What is the diagnosis and management of verruca vulgaris in a patient presenting with multiple lesions on the tibia, dorsum of the foot, and below the lateral malleolus?

Diagnosis and Management of Verruca Vulgaris

Diagnosis

Verruca vulgaris is primarily a clinical diagnosis based on characteristic features: benign, typically painless, hyperkeratotic papules or nodules occurring on any epithelial surface, most commonly on hands, feet, and around nails. 1

Key Diagnostic Features

• Typical appearance: Well-circumscribed, flesh-colored to hyperkeratotic lesions with a white pebbly or papillary surface 2
• Multiple lesions are common, occurring via autoinoculation 2
• Painless nature is characteristic; pain suggests alternative diagnosis or complications 1
• Confirmatory test: Pare down the lesion to reveal pinpoint bleeding as capillary loops of elongated dermal papillae are exposed 3

Red Flags Requiring Immediate Biopsy (Within 2 Weeks)

Any atypical features mandate biopsy to exclude malignancy, particularly squamous cell carcinoma or verrucous carcinoma. 4, 3

• Presence of pruritus (itching is NOT characteristic of verruca vulgaris) 4
• Progressive growth over observation period 2
• Ulceration or spontaneous bleeding 2
• Change from soft to indurated or fixed consistency 2
• Development of pain or functional impairment 2
• Prolonged duration with atypical symptoms 4

Differential Diagnosis Considerations

For lesions with atypical features, biopsy must exclude: 4, 3

• Squamous cell carcinoma
• Verrucous carcinoma
• Actinic keratoses
• Other keratotic lesions
• Underlying bone tumors (particularly in foot/hand lesions resistant to treatment) 5

Management Algorithm

Step 1: Initial Assessment

For typical lesions <5mm, soft consistency, normal coloration, and stable appearance: Observe for 2-3 weeks 2

• Avoid local trauma to affected area 2
• Maintain good hygiene 2
• This prevents over-treatment of lesions that may spontaneously resolve 2

Step 2: Natural History Considerations

• In children: 30% regress within 6 months, approximately 60% within 2 years 1
• In adults: Warts persist much longer (5-10 years not uncommon), whereas children often clear within 1-2 years 3
• Spontaneous clearance is significantly slower in adults than children 3

Step 3: Treatment Options for Confirmed Verruca Vulgaris

Treatment modalities are geared toward chemical or physical destruction of infected epithelium: 1

First-Line Topical Therapy

• Salicylic acid 6%: FDA-approved topical aid for removal of excessive keratin in verrucae 6
• Application of salicylic acid-based products 1
• Tretinoin (retinoic acid) cream 1

Second-Line Physical Destruction

• Cryotherapy with liquid nitrogen 1
• Surgical excision (paring) 1
• Laser removal (CO2 laser is excellent modality for problematic or recurrent warts) 7
• Topical immunomodulating agents 1

Combination Therapy

• Cantharidin combined with podophyllotoxin-salicylic acid (effective but associated with pain and blistering) 1

Important caveat: More destructive methods may lead to pain that inhibits athletic activity 1

Step 4: Definitive Surgical Management

Complete surgical excision is the standard of care for: 4, 2, 3

• Atypical presentations requiring biopsy confirmation 4, 3
• Lesions persisting beyond 2-3 week observation period 2
• Confirmed HPV-associated lesions in immunosuppressed patients (due to risk of dysplasia and malignancy) 2
• Giant, chronic, isolated, solitary, recalcitrant lesions involving nail and nail bed 8

Surgical technique: Excision with adequate margins is treatment of choice 9

Step 5: Follow-Up Protocol

• Re-evaluate at 2-3 weeks for lesions under observation 2
• Any change in size, color, or texture during observation warrants immediate biopsy 2
• Immunosuppressed patients require more frequent follow-up due to increased recurrence risk and higher malignancy risk 2

Critical Pitfalls to Avoid

• Missing underlying pathology: Failure to consider bone tumors in hand/foot lesions resistant to treatment can delay diagnosis for years 5
• Delayed biopsy: Any lesion with red flag features requires biopsy within 2 weeks to avoid delayed diagnosis of malignancy 4, 2
• Assuming pruritus is normal: Itching suggests alternative diagnosis such as lichen planus or inflammatory dermatoses, NOT verruca vulgaris 4
• Over-treatment: Unnecessary excision of benign lesions causes avoidable morbidity 2
• Misdiagnosis of chronic lesions: Giant, chronic lesions lose characteristic histopathologic features; multiple sections should be examined and extreme care taken to avoid misdiagnosis 8

Special Populations

Immunosuppressed Patients

• Require closer monitoring as HPV lesions persist longer 2
• Carry higher malignancy risk 2
• Complete surgical excision preferred due to risk of dysplasia 2

Oral Verruca Vulgaris

• Most commonly occurs on palate, followed by lip, tongue, buccal mucosa 9
• Prompt surgical removal warranted as HPV has been linked to squamous cell carcinoma in oral cavity and oropharyngeal areas 10
• Surgical excision with adequate margins is treatment of choice 9