Change in pathogens and antimicrobial resistance in neonatal septicemia during 6 years

Abstract:

ObjectiveTo understand the pathogens causing neonatal septicemia, as well as changing trend of antimicrobial resistance, and provide evidence for clinical antiinfection treatment. MethodsResults of blood culture and antimicrobial susceptibility testing of pathogens from neonates with septicemia  who were admitted to the department of neonatology of a hospital from January 2009 to December 2014 were analyzed retrospectively, distribution of pathogens and antimicrobial resistance between 2009-2011 and 2012-2014 were compared. ResultsA total of 259 strains were isolated from blood specimens, grampositive bacteria, gramnegative bacteria, and fungi were 175(67.57%), 65(25.10%), and 19（7.33%）respectively. Coagulasenegative staphylococcus (CNS) was the main pathogen during 6 years, followed by Klebsiella pneumoniae(K. pneumoniae); the constituent ratio of the extendedspectrum βlactamase (ESBLs)producing strains increased from 10.56% to 15.38%, constituent ratio of fungi increased from 4.93% to 10.25%（P＞0.05）; The sensitivity of grampositive bacteria to vancomycin, teicoplanin, and linezolid were all 100.00%, 82.28%-88.33% of CNS and 75.00%-100.00% of Staphylococcus aureus were methicillinresistant; the resistance rates of K. pneumoniae and Escherichia coli to the thirdgeneration cephalosporins  were 42.86%-86.67%，to cefoperazone/sulbactam increased from 17.39% and 14.29% to 33.33% and 30.00% respectively, meropenem and imipenemresistant strains were not found. Resistance rate of Candida albican to fluconazole increased from 20.00% to 50.00%，all detected fungi remained sensitive to amphotericin B. ConclusionCNS are the major pathogens in neonatal septicemia, followed by K. pneumoniae, constituent ratio of fungal infection has increased. Antimicrobial agents should be chosen according to blood culture and antimicrobial susceptibility testing results.