TABLE 1

Limit of detection of colistin-resistant Enterobacteriaceae on ChromID Colistin R and Superpolymyxin media

Colistin susceptibility and speciesStrain nameColistin MIC
(mg/liter)
Colistin resistanceLowest LOD (CFU/ml) ina:Reference or
source
Plasmid or
chromosome
encodedb
MechanismESwab Amies bufferSpiked stools
ChromID
Colistin R
SuperpolymyxinChromID
Colistin R
Superpolymyxin
Colistin-resistant Enterobacteriaceae (n = 53)
 Escherichia coliCNR 111 J716ChrPmrB mutations (D14N, S71C, V83A)1 × 1021 × 1041 × 1041 × 10621
CNR 201600394ChrUnknown1 × 102 >1 × 106 1 × 104 >1 × 108 21
CNR 201602358ChrMgrB mutation (V8A)1 × 105>1 × 106 1 × 107 >1 × 108 21
CNR 17288ChrPmrB mutation (G160E)1 × 106 1 × 1041 × 108 1 × 10621
414894Pmcr-11 × 1031 × 1051 × 1051 × 10721
J53 + mcr-1f8Pmcr-11 × 106 1 × 1041 × 108 1 × 10621
CNR201403854Pmcr-1>1 × 106 1 × 104 >1 × 108 1 × 10621
S08-0564Pmcr-11 × 1041 × 1031 × 1061 × 10521
CNR 117 G74Pmcr-1>1 × 106 1 × 104 >1 × 108 1 × 10622
CNR 121 G94Pmcr-11 × 106 1 × 1051 × 108 1 × 10723
R12 F54Pmcr-21 × 103 >1 × 106 1 × 105 >1 × 108 11
CNR 17454Pmcr-1>1 × 106 1 × 104 >1 × 108 1 × 10621
CNR 16044Pmcr-11 × 106 1 × 1041 × 108 1 × 10621
CNR 17904Pmcr-11 × 1031 × 1031 × 1051 × 10521
CNR 18594Pmcr-11 × 1031 × 1031 × 1051 × 10521
CNR 18864Pmcr-11 × 1021 × 1041 × 1041 × 10621
TOP10 + mcr-5f8Pmcr-51 × 1031 × 1051 × 1051 × 10721
42224Pmcr-11 × 1021 × 1031 × 1041 × 10521
40704Pmcr-11 × 1041 × 1031 × 1061 × 10521
9794Pmcr-11 × 1031 × 1031 × 1051 × 10521
63834Pmcr-1.51 × 1031 × 1041 × 1051 × 10621
17244Pmcr-11 × 1041 × 1031 × 1061 × 10521
16704Pmcr-1.51 × 1051 × 1051 × 1071 × 10721
360708Pmcr-3.21 × 1051 × 1051 × 1071 × 10724
CNR 164 A54Pmcr-11 × 105c >1 × 106 1 × 107>1 × 108 This study
 Klebsiella pneumoniaeCNR 2014004216ChrMgrB N42Y and K43I1 × 1031 × 1031 × 1051 × 105This study
CNR 2014066164ChrMgrB Q30 stop1 × 1021 × 1041 × 1041 × 106This study
CNR 2015111964ChrMgrB L4 stop1 × 1021 × 1041 × 1041 × 106This study
CNR 2015062264ChrMgrB Y41 stop1 × 1021 × 1031 × 1041 × 105This study
CNR 20150777128ChrMgrB Y41 stop1 × 1031 × 1041 × 1051 × 106This study
CNR 2015094464ChrMgrB modified sequence starting at aad 421 × 1021 × 1031 × 1041 × 105This study
CNR 2015030964ChrMgrB modified sequence starting at aa 371 × 1021 × 1041 × 1041 × 106This study
CNR 2015067564ChrmgrB truncated in ORFe by IS101 × 1021 × 1041 × 1041 × 106This study
CNR 2014048332ChrmgrB truncated in ORF by IS1F-like1 × 1031 × 1041 × 1051 × 106This study
CNR 2014056364ChrmgrB truncated in ORF by IS1R1 × 1021 × 1031 × 1041 × 105This study
CNR 2015005032ChrmgrB truncated in promoter by IS1R1 × 1031 × 1031 × 1051 × 105This study
CNR 2014059164ChrmgrB truncated in ORF by IS5-like1 × 1021 × 1041 × 1041 × 106This study
CNR 2014055032ChrmgrB truncated in promoter by IS903D1 × 1031 × 1041 × 1051 × 106This study
CNR 2015128532ChrmgrB truncated in ORF by IS903-like1 × 1031 × 1041 × 1051 × 106This study
S14-00264ChrmgrB truncated in promoter by ISKpn141 × 1021 × 1041 × 1041 × 106This study
CNR 2014010132ChrΔmgrB1 × 1031 × 1041 × 1051 × 106This study
CNR 201500732ChrΔmgrB1 × 1031 × 1041 × 1051 × 106This study
CNR 2015006616ChrΔmgrB1 × 103>1 × 106 1 × 105>1 × 108 This study
CNR 2015122332ChrΔmgrB1 × 1021 × 1031 × 1041 × 105This study
S1564ChrmgrB truncated in ORF by ISKpn251 × 1021 × 1041 × 1041 × 10625
CNR 163064/32ChrmgrB truncated in ORF by IS51 × 1021 × 1051 × 1041 × 107This study
CNR 186116ChrPmrB mutation (T157P)1 × 1031 × 1041 × 1051 × 106This study
CNR 160132Chr + Pmcr-1 + mgrB truncated in ORF by IS51 × 1021 × 1041 × 1041 × 106This study
CNR 17324Pmcr-11 × 1031 × 1031 × 1051 × 105This study
CNR 18534Pmcr-11 × 1031 × 1031 × 1051 × 105This study
 Salmonella enterica
        Serovar Paratyphi B d-tartrate + S. enterica biotype java2016106868Pmcr-11 × 1031 × 1051 × 1051 × 107This study
        Serovar TyphimuriumCNR 17768Pmcr-11 × 103>1 × 106 1 × 105>1 × 108 This study
        Serovar Paratyphi B d-tartrate + S. enterica biotype java13-SA017188Pmcr-51 × 103>1 × 106 1 × 105>1 × 108 8
Colistin-susceptible Enterobacteriaceae (n = 41)
 Escherichia coliTOP100.25>1 × 106 >1 × 106 >1 × 108 >1 × 108 21
16080718810.25>1 × 106 >1 × 106 >1 × 108 >1 × 108 21
16080722640.25>1 × 106 >1 × 106 >1 × 108 >1 × 108 21
16080737330.5>1 × 106 >1 × 106 >1 × 108 >1 × 108 21
16080732280.25>1 × 106 >1 × 106 >1 × 108 >1 × 108 21
16080786350.25>1 × 106 >1 × 106 >1 × 108 >1 × 108 21
16080788580.25>1 × 106 >1 × 106 >1 × 108 >1 × 108 21
16080626710.25>1 × 106 >1 × 106 >1 × 108 >1 × 108 21
16080648190.25>1 × 106 >1 × 106 >1 × 108 >1 × 108 21
2H60.25>1 × 106 >1 × 106 >1 × 108 >1 × 108 21
LAN 10.480.25>1 × 106 >1 × 106 >1 × 108 >1 × 108 21
VER 9.390.25>1 × 106 >1 × 106 >1 × 108 >1 × 108 21
1F10.25>1 × 106 1 × 106 >1 × 108 1 × 108 21
1A60.25>1 × 106 >1 × 106 >1 × 108 >1 × 108 21
1A80.25>1 × 106 >1 × 106 >1 × 108 >1 × 108 21
2A10.25>1 × 106 >1 × 106 >1 × 108 >1 × 108 21
2D90.5>1 × 106 >1 × 106 >1 × 108 >1 × 108 21
2C40.25>1 × 106 >1 × 106 >1 × 108 >1 × 108 21
2D50.25>1 × 106 >1 × 106 >1 × 108 >1 × 108 21
 K. pneumoniae16090564130.5>1 × 106 >1 × 106 >1 × 108 >1 × 108 This study
16090611491>1 × 106 >1 × 106 >1 × 108 >1 × 108 This study
2 E80.5>1 × 106 >1 × 106 >1 × 108 >1 × 108 This study
2 I40.5>1 × 106 >1 × 106 >1 × 108 >1 × 108 This study
2 F10.5>1 × 106 >1 × 106 >1 × 108 >1 × 108 This study
2 I50.5>1 × 106 >1 × 106 >1 × 108 >1 × 108 This study
3 B40.5>1 × 106 >1 × 106 >1 × 108 >1 × 108 This study
3 B70.5>1 × 106 >1 × 106 >1 × 108 >1 × 108 This study
1 B60.5>1 × 106 >1 × 106 >1 × 108 >1 × 108 This study
CNR 173 F90.5>1 × 106 >1 × 106 >1 × 108 >1 × 108 This study
1 C90.5>1 × 106 >1 × 106 >1 × 108 >1 × 108 This study
1 E31>1 × 106 1 × 104>1 × 108 1 × 106This study
2 B11>1 × 106 >1 × 106 >1 × 108 >1 × 108 This study
CNR 173 E30.5>1 × 106 >1 × 106 >1 × 108 >1 × 108 This study
2 C60.5>1 × 106 >1 × 106 >1 × 108 >1 × 108 This study
2 D20.5>1 × 106 >1 × 106 >1 × 108 >1 × 108 This study
 Salmonella enterica
        4,12:i:−2016047391>1 × 106 >1 × 106 >1 × 108 >1 × 108 This study
        Serovar Enteritidis2016089191>1 × 106 >1 × 106 >1 × 108 >1 × 108 This study
        Serovar Typhimurium2016065091>1 × 106 >1 × 106 >1 × 108 >1 × 108 This study
        Serovar Enteritidis2016075590.5>1 × 106 >1 × 106 >1 × 108 >1 × 108 This study
        Serovar Veneziana2016102990.5>1 × 106 >1 × 106 >1 × 108 >1 × 108 This study
 Enterobacter cloacaeCNR 131 G40.5Pmcr-4.2>1 × 106 >1 × 106 >1 × 108 >1 × 108 This study
  • a Underlined CFU counts are considered negative results. The sensitivity was 86.8% (95% CI = 74.0% to 94.0%) for both media after 48 h of incubation. The specificity was 100% (95% CI = 89.3% to 100%) and 97.5 (95% CI = 85.6% to 99.9%), respectively, for ChromID Colistin R and Superpolymyxin.

  • b P, plasmid; Chr, chromosome.

  • c After 48 h of incubation (no colony at 24 h).

  • d aa, amino acid.

  • e ORF, open reading frame.

  • f E. coli J53 was a recombinant strain harboring the mcr-1 gene on plasmid pDM1 (41522) (21). E. coli TOP10 was a recombinant strain harboring the mcr-5 gene on plasmid pSE13-SA01718 (21).