Orioles pitcher Mike Mussina was sidelined with a wart on his finger. (Rich Lipski/TWP)

By Sally Squires
Washington Post Staff Writer
Tuesday, May 5, 1998; Page Z09

When the Baltimore Orioles ace pitcher Mike Mussina was sidelined recently with a troublesome recurring wart on his index finger, he joined the ranks of millions of Americans who suffer from this common, and often persistent, skin malady.

"Patients get really frustrated if the wart keeps coming back," said Timothy Berger, chief of the dermatology clinic at the University of California at San Francisco and a spokesman for the American Academy of Dermatology. "People say, 'Why can't you just get rid of it?' But it's not always so simple."

In Mussina's case, the wart was located on the palm side of the tip of his right index finger -- precisely in a location that got irritated every time he gripped the ball to pitch. He returned to the lineup Sunday and pitched more than seven innings in the Orioles' shutout win over the Minnesota Twins. But as is the case with one in 10 people, Mussina's wart did not respond to the first several rounds of treatment with liquid nitrogen and surgery.

Warts are caused by a human papilloma virus (HPV), a family of microbes found "pretty much everywhere in the environment," Berger said. "Seventy percent of the population has been exposed."

Only about 1 percent of those infected develop warts, but they occur frequently enough to account for at least 10 percent of all visits to dermatologists, according to the American Academy of Dermatology.

There are between 80 and 100 different strains of the human papilloma virus, and different strains cause warts in different parts of the body. Plantar warts thrive on the bottom of the feet and are common among those who go barefoot in locker rooms. Genital warts are sexually transmitted and are closely linked to the development of cervical cancer in women. Flat warts often appear in large clusters of 20 to 100. They occur on the face.

And then there is the common wart, the variety that thrives on hands, especially around nails and on the palm side of fingertips. It is this type that put the Orioles' Mussina on the disabled list. "I'm surprised that it doesn't happen more often," said Carl Beutner, director of the Human Papilloma Virus Clinic at the University of California at San Francisco. "Anyone who has sweaty hands is prone to warts, and athletes are sweaty a lot."

Athletes also share equipment that can help spread the human papilloma virus. For example, pitchers use rosin bags to coat their hands with powder to give them a better grip on the ball. "You could transmit warts from the rosin bags," Beutner said.

Warts are small raised bumps that generally are the same color as the skin of the person they infect. In order for the human papilloma virus to take up residence, there must be a break in the skin. Since hands and feet are the most likely to be cut or wounded, they are the places where warts are most likely to develop. The variety of the virus that causes common warts thrives in the epidermis, the outer layer of the skin, where it produces the characteristic bump.

Common warts often have a hard surface and may contain tiny spikes that reach down into the skin as well as minuscule black dots. "People call these roots, but they are actually blood vessels that run up and down in the wart," Berger said.

Doctors can identify most warts by sight. But if there is any question about the diagnosis, they snip the roots to confirm that the bump is a wart. "If you trim that down, you will see a bleeding point [in warts], and that is very helpful in making the diagnosis," Berger said.

It is not well understood why some people develop warts while others don't.. Susceptibility to warts seems to run in families. Studies suggest that what separates those who are resistant to warts from others is the immune system's inability to identify and remove the human papilloma virus from the body. "It's probably like other infectious diseases," Berger said. "Different people have a different capacity to deal with it."

Between half and two-thirds of warts vanish without medical treatment when the body's immune system correctly targets the virus. "As long as you are sure it's a wart, there is no need to rush off and see the doctor immediately," Beutner said, although physicians often recommend confirming the diagnosis to rule out other diseases, such as skin cancer.

For those warts that fail to disappear on their own or for warts that develop in places where they are chronically rubbed or irritated, such as Mussina's, there are several treatment options.

Usually doctors first try brief blasts of liquid nitrogen on the wart. The liquid nitrogen treatment, which stings for a few seconds, freezes the area around the wart. It does not affect the virus, but "it's a controlled way to damage the skin around it and make a blister," Berger said.

The freezing cleaves the wart from the middle layers of the skin and sets the stage for it to fall off. But it often takes more than one treatment to be effective: A 1995 team of British researchers reported that one round of liquid nitrogen cured warts in up to 45 percent of cases within three months of therapy.

A second approach is to apply liquid solutions to the wart. Commonly used preparations are salicylic acid and cantharidin, a solution made from the blister beetle. Salicylic acid is available in nonprescription products such as Compound W, which can be painted on the wart or applied via adhesive bandages. It takes multiple applications over a period of weeks and sometimes months to remove the wart. Like liquid nitrogen, salicylic acid causes a chemical change that produces a blister and helps cause the wart to fall off.

"The advantages are that this therapy is painless and can be used to treat children," Berger said.

Some doctors also recommend treatment with chemical sensitizers, such as squaric acid or dinitrochlorobenzene, an approach that grew out of a Native American remedy of rubbing poison ivy on warts. Just as exposure to poison ivy or poison oak stimulates an allergic reaction in most people, so does exposure to these chemicals. The result can jump-start the immune system into attacking the wart.

Hypnosis is another treatment that has been shown in controlled trials to be effective against warts, particularly in children. Studies have found that hypnosis cures warts in 27 to 55 percent of cases, although how it works is not yet known. "The suggestion is that it acts through the brain and nervous system, which can affect the immune system," Berger said. The theory is that hypnosis stimulates the brain to destroy the wart.

Surgery is also an option -- one that Mussina has also tried. Doctors numb the area with a local anesthetic and then either use a scalpel to pop out the wart from the skin or a laser to vaporize it. Bleeding is minimal, but doctors caution that there is a risk of scarring. Another drawback is that surgery does not eliminate the virus from the skin, where it can remain to form another wart.

As for the numerous folk remedies that have been used for centuries to treat warts, there is no scientific evidence that any of them are effective.