Treatment of hospital acquired urinary tract infections (UTIs) caused by extended-spectrum beta
-Lactamases producing
Klebsiella pneumonae is a major problem. This organism expresses a high level of resistance to many groups of antibiotics.
Fosfomycin is an agent which is recommended for treatment of UTIs caused by ESBLs producers. The aim of this study is to determine the sensitivity pattern of ESBLs producing urinary
K. pneumonae to antimicrobial agents including
fosfomycin in patients of MUHs and determine the prevalence of
fosfomycin resistance mediated by plasmid mediated
fosfomycin modifying enzymes
fosA,
fosB and
fosA3. Methods:
Klebsiella pneumonae urinary isolates were collected from patients with hospital acquired UTIs in Mansoura University Hospitals (MUHs). The susceptibility pattern was determined by Kirby Baur method. Isolates resistant to extended spectrum cephalosporins were tested for ESBLs production by double disc diffusion method.
Fosfomycin resistance was determined by broth dilution method. Isolates resistant to
fosfomycin were tested for
fosA,
fosB and
fosA3 by PCR. Results: A total of 128 ESBLs producing
K. pneumonae isolates were collected. The highest sensitivity was to imipenem (94.5%). The lowest was to trimethoprime-sulphamethoxazole (21.8%). Co-resistance of ESBLs isolates with
fosfomycin was 23.2%. Eighteen
fosfomycin resistant isolates (18/30) were positive to
fosA. Conclusion: ESBLs producing urinary
Klebsiella pneumonae express moderate sensitivity to
fosfomycin. Resistance is mainly mediated by plasmid mediated
fosfomycin modifying enzymes
fosA.