size.
Topical agents may be very effective and are less traumatic than surgical intervention.
Gardasil is a vaccine used to protect against human papillomavirus types 6, 11, 16, and 18. Types 16 and 18 cause an estimated 70% of cervical cancers, and 6 and 11 cause an estimated 90% of genital warts. The vaccine prevents the disease but is not therapeutic. The vaccine must be given before exposure to the virus type to be effective. The vaccine was approved by the United States Food and Drug Administration (FDA) in 2006 for use in children as early as nine years of age, primarily for its prophylactic activity against cervical cancer. Gardasil 9 was FDA approved in 2014 to protect against the four HPV strains covered by the first generation of Gardasil as well as five other HPV strains responsible for 20% of cervical cancers (HPV-31, HPV-33, HPV-45, HPV-52, and HPV-58).
Vaccines are preventative and should not be considered therapeutic. Quadrivalent or 9-valent vaccines are recommended and generally preferred over bivalent vaccines.
According to the Advisory Committee for Immunization Practices (ACIP), routine HPV vaccination is recommended for women 9 to 26 years of age, but it has shown high efficacy up to age 45.
The ACIP recommends routine male HPV quadrivalent vaccinations at age 11-12. If not previously given or incomplete (the vaccines are a three-dose series), the vaccine should be given up to age 21. From age 22 to 26, the vaccine is considered optional. In other words, the optimal age for male HPV vaccination is 11 to 12 years, but it may be given up to age 26 years.
It remains to be seen if the more extensive use of vaccines can reduce the prevalence and penetration of HPV exposure, infections and complications.