Antibiotic-resistant bacteria among children in U.S. on the rise

"Some infections in children that have typically been treated with oral antibiotics in the past may now require hospitalization, treatment with intravenous drugs, or both, as there may not be an oral treatment option available," said Dr. Latania K. Logan, lead author of the study and an assistant professor of pediatrics and pediatric infectious disease specialist at Rush University Medical Center.

The team of researchers led by Logan analyzed resistance patterns in approximately 370,000 bacterial cultures from pediatric patients collected nationwide between 1999 and 2011.

They found that the prevalence is increasing in a resistant type of bacteria, which produces a key enzyme, extended-spectrum beta-lactamase (ESBL), that thwarts many strong antibiotics, making them ineffective.

Another indicator of ESBL prevalence, susceptibility to third-generation cephalosporins -- an important class of antibiotics used to treat many infections -- was also measured.

The prevalence of ESBL-producing bacteria increased from 0.28 percent to 0.92 percent from 1999 to 2011; resistance to third-generation cephalosporins increased from 1.4 percent to 3.0 percent. ESBLs were found in children across the country of all ages, but slightly more than half of the bacteria with this resistance were from those 1-5 years old. Nearly three-quarters (74.4 percent) of these bacteria were resistant to multiple classes of antibiotics.

While the overall rate of these infections in children is still low, ESBL-producing bacteria can spread rapidly and have been linked to longer hospital stays, higher health care costs, and increased mortality, the study authors noted. In a 2013 report, the Centers for Disease Control and Prevention called ESBLs a "serious concern" and a significant threat to public health.

"These antibiotic-resistant bacteria have traditionally been found in health care settings but are increasingly being found in the community, in people who have not had a significant history of health care exposure," Logan said. "In our study, though previous medical histories of the subjects were unknown, 51.3 percent of the children with these infections presented in the outpatient or ambulatory setting."

"Physicians should obtain cultures for suspected bacterial infections to help determine which antibiotics are best," said Logan.

Additional drug development, keeping younger patients in mind, is also needed. "The overwhelming majority of current research for new pharmaceuticals against antibiotic-resistant organisms are in adults," said Logan.

"More research is needed to define risk factors for these infections in children, their prevalence in different settings, and their molecular epidemiology," Logan said. A companion study by several of the same researchers is now available online in the Journal of the Pediatric Infectious Diseases Society, which suggests that children with neurologic conditions are at higher risk for infections caused by ESBL-producing bacteria.