What is the recommended management for multiple cutaneous warts (verruca vulgaris) in an otherwise healthy child?

Management of Multiple Cutaneous Warts in a Pediatric Patient

Initial Approach: Age-Dependent Strategy

For children under 5 years old, watchful waiting without treatment is the most appropriate initial approach, as warts typically resolve spontaneously within 1-2 years (65% by 2 years, 80% by 4 years) and painful treatments should be avoided in young children. 1, 2

For children 5 years and older with multiple warts, treatment should be initiated with topical salicylic acid unless the warts are asymptomatic and the family prefers observation. 1, 2

First-Line Treatment: Topical Salicylic Acid

Salicylic acid 15-26% applied daily for 3-4 months is the first-line treatment for multiple warts in children, with the strongest evidence (Level A recommendation) for safety and efficacy. 3, 1, 2

Application Protocol:

• Soak the wart in warm water for 5-10 minutes to soften thickened skin 1, 4
• Pare down the wart using a disposable emery board, pumice stone, or callus file, removing only the white, thickened keratin layer 1, 4
• Stop paring if pinpoint bleeding occurs, as this indicates reaching the dermal papillae 4
• Apply salicylic acid daily after paring and cover with occlusion (bandage or tape) to enhance penetration 1, 2, 4
• Discard the paring tool after use or dedicate it solely to the wart to prevent spreading infection 4

Critical Safety Precautions:

• Limit the treatment area to avoid excessive systemic absorption and salicylate toxicity, particularly in children under 12 years 3, 1, 2
• Monitor for signs of salicylate toxicity: tinnitus, nausea, vomiting, hyperventilation, and confusion 1, 2
• Avoid use during chickenpox or influenza-like illnesses due to Reye syndrome risk 3, 1, 2
• Do not use salicylic acid 6% cream, lotion, gel, or 15% plaster in children under 2 years of age 3

Treatment Duration:

Continue salicylic acid for a full 3-4 months before considering it a failure, as premature discontinuation is a common pitfall. 1, 4

Second-Line Treatment: Cryotherapy

If salicylic acid shows no improvement after 3 months of proper use, switch to cryotherapy with liquid nitrogen. 1, 2, 4

• Freeze the wart for 15-30 seconds per treatment 1, 4
• Repeat every 2-4 weeks for at least 3 months or up to six treatments 3, 1, 4
• Note that cryotherapy is more effective than salicylic acid but carries higher risk of pain and blistering, which may be poorly tolerated in young children 5

Combination Therapy:

Combination treatment with salicylic acid and cryotherapy can be undertaken for more aggressive management, though this increases the risk of adverse effects. 3, 2

Third-Line Treatments for Recalcitrant Warts

When first- and second-line treatments fail after adequate trials:

Immunotherapy Options:

• Intralesional immunotherapy with Candida antigen has shown 72% complete clearance within 8 weeks 1
• Topical immunotherapy with diphencyprone (DPC) or squaric acid dibutyl ester (SADBE) applied at appropriate strength from twice weekly to every 3 weeks for 3-6 months (Level C evidence) 3, 1, 4

Other Modalities:

• Intralesional bleomycin: 0.1-1 mg/mL solution injected into wart after local anesthesia, one to three treatments (Level C evidence, but painful) 3, 1, 4
• Pulsed dye laser: 7-10 J/cm² after paring and/or salicylic acid pretreatment, two to four treatments usually needed (Level C evidence) 3, 1, 4

Special Considerations by Location

Plantar Warts:

Plantar warts have lower cure rates due to thicker cornified layer reducing treatment penetration. 3, 1

• Use more aggressive paring before treatment 3
• Consider combination therapy earlier in treatment course 3

Plane Warts (Face/Hands):

Use lower concentrations of salicylic acid (2-10%) or cautious use of 12-17% paint without occlusion, as destructive agents are more likely to produce scarring at these sites. 3, 4

• Apply gentler cryotherapy with milder freeze 3

Filiform Warts (Facial):

Curettage, cautery, or hyfrecation may be more appropriate than topical treatments for filiform warts. 3, 2

Common Pitfalls to Avoid

• Do not stop treatment prematurely: salicylic acid requires 3-4 months and cryotherapy needs at least 3 months or six treatments before declaring failure 4
• Avoid aggressive paring that damages surrounding skin, as this spreads infection 3, 4
• Do not use multiple destructive modalities simultaneously in initial treatment, as this increases scarring risk without proven benefit 4
• Avoid damaging adjacent skin during treatment in the beard area or with shaving, as this can spread infection 3

When to Consider Observation Only

In healthy children without functional impairment or significant cosmetic concern, observation for 6 months to 2 years is reasonable, as spontaneous resolution occurs in 65% by 2 years and 80% within 4 years regardless of treatment. 1, 4, 6

Treatment should only be initiated if warts cause significant pain, functional impairment, or psychosocial distress. 1, 2, 7