RESUMEN
In the context of increasing antimicrobial resistance in Enterobacterales, the management of these UTIs has become challenging. We retrospectively assess the prevalence of antimicrobial resistance in Enterobacterales isolates recovered from urinary tract samples in France, between 1 September 2017, to 31 August 2018. Twenty-six French clinical laboratories provided the susceptibility of 134,162 Enterobacterales isolates to 17 antimicrobials. The most frequent species were E. coli (72.0%), Klebsiella pneumoniae (9.7%), Proteus mirabilis (5.8%), and Enterobacter cloacae complex (2.9%). The overall rate of ESBL-producing Enterobacterales was 6.7%, and ranged from 1.0% in P. mirabilis to 19.5% in K. pneumoniae, and from 3.1% in outpatients to 13.6% in long-term care facilities. Overall, 4.1%, 9.3% and 10.5% of the isolates were resistant to cefoxitin, temocillin and pivmecillinam. Cotrimoxazole was the less active compound with 23.4% resistance. Conversely, 4.4%, 12.9%, and 14.3% of the strains were resistant to fosfomycin, nitrofurantoin, and ciprofloxacin. However, less than 1% of E. coli was resistant to fosfomycin and nitrofurantoin. We identified several trends in antibiotics resistances among Enterobacterales isolates recovered from the urinary tract samples in France. Carbapenem-sparing drugs, such as temocillin, mecillinam, fosfomycin, cefoxitin, and nitrofurantoin, remained highly active, including towards ESBL-E.
RESUMEN
Plasmids are the main vectors of antimicrobial drug resistance and virulence genes, especially in Enterobacteriaceae. Identification and classification of plasmids is essential for analysis of their distribution. The most widely used typing method is PCR-based replicon typing (PBRT). A new classification scheme based on relaxase gene typing has been described recently. We propose a practical application of this method, with the development of a multiplex PCR set targeting relaxase genes found on plasmids most frequently encountered in Enterobacteriaceae. This method, here called "plasmid relaxase gene typing" (PRaseT), was validated with 60 transconjugants and transformants harboring various replicon types. The method was tested with 39 multidrug-resistant clinical isolates including Escherichia coli, Klebsiella pneumoniae and Salmonella enterica subsp. enterica carrying 1-7 replicons as well as with 17 plasmids non-typeable using PBRT; all replicons were tested in parallel with PBRT for comparison. Six multiplex PCRs and one simplex PCR, including 24 pairs of primers, recognized plasmids of groups A/C, B/O, colE, FIA, FIB, FIC, FV, FIIk, HI1, HI2, I1, K, L/M, N, P1α, Q1, U, W, X1, X2, X3 and X4. There was perfect correlation between PRaseT and PBRT results in 31/39 (79.5%) clinical isolates. Moreover, 11/17 (64.7%) plasmids non-typeable by PBRT could be typed by PRaseT. Our set of multiplex PCRs showed high sensitivity and specificity for the classification of resistance plasmids. It has proved complementary to the widely used PBRT and will improve the monitoring of plasmid distribution in every-day practice.
