Staph faces a stronger opponent

At long last, there is more than one drug that can knock out antibiotic-resistant staph -- one of the deadliest and most common types of bacterial infection.

The additional firepower, a prescription antibiotic called daptomycin, comes at a time when it's sorely needed, according to research published in this week's New England Journal of Medicine. The journal reports that antibiotic-resistant staph is now the leading cause of skin infections seen in hospital emergency rooms. On average, the bug accounts for 59 percent of skin infections in the ER, the study found.

Local hospitals see such infections weekly, and outbreaks have been reported statewide among high school sports teams, at day-care facilities and in athletic clubs, among other places. Just a few years ago, antibiotic-resistant staph was rarely seen outside hospitals.

Most staph infections start in the skin but can quickly spread to the blood, bones and vital organs without proper treatment. Staph is responsible for as many as 2 million infections and 90,000 deaths each year, according to the Centers for Disease Control and Prevention.

"People don't really understand how severe it is, or that it's even around," said Michele Lee of Wakefield, whose son Kristian contracted antibiotic-resistant staph last summer.

Kristian, then 14, complained that his left heel hurt but had no obvious sore or wound. Doctors initially diagnosed him with a broken heel and sent him home in a cast. But within days, Kristian's fever shot up to 104 degrees, and his parents rushed him to the emergency room.

He ended up having surgery to drain and clean his infected heel, and was in and out of hospitals for a month. The infection invaded his bones and blood. Doctors tried four or five antibiotics on Kristian before starting him on vancomycin -- the medicine doctors have relied on for decades to kill antibiotic-resistant staph.

But the cure was almost as scary as the infection: The drug temporarily shut down Kristian's kidneys. He bounced back and is now healthy, Michele Lee said.

Now there's a proven alternative to the therapy Kristian received, researchers from Duke University Medical Center and elsewhere report.

The alternative, daptomycin, isn't a new medicine. It has been marketed in the United States since 2003 under the brand name Cubicin and prescribed for staph infections in skin. But doctors have been hesitant to use it to treat more serious staph infections in the bloodstream and heart.

Such infections can kill 80 percent of patients if not treated properly, and clinicians are unwilling to take a risk on a medicine they aren't sure works as well as the standard therapy, said Dr. Peter Leone, an infectious disease doctor who practices at UNC Hospitals in Chapel Hill. "Given how sick these folks are when they come in, you don't want to find out a week later that you made the wrong choice," said Leone, who is also an associate professor of medicine at UNC-Chapel Hill.

A study conducted by physicians at Duke and 43 other centers provides the first evidence that daptomycin is as effective as standard therapy at clearing staph infections of the bloodstream and heart.

But daptomycin, a liquid antibiotic given intravenously, was more effective at clearing antibiotic-resistant strains, researchers found. It cleared antibiotic-resistant bloodstream and heart infections in 44.4 percent of patients, while vancomycin, also an IV antibiotic, cleared just 31.8 percent. Daptomycin also caused less kidney damage than standard therapy, giving it another potential edge.

"If it can mitigate the damage to the kidneys, I'm all for it," said Ed Lee, Kristian's father.

The maker of daptomycin, Cubist Pharmaceuticals of Massachusetts, paid for the study.

"Ultimately, it gives the clinician more choices," said Dr. Vance G. Fowler Jr., an associate professor of infectious disease at Duke and lead author of the journal article on daptomycin. "If a patient can't tolerate [vancomycin] or is failing on it, we now have an alternative."

Based on the daptomycin trial's results, the U.S. Food and Drug Administration has already approved the drug for use on bloodstream infections, also known as bacteremia, and heart infections. It is the first new drug to be approved for those conditions in more than 20 years, Fowler said.

Daptomycin isn't a perfect solution, however. In six of the 124 infected patients treated with the drug during the study, the staph strains developed resistance before treatment had finished.

Fowler said the finding points to the need for doctors to properly clean and drain infections rather than relying exclusively on drugs to resolve them. Many infections of antibiotic-resistant staph clear up after draining and cleaning alone.