Guidelines point to the need for new, reliable wart treatments and help to provide an evidence-based rationale for currently available treatments.
Sponsoring Organization: British Association of Dermatologists
Target Population: Primary care providers, dermatologists, pediatricians
Background and Objective
Warts, or verrucae, are a common skin condition caused by human papilloma virus (HPV) infection. More than 150 genotypes have been identified. HPV types 1, 2, 4, 27, and 57 are the most frequent strains in common warts, and HPV 3 and 10 cause plane warts (verruca plana). Compilers of these guidelines reviewed research on the management of warts published between January 1999 and March 2014 in the English-language literature.
Meta-analysis shows preparations containing salicylic acid as the active ingredient — the most common destructive wart therapy — to be more effective than placebo but less effective than cryotherapy for warts of the hands.
Liquid nitrogen cryotherapy is the most common treatment used by physicians. Results for plantar warts, but not hand warts, can be improved by paring the wart prior to treatment. The median cure rate with cryotherapy is 49%. It is more effective on the hands than on the feet. After 6 weeks, cryotherapy every 4 weeks produced cure rates equal to treatment every 2 to 3 weeks.
No high-quality studies have evaluated curettage, cautery, or CO2 laser treatment.
A few studies show that photodynamic therapy with topical aminolevulinic acid and pulsed dye laser are more effective than placebo. These methods may be combined with other therapies.
Topical 5% 5-fluorouracil applied with occlusion for up to 4 weeks has been shown to cure up to 95% of warts. In addition, 0.5% 5-FU in combination with salicylic acid was significantly better than salicylic acid alone. Several open-label studies show response rates of 65% to 85% with intralesional bleomycin, albeit with possible pain at the injection site.
Topical retinoids are effective primarily for flat warts.
Diphencyprone and squaric acid dibutylester are immunomodulatory agents seen in retrospective studies to regress warts in >85% of patients. Similar results were noted with intralesional candida, mumps, and tuberculin antigens. H2-receptor antagonists are thought to augment cell-mediated immunity. Cimetidine, however, was ineffective in randomized, controlled trials. Ranitidine was found to cause complete wart regression in 49% of patients in an open-label study. Imiquimod, used primarily for condyloma acuminata, was reported in open-label trials to regress 50% to 76% of cutaneous warts.
Little evidence supports alternative therapies — acupuncture, homeopathy, hypnosis — as effective wart treatments.
Sterling JC et al.
British Association of Dermatologists' guidelines for the management of cutaneous warts 2014.
Br J Dermatol 2014 Oct; 171:696.