Management of Cutaneous Wart

• Human papillomaviruses (HPV) infect epithelial tissues of skin and mucous membranes
• The most common clinical manifestation of these viruses is warts (verrucae)
• HPV type 1 commonly infects the soles of the feet and produces plantar warts, while HPV types 6 and 11 infect the anogenital area and cause anogenital warts

General

• depend upon the type of wart, its location, the degree of symptoms, the patient's cooperation, the patient’s desires, and the underlying immune status
• spontaneous regression occurs in as many as two-thirds of warts within two years
• virus is microscopic and, although the skin may look normal after treatment, there often is virus still present in the remaining tissue. If any infected tissue remains after treatment, the wart may recur
• Therapy may take several weeks or even months

Choice of Therapy
Salicylic Acid 
Availability 2-10% (hyperkeratotic skin), 20% (plantar warts), higher % available in plasters

• effective therapy for warts that can be used in both adults and children
• clearance of warts following salicylic acid therapy have varied widely, ranging from 0 percent to more than 80 percent.
• Potent preparations, such as 40 percent plasters (Mediplast or Duofilm patch), usually are reserved for thicker areas (eg, palms, soles, extremities); they are particularly useful for plantar warts
• Lesser strength preparations are used for the digits of young children and for thinner warts in adults
• Patients generally should be advised to apply the patch or liquid at bedtime after soaking the affected area in warm water for 10 to 20 minutes
• Adequate paring of hyperkeratosis is an essential component of successful treatment
• response to therapy is assessed after two to three weeks
• Treatment is often continued for one to two weeks after clinical removal of the verruca to help reduce recurrence

Liquid Nitrogen

• Cure rates from liquid nitrogen cryosurgery reported in randomized trials range from 14 percent to more than 90 percent
• Cryosurgery is also ill-suited to treat small facial flat warts due to the propensity to cause dyschromia

Cantharidin 0.7%

•  used in resistant cases in conjunction with or before salicylic acid preparations
• Bichloracetic acid or Trichloroacetic acid
• useful for warts on the palms or the soles. 
• Either agent may be applied to pared warts with a wooden toothpick every 7 to 10 days
• Application of salicylic acid preparations between visits quickens the response time

Tretinoin

• 0.05 percent, 0.1 percent cream; 0.01 percent, 0.025 percent gel is useful for flat warts, but improvement may take several weeks. 
• applied once or twice a day, with a goal of mild scaling and mild irritation. 
• highest strength tolerated should be used
• sun protection is important. Protect the normal surrounding skin with a barrier cream

Imiquimod

• commonly used for anogenital warts, imiquimod 5 percent cream can be used to treat nongenital warts
• nonscarring and it is painless to apply.

Recommendation

1. In children old enough to comply with the therapy, treat common, plantar, and palmar warts with salicylic acid
2. For dark-skinned adults and those who wish to avoid the discomfort of liquid nitrogen, treat with salicylic acid
3. In light-skinned adults with common, plantar, or palmar warts treat patients who want a rapid response to therapy with liquid nitrogen 

References:

1. www.uptodate.com
2. British Association of Dermatologists’ guidelines for the management of cutaneous warts 2014