What is the best course of action for a 10-year-old male with non-healing plantar warts, hyperpigmentation, and symptomatic bilateral hammer toes, who has been using OTC salicylic acid (17%) and has a history of congenital birthmarks and recently developed discomfort in his toes?

Management of Non-Healing Plantar Warts in a 10-Year-Old

This child requires immediate dermatology referral for evaluation of the extensive hyperpigmentation and birthmarks, and should discontinue current wart treatment due to signs of inflammation; podiatry referral is appropriate for symptomatic hammer toes. 1

Immediate Actions for Plantar Warts

Discontinue Current Treatment

• Stop the OTC salicylic acid 17% immediately due to the presence of surrounding erythema and warmth on one wart, which suggests excessive inflammation or possible secondary infection 1, 2
• The current regimen has failed after 1 month of treatment, and continuing ineffective treatment beyond recommended timeframes risks complications without benefit 1
• Application every 3 days is suboptimal; salicylic acid should be applied daily after paring down the wart with occlusion for maximum efficacy 3, 1

Assess for Infection

• The wart with surrounding erythema and warmth requires evaluation to rule out secondary bacterial infection, though the absence of purulent drainage, spreading redness, or systemic symptoms makes deep infection less likely 2
• If infection is present, debridement of devitalized tissue and antimicrobial therapy would be needed before resuming wart treatment 2

Recommended Treatment Algorithm for Plantar Warts

First-Line Treatment (After Inflammation Resolves)

• Restart salicylic acid 15-26% applied daily after paring down the wart, with occlusion, for 3-4 months as the first-line treatment based on highest quality guideline evidence 3, 1
• The previous 17% concentration was appropriate, but the application frequency was inadequate 1, 4
• Salicylic acid makes warts 16 times more likely to clear than placebo, with a mean cure rate of 49% 1
• Critical technique: Abrade or pare down the wart before each application to remove dead tissue and enhance penetration; apply directly to the wart avoiding surrounding normal skin; cover with occlusive dressing 1

Second-Line Options (If No Response After 3 Months)

• Contact immunotherapy with DPCB or SADBE achieves 88% complete clearance in palmoplantar warts over a median of 5 months 1
• Intralesional Candida antigen shows 47-87% clearance rates and is superior to other intralesional options 1
• 5-Fluorouracil 5% cream under occlusion achieves 95% clearance in plantar warts after 12 weeks of daily application, significantly more effective than occlusion alone (95% vs 10%) 1
• Cryotherapy every 2-4 weeks for at least 3 months is an option, though plantar warts respond poorly compared to hand warts; double freeze-thaw cycles may improve efficacy to 65% but cause more pain and scarring risk 1, 5

Third-Line Options for Single Resistant Lesions

• Bleomycin intralesional injection (0.1-1 U/mL) after local anesthesia, 1-3 treatments, though this causes significant post-treatment pain (mean 7.1 on VAS) 3, 6
• Recent evidence shows bleomycin requires fewer sessions (average 1.8) compared to other treatments but is more painful 6
• Cantharidin 0.7% applied by provider achieves clearance with 1-4 treatments over 16 weeks; a combination formulation with podophyllotoxin and salicylic acid showed 95.8% complete eradication, with 86.8% requiring only a single application 1, 7

Treatments to Avoid

• Do not use cryotherapy as first-line treatment in this child, as a recent high-quality RCT showed no difference between cryotherapy and salicylic acid (14% vs 14% clearance at 12 weeks), and cryotherapy is particularly ineffective for plantar warts 5
• Do not use formaldehyde or glutaraldehyde as these are allergenic and carry risk of deep necrosis with repeated application 3
• Do not use intralesional acyclovir as it shows no superiority over placebo and lacks guideline support 1

Dermatology Referral: High Priority

Indications for Urgent Dermatology Evaluation

• The extensive hyperpigmentation that developed at age 6 (large area over left shoulder extending anteriorly, posteriorly, and to posterior left leg) requires evaluation for neurocutaneous disorders 1
• Multiple congenital birthmarks in various locations raise concern for potential underlying syndromes that may require monitoring 1
• This is a higher priority than the plantar warts themselves, as certain neurocutaneous conditions can affect long-term morbidity and quality of life 1

Dermatology Can Also Optimize Wart Management

• Dermatologists can provide second-line treatments such as contact immunotherapy, intralesional Candida antigen, or bleomycin that are not typically available in primary care 1
• They can assess whether the current inflammation represents treatment reaction versus infection 2

Podiatry Referral: Appropriate

Indications for Podiatry Evaluation

• Symptomatic bilateral hammer toes with 6 months of progressive discomfort warrant evaluation, particularly with the "pulling downward" sensation 1
• The patient is at an age where conservative management (toe exercises, proper footwear, padding) may prevent progression and avoid future surgical intervention 1
• Podiatry can also coordinate plantar wart treatment if dermatology is not readily available, as they have expertise in managing these lesions 7

Common Pitfalls to Avoid

• Do not continue ineffective treatment beyond 3 months without switching modalities; this child's current regimen has already failed at 1 month with improper application frequency 1
• Do not treat through active inflammation; allow the inflamed wart to heal before resuming treatment to avoid complications 2
• Do not use surgical interventions without attempting conservative treatments first, as evidence for surgical approaches is limited and scarring can cause permanent pain at weight-bearing sites 3
• Do not overlook the dermatologic findings in favor of focusing solely on the warts; the hyperpigmentation and birthmarks may represent a more significant underlying condition 1