This study aims to describe trends of mcr-positive Enterobacterales in humans based on laboratory surveillance with a defined catchment population. The data source is the Micro-RER surveillance system, established in Emilia-Romagna region (Italy), to monitor the trend of mcr resistance. Enterobacterales isolates from human clinical samples with minimum inhibitory concentration (MIC) >= 2 mg/L for colistin were sent to the study reference laboratory for the detection of mcr genes. Isolates prospectively collected in the period 2018-2020 were considered for the assessment of population rates and trends; further analyses were carried out for the evaluation of clonality and horizontal mcr gene transfer. Previous isolates from local laboratory collection were also described. In the period 2018-2020, 1164 isolates were sent to the reference laboratory, and 51 (4.4%) were confirmed as mcr-positive: 50 mcr-1 (42 Escherichia coli, 6 Klebsiella pneumoniae, 2 Salmonella enterica) and 1 mcr-4 (Enterobacter cloacae). The number of mcr-positive isolates dropped from 24 in the first half of 2018 to 3 in the whole of 2020 (trend p value < 0.001). Genomic analyses showed the predominant role of the horizontal transfer of mcr genes through plasmids or dissemination of transposable elements compared to clonal dissemination of mcr-positive microorganisms. The study results demonstrate a substantial decrease in the circulation of mcr-1 plasmid genes in Emilia-Romagna Region.
Reduction trend of mcr-1 circulation in Emilia-Romagna Region, Italy / Gagliotti, C., Bolzoni, L., Carretto, E., Sarti, M., Ricchizzi, E., Ambretti, S., Barozzi, A., Bracchi, C., Confalonieri, M., Menozzi, I., Morganti, M., Pedna, M.F., Sambri, V., Scaltriti, E., Schiavo, R., Soliani, L., Tambassi, M., Venturelli, C., Biagetti, C., Buttazzi, R., et al.. - In: EUROPEAN JOURNAL OF CLINICAL MICROBIOLOGY & INFECTIOUS DISEASES. - ISSN 0934-9723. - 40:12(2021), pp. 2585-2592. [10.1007/s10096-021-04318-y]
Reduction trend of mcr-1 circulation in Emilia-Romagna Region, Italy
Gagliotti C.Methodology
;Carretto E.Membro del Collaboration Group
;Ricchizzi E.Methodology
;Ambretti S.Membro del Collaboration Group
;Barozzi A.Membro del Collaboration Group
;Bracchi C.Membro del Collaboration Group
;Scaltriti E.Membro del Collaboration Group
;Tambassi M.Membro del Collaboration Group
;Venturelli C.Membro del Collaboration Group
;Calderaro A.Membro del Collaboration Group
;Pongolini S.Membro del Collaboration Group
;
2021-01-01
Abstract
This study aims to describe trends of mcr-positive Enterobacterales in humans based on laboratory surveillance with a defined catchment population. The data source is the Micro-RER surveillance system, established in Emilia-Romagna region (Italy), to monitor the trend of mcr resistance. Enterobacterales isolates from human clinical samples with minimum inhibitory concentration (MIC) >= 2 mg/L for colistin were sent to the study reference laboratory for the detection of mcr genes. Isolates prospectively collected in the period 2018-2020 were considered for the assessment of population rates and trends; further analyses were carried out for the evaluation of clonality and horizontal mcr gene transfer. Previous isolates from local laboratory collection were also described. In the period 2018-2020, 1164 isolates were sent to the reference laboratory, and 51 (4.4%) were confirmed as mcr-positive: 50 mcr-1 (42 Escherichia coli, 6 Klebsiella pneumoniae, 2 Salmonella enterica) and 1 mcr-4 (Enterobacter cloacae). The number of mcr-positive isolates dropped from 24 in the first half of 2018 to 3 in the whole of 2020 (trend p value < 0.001). Genomic analyses showed the predominant role of the horizontal transfer of mcr genes through plasmids or dissemination of transposable elements compared to clonal dissemination of mcr-positive microorganisms. The study results demonstrate a substantial decrease in the circulation of mcr-1 plasmid genes in Emilia-Romagna Region.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
