A comparison between conventional and stratified antibiograms for antibiotic empirical therapy among the most bacterial pathogens

Abstract

Antibiogramsprovideimportant data regarding antimicrobial selection duringempirical therapy and formonitoringyearly trends in antimicrobial resistance in healthcare settings. Antibiograms tailored to hospital location or specimen type are called stratified antibiograms. This retrospective study comparedconventional and stratified antibiograms for Escherichiacoli, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii,and Pseudomonas aeruginosaat the Hua-Hin hospital between January 2015 and December 2015. Stratifiedantibiograms were specific to the specimentypeor ward wereconstructed after eliminating duplicate samples. Susceptibilitiesof2,323 bacterial isolates of E. coli, S. aureus, K. pneumoniae, A. baumannii, and P. aeruginosa(32.6%, 15.6%, 15.4%, 16.0%,and 20.4%, respectively)wereanalyzed and percentage antimicrobial susceptibility did not differbetween the stratified antibiogram forthe first specimen alone and theconventional antibiogram. Similarly, percentage susceptibility between intensive care unit (ICU)and non-ICU wardsor specimen type wascomparablebetween the antibiograms. However, percentage susceptibilitiesof urinary P. aeruginosaisolates to amikacin, gentamicin,and ciprofloxacin were60.6, 59.2,and 57.7, respectively, whichwas lower than that seen in the conventional antibiogram,namely,84.1%(amikacin), 83.5%(gentamicin),and 80.1%(ciprofloxacin). Thus, stratified antibiograms,categorized by specimentypeor ward,may be more useful in selectingappropriate empirical therapy