Molluscum contagiosum is a contagious skin infection caused by a poxvirus that causes pink or white, dome-shaped, and smooth or waxy bumps to form.
This infection is caused by a poxvirus.
The bumps can appear on many parts of the body and usually are not itchy or painful.
The diagnosis is typically based on the appearance of the bumps.
Bumps that do not go away by themselves can be treated with creams or can be removed by freezing, burning, and/or cutting.
The virus that causes molluscum is contagious. It spreads by direct physical contact with an infected person or with objects such as towels or sponges that have been touched by an infected person. Molluscum contagiosum also can spread from one person to another by sexual contact. The virus can spread in water, such as in pools, baths, or saunas.
Infection may cover larger areas of skin, and bumps tend to be larger in people who have a weakened immune system such as those with HIV/AIDS or who use corticosteroids or receive cancer chemotherapy.
This infection is common among children.
Symptoms of Molluscum Contagiosum
Molluscum contagiosum can infect any part of the skin except the palms of the hands and soles of the feet.
The bumps are usually less than 1/4 inch (about 0.2 to 0.5 centimeters) in diameter, shaped like a dome, and have a tiny dimple in the center.
In children, the bumps occur most commonly on the face, trunk, arms, and legs. In adults, the bumps occur most commonly on the penis, vulva, or in the pubic area.
The bumps usually are not itchy or painful and may be discovered only coincidentally during a physical examination. However, the bumps can become very inflamed (resembling a boil) and itchy as the body fights off the virus. This inflammation may indicate that the bumps will soon disappear.
This image shows scattered bumps of molluscum on the trunk of a toddler.
Image courtesy of James G.H. Dinulos, MD.
The photo shows bumps of molluscum contagiosum.
© Springer Science+Business Media
In this child with human immunodeficiency virus (HIV) infection, the bumps of molluscum contagiosum cover a wide area and involve the face.
© Springer Science+Business Media
Diagnosis of Molluscum Contagiosum
A doctor's evaluation
Doctors base the diagnosis of molluscum contagiosum on its appearance.
If doctors are unsure of the diagnosis, they may remove a sample of material from the skin and examine it under a microscope.
Treatment of Molluscum Contagiosum
Treatments applied to or injected into the bumps
Procedures to remove the bumps
Most bumps disappear spontaneously in 6 to 9 months, but they can remain for 2 to 3 years.
People with bumps in the groin area that were presumably acquired sexually should be treated to prevent spread of the infection. Otherwise, no treatment of molluscum contagiosum is needed unless the growths are disfiguring or otherwise bothersome.
The bumps also can be treated by freezing (cryotherapy), burning with a laser or electric current, or removing their core with a needle or sharp scraping instrument (curette).
Other treatments include injection of Candida antigen into a bump and photodynamic therapy. Candida antigens are proteins that come from the Candida yeast. When injected into the bump, they cause an immune response that fights against the virus. Similarly, interferons are proteins that trigger immune cells to attack the virus. In photodynamic therapy, a chemical preparation is applied to the skin and then artificial light is applied to the bumps. The light activates the chemical to produce a form of oxygen that kills the virus causing the bumps.
In people with HIV infection who develop molluscum contagiosum, treatment of the HIV infection with antiviral medications is often necessary to allow the molluscum contagiosum to resolve.
Children do not need to be excluded from school or day care. However, their bumps should be covered to reduce the risk of spread to others.