Ano-Genital Warts

Definition/diagnostic criteria Ano-genital warts, also known as condylomata acuminata, are a common sexually transmitted infection (STI) caused predominantly by human papillomavirus (HPV) types 6 and 11. They manifest as painless, skin-coloured growths in the ano-genital region. Diagnosis is clinical, based on the presence of characteristic lesions.

Epidemiology These warts represent one of the most common viral STIs in the UK, particularly affecting the 15-24 age group. The spread is primarily via sexual contact, with the risk increased in those with multiple sexual partners and in those not using barrier contraception.

Diagnosis Clinical Features: The warts are often soft, skin-coloured, cauliflower-like, and may be single or multiple. They appear on the penile shaft, labia, vagina, cervix, or around the anus. Symptoms can include discomfort or itching, but many cases are asymptomatic.

Investigations: Diagnosis is typically clinical. In uncertain cases, biopsy showing koilocytosis confirms the diagnosis. HPV DNA testing is reserved for atypical presentations.

HPV and Cervical Cancer While ano-genital warts are usually caused by low-risk HPV types, high-risk types (notably 16 and 18) are associated with cervical cancer. In the UK, HPV testing is used in cervical screening, with cytology being performed in those who are HPV positive. If cytology is negative, the patient is rescreened a year later; if positive they are referred for colposcopy.  HPV vaccination, which protects against key cancer-causing strains of HPV, is also part of the UK’s immunization program.

Treatment

1. Topical Treatments: Imiquimod cream, podophyllotoxin solution or cream, and sinecatechins ointment. These are patient-applied and recommended for small, non-keratinized warts.
2. Physical Ablative Techniques: Cryotherapy, surgical excision, electrocautery, or laser therapy, typically administered by a healthcare professional. Suitable for external and larger warts.
3. Referral: Referral to a specialist is advised for complicated cases, such as immunocompromised patients, extensive warts, or warts unresponsive to initial treatment.

Treatment choice depends on factors like wart size, number, site, patient preference, and cost. Patient education on the application of topical treatments is crucial. It’s important to note that while treatment can remove visible warts, it does not eradicate HPV, so recurrence is possible. It’s important that screening is also performed for other STIs.

Prognosis The prognosis is generally favourable, with treatments effectively clearing warts in most cases. However, recurrence is common within a few months. Most HPV infections are cleared by the immune system within two years.