Tuesday, March 02, 2004

Bacteria Run Wild, Defying Antibiotics

new chapter in the continuing story of antibiotic resistance is being written in doctors' offices across the country, as a group of common bacteria rapidly becomes resistant to the antibiotics that have been used to treat them for decades.

The bacteria are called Staphylococcus aureus, or staph for short. Staph are the most common cause of skin infections like boils and can also cause lung infections, bloodstream infections and abscesses in the body's internal organs.
Clusters of Staphylococcus aureus bacteria, a common cause of skin, lung and bloodstream infections.

In hospitalized patients, infections caused by antibiotic-resistant staph have been common for years. Among healthy people, though, antibiotic resistance in staph has not been a big problem. Since the 1970's, doctors have routinely, and successfully, treated staph infections in healthy patients with penicillin-like drugs.

Not anymore. Office doctors who follow this practice now may find their patients getting sicker instead of better.

Over the last year, Dr. John Gullett, an infectious disease specialist in Abilene, Tex., has grown accustomed to getting calls for help from local doctors who have used the usual antibiotics to no effect.

One doctor treated a high school football player "built like Charles Atlas" with a standard oral antibiotic for a little boil in the groin. Even though the teenager was the picture of health, the antibiotic did not work.

The boil, caused by resistant staph, grew into an large abscess tracking into the leg, and the patient got sicker and sicker. Only when Dr. Gullett treated him with an intravenous antibiotic generally reserved for desperately ill hospitalized patients did he turn the corner.

Had the patient's first doctor been aware that the infection was caused by resistant staph and chosen a different oral antibiotic, the entire episode might have been milder.

Resistant staph, Dr. Gullet said, are "more invasive and more pervasive" than the strains most primary care doctors are used to treating.

Dr. Gonzalo Ballon-Landa, an infectious disease specialist at Mercy Hospital in San Diego, said he was "very concerned about what we are seeing."

Dr. Ballon-Landa has treated clusters of infections from resistant staph in such disparate groups as prisoners, homeless people, student nurses and football players.

"Most doctors are just not aware of this," said Dr. Bonnie Bock, an infectious disease specialist in Newport Beach, Calif., who has treated resistant staph infections in groups of secretaries, surfers and gay men.

Dr. Bock estimated that about two-thirds of the large staph abscesses she saw in her office now were caused by the resistant bacteria.

Over all, staph infections are extremely common and often quite minor. Even staph abscesses, if they are drained properly, may heal without requiring any antibiotics at all. The new resistant staph can be treated with several common antibiotics — just not the ones doctors are accustomed to using.

Still, the experts say that some infections caused by the new resistant staph are unexpectedly aggressive, and delays in starting the right antibiotics may be life-threatening.

"Staph infections are such a common problem that the emergence of infections resistant to common antibiotics has important public health implications," said Dr. Daniel B. Jernigan, an epidemiologist at the federal Centers for Disease Control and Prevention.

But the infections are so common that they are not reportable to the local or federal public health authorities. Because of this, detective work to explain the appearance of the new resistant staph in this country and track its progress is just beginning.

The resistant staph was first recognized in the United States among children in Chicago in the mid-1990's. In 1999, the disease control centers reported that four children in the Midwest had died of infections with the new staph. Three of them had initially been treated with the wrong antibiotics.

In the last several years, clusters of infections with the resistant staph have been reported in jails and prisons in states around the country, including California, Texas, Pennsylvania and Georgia. Clusters of skin infections have also been reported among athletic team members and military recruits.