Abstract:
OBJECTIVE :
We aimed to provide an analysis of A. baumannii complex (ABC) isolated from blood cultures in South Africa.
MATERIALS AND METHODS :
ABC surveillance was conducted from 1 April 2017 to 30 September 2019 at 19 hospital
sites from blood cultures of any age and sex. Organism identification was performed using
the MALDI-TOF MS and antimicrobial susceptibility testing (AST), MicroScan Walkaway
System. We confirmed colistin resistance with Sensititre, FRCOL panel, and selected for
whole-genome sequencing.
RESULTS :
During the study period, we identified 4822 cases of ABC, of which 2152 cases were from
19 enhanced surveillance sites were reported during the enhanced surveillance period (1
August 2018 to 30 September 2019). Males accounted for 54% (2611/4822). Of the cases
with known age, 41% (1968/4822) were infants (< 1-year-old). Seventy-eight percent (1688/
2152) of cases had a known hospital outcome, of which 36% (602/1688) died. HIV status
was known for 69% (1168/1688) of cases, and 14% (238/1688) were positive. Eighty-two percent (1389/1688) received antimicrobial treatment in admission. Three percent (35/
1389) of cases received single colistin. Four percent (75/2033) were resistant to colistin. At
least 75% of the isolates (1530/2033) can be classified as extensively drug-resistant (XDR),
with resistance to most antibiotics except for colistin. The majority, 83% (20/24), of the colistin-resistant isolates were of the sequence type (ST) 1. Resistance genes, both plasmidand chromosomal- mediated were not observed. Although all isolates had, nine efflux pump
genes related to antimicrobial resistance.
CONCLUSION :
Our surveillance data contributed to a better understanding of the natural course of A. baumannii disease, the patient characteristics among infants, and the level of resistance. At
least two-thirds of the isolates were extensively drug-resistant, and four percent of isolates
were resistant to colistin.
