What is the treatment approach for a patient with Molluscum contagiosum, considering the potential for contagion and varying severity of the infection in immunocompetent and immunocompromised individuals?

Molluscum Contagiosum Treatment

Primary Treatment Recommendation

Physical removal methods—including incision and curettage, simple excision, or cryotherapy with liquid nitrogen—are the first-line treatment for molluscum contagiosum in both immunocompetent and immunocompromised patients, particularly when lesions are symptomatic, multiple, or located near the eyes. 1, 2

Treatment Algorithm by Patient Population

Immunocompetent Children

• Physical removal (curettage, excision, or cryotherapy) is first-line therapy, with cryotherapy achieving approximately 93% complete response rates 1
• 10% potassium hydroxide solution is an equally effective alternative (86.6% complete response vs 93.3% for cryotherapy) that can be applied at home by parents, offering better cosmetic outcomes with lower risk of postinflammatory hyperpigmentation 1, 3
• Apply emollients regularly to control itching and treat associated xerosis 3
• Treat all lesions simultaneously, including nascent ones, as reducing viral load allows the host immune response to eliminate residual virus and significantly reduces recurrence risk 1, 3

Immunocompetent Adults

• Incision and curettage, simple excision with cautery, or cryotherapy are equally effective first-line options 2
• Identify and treat all lesions, including early dome-shaped papules without visible umbilication 2
• For limited disease, proceed directly with physical removal methods 2

Immunocompromised Patients (HIV, Organ Transplant, Immunosuppressive Medications)

• Multiple large lesions with minimal inflammation should immediately prompt consideration of immunocompromised state 1, 2
• Physical removal remains the treatment approach, though lesions are typically more extensive, refractory to treatment, and may present in atypical forms (giant, disseminated, necrotic, polypoidal, nodular, pseudocysts, or abscesses) 1, 4, 5
• Refer to dermatology for extensive or recalcitrant disease 1, 2
• Consider HIV testing in patients with atypical presentations, especially those already on immunosuppressive therapy 5
• Lesions persist for prolonged periods and are difficult to eradicate in this population 6, 4, 7

Special Anatomic Considerations

Periocular Lesions

• Lesions on or near eyelids with associated conjunctivitis require immediate physical removal to prevent follicular conjunctivitis 1, 2, 3
• Conjunctivitis may require several weeks to resolve after lesion elimination 1, 2
• Avoid cryotherapy on eyelids, lips, nose, and ears due to higher complication risk 1

Genital/Perianal Lesions

• Treatment is indicated to reduce sexual transmission risk, prevent autoinoculation, and improve quality of life 7
• Physical removal methods remain first-line 7

Treatments to Avoid

Imiquimod has no role in molluscum contagiosum treatment—randomized controlled trials in both adults and children (702 pediatric subjects studied) showed no benefit compared to placebo, with complete clearance rates of 24% for imiquimod versus 26-28% for vehicle 1, 8

• H2 antagonists (ranitidine) have no evidence of efficacy and should not be used 3
• Salicylic acid is contraindicated in children under 2 years due to systemic toxicity risk 3

Watchful Waiting Considerations

• Watchful waiting is reasonable only for asymptomatic, limited disease in immunocompetent patients 1
• Lesions typically persist 6-12 months but can last up to 4-5 years without treatment 1, 7
• However, the "watch and wait" approach increases transmission risk to others, extends infection duration, and causes psychosocial issues (anxiety, embarrassment, isolation) 9
• Lesions remain infectious throughout their entire course until complete resolution 1

Transmission Prevention

• Hand hygiene with alcohol-based disinfectant or soap and water is the most important preventive measure 1
• Avoid direct skin-to-skin contact with infected individuals 1
• Do not share towels, clothing, personal items, or equipment 1
• Cover all lesions with waterproof bandages if water exposure is unavoidable 1
• Limit exposure to swimming pools and hot tubs associated with known outbreaks, as hot tubs present higher transmission risk due to warmer water temperatures and shared seating surfaces 1
• Return to communal water facilities only when all lesions have completely resolved and no new lesions have appeared for several weeks 1

Critical Pitfalls to Avoid

• Failing to treat nascent lesions during initial treatment is the most common cause of recurrence 1, 3
• Neglecting periocular lesions can lead to persistent conjunctivitis requiring weeks to resolve 1, 2, 3
• Missing the diagnosis of immunocompromised state when multiple large lesions present with minimal inflammation 1, 2
• Using imiquimod based on outdated information—it is explicitly ineffective 1, 8

Follow-Up

• Follow-up is not usually necessary unless conjunctivitis persists or new lesions develop 1, 2
• Monitor for complete resolution of conjunctivitis after periocular lesion removal 1, 2