AUTHOR=Duan Nan , Sun Liying , Huang Chenwei , Li Haixia , Cheng Bin 

TITLE=Microbial Distribution and Antibiotic Susceptibility of Bloodstream Infections in Different Intensive Care Units

JOURNAL=Frontiers in Microbiology

VOLUME=Volume 12 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2021.792282

DOI=10.3389/fmicb.2021.792282

ISSN=1664-302X

ABSTRACT=Background: Bloodstream infection (BSI) is an increasing public health concern worldwide, representing a serious infection with significant morbidity and mortality, especially in children and elderly. The predominant microbial distribution and antibiotic susceptibility were investigated among BSIs in the pediatric intensive care unit (PICU), surgical ICU (SICU), cardiac ICU (CICU), respiratory ICU (RICU) and geriatric ICU(GICU) in order to achieve more efficient and appropriate therapies for patients in various ICUs.
Methods:In this retrospective cross-sectional study, the blood specimens were collected from five different ICUs of Peking University First Hospital and Comprehensive ICU of Miyun Teaching Hospital (Miyun ICU) before antimicrobial treatment from 2017 to 2020. Microorganism cultures of the blood samples were conducted, and positive cultures were tested for type of pathogens and drug-susceptibility. 
Results: The prevalence of BSIs was the highest in the Miyun ICU (10.85%), followed by the RICU (9.48%) and the PICU (8.36%). The total prevalence of Gram-positive bacterial strains (especially Staphylococcus spp. and Enterococcus spp.) in the PICU, SICU, CICU, GICU and Miyun ICU was higher than Gram-negative bacteria. The major bacterial strain was Acinetobacter baumannii in the PICU (21.82%); Klebsiella pneumoniae in the SICU (12.88%), CICU (30.00%) and RICU (30.39%); Escherichia coli in GICU (20.75%); and Staphylococcus epidermidis (n=50, 18.18%) in Miyun ICU. Staphylococcus hominis of BSIs remained highly susceptible (>70%) to gentamicin, linezolid, daptomycin, teicoplanin, vancomycin, tigecycline and rifampicin in all the ICUs. Its antibiotic sensitivity to levofloxacin was moderate in the PICU and CICU, but mild (<30%) in the SICU, RICU and GICU. K. pneumoniae was highly susceptible to doxycycline, minocycline, tigecycline in all the ICUs except RICU, and its antibiotic sensitivity to imipenem, meropenem, amikacin, ciprofloxacin and levofloxacin was high/moderate in PICU, CICU, GICU and Miyun hospital ICU, but mild in the SICU and RICU.
Conclusions: The current study demonstrated the distribution of prevalent microorganisms and their antimicrobial susceptibility exhibited a high divergence among BSIs in different ICUs from a tertiary hospital and an outer suburban hospital. Therefore, different antibiotic therapies for various wards and distinct age groups should be considered to control the emergence and spread of highly antibiotic-resistant infections.