Skin, Molluscum contagiosum

Molluscum contagiosum is a poxvirus infection affecting skin and mucous membranes. The infection produces small pearly papules with central umbilication and can persist for months to a few years. The rash is spread by direct person-to-person physical contact and through contaminated fomites. An infected person can spread it to other parts of the body through scratching (autoinoculation). Histology shows a lobular endophytic growth of hyperplastic squamous epithelium. Keratinocytes contain large molluscum bodies (eosinophilic to basophilic cytoplasmic inclusions) containing viral particles. The inclusions progressively enlarge toward the surface where they occupy almost the entire infected cell. Secondary infection and ulceration can occur.