Distribution and antimicrobial resistance of gramnegative bacilli isolated from wound specimens of orthopedic patients

Abstract:

ObjectiveTo investigate the distribution and antimicrobial resistance of gramnegative bacilli isolated from wound specimens of orthopedic patients, and provide reference for the rational use of antimicrobial agents. Methods682 isolates of gramnegative bacilli were collected from orthopedic department in a comprehensive hospital between January 2011 and December 2013, antimicrobial susceptibility testing results were analyzed. ResultsThe main gramnegative bacilli isolated from wound specimens of orthopedic patients were Pseudomonas aeruginosa (P.aeruginosa) (16.72%), Escherichia coli (E.coli)(15.40%), and Enterobacter cloacae (E. cloacae)(12.76%). The detection rates of extendedspectrum betalactamase  producing E. coli and Klebsialla pneumoniae (K.pneumoniae) were 54.29%（57/105) and 31.43% （22/70） respectively, and mainly distributed in the trauma orthopedic department, accounting for 49.12% and 45.45% respectively.The susceptibility rates of E. coli, K. pneumoniae,and E. cloacae to meropenem and imipenem were all 100.00%. The susceptibility rates of E. coli and K. pneumoniae to amikacin, piperacillintazobactam and amoxicillin/clavulanic acid were all >80%. Susceptibility rate of E. cloacae to most antimicrobial agents were 71.26%-100.00% except for piperacillin(64.37%). Susceptibility rates of P. aeruginosa to most antimicrobial agents were >85% except for cefepime (78.95%) and aztreonam (65.79%).ConclusionGramnegative bacilli are the most common pathogens in wound infection of orthopedics patients. In order to use antimicrobial agents rationally and improve clinical treatment effect, it is important to realize the distribution of pathogens and antimicrobial resistance.