Drug-resistant Bacteria Shifting the Treatment of Acne


As the bacteria that causes acne develops more of a resistance to drugs used to treat it, skin care professionals and dermatologists are increasingly needing to look elsewhere for ways to solve this skin issue.

It sounds like the stuff of teenage nightmares: super strong, freakishly clever, mutant acne. But dermatologists say the bacteria that causes acne is increasingly developing resistance to some commonly prescribed antibiotics, including tetracycline and erythromycin. And while the superbug MRSA is a widely known threat in the general medical community, some patients are surprised to learn that the P. acnes bacterium is equally capable of rebelling against drugs and developing superpowers.

“There’s been so much attention to MRSA and other kinds of resistant bacteria, which truly can kill you, whereas acne doesn’t kill you,” says Dr. Alan Fleischer, a professor and chair of dermatology at Wake Forest University School of Medicine. “And yet we doctors see patients who have resistant acne, and we do need to be cognizant of changes. The bacteria are changing, are adapting and becoming resistant.”

Antibiotics are one of the most frequently prescribed treatments for acne. They target the bacteria and inflammation, and often are key in clearing up the patient’s skin. But as antibiotic-resistant acne becomes a growing concern, dermatologists are moving away from using antibiotics as a primary weapon against acne, fearing that the long-held go-to treatments may be contributing to communal antibiotic resistance.

If they do prescribe antibiotics, it may be for only a limited time, usually a few months, and it's often combined with another medication that can lessen the drug resistance. Previously, patients might have continued on antibiotics for years. “The strong survive, the mutants survive and they become resistant,” says Dr. Jonette Keri, a Miami dermatologist.

Public health threat?

While drug-resistant acne can be devastating, the real danger is that it contributes to deadly drug-resistant staph infections. “The dangerous thing about putting zillions of folks on antibiotics is that this pressures bacteria to develop resistance methods,” says Dr. Peter Lio, a Northwestern University dermatologist. “So while the acne bacteria almost never causes life-threatening infection, the ways that it can be resistant to our antibiotics can be passed over to bacteria that can cause life-threatening infection, which means that our only weapons against the bad guys suddenly do not work anymore. If it became bad enough, it would be like the days before antibiotics, when infection was a common cause of death.”

Acne is a common teenage ailment, afflicting about 75–90% of teens. Even adult acne may be more common than many realize, with about 50% of adults suffering from acne at some degree, dermatologists say. “Acne is a really tough disease,” Lio says. “We can make a big difference with many patients, but it’s a humbling disease; it brings people down. People can be incredibly depressed coming in, so our job is to do whatever it takes to make them better.”

Between 10–30% of acne patients harbor at least some resistant bacteria, dermatologists say. Few studies have been published about drug-resistant acne, but French researchers found in 2001 that more than 50% of the isolates of the bug P. acnes were resistant to erythromycin, a commonly prescribed antibiotic.

When the antibiotics stop working for a patient, the results are devastating. In most cases of drug resistance, the antibiotics initially work, and patients think their skin has finally cleared, maybe for good this time. Then, all of a sudden the acne comes back — in some cases, worse than ever before.

When antibiotics fail

About six months ago, 16-year-old Chris Fields started taking 500 mg of tetracycline once a day, every morning. A month later, his skin cleared and stayed that way for two months. He started to remember what it was like to look people in the face without privately agonizing that they were scrutinizing his.

“I had more self-confidence and stuff,” says Chris, a high-school sophomore who lives in Concrete, Washington. “When I’d go out in public, I’d actually look people in the eye, and not be so worried about how my face looks. Right now, that’s starting to slip away again.”

That’s because a few weeks ago, his acne started to come back. He’s not sure if it’s worse than it was before, or if he’s just imagining that it is, but either way, its presence couldn’t be more unwelcome: Prom is less than three weeks away.

He has a appointment with his doctor next week to figure out what went wrong, but from his own medical Googling and time spent on message boards such as acne.org, he expects he’s developed this antibiotic resistance. But maybe the strangest thing about this particular affliction is that patients never really know for sure that they have it at all. “Most people in private practice do not do a test,” says Keri, the Miami dermatologist. “If they thought [patients] were resistant, they might switch antibiotics or add topical treatment to the mix.”

The P. acnes bacterium can be tested for resistance, but that’s usually done only in clinical trials or study circumstances. When a patient stops responding to antibiotics, most dermatologists assume the bacteria have developed resistance, and doctors simply try something else.

A bevy of effective treatments

Bacteria, resistant or not, is only one contributer to the formation of a zit. Four things have to happen for people to get a pimple: First, oil increases in a pore. Second, the skin cells that line the pore get sticky from the extra oil, creating a clog in that pore. Third, bacteria feasts on all that oil and begin to overgrow. Finally, the body responds to the bacteria, causing the inflammation.

“The fact is, because acne is much more complicated than a simple infection, there really are a wide variety of other approaches that are very useful,” says Fleischer of Wake Forest University. Doctors found that combining benzoyl peroxide with an antibiotic counteracts the drug resistance. And there are plenty of other methods dermatologists use to attack acne, including using anti-inflammatory drugs such as retinoids and isotretinoin.

Fewer dermatologists now rely on antibiotics alone to treat acne. A recent University of Pennsylvania study found that people on antibiotics were about twice as likely to develop an upper respiratory tract infection. And a study Fleischer co-authored in 2005 found a significant shift from dermatologists prescribing antibiotic to non-antibiotic treatments.

When Fleishcher started his practice 20 years ago, erythromycin was the treatment he most commonly prescribed. “Now maybe I have one patient on it, maybe. [Acne] is not a life-threatening situation; it is a quality of life situation. Using drugs that don’t display drug resistance will allow us to make patients look and feel better,” he says.

By Melissa Dah, MSNBC.com, April 13, 2009



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