Canadian study finds increase in ICU superbugs
An analysis of more than 8,000 isolates from Canadian intensive care units (ICUs) over 10 years shows a significant increase in the prevalence of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) and extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli, researchers from the University of Manitoba reported yesterday in the Journal of Antibacterial Chemotherapy.
From 2007 through 2016, 42,938 clinically significant bacterial and fungal isolates were collected from Canadian tertiary care centers as part of the CANWARD national surveillance study; 8,130 of the isolates came from ICUs. Of the 8,130 pathogens collected, 58.2%, 36.3%, 3.1% and 2.4% were from respiratory, blood, wound and urine specimens, respectively.
The top five organisms collected accounted for 55.4% of all isolates and included S aureus (21.5%), Pseudomonas aeruginosa (10.6%), E coli (10.4%), Streptococcus pneumoniae (6.5%) and Klebsiella pneumoniae (6.4%). The most active agents against gram-negative organisms were carbapenems, tigecycline, and piperacillin-tazobactam; against gram-positive organisms, the most active agents were vancomycin, daptomycin, and linezolid.
MRSA accounted for 20.7% of S aureus collected, with the proportion of CA-MRSA genotypes compared with healthcare-associated MRSA increasing in prevalence across the study (P < 0.001), from 15.3% in 2007 to 76.2% in 2016. Multidrug resistance (MDR) and extensive drug resistance (XDR) was identified in 26.3% and 14.9% of E coli isolates, with both phenotypes demonstrating a significant increasing trend (P < 0.0001). In addition, 10.1% of E coli were identified as ESBL producers, with the proportion of ESBL-producing E coli rising from 2.5% in 2007 to 11.6% in 2016. MDR and XDR Enterobacter cloacae and K pneumoniae also increased significantly over time.
The authors of the study say the increase in ESBL-producing E coli, which could lead to increased use of carbapenems and increase selection pressure for the expansion of carbapenem-resistant Enterobacteriaceae, is a worrisome trend that must continue to be monitored.
Nov 29 J Antimicrob Chemother study
Study: Probiotics don't lower ESBL colonization risk in travelers to India
A small study by Danish researchers has found that the use of probiotics in people traveling to India did not lower the risk of colonization with ESBL-producing Enterobacteriaceae (ESBL-E). The findings appear today in Travel Medicine and Infectious Disease.
In the study, Danish travelers visiting India for 10 to 28 days were randomized to receive the probiotic species Lactobacillus Rhamnosus GG (LGG) or no probiotic at all. Because travelers to India are often colonized with ESBL-E or carbapenemase-producing Enterobacteriaceae (CPE) upon return, the researchers wanted to see if LGG could have a preventive effect on colonization.
Thirty-one travelers were randomized to the LGG group and 30 to the control group. Rectal swabs and questionnaires were collected from participants before travel, immediately after, and 6 months after return, and the swabs were tested for the presence of ESBL-E and CPE. Before traveling, 6 of 50 (12%) participants were colonized with ESBL-E. Immediately after return, 41 of the 44 (93.2%) who were not colonized before travel were colonized, and 6 months after return 11 of 36 (30.6%) were still colonized.
While the study found no statistically significant difference in the colonization rate between the LGG group and the controls, the researchers say the study confirms the high incidence of colonization with ESBL-E associated with travel to India. The investigators detected no CPE.
Nov 30 Travel Med Infect Dis abstract