What is the recommended management for Human Papillomavirus (HPV) warts located near the nail bed?

Management of HPV Warts Near the Nail Bed

For HPV warts near the nail bed (periungual warts), start with topical salicylic acid 15-26% applied daily after paring, with occlusion if possible, for 3-4 months as first-line therapy, and if this fails after 3 months, switch to cryotherapy with liquid nitrogen every 1-2 weeks. 1, 2

First-Line Treatment: Topical Keratolytic Therapy

• Salicylic acid (15-26%) is the recommended first-line treatment for periungual warts, applied daily after removing the thick keratin layer, with occlusion if possible, continuing for 3-4 months 1, 2
• The method requires paring down the wart before application, but care must be taken to avoid abrading surrounding normal skin as this may spread the infection 1
• Keratolytic agents work by promoting exfoliation of epidermal cells and at high concentrations act as irritants, potentially stimulating host immunity 1
• This approach is particularly appropriate for periungual warts because they are usually small and of short duration, making them responsive to medical treatment 2, 3

Second-Line Treatment: Cryotherapy

• If salicylic acid fails after 3 months or is contraindicated, cryotherapy with liquid nitrogen should be used, keeping the wart frozen for 15-30 seconds and repeating every 1-2 weeks for at least 3 months or up to six treatments 1, 4
• Cryotherapy is relatively inexpensive, does not require anesthesia, and does not result in scarring if performed properly 1, 4
• The efficacy of cryotherapy ranges from 63-88% in clinical trials, with recurrence rates of 21-39% 5

Third-Line Options for Recalcitrant Cases

If both first and second-line therapies fail after appropriate treatment duration:

• Intralesional bleomycin (0.1-1.0 mg/mL) injected or pricked into the wart after local anesthesia can be used for one to three treatments, though it is painful during and after treatment 1
• Pulsed-dye laser therapy after paring and/or salicylic acid pretreatment, using 7-10 J/cm² for two to four treatments at appropriate intervals 1
• Surgical excision via electrosurgery or Er:YAG laser has an excellent safety profile for periungual warts, though definitive cure is not guaranteed and recurrence can occur 2

Critical Pitfalls to Avoid

• Never use aggressive destructive therapy near the nail bed as this can result in permanent nail dystrophy, scarring, or chronic pain syndromes 1, 2
• Avoid podofilox, podophyllin, and imiquimod for periungual warts as these are designed for genital warts on moist surfaces and are not appropriate for the nail area 1
• Do not overtreat - change treatment modality if the patient has not improved substantially after three provider-administered treatments or if warts have not cleared after six treatments 1
• Recognize that periungual warts are favored by maceration and trauma, especially nail biting, so addressing these behavioral factors is essential to prevent recurrence 2

Special Considerations

• Periungual warts are usually caused by HPV types 1,2, and 4 (not the genital HPV types 6 and 11), which explains why they respond differently to treatment than genital warts 2
• The natural course of warts makes aggressive approaches restricted to selected cases - spontaneous resolution occurs in 20-30% of patients within 3 months without treatment 1, 2
• Treatment removes visible warts but does not eradicate HPV infection, and recurrence is common (approximately 30%) regardless of treatment method due to reactivation of subclinical infection 5, 4
• In immunocompromised patients, warts may be large, extensive, and resistant to treatment, requiring more aggressive or combination approaches 1