Molluscum contagiosum

Molluscum contagiosum: Overview

Molluscum (muh-luhs-kum) contagiosum (kən-tā-jē-ō-səm) is a common skin disease. It is caused by a virus. This virus easily spreads from person to person.

People can get molluscum by sharing towels and clothing. Wrestlers and gymnasts may get it from touching infected mats. Skin-to-skin contact also spreads the virus.

Often the only sign of molluscum is pink or flesh-colored bumps on the skin. These bumps can appear anywhere on the skin.

Most people get about 10 to 20 bumps on their skin. If a person has a weakened immune system, many bumps often appear. People who have AIDS can have 100 or more bumps.

Whenever you can see the bumps on the skin, molluscum contagiosum is contagious.

Molluscum contagiosum: Signs and symptoms

Bumps on the skin can be  the only sign that a person has molluscum contagiosum. These bumps often appear about 7 weeks after being exposed to the virus that causes molluscum. Sometimes, the bumps do not appear for many months.

When the bumps appear on the skin, they often:

• Begin as small, firm, dome-shaped growths.
• Have a surface that feels smooth, waxy, or pearly.
• Are flesh-colored or pink.
• Have a dimple in the center. The dimple may be filled with a thick, white substance that is cheesy or waxy.
• Are painless, but some bumps itch.
• Turn red as the person’s immune system fights the virus.
• Appear on other areas of the body after a person scratches or picks the bumps. Scratching or picking can spread the virus.

In adults, the bumps often appear on the face, neck, armpits, arms, and hands. Other common places for bumps to appear are the genitals, abdomen, and inner thighs. Adults often get molluscum contagiosum through sexual contact.

If a person has a disease that weakens the immune system, such as AIDS, the bumps can grow very large. A person may have 100 or more bumps on the face alone.

Molluscum contagiosum: Who gets and causes

Who gets molluscum contagiosum?

This skin disease is most often seen in children. People who live in a tropical climate also are more likely to get molluscum. The virus thrives in a warm, humid place. Having atopic dermatitis, the most common type of eczema, also increases the risk of getting molluscum contagiosum.

When a person has a weak immune system due to a medical condition such as AIDS or treatment for cancer, the person can get a serious case of molluscum contagiosum.

What causes molluscum contagiosum?

A virus causes molluscum. There are 2 ways to get this virus:

1. Touch something infected with the virus. You can get molluscum by using an infected towel. You can get it from touching infected clothing or toys. Wrestlers and gymnasts get it from touching infected mats.
2. Have direct skin-to-skin contact. Children often get molluscum because they have lots of direct skin-to-skin contact with others. People who participate in contact sports such as wrestling get molluscum from the direct skin-to-skin contact. Teens and adults often get the virus through sexual contact.

Once infected with the virus, a person can spread the virus to other parts the body. Scratching or picking at bumps on the skin and then touching skin that does not have bumps can spread the virus and cause new bumps. Your dermatologist may call this self-re-infection.

Molluscum contagiosum: Diagnosis and treatment

How do dermatologists diagnose molluscum contagiosum?

A dermatologist can often diagnose molluscum contagiosum by looking at your skin. Sometimes molluscum looks like another skin condition. The bumps can look like warts, chickenpox, and even skin cancer. If this happens, your dermatologist will scrape off a bit of infected skin, so it can be examined under a microscope.

How do dermatologists treat molluscum contagiosum?

When a child gets this skin condition, researchers have found that the skin often clears on its own. Clearing takes about 12 to 18 months. In many cases, children are not treated because treatment can have unwanted side effects for a child.

While molluscum can clear on its own, treatment has benefits. Treatment helps to prevent the virus that causes molluscum from:

• Spreading to other parts of your body
• Infecting other people
• Growing out of control in people who have a weakened immune system

For each patient, a dermatologist considers whether treatment is appropriate. If treatment is recommended, your treatment plan may include one or more of the following:

Procedures: Your dermatologist can perform these during an office visit:

• Cryosurgery: The dermatologist freezes the bumps with liquid nitrogen.
• Curettage: The dermatologist uses a small tool called a curette to scrape the bumps from the skin.
• Laser surgery: A dermatologist uses a laser to target and destroy the bumps. This can be an effective treatment for people who have a weakened immune system.
• Topical (applied to the skin) therapy: Your dermatologist can apply various acids and blistering solutions to destroy the bumps. These work by destroying the top layers of the skin. Tricholoracetic acid is often used to treat people who have a weak immune system and many bumps.

When a patient has many bumps or large bumps, a dermatologist may need to repeat a procedure every 3 to 6 weeks until the bumps disappear. These procedures cause some discomfort.

Medicines you apply at home: Medicines that your dermatologist may prescribe for you to use at home include:

• Imiquimod: This medicine is applied to the bumps. Imiquimod helps your immune system fight the virus. This is strong medicine. It also is used to treat stubborn warts and some skin cancers.
• Retinoid or antiviral medicine applied to the skin: Patients apply this medicine to the bumps as instructed.

While treating molluscum, it is normal for new bumps to appear as others fade.

Outcome

If a person with a healthy immune system opts not to treat molluscum, the bumps will eventually go away on their own without leaving a scar. Until the bumps go away, the person is contagious.

When  you choose to treat molluscum, you may get new bumps for as long as 6 months after you start treatment. Most people, however, have complete clearing in 2 to 4 months. It's important to remember that until the bumps clear, the infected person can give molluscum to others.

If a person has AIDS or another disease that weakens the immune system, the bumps will not go away without treatment — and the bumps can be a challenge to treat. Dermatologists often combine treatments to offer these patients some clearing. Complete clearing may not be possible.

Dermatologists offer the following tips to their patients who have molluscum contagiousum — or think that they may have this skin condition:

If you think you have molluscum contagiosum, make an appointment to see a dermatologist. It is important to get an accurate diagnosis. Sometimes what looks like molluscum contagiosum can be warts or even skin cancer.

Treatment for molluscum contagiosum helps to prevent this disease from spreading.

Take action so that you do not spread the disease. It is possible to spread this disease to other parts of your body and to other people. When bumps are visible, you can spread molluscum contagiosum. You can prevent spreading this disease by:

• Trying not to scratch or pick at the bumps. Covering the bumps with a bandage may help.
• Not participating in sports such as wrestling, gymnastics, and swimming.
• Not using locker rooms.
• Not sharing towels, washcloths, clothing, and other personal items.
• Not shaving skin that has bumps.
• Not having sex.

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Reference:

Rush J and Dinulos JG. “Childhood skin and soft tissue infections: new discoveries and guidelines regarding the management of bacterial soft tissue infections, molluscum contagiosum, and warts.”Curr Opin Pediatr. 2016; 28(2):250-7.