Investigation of In-vitro Efficacy of Intravenous Fosfomycin in Extensively Drug-Resistant Klebsiella pneumoniae Isolates and Effect of Glucose 6-Phosphate on Sensitivity Results

•Carbapenem-resistant Enterobacterales strains are a serious problem; treatment options for critically ill infected patients are limited•Studies evaluating the in vitro activity of fosfomycin against these strains are insufficient•The medium used in the susceptibility studies does not contain G6-P; therefore, the resistance results may be erroneously high•Sensitivity was 7% and 90.7% in sensitivity tests performed without and with addition of G6-P, respectively•These results show the potential of fosfomycin in the treatment of intensely resistant Klebsiella infections for which there are no effective drugs.