A 16-year-old male high school student requests treatment for scattered papules on his legs that have been present for several weeks. He plays football and states that several sites have become traumatized and are at times painful. He is unaware of similar lesions affecting his girlfriend, other family members, or teammates. Examination reveals scattered flesh-colored papules, some of which show slight crusting and purulence.
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Molluscum contagiosum (MC) is a benign skin condition caused by a virus that is known to affect only humans. The MC virus causes skin lesions characterized by dome-shaped flesh- to pink-colored papules measuring 2 to 5 mm in diameter. The papules are generally umbilicated and contain a central caseous plug.
The MC virus is a member of the Poxviridae family of which 4 types have been identified. Type 1 predominates in the general population,1,2 whereas type 2 is the cause of the majority of infections in people with HIV.
MC is most common in whites aged younger than 5 years and young adults, with a male preponderance. The peak among the pediatric age group correlates with casual contact, whereas the peak in young adults is ascribed to sexual contact.3,4 The prevalence rate of MC in people with HIV is reported to be between 5% and 18% and is highest in those with low CD4 counts.
In healthy people, MC is generally self-limiting and resolves within several months; however, trauma or scratching may lead to secondary infection. Therapeutic options for MC can be divided into broad categories that include benign neglect, lesion removal by curettage or liquid nitrogen, or the application of topical medicaments that are either caustic or promote localized immune enhancement. Curettage and cryosurgery are effective and usually well-tolerated in adults but less so in children. Extensive cases of MC may warrant a combined approach.5
Michael Stas, DPM, is a podiatry-dermatology fellow at St. Luke’s University Hospital in Bethlehem, Pennsylvania, and the DermDox Dermatology Center in Hazleton, Pennsylvania. Stephen Schleicher, MD, is an associate professor of medicine at the Commonwealth Medical College in Scranton, Pennsylvania, and an adjunct assistant professor of dermatology at the Perelman School of Medicine at the University of Pennsylvania in Philadelphia. He practices dermatology in Hazleton, Pennsylvania.
- 1. Bhatia AC. Molluscum Contagiosum. Medscape Drugs & Diseases. http://emedicine.medscape.com/article/910570-overview. Updated April 22, 2016. Accessed January 4, 2017.
- 2. Scholz J, Rosen-Wolff A, Bugert J, et al. Epidemiology of molluscum contagiosum using genetic analysis of the viral DNA. J Med Virol. 1989;27:87-90.
- 3. Laxmisha C, Thappa DM, Jaisankar TJ. Clinical profile of molluscum contagiosum in children versus adults. Dermatol Online J. 2003;9:1.
- 4. Dohil MA, Lin P, Lee J, Lucky AW, Paller AS, Eichenfield LF. The epidemiology of molluscum contagiosum in children. J Am Acad Dermatol. 2006;54:47-54.
- 5. Nguyen HP, Franz E, Stiegel KR, Hsu S, Tyring SK. Treatment of molluscum contagiosum in adult, pediatric, and immunodeficient populations. J Cutan Med Surg. 2014;18:299-306.