What is the appropriate management for infected molluscum contagiosum, including treatment of the secondary bacterial infection and the underlying viral lesions?

Management of Infected Molluscum Contagiosum

For infected molluscum contagiosum, treat the secondary bacterial infection with appropriate antibiotics only when culture-confirmed, then proceed with physical removal of the underlying viral lesions using curettage, cryotherapy, or excision to prevent ongoing transmission and recurrence. 1, 2

Distinguishing True Infection from Inflammation

• True bacterial superinfection of molluscum lesions is rare, occurring in only 12% of cultured inflamed lesions. 2 The majority of "infected-appearing" molluscum lesions represent normal inflammatory responses as the immune system clears the virus, not bacterial superinfection. 1

• Obtain bacterial culture before prescribing antibiotics when superinfection is suspected, as antibiotics are routinely overprescribed despite negative cultures—71% of patients receive topical antibiotics and 63% receive systemic antibiotics unnecessarily. 2

• Consider true bacterial infection when lesions show purulent drainage, significant surrounding cellulitis, or systemic signs of infection rather than simple erythema or inflammation. 3, 2

Treatment of Confirmed Bacterial Superinfection

• When culture confirms bacterial pathogens, treat with appropriate antibiotics based on culture sensitivities and local resistance patterns. 2

• In immunocompromised patients with atypical presentations (giant lesions, necrotic lesions, minimal inflammation), consider cryptococcal infection as a differential diagnosis and obtain appropriate cultures. 3, 1

Definitive Management of Underlying Viral Lesions

First-Line Physical Removal Methods

Physical removal is the recommended first-line therapy to prevent transmission, reduce symptoms, and eliminate the viral reservoir that predisposes to recurrent inflammation or superinfection. 1, 4

• Curettage achieves cure in 70% of patients after one treatment and 96% after two treatments, with 97% patient satisfaction. 5 This is highly effective when performed in an appropriate setting with proper technique. 1, 5

• Cryotherapy with liquid nitrogen achieves complete response in approximately 93% of cases but carries higher risk of postinflammatory hyperpigmentation (particularly in darker skin tones) and uncommon scarring. 1

• Simple excision or excision with cautery are equally effective alternatives for first-line therapy. 1, 4

Critical Technical Points

• Identify and treat ALL lesions, including nascent ones, during the initial treatment session—failure to treat early lesions is a common cause of recurrence. 1, 4 Reducing viral load allows the host immune response to eliminate residual virus. 1, 4

• For periocular lesions with associated conjunctivitis, physical removal is imperative as the conjunctivitis will not resolve until the lesion is eliminated, though resolution may take several weeks post-treatment. 1, 4

Alternative Topical Treatments

• 10% potassium hydroxide solution has similar efficacy to cryotherapy (86.6% vs 93.3% complete response) with better cosmetic outcomes due to lower risk of hyperpigmentation. 1

• Cantharidin shows effectiveness in observational studies with 86% parent satisfaction and no serious adverse events in large retrospective reviews, though randomized trial evidence is limited. 1

• Imiquimod is NOT recommended—it showed no benefit compared to placebo in randomized controlled trials. 1

Special Populations

Immunocompromised Patients

• Multiple large lesions with minimal inflammation should prompt screening for immunodeficiency. 1, 4

• In immunosuppressed hosts, lesions may develop chronic ulcerations with persistent viral replication complicated by secondary bacterial AND fungal superinfection without adequate treatment. 3

• Consider referral to dermatology for extensive or recalcitrant disease. 1, 4

Common Pitfalls to Avoid

• Do not prescribe antibiotics empirically for inflamed molluscum lesions—the erythema typically represents normal immune clearance, not infection. 1, 2

• Do not use watchful waiting for symptomatic lesions, multiple lesions, or periocular lesions causing conjunctivitis—active treatment prevents transmission and complications. 1, 4

• Avoid treating sensitive areas (eyelids, lips, nose, ears) with cryotherapy due to higher complication risk. 1

• Do not miss nascent lesions during initial treatment, as this leads to recurrence and prolonged infectivity. 1, 4