The rate of antibiotic-resistant Gram-negative bacterial infections in children is increasing in inpatient and outpatient settings, a study reports.
The prevalence of third-generation cephalosporin-resistant (G3CR) bacteria increased from 1.39% in 1999-2001 to 3% in 2010-2011, wrote Latania K. Logan, MD, of Rush University Medical Center in Chicago, and her co-authors online in the Journal of the Pediatric Infectious Disease Society.
The prevalence of extended-spectrum B-lactamase-producing (ESBL) bacteria increased from 0.28% to 0.92% in the same time frame, the authors said.
"Blood and respiratory cultures showed a higher proportion of G3CR and ESBL, rising in prevalence across patient settings, U.S. regions, and pediatric age groups represented in the data," the authors said. "Presentation in the ambulatory settings is common."
Respiratory G3CR and ESBL prevalence increased from 7.01% and 2.2% in 1999-2001 to 16.2% and 6.3% in 2010-2011 (P<0.01), respectively, they said.
The researchers used regional and national data from The Surveillance Network Database-USA, a network that includes close to 300 clinical laboratories. The analysis included all isolates of Klebsiella pneumoniae, Escherichia coli and Proteus mirabilis from pediatric patients between the ages of 1 and 17. All specimens were collected in outpatient and inpatient settings, including the intensive care unit, between January 1999 and December 31, 2011.
Out of 368,398 pediatric isolates analyzed, 1.97% (7,255) were identified as G3CR and 0.47% (1,734) were identified as ESBL.
The majority of isolates were E. coli (67.8% for G3CR and 65.2% for ESBL).
"Increasing resistance in Enterobacteriaceae is an emerging public health threat, underscored by recent well-publicized outbreaks and national reports," the authors said.
Resistance to third-generation cephalosporins, they said, "is particularly worrisome when caused by ESBLs, as the spread of these enzymes is plasmid-mediated and can be transferred to other Gram-negative species."
The findings in this paper are consistent with previous reports of the same data in adults, which also report an upward trend, the authors said. The prevalence rate for adults was higher, ranging from 5% to 13% over the same time period used to assess the data in children.
ESBLs have been more of a problem in adult populations, possibly due to adults' greater exposure to hospitalization and indwelling devices, among other factors related to greater healthcare intervention. The clinical risk factors for children may be similar, the authors said; however, the data are limited.
"Additional studies in children to assess risk factors for acquisition, prevalence in ambulatory and long-term healthcare facilities, and the molecular epidemiology of ESBL-producing bacteria are warranted," the authors said.
The study had several limitations. Because the data came from laboratory surveillance, the researchers couldn't account for clinical characteristics or distinguish between confirmed infection and colonization.
Patient location entered in laboratory information systems may not, in fact, correspond to the clinical setting where the patient received care. And though all laboratories applied CLSI methods, "susceptibility testing was not centralized," the authors said.
Interpretive susceptibility breakpoints for cephalosporins were lowered in January 2010, which might have increased cephalosporin resistance for isolates after that date. And the analyzed data does not include Klebsiella oxytoca, which often occurs alongside Klebsiella pneumoniae.
The authors disclosed no relevant relationships with industry.
Journal of the Pediatric Infectious Diseases SocietySource Reference: Logan L, et al "Extended-spectrum b-lactamase-producing and third-generation cephalosporin-resistant enterobacteriaceae in children: Trends in the United States, 1999-2011" J Pediatr Infect Dis Soc 2014: 1-9.