IJAA Editor's Choice

The following article has been selected as 'Editor's Choice' for the December issue of IJAA:

Prevalence and Mechanisms of Fosfomycin Resistance among KPC-Producing Klebsiella pneumoniae Clinical Isolates in China (Huang et al)

Editor's Comment:

Following the increase in resistance to beta-lactam antibiotics, especially carbapenems, clinicians became interested in an old antibiotic, fosfomycin. This antibiotic has the advantage of having a unique antibacterial mechanism of action, assuming that it can be active in multidrug-resistant bacteria. However, resistance mechanisms have already been identified, notably by modification of the target, impermeability, but above all acquisition of a plasmid-mediated fosA gene hydrolyzing fosfomycin. In China, this antibiotic has been reused for several years now, but the prevalence and mechanisms of fosfomycin resistance are poorly known. The authors of this work investigated the mechanism of fosfomycin resistance in 80 carbapenemase KPC-producing Klebsiella pneumoniae isolates, highlighted a rate of 80% of fosfomycin resistance. They showed that the fosA3 gene of plasmid origin was present in 36.3% of the strains and conferred a high level of resistance to fosfomycin. All KPC-KP also carried mutations or deletions in the fosfomycin target genes, notably in the glpt gene, suggesting that this mechanism is also common. Further investigations are needed to understand the role of this fos hydrolase, which is present in the genome of various bacterial genera.