Molluscum contagiosum

Injury	Disease	Nutrition	Poison

Symptoms	Surgery	Test	Special Topic

Molluscum contagiosum - close-up

Molluscum contagiosum - close-up of the chest

Molluscum on the chest

Molluscum, microscopic appearance

Molluscum contagiosum on the face

Molluscum contagiosum

Definition:

Molluscum contagiosum is a viral skin infection that causes raised, pearl-like papules or nodules on the skin.

Causes, incidence, and risk factors:

Molluscum contagiosum is caused by a virus that is a member of the poxvirus family.

This is a common infection in children. It is frequently seen on the face, neck, arm pit, arms, and hands but may occur anywhere on the body except the palms and soles.

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The virus is contagious through direct contact, as seen in children, but may spread by sexual contact. Molluscum is generally seen on the genitals as a sexually-transmitted disease.Early lesions on the genitalia may be mistaken for herpes or warts but, unlike herpes, these lesions are painless. Because molluscum produces no serious illness and is not of long-term public health significance, it has not been treated as other sexually-transmitted diseases. The importance is significant in the growing population of immunocompromised people with AIDS, who may have rapidly worse case of molluscum contagiosum.

Typically, the lesion of molluscum begins as a small papule which may become raised up to a pearly, flesh-colored nodule. The papule often has a dimple in the center (umbilication). These papules may occur in lines, where the person has scratched. Scratching or other irritation causes the virus to spread in a line or in groups (crops).

The papules are approximately 2 - 5 millimeters in diameter and painless. There is usually no inflammation and subsequently no redness unless the person has been digging or scratching at the lesions. In the mature molluscum, the top of the nodule may be opened with a sterile needle and a small waxy core can be seen and squeezed out of the lesion.

Molluscum contagiosum is a chronic infection and lesions may persist from a few months to a few years. These lesions ultimately disappear without scarring. (Unless there is excessive scratching, which may leave marks.)

References:

Cohen J, Powderly WG. Infectious Diseases. 2nd ed. New York, NY: Elsevier; 2004:2053-2056.

Kauffman CL. Molluscum contagiosum. eMedicine.January 6, 2005.Available online at http://www.emedicine.com/derm/topic270.htm Accessed October 31, 2005.