Carbapenem-resistant Enterobacterales among patients with bloodstream infections in South Africa: Consolidated surveillance data, 2015-2021.

backgroundA fifth of blood cultures from patients with infections acquired in a healthcare setting in South Africa will yield an organism. Carbapenem-resistant Enterobacterales (CREs), specifically Klebsiella pneumoniae are the most predominant Gram-negative bacteria (GNB) isolated among bloodstream infections (BSI). Additionally, the multidrug-resistant nature of these organisms is not only a threat to patients but it also poses a big public health challenge to current treatments and highlights the need for the development of new antimicrobials. Therefore, CRE have been placed on the critical priority list by the World Health Organization (WHO). We aimed to provide a holistic overview of the GERMS-SA CRE BSI surveillance data from 01 July 2015-31 December 2021.

methodsWe conducted a cross-sectional study. CRE BSI was defined as the isolation of Enterobacterales resistant to any carbapenem (imipenem, ertapenem, meropenem and doripenem). All culture-confirmed cases captured on the database from 01 July 2015-31 December 2021 were considered for descriptive analysis and all cases with additional clinical information from 01 July 2015-31 December 2020 collected through the case report form (CRF) were used to perform analytical inferential statistics. We calculated the case fatality ratio of all cases with the outcome reported.

resultsOf the 5,258 culture-confirmed cases in the database for the surveillance period, the median age was 31 years (interquartile range 11-50) and 53.0% (2,787/5,258) were males. The majority of cases (64.6%, 1,361/2,017) were from Gauteng province that are participating in GERMS-SA surveillance. Of the cultures that isolated organisms, 53.0% (2,699/5,258) were sent to a reference laboratory for further testing. Case report forms were collected from 2,935 cases and these included audit cases. The clinical outcome was recorded for 99.5% (2,919/2,935) of the cases with a case fatality ratio of 36.1% (1,055/2,919). About 44.5% (1,298/2,916) of the cases had pre-existing conditions, most of which were other (n = 601). Most cases (78.4%, 2,288/2,920) received antibiotics on the current admission and 85.4% (2,488/2,912) had devices inserted. Of the 2,699 viable isolates, 2,100 (78%) were confirmed to be resistant to any of the carbapenems and 93.0% (n = 1,951) were carbapenemase-producing CREs. The carbapenem-resistant rate of all BSI was 1.9% (5,258/270,239). Of the CRE isolates, most were highly susceptible to fosfomycin (80.4%, 1,688/2,100). The potential significant risk factors for CRE BSI related mortality from multivariable logistic regression were being male, over 60 years, with pre-existing conditions, previously on antibiotics, mechanical ventilation as well as oxygenation, and previous hospital admission.

conclusionPeriodic surveillance for CRE should be performed on regular basis to support infection prevention and stewardship program at each facility.