Viral Warts (HPV)

Definition

• Caused by the human papillomavirus (HPV), a double-stranded DNA virus. Warts typically present as firm, keratinous papules or plaques with red or black dots (thrombosed capillaries) on their surface.

Types

Common Warts (Verruca Vulgaris)

• Rough, papillomatous, hyperkeratotic, cauliflower-like lesions

• Usually on hands, knees, elbows

• Subtypes:

  • Plantar warts: On soles, can be painful with inward growth from pressure

  • Subungual warts: Under fingernails or toenails

  • Periungual warts: Around nail margins, often harder to treat, may damage nail bed

Plane (Flat) Warts (Verruca Plana)

• Small, flat, smooth, skin-coloured or brown

• Commonly on face, neck, dorsal hands, limbs

• Often linked to HPV types 3 and 10

• Can appear in clusters, sometimes following scratch lines (Koebner phenomenon)

Filiform Warts

• Long, slender, tag-like protrusions

• Often on the mouth, nose, eyelids, or beard area

Diagnosis

• Clinical: Based on the classic verrucous appearance

• Biopsy: Rarely needed unless suspicion of squamous cell carcinoma (especially in immunocompromised patients)

Differential Diagnosis

• Seborrhoeic Keratosis

• Squamous Cell Carcinoma (especially in older or immunosuppressed)

• Plantar Corn & Callus (foot lesions)

Management

Common Warts (Verruca Vulgaris)

• Aim: Irritate or destroy the lesion to stimulate host immune response

• Treatments often require multiple sessions

First-Line

• Salicylic Acid (up to 40% strength):

  • Apply daily for up to 3 months

  • Cover with tape or foam cushioning to protect surrounding skin

  • Soak in warm water beforehand to soften the wart

• Cryotherapy (liquid nitrogen) if salicylic acid fails or if quick resolution is preferred

  • Usually repeated at 2–3 weekly intervals

Special Cases

• Plantar warts: May need higher salicylic acid (e.g. 60%) or more prolonged cryotherapy due to thicker skin

• Subungual & Periungual warts: Treat carefully to protect nail bed; curettage plus cryotherapy or high-concentration salicylic acid

Plane (Flat) Warts (Verruca Plana)

• Often resolve spontaneously within 6–12 months

• Topical Retinoids (e.g. Tretinoin 0.05% cream daily for ≥3 months) if needed

  • Avoid in pregnancy due to potential teratogenic risk

Precautions

• Surgical Excision of warts not routinely recommended (risk of scarring, recurrence)

• For cosmetically sensitive areas (face, periungual region), consider referral to dermatology

Notes

• Immunocompromised patients may have more extensive or recalcitrant warts

• Many warts regress spontaneously over 1–2 years, especially in children

• HPV vaccines target anogenital cancer subtypes but do not specifically prevent cutaneous warts