The rise of drug-resistant bacteria has made some deadly diseases all the more lethal, but it is also having an impact that is sure to dismay teenagers: making it harder for dermatologists to treat acne.

Resistance to antibiotics among the bacteria that contribute to acne formation is not new, but the problem has grown steadily to a point where doctors say they are running out of treatment options for patients with more serious acne. Doctors and researchers are now working to come up with new ways of treating acne, from combining antibiotics with chemical compounds to using light therapies.

"We have to," said Ngoc Pham, a Kaiser Permanente dermatologist in Santa Clara. "When things get difficult, we have to be innovative."

Acne is caused in part by the colonization of hair follicles by the bacteria P. acnes. The more oil the follicle has, the more bacteria are attracted to it.

"Once they reach a certain threshold, it's just a haven for bacteria," Pham said.

Many people with acne don't have to worry about resistance, typically only having to use over-the-counter products that contain ingredients such as salicylic acid. But for the 15 to 20 percent of teenagers whose acne is deemed moderate to severe, either topical or oral antibiotics are a crucial component of a treatment regimen.

2 possible forces

If a patient's acne is not responding to antibiotics, two dynamics may be at play: one at the individual level and one at the population level, said Eleni Linos, an assistant professor of dermatology at UCSF. An individual who has been exposed to a lot of antibiotics in the past may be more likely to have developed drug resistance, Linos said. But more broadly, the bacteria overall have grown more defiant in recent decades.

When a patient uses antibiotics, the drugs kill off the sensitive bacteria, but leave the resistant ones untouched, allowing them to multiply freely.

"We're essentially creating a world where more of these resistant ones can proliferate and grow," Linos said.

To combat resistance, doctors have turned away from prescribing antibiotics alone. They have found that combining oral antibiotics with benzoyl peroxide or retinoids not only reduces the risk of resistance, but also is a more effective treatment for severe cases.

Topical benzoyl peroxide, for example, focuses on all the bacteria on the skin's surface - including the resistant ones - while oral antibiotics go after the bacteria deeper within the follicle. Retinoids, which are compounds similar to vitamin A, help prevent pores from becoming clogged.

Doctors suggest taking antibiotics for only a few months at a time, avoiding using both oral and topical antibiotics simultaneously, and not increasing dosages if the drugs appear not to be working.

Treatments that do not include antibiotics are also being developed. One that has shown promise involves using lights and lasers to shrink pores and slash oil and bacteria production. The problem is that the treatment, photodynamic therapy, remains very expensive.

There are so many types of acne that coming up with the right regimen for a specific patient is "like an art," Pham said.

Nicole Benoist, 24, of Alviso, for example, had been struggling with acne since middle school and said she tried "pretty much anything you can think of" for over-the-counter treatments.

"It was pretty tough, because I went to a small school and I was probably the only one with acne issues," she said of her middle school.

Oral, topical remedies

But over the summer, Pham recommended trying a therapy of oral antibiotics and topical retinoids, and Benoist said her skin has finally started to clear up.

"You have to try various modalities because everyone is different," Pham said.

Benoist has also undergone two rounds of photodynamic therapy and said she noticed some "incredible" results.
