TY - JOUR
T1 - Clonal expansion of colistin-resistant Acinetobacter baumannii isolates in Cape Town, South Africa
AU - Snyman, Yolandi
AU - Whitelaw, Andrew Christopher
AU - Reuter, Sandra
AU - Dramowski, Angela
AU - Maloba, Motlatji Reratilwe Bonnie
AU - Newton-Foot, Mae
N1 - Funding Information:
This study was supported by the NHLS Research Trust (grant number 94610) and Stellenbosch University Library's Open Access Publication Fund (grant number FFB007P). Personal funding was obtained by the NRF Innovation Masters Scholarship (grant number SFH160627174441). The funders had no role in the study design, data collection, analysis and interpretation of the data, decision to submit the work for publication, or preparation of the manuscript.
Funding Information:
This study was supported by the NHLS Research Trust (grant number 94610 ) and Stellenbosch University Library’s Open Access Publication Fund (grant number FFB007P). Personal funding was obtained by the NRF Innovation Masters Scholarship (grant number SFH160627174441 ). The funders had no role in the study design, data collection, analysis and interpretation of the data, decision to submit the work for publication, or preparation of the manuscript.
Publisher Copyright:
© 2019 The Author(s)
PY - 2020/2
Y1 - 2020/2
N2 - Objectives: To describe colistin-resistant Acinetobacter baumannii isolates in Cape Town, South Africa. Methods: A. baumannii isolates identified on Vitek 2 Advanced Expert System were collected from Tygerberg Hospital referral laboratory between 2016 and 2017. Colistin resistance was confirmed using broth microdilution and SensiTest. mcr-1–5 were detected using PCR and strain typing was performed by rep-PCR. Whole genome sequencing (WGS) was performed on a subset of isolates to identify chromosomal colistin resistance mechanisms and strain diversity using multilocus sequence typing (MLST) and pairwise single nucleotide polymorphism analyses. Results: Twenty-six colistin-resistant and six colistin-susceptible A. baumannii were collected separately based on Vitek susceptibility; 20/26 (77%) were confirmed colistin-resistant by broth microdilution. Four colistin-resistant isolates were isolated in 2016 and 16 in 2017, from five healthcare facilities. Thirteen colistin-resistant isolates and eight colistin-susceptible isolates were identical by rep-PCR and MLST (ST1), all from patients admitted to a tertiary hospital during 2017. The remaining colistin-resistant isolates were unrelated. Conclusions: An increase in colistin-resistant A. baumannii isolates from a tertiary hospital in 2017 appears to be clonal expansion of an emerging colistin-resistant strain. This strain was not detected in 2016 or from other hospitals. Identical colistin-susceptible isolates were also isolated, suggesting relatively recent acquisition of colistin resistance.
AB - Objectives: To describe colistin-resistant Acinetobacter baumannii isolates in Cape Town, South Africa. Methods: A. baumannii isolates identified on Vitek 2 Advanced Expert System were collected from Tygerberg Hospital referral laboratory between 2016 and 2017. Colistin resistance was confirmed using broth microdilution and SensiTest. mcr-1–5 were detected using PCR and strain typing was performed by rep-PCR. Whole genome sequencing (WGS) was performed on a subset of isolates to identify chromosomal colistin resistance mechanisms and strain diversity using multilocus sequence typing (MLST) and pairwise single nucleotide polymorphism analyses. Results: Twenty-six colistin-resistant and six colistin-susceptible A. baumannii were collected separately based on Vitek susceptibility; 20/26 (77%) were confirmed colistin-resistant by broth microdilution. Four colistin-resistant isolates were isolated in 2016 and 16 in 2017, from five healthcare facilities. Thirteen colistin-resistant isolates and eight colistin-susceptible isolates were identical by rep-PCR and MLST (ST1), all from patients admitted to a tertiary hospital during 2017. The remaining colistin-resistant isolates were unrelated. Conclusions: An increase in colistin-resistant A. baumannii isolates from a tertiary hospital in 2017 appears to be clonal expansion of an emerging colistin-resistant strain. This strain was not detected in 2016 or from other hospitals. Identical colistin-susceptible isolates were also isolated, suggesting relatively recent acquisition of colistin resistance.
KW - Acinetobacter baumannii
KW - Clonal expansion
KW - Colistin resistance
KW - South Africa
UR - http://www.scopus.com/inward/record.url?scp=85076418785&partnerID=8YFLogxK
U2 - 10.1016/j.ijid.2019.11.021
DO - 10.1016/j.ijid.2019.11.021
M3 - Article
C2 - 31765820
AN - SCOPUS:85076418785
SN - 1201-9712
VL - 91
SP - 94
EP - 100
JO - International Journal of Infectious Diseases
JF - International Journal of Infectious Diseases
ER -