Bloodstream infections (BSIs) are considered as a major cause of morbidity and mortality all over the world. The purpose of this study was to explore the distribution and antimicrobial resistance trends of pathogens causing BSIs at a large tertiary-care hospital in Henan province, east-central China.
In this surveillance study, blood culture specimens were routinely taken from patients with fever or suspicion of sepsis from 2010 to 2019 at the First Affiliated Hospital of Zhengzhou University. Identification of organisms was carried out using the VITEK 2 Compact system and/or the VITEK MS system. Antimicrobial susceptibility tests were carried out by the minimum inhibitory concentration (MIC) method and/or the disk diffusion according to Clinical & Laboratory Standards Institute guidelines.
A total of 18180 strains were isolated from blood culture specimens, the most common pathogen was E. coli (21.6%), followed by CoNS (coagulase negative staphylococci, 18.8%), K. pneumoniae (13.0%), S. aureus (6.6%), E. faecium (5.0%), A. baumannii (4.4%), and P. aeruginosa (3.8%). The resistance rates of E. coli to ceftazidime, cefotaxime, cefepime and aztreonam showed a significant declined trend, and the frequency of carbapenem-resistant E. coli was below 6.0% over time. It is noteworthy that the proportion of carbapenem-resistant K. pneumoniae exhibited sharp upward trend during the ten years (from 6.7% to 56.7%). The prevalence of carbapenem-resistant A.baumannii has remained at a high level (>75%). In contrast, the resistance rates for P. aeruginosa against all tested agents were lower than 25%, and the resistance rates to aminoglycosides and fluoroquinolones showed a significant downward trend. The frequency of methicillin-resistant CoNS maintained a high level over the past decade (>70%), however, the isolation rate of MRSA ranged from 58.0% to 34.9%, showed a significant decline.
It was particularly noteworthy that the dramatic and consistent increase in carbapenem-resistance in K. pneumoniae during the 10-year surveillance period and effective infection control measures and stewardship efforts should be taken to prevent the spread. Our results indicate the the importance of active surveillance for bacterial etiology and their antibiotic resistance causing BSIs.

Copyright © 2021. Published by Elsevier Ltd.