Detection of Carbapenemase Encoding Gene and Resistance to Cefiderocol in Hospital and Community eXtensive Drug Resistance and Carbapenem-Resistant Pseudomonas aeruginosa Strains in Morocco.

Pseudomonas aeruginosa (Pa) remains among clinically-significant Gram-negative species. The carbapenems are often the last resort for treating infections due to multidrug resistant isolates such as Pa. The carbapenems' efficacy is increasingly compromised by the emergence and the rapid spread of Pa carrying carbapenemases which represent a serious threat to public health. This study aimed to establish the resistance profile and to identify carbapenemase genes in isolates with imipenem resistant phenotypes. Among 134 Pa isolates collected both in the community (46) and hospital (88) from January 2021 to December 2021 in Morocco, 18 (8 were from the community and 10 from the hospital settings) were carbapenem resistant. The identification of these strains has been confirmed using matrix assisted laser desorption ionization-time of flight (MALDI-TOF). The antibiotic susceptibility testing against 16 antibiotics was carried out and interpreted according to the recommendations of the European Committee on Antimicrobial Susceptibility Testing (2021). The worrying antibiotics resistance profiles, which spread to cefiderocol for two isolates, were obtained for all isolates, which were eXtensive Drug Resistance showing highly resistant to all antibiotic categories tested, even to ceftolozane-tazobactam. Colistin (100% susceptible) and cefiderocol (88.88%) were the most active agents against carbapenem-resistant Pa (CRPa). Phenotypic detection by NP-CARBA and NG-CARBA tests of metallo­ß­lactamase (MßL) production was confirmed by PCR amplification and sequencing. Three CRPa isolates coharboring blaVIM-2-blaNDM-1 (two isolates) and blaVIM-2-blaIMP-8 (one isolate) genes were detected. In this study, we describe the coexistence of these MßL genes and the cefiderocol resistance in CRPa strains in Morocco. The alarming antibiotic resistance patterns of all these CRPa isolates and their resistance genes emphasize the importance of antimicrobial susceptibility testing in the choice of antibiotics for treating Pa infections.

Detection of ESBLs and carbapenemases among Enterobacteriaceae isolated from diabetic foot infections in Ouargla, Algeria.

INTRODUCTION: The emergence and rapid spread of Enterobacteriaceae carrying extended spectrum beta-lactamases (ESBLs) and carbapenemases represent a great threat to clinical treatment due to their multi-drug resistance. This study investigated ESBLs and carbapenemases encoding genes in Enterobacteriaceae collected from diabetic foot infections (DFIs) in Ouargla, southern Algeria. METHODOLOGY: A total of 70 Enterobacteriaceae strains were recovered from 76 patients with DFI between February 2017 and April 2018. Antimicrobial susceptibility testing was performed using the disc diffusion method, and the presence of bla genes was detected using polymerase chain reaction (PCR) and DNA sequencing. The genetic transfer of the plasmids was carried out by conjugation using the broth mating method. RESULTS: The most common isolate was Proteus mirabilis, followed by Escherichia coli, Morganella morganii and Klebsiella pneumoniae. The prevalence of ESBL and carbapenemase-producing Enterobacteriaceae was 11.42% and 2.85 % respectively. Plasmid-mediated AmpC was detected in 5.71% isolates. Conjugation experiments showed the transferability of blaCTX-M-2. CONCLUSIONS: Our findings support the view that various pathogens found in DFIs differ from one part of the country to another. This study reports the first description of metallo-ß-lactamase NDM-5 producing Klebsiella pneumoniae clinical isolate in Algeria.

Emergence of extended-spectrum beta-lactamases-producing Escherichia coli in community-acquired urinary infections in Casablanca, Morocco.

INTRODUCTION: Extended-spectrum beta-lactamase- (ESBL)-producing Escherichia coli are an increasingly significant cause of community-acquired infection worldwide. The aim of this study was to assess the prevalence of ESBL-producing E. coli in a community, to analyze the relationship between strains studied, and to characterize the ESBL genes involved in this resistance. METHODOLOGY: ESBL production was detected by the double disk synergy test. Genes encoding ESBLs (blaTEM, blaCTM, blaSHV) were identified by PCR and DNA sequencing. Conjugation experiments were performed to check the transferability of antibiotic resistance genes. Strain inter-relationships were studied by pulsed field gel electrophoresis. RESULTS: Seven ESBL-producing E. coli were identified among the 535 E. coli isolates. Most of them expressed a CTX-M enzyme (6/7) with a predominance of CTX-M-15 (6/6). Two strains possessed TEM in combination with CTX-M-15 or SHV-5.  Plasmid content and gene transfer analysis showed that resistance genes were carried by high molecular weight conjugative plasmids. PFGE analysis showed that the strains were not clonal. CONCLUSIONS: ESBL-producing E. coli from urinary tract infections in Casablanca belong to different clones and carry mobile beta-lactamase genes.  It is therefore essential to monitor the epidemiology of ESBLs in E. coli and related organisms locally to effectively combat resistance.

Characterization of extended-spectrum ß-lactamase-producing Escherichia coli and Klebsiella pneumoniae isolates from the community in Morocco.

Of 803 community Escherichia coli (n = 767) and Klebsiella pneumoniae (n = 36) isolates collected from patients with urinary tract infections in three Moroccan cities, 10 E. coli (1.3%) and 2 K. pneumoniae (5.6 %) isolates were shown to produce extended-spectrum ß-lactamases (ESBLs). PFGE revealed that the E. coli isolates comprised seven distinct genotypes. The presence of plasmids in the 12 isolates was revealed by conjugation experiments of plasmids from these Enterobacteriaceae strains with E. coli K(12)J(5), with further isolation of the plasmids in the transconjugants. Subsequent nucleotide sequencing indicated that the plasmids encoded the bla(CTX-M), bla(OXA), bla(TEM) and bla(SHV) genes, including genes for CTX-M-15 (n = 11), OXA-1 (n = 11), TEM-1b (n = 4), SHV-5 (n = 1) and SHV-1 (n = 2). Identification of plasmid-mediated quinolone-resistance genes was performed by PCR. The aac(6')Ib-cr variant was detected in all strains, and two strains co-expressed qnrS1, bla(CTX-M-15) and bla(OXA-1) genes. The presence of ESBLs in the Enterobacteriaceae strains studied was probably due to the dissemination of resistance plasmids with the predominant genotype of bla(CTX-M-15.).