Editorials

The management of anal warts

Topical self treatment, ablative therapy, and counselling should all be available

The incidence of condylomata acuminata, commonly known as anogenital warts, is increasing. In the United Kingdom it is the most common sexually transmitted disease; in 1997 over 50 000 new cases were reported, accounting for 22% of all diagnoses made in genitourinary medicine clinics.¹ In the United States an estimated 1% of adults who are sexually active have lesions.² These benign warts are caused by human papillomavirus; genotypes 6 and 11 are found in over 90% of cases.³ However, some patients are concurrently infected with oncogenic types of the virus, principally genotypes 16 and 18, which may induce multifocal anogenital intraepithelial neoplasia and cervical cancer.⁴ Although people with anogenital warts present to many different disciplines guidelines for management have recently been published by the Medical Society for the Study of Venereal Diseases of the United Kingdom and the European Course on Human Papilloma Virus Associated Pathology Group. ^{5 6}

These guidelines conform to recommendations as for a Cochrane review and focus on sharing management between specialists and primary care physicians.⁷ No specific treatment and no one therapeutic recipe is appropriate for all patients. Although most modalities will achieve clearance of the virus within 1-6 months, in 20-30% of patients new lesions and relapses will occur over months or even years as a result of failures in specific immune recognition and cell mediated clearance.⁸ This is a highly frustrating experience for patients and caregivers.

There has been a shift in the focus of treatment towards topical self treatment for patients, using agents such as podophyllotoxin (0.5% solution or 0.15% cream) and imiquimod (5% cream). Clearance rates seem to be equivalent for the two drugs. In many patients imiquimod, which modifies the immune response, may induce the necessary cell mediated immune response for clearance, and it has a low relapse rate.⁹ But imiquimod costs more than podophyllotoxin and takes longer to cure the condition. A study is needed to directly compare imiquimod with podophyllotoxin to address issues of comparative effectiveness, cost, and psychosexual advantages.

Podophyllin, 5-fluorouracil, and interferons are no longer recommended for use in primary care because of their low efficacy and toxicity. ^{5 6} Podophyllin 20-25% is inexpensive, but it is mutagenic and only moderately efficacious.¹⁰ Recommended treatments that can be used in the doctor's office include trichloroacetic acid or physical ablation using cryotherapy, electrosurgery, excision, or laser treatment. ^{5 6}

Clinicians who treat anogenital warts need to be knowledgeable about and have available at least one treatment that can be used in their office and one that can be used in the patient's home. Choosing the right treatment for each patient depends on a combination of factors including the number of warts, the anatomical site, the morphology of the lesions, and the patient's preference for management. ^{5 6} For example, patients with a small number of lesions can be quickly and effectively treated with ablation treatment, such as cryotherapy or electrosurgery. For patients who have a larger number of lesions, home treatment may be most suitable. It is important to provide careful explanation and written information on self examination, applying the treatment, and the possible side effects. Some patients are not comfortable with examining and treating their genitals and need their health providers to treat them.

To successfully manage anogenital warts the clinician must also have insight into the implications of the disease for patients. Although the lesions are benign they cause psychological distress and may cause problems in relationships because they are disfiguring and sexually transmitted.¹¹ When counselling patients it is important to emphasise that the time from acquiring the infection to the time the warts appear may be many months or even years. Most of those infected never develop warts.² This information can defuse difficulties in relationships and ameliorate the sense of isolation felt by patients. During the initial assessment the patient should be screened for other common sexually transmitted diseases, such as chlamydia, and patients should be advised to use barrier protection with new sexual contacts.¹² People in stable relationships will not need to use barrier methods because their partners will have been exposed to the infection by the time of consultation.

When compared with women who have a subclinical infection with human papillomavirus anogenital warts in women are not associated with an increased risk of cervical intraepithelial neoplasia. The presence of anogenital warts is therefore not an indication that women should have more frequent cervical smear tests; this should save many women from unnecessary physical and psychological morbidity.¹³

The management of anogenital warts has all the elements needed for cooperation to develop between primary care physicians and specialists. The use of guidelines should enable all practitioners to provide the most effective treatment available for patients with this common and distressing condition.

Raymond Maw, consultant physician. 

Royal Victoria Hospital, Belfast BT12 6BA (raymond.maw{at}royalhospitals.n-i.nhs.uk)

Geo von Krogh, associate professor. 

Department of Dermatovenereology, Karolinska Hospital, 171 76 Stockholm, Sweden (Geo.von.Krogh{at}ood.ki.se)

Acknowledgments

GVK has received a consultant fee or reimbursement of expenses at educational meetings related to anogenital human papilloma virus infection from the following companies: 3M, Stiefel, and Oclasse. 3M has funded clinical trials in his department.