Can molluscum contagiosum ever present as a pedunculated lesion, especially in immunocompromised patients?

Morphology of Molluscum Contagiosum: Pedunculated Variants

Yes, molluscum contagiosum can present as pedunculated lesions, particularly in immunocompromised patients such as those with HIV/AIDS, where atypical morphologies including polypoidal (pedunculated) forms are well-documented. 1

Classic vs. Atypical Presentations

Standard Morphology

• The typical presentation consists of skin-colored, whitish, or pink papules with a shiny surface and central umbilication, appearing as dome-shaped lesions 2-5 mm in diameter 1, 2, 3
• Early lesions may appear as simple dome-shaped papules without central depression, requiring careful examination for diagnosis 1

Atypical Morphologies in Immunocompromised Patients

• In immunocompromised patients, especially those with HIV, atypical manifestations include giant, disseminated, necrotic, polypoidal (pedunculated), nodular forms, pseudocysts, or abscesses 1
• These atypical presentations often occur with minimal inflammation and may lack the classic umbilication 1
• Agminate varieties (where individual papules join together) can also occur in HIV-positive patients 4
• Ulcerating forms have been documented in immunocompromised children with acute lymphoblastic leukemia 5

Clinical Recognition and Diagnostic Approach

Key Examination Points

• Look for shiny, dome-shaped papules even without umbilication, and assess the distribution pattern 1
• Evaluate for associated findings such as conjunctivitis (if periocular), perilesional eczema, or inflammatory reactions 1
• Multiple large lesions with minimal inflammation should prompt screening for immunocompromised state 1, 2

When Morphology is Atypical

• Dermoscopy can facilitate diagnosis when clinical appearance is uncertain 1, 3
• In cases with atypical presentations or diagnostic uncertainty, particularly in immunocompromised patients, consider dermoscopy or referral to dermatology 1
• Skin biopsy should be performed for accurate diagnosis of atypical cutaneous lesions in immunocompromised patients 5
• Consider cryptococcal infection as a differential diagnosis in HIV patients, as it can present with umbilicated papules resembling molluscum 1, 2

Common Pitfall to Avoid

• Do not dismiss lesions that lack central umbilication or have unusual morphology (including pedunculated forms) as "not molluscum" without further investigation, especially in immunocompromised patients where atypical presentations are the norm rather than the exception 1, 5