🦠 Molluscum contagiosum is a common, highly contagious viral skin infection caused by a DNA poxvirus. 👶 Most often affects children & young adults, presenting with small, pearly papules with central umbilication. ✅ Harmless & self-limiting, but widespread/persistent cases may need treatment.

📖 About

Definition: Viral infection with pearly papules + central dimple.
Etiology: Caused by molluscum contagiosum virus (MCV), a member of the Poxviridae family.
Epidemiology: Common in children, immunocompromised patients, and sexually active adults.
Transmission: Direct contact, fomites (towels, clothes), and sexual contact in adults.

📌 Lesions are most often seen on the trunk, limbs, and in adults → genital area.

🩺 Clinical Features

✨ Lesion: Small, pearly papule with central umbilication.
📏 Size: 2–6 mm, may enlarge to 10–20 mm.
📍 Distribution: Trunk, limbs, face (children), genitalia (adults).
➰ Koebner phenomenon: Lesions may appear at trauma sites.
😣 Mild–moderate pruritus (↑ with atopic dermatitis).
🧾 No systemic symptoms; widespread lesions in adults → consider HIV testing.
🧴 Associated with atopic eczema → more extensive disease.

👁️ Clinical Signs

🔎 Investigations

🧑‍⚕️ Clinical diagnosis usually sufficient.
🔬 Skin biopsy if atypical (to rule out psoriasis/eczema).
🧫 KOH test if fungal infection suspected.
🧪 HIV test in adults with widespread disease.

🧾 Differential Diagnosis

🍄 Tinea corporis (ringworm) – scaly, ring-shaped, no umbilication.
🧪 Secondary syphilis – serological confirmation needed.
🌿 Eczema (Atopic dermatitis) – itchy, scaly, often chronic.
⭕ Granuloma annulare – ring-shaped, no umbilication.

💊 Management

⏳ Observation: Usually resolves spontaneously in 6–18 months.
😌 Symptomatic:
- Antihistamines for itch (loratadine, diphenhydramine).
- Topical steroids (e.g., hydrocortisone) + emollients for eczema/itch.
⚡ Local treatments:
- Cryotherapy (liquid nitrogen).
- Curettage (scraping lesions).
- Imiquimod (off-label, limited effect).
- Ophthalmology referral if eyelid lesions.
🌐 Systemic:
- HAART in HIV-positive patients often clears lesions.
🛡️ Prevention:
- Avoid sharing towels/clothing.
- Maintain good hygiene.
- Children do not need exclusion from school/swimming.

📉 Prognosis

✅ Self-limiting → clears in 6–18 months.
🙌 Complete recovery without scarring in most.
🎨 Post-inflammatory hyper/hypopigmentation possible (esp. in darker skin).
🔁 Recurrence rare (<3%).

📌 Conclusion

Molluscum contagiosum is a benign, self-limiting poxvirus infection. Treatment is not always necessary, but options exist to expedite clearance or reduce symptoms, especially in immunocompromised patients.

📚 References

Harmon AJ, Gupta AK. Pityriasis rosea: An update. Dermatology, 2004; 208(2):145–152.
Mayo Clinic. Molluscum Contagiosum. Link
NIH. Molluscum Contagiosum. Link
WHO. Skin Conditions. Link
AAD. Molluscum Contagiosum Overview. Link

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Molluscum contagiosum