Mcr colistin resistance gene: a systematic review of current diagnostics and detection methods

Abstract

Resistance to colistin, mediated by chromosomal mutations and more recently, by plasmid-borne mcr genes, is increasingly being reported in bacterial isolates taken from humans, animals, farms, foods, and the environment. To easily identify and contain this quickly spreading menace, efficient diagnostics that are cheaper, faster, simpler, sensitive, and specific have become indispensable and urgently necessary. A thorough and systematic review of the literature available at Pubmed, ScienceDirect and Web of Science was thus undertaken to identify articles describing novel and efficient colistin resistance- and mcr gene-detecting methods. From the final 23 studies included in this review, both phenotypic and molecular tests were found. The phenotypic tests consisted of novel culture media viz., SuperPolymyxin™, CHROMagar COL-APSE and LBJMR media, commercial automated MIC-determining instruments such as MICRONAUT-S, Vitek 2, BD Phoenix, Sensititre and MicroScan, and novel assays such as Colistin MAC test, Colispot, rapid polymxin NP test (RPNP), alteration of Zeta potential, modified RPNP test, MICRONAUT-MIC Strip, MIC Test Strip, UMIC System, and Sensitest™ Colistin. Molecular diagnostics consisted of the CT103XL microarray, eazyplex SuperBug kit, and Taqman /SYBR Green real-time PCR assays, with 100% sensitivity and specificity plus a shorter turnaround time (<3 hr). Based on the sensitivity, specificity, cost, required skill and turnaround time, the RPNP test and/or novel culture media is recommended for under-resourced laboratories while the Multiplex PCR or Taqman /SYBR Green real-time PCR assay alongside the RPNP or novel culture media is suggested for well-resourced ones.

New approach to identify colistin‐resistant Pseudomonas aeruginosa by high‐resolution melting curve analysis assay

“…PCR amplification was done in 50 µ l reaction volumes containing 0·5 µ mol l −1 of each primer (presented in Table ), 25 µ mol l −1 2X master mix (Ampliqon Inc., Odense, Denmark) 1 µ l (1000 ng) of pDNA and gDNA extract, and 23 µ l of supplied deionized water. Amplification was done using PCR thermocycler 1001C (Bio‐Rad, Hercules, CA) using the following profile: initial denaturation at 95°C for 5 min, 35 cycles of denaturation at 95°C for 1 min, annealing at 61°C for 1 min, and extension at 72°C for 1 min, and a final extension at 72°C for 5 min(Won et al ; Lee and Ko ; Osei Sekyere ) The PCR products (10 μl) were analysed by electrophoresis on 1% agarose gel. In this study, we performed the Sangar chain termination method for the 16srRNA, mcr‐1 and the PmrA sequencing.…”

“…Colistin‐resistant Pseudomonas aeruginosa (CRPA) strains have been detected in many infections, including wound and bloodstream. (Lee and Ko ; El Sayed Zaki et al ; Osei Sekyere ). Resistance to polymyxins most frequently results from the modification of the LPS caused by the addition of a 4‐amino‐4‐deoxy‐l‐arabinose moiety in the lipid A structure and the underlying mutations are frequently tracked to the PmrAB or PhoPQ two‐component regulators, which in turn lead to the activation of the pmrACADTEF operon (Osei Sekyere et al ; Chalmers et al ).…”

“…Resistance to polymyxins most frequently results from the modification of the LPS caused by the addition of a 4‐amino‐4‐deoxy‐l‐arabinose moiety in the lipid A structure and the underlying mutations are frequently tracked to the PmrAB or PhoPQ two‐component regulators, which in turn lead to the activation of the pmrACADTEF operon (Osei Sekyere et al ; Chalmers et al ). Also, mobile colistin resistance 1( mcr‐1 ), a colistin resistance‐encoding gene, has spread globally in recent years(Osei Sekyere ) The mcr‐1 gene is particularly important in CRPA strains due to it carrying on the plasmid DNA (pDNA) and its genetic transmission to other bacteria (Chabou et al ). Is highly effective against multidrug‐resistant (MDR) Gram‐negative pathogens such as P. aeruginosa (Jean et al .…”

Genomic analysis of a multidrug‐resistant clinical Providencia rettgeri (PR002) strain with the novel integron ln1483 and an A/C plasmid replicon

“…The MASTDISCS Combi tests (Mast Group, Johannesburg, South Africa) were used to phenotypically confirm ESBL and AmpC phenotype. The susceptibility breakpoints were interpreted using the CLSI version 7.1 (CLSI, 2018) and EUCAST (for Colistin and tigecycline) breakpoints …”

“…The susceptibility breakpoints were interpreted using the CLSI version 7.1 (CLSI, 2018) and EUCAST (for Colistin and tigecycline) breakpoints. [13][14][15] Genomic sequencing assembly and gene annotation The whole genome sequencing was performed on the Ion Proton instrument (Thermo Fisher Scientific, Waltham, MA), with a 97× coverage.…”