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Cutaneous warts and molluscum contagiosum
Cutaneous warts are caused by "skin" HPV types (1, 2, 4) and molluscum by a poxvirus; both are common in children, usually clear on their own within months to years, and treatment is chosen by site, symptoms and the family's wishes.
Why it matters in the exam
The exam shows a child with small, skin-coloured, pearly papules with a central dimple (umbilication) on the trunk and in the folds — molluscum — or a painful plantar wart that differs from a callus because skin lines are interrupted and black dots of thrombosed vessels are seen. The question tests treatments: salicylic acid and cryotherapy for warts, and for molluscum — watchful waiting, cantharidin, curettage or cryotherapy. Remember the "beginning of the end" sign — inflammation around molluscum lesions that signals clearance and is not an infection — and the meaning of widespread or large facial molluscum in an adult, which raises suspicion of HIV, and of genital molluscum in an adult, which counts as a sexually transmitted infection. In the immunosuppressed and transplant recipients many resistant warts are common, and "atypical" warts may be SCC. Flat warts on the face should also be told apart from acne. Warts and molluscum do not require exclusion from school or the pool. In children with atopic dermatitis molluscum spreads more because of scratching, so the eczema itself should also be treated.
Key points
- Cutaneous warts are caused by skin HPV types and molluscum by a poxvirus, and both are common in children.
- Most warts and molluscum clear on their own within months to years, so watchful waiting is a legitimate option.
- The main treatments for warts are salicylic acid and cryotherapy, and for molluscum cantharidin, curettage and cryotherapy.
- Inflammation around molluscum is the "beginning of the end" sign of clearance and does not need antibiotics.
- Widespread facial molluscum in an adult or very many warts require an HIV test and immunosuppression work-up.
Summary table
| Lesion | Appearance | Cause and population | Treatment |
|---|---|---|---|
| Common wart (verruca vulgaris) | Rough papule with black dots, on the hands | HPV 2 and 4; children | Salicylic acid, cryotherapy; usually clears |
| Plantar wart | Ingrown wart painful on walking, skin lines interrupted | HPV 1; athletes and pools | Salicylic acid, cryotherapy, paring |
| Flat wart (verruca plana) | Small flat papules on the face and backs of the hands, sometimes along a scratch | HPV 3 and 10 | Topical retinoids, imiquimod |
| Molluscum contagiosum | Pearly papules with a central dimple, on the trunk and folds | Poxvirus; children, atopic dermatitis | Watchful waiting, cantharidin, curettage, cryotherapy |
| Molluscum in an adult | Genital — sexually transmitted; widespread and large on the face — immunosuppression | HIV | HIV test and other sexually transmitted infection tests |
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Sources
- British Association of Dermatologists guidelines for the management of cutaneous warts, 2014 — Treatment ladder
- AAP Red Book — Report of the Committee on Infectious Diseases, 2024 — Molluscum contagiosum and papillomaviruses
- European guideline on molluscum contagiosum (IUSTI), 2014 — Management
Sources are given for further reading; the text is written afresh and not copied from them.
Reviewed by the Examqo AI Professor · 2026-11-06. The text may contain errors; when in doubt, check the source.