As science gets wiser, so do the bugs. The rates of drug-resistant bacteria infecting patients in the community and in the hospital have been increasing steadily in recent years, according to two new studies in the June 15 issue of Clinical Infectious Diseases.
Drug resistance in microorganisms has become a problem due in part to inappropriate prescribing and overuse of antibiotics. These drug-resistant "superbugs" can infect people and cause health problems that are difficult to address with the standard antibiotic regimens. One of the culprits is methicillin-resistant Staphylococcus aureus, or MRSA, an organism that was associated mainly with hospital-acquired infections, but is becoming increasingly common in the general community, as has been reported recently in the medical literature. It can cause problems ranging from skin infections to severe bloodstream infections and even death.
Researchers at the Baylor College of Medicine and Texas Children's Hospital conducted a three-year study of S. aureus infections in children. They found that among S. aureus isolates acquired in the community, the proportion of isolates that were MRSA had reached 76 percent in 2003. Over the preceding three years, the number of MRSA infections acquired in the community had more than doubled. The MRSA isolates caused skin and soft tissue infections in most cases, and more than 60 percent of these children were admitted to the hospital.
The rapid rise in pediatric community-acquired MRSA infections in Texas should raise red flags for health care workers everywhere. "There have been deaths related to this organism, although the vast number are skin and soft tissue infections," said Sheldon Kaplan, MD, lead author of the Texas study. He added that because of this "very dramatic increase" in MRSA infections, physicians should learn what percentage of staphylococcal isolates are drug-resistant in their own communities so they can monitor for increases and adjust treatment accordingly.
Prevention of MRSA infections mainly involves common sense. "If you get a cut or an abrasion, try to keep it clean and dry" and don't share towels or washcloths with others, Dr. Kaplan said. Most importantly, he added, "Wash hands, wash hands, wash hands."
And if regular drug-resistant bacteria weren't bad enough, some bacteria have become multidrug resistant (MDR). Researchers at the Beth Israel Deaconess Medical Center and Harvard Medical School studied the prevalence of bacteria resistant to three or more drugs over a six-year period. From 1998 to 2003, there was a significant increase in the incidence of patients carrying MDR bacteria when they were admitted to the hospital. Of the four species of MDR bacteria that the researchers examined, three of them--including Escherichia coli, a familiar bug that can cause urinary tract infections--were involved in the upswing.