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Molluscum Dermatitis

John Montgomery5 min read

Molluscum Dermatitis

Molluscum contagiosum (MC) is a common poxvirus skin infection of young children. It causes clusters of small (1–6 mm), firm, shiny, dome-shaped papules, often with a central dimple (umbilication) and a white cheesy core. In toddlers the spots often appear in warm, moist folds such as the armpits, the backs of the knees and the groin, and on the trunk. They never appear on the palms or soles (DermNet 2021; NHS 2026). It spreads by skin-to-skin contact, shared towels and baths, and by scratching the virus into new skin (autoinoculation). Scratch-spread spots often form a line. The incubation period is about 2 weeks but can be up to 6 months (DermNet). Molluscum dermatitis is the itchy, pink, dry eczema patch that frequently forms around the spots. It can be widespread enough to hide the papules altogether (Siegfried & Hebert, J Clin Med 2015).

Molluscum Dermatitis [relates] Itch-Scratch Cycle Molluscum Dermatitis [part-of] Differential Diagnosis of Toddler Eczema

Interaction with atopic eczema. Molluscum tends to be more numerous and longer-lasting in children with Atopic Dermatitis because their skin barrier is defective (DermNet). Itch drives scratching, and scratching spreads the virus. MC in AD has been linked to Filaggrin mutations (Napolitano et al., Dermatol Ther 2022). Children who develop molluscum dermatitis, with or without AD, have a longer or more severe course (Siegfried & Hebert 2015, citing Berger 2012). However, some of the apparent “spread” may be an immune id reaction (autoeczematisation) rather than new infection (Siegfried & Hebert 2015, citing Netchiporouk & Cohen 2012). Distant eczematous or Gianotti–Crosti-like eruptions can occur, and these may herald clearance (DermNet).

Conflict: [DermNet, 2021; Napolitano et al., 2022] say molluscum is more frequent, numerous or prolonged in children with AD, linked to barrier defects and FLG mutations. Napolitano also notes “there is not necessarily an association”, and [Türe Avcı et al., Children, 2026] says it “remains unclear whether molluscum-associated dermatitis occurs predominantly in individuals with underlying AD”. Unresolved — add to open_questions.

Atopic Dermatitis [worsens] Molluscum Dermatitis Skin Barrier Dysfunction [causes] Molluscum Dermatitis Filaggrin [relates] Molluscum Dermatitis

Telling it apart from an eczema flare. Because the small papules are hard to see inside inflamed skin and the patch itches, molluscum dermatitis is often misdiagnosed as AD (Türe Avcı et al., Children 2026). Look closely at the centre of the patch for one or more pearly, dimpled bumps. A careful examination usually finds the papule (Napolitano 2022). On dermoscopy, a clinician sees a central pore with white-to-yellow lobular structures and a “crown” of vessels around it (Türe Avcı 2026). Clues that suggest molluscum rather than eczema include an eczema patch in an unusual place, an isolated patch around a fold, a patch that keeps recurring at the same spot, or siblings with the same bumps.

The BOTE sign. As molluscum resolves, individual spots often turn red, swollen, tender and crusted for a week or two. Parents and clinicians frequently mistake this for a bacterial infection. Butala, Siegfried & Weissler (Pediatrics 2013; one case plus 7 retrospective cases) showed that this inflammation is usually the immune system clearing the virus, not superinfection, and that it needs no antibiotics. They named it the BOTE (“beginning of the end”) sign. True secondary infection (Impetigo) is uncommon. It presents with sudden tenderness, pus, spreading redness or honey crusts, and then needs review (Siegfried & Hebert 2015; DermNet).

Molluscum Dermatitis [contradicts] Atopic Dermatitis Molluscum Dermatitis [relates] Impetigo Molluscum Dermatitis [relates] Infected Eczema

Whether to treat. UK and NZ guidance leans strongly towards watchful waiting. Molluscum is self-limiting: about half of children clear by 12 months and two-thirds by 18 months, with or without treatment (DermNet, citing Olsen 2015). The NHS says spots usually clear within 18 months and treatment is rarely needed. Physical treatments such as squeezing, cryotherapy and curettage are painful for toddlers and can scar or spread the virus (DermNet). For the eczema around the spots, treat the skin as you would eczema: regular unperfumed emollients and, if needed, a short course of a mild topical steroid such as Hydrocortisone (DermNet; NHS). DermNet notes the dermatitis “is unlikely to fully resolve until the molluscum infection has cleared up”. Controlling the itch reduces scratching and so reduces spread. To limit spread, keep spots covered (waterproof plasters for swimming), do not share towels or baths, and keep nails short. Children can still attend nursery (DermNet; NHS). The NHS advises seeing a GP for spots near the eyes, spots that are very itchy, painful or crusted, or a weakened immune system. Very extensive or unusual molluscum alongside severe eczema and recurrent infections is a red flag for immunodeficiency (see Differential Diagnosis of Toddler Eczema).

Emollient Therapy [treats] Molluscum Dermatitis Hydrocortisone [treats] Molluscum Dermatitis Molluscum Dermatitis [precedes] When to Refer

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