Ballot et al. BMC Pediatrics (2019) 19:320 https://doi.org/10.1186/s12887-019-1709-y RESEARCH ARTICLE Open Access A review of -multidrug-resistant Enterobacteriaceae in a neonatal unit in Johannesburg, South Africa Daynia E. Ballot1,2* , Rosella Bandini3, Trusha Nana4, Noma Bosman4, Teena Thomas4, Victor A. Davies1, Peter A. Cooper1, Mervyn Mer2,5 and Jeffrey Lipman2,6 Abstract Background: Multi-drug resistant organisms are an increasingly important cause of neonatal sepsis. Aim: This study aimed to review neonatal sepsis caused by multi-drug resistant Enterobacteriaceae (MDRE) in neonates in Johannesburg, South Africa. Methods: This was a cross sectional retrospective review of MDRE in neonates admitted to a tertiary neonatal unit between 1 January 2013 and 31 December 2015. Results: There were 465 infections in 291 neonates. 68.6% were very low birth weight (< 1500 g). The median age of infection was 14.0 days. Risk factors for MDRE included prematurity (p = 0.01), lower birth weight (p = 0.04), maternal HIV infection (p = 0.02) and oxygen on day 28 (p < 0.001). The most common isolate was Klebsiella pneumoniae (66.2%). Total MDRE isolates increased from 0.39 per 1000 neonatal admissions in 2013 to 1.4 per 1000 neonatal admissions in 2015 (p < 0.001). There was an increase in carbapenem-resistant Enterobacteriaceae (CRE) from 2.6% in 2013 to 8.9% in 2015 (p = 0.06). Most of the CRE were New Delhi metallo—β lactamase- (NDM) producers. The all-cause mortality rate was 33.3%. Birth weight (p = 0.003), necrotising enterocolitis (p < 0.001) and mechanical ventilation (p = 0.007) were significantly associated with mortality. Serratia marcescens was isolated in 55.2% of neonates that died. Conclusions: There was a significant increase in MDRE in neonatal sepsis during the study period, with the emergence of CRE. This confirms the urgent need to intensify antimicrobial stewardship efforts and address infection control and prevention in neonatal units in LMICs. Overuse of broad- spectrum antibiotics should be prevented. Keywords: Neonatal Sepsis, Enterobacteriaceae, Carbapenem-resistant, Klebsiella pneumoniae Background due to MDRO [3]. In a recent report from Jordan, two Sepsis remains a major cause of morbidity and mortality thirds of organisms causing neonatal sepsis were MDRO in preterm infants [1]. There has been a significant in- and most of the gram-negative organisms were ex- crease in neonatal sepsis caused by multi-drug resistant tended-spectrum beta-lactamase (ESBL) producers [1]. organisms (MDRO) in the past decade [1, 2]. More than Many preterm infants are colonised with MDRO - more half the organisms causing bloodstream infections (BSI) than half the Klebsiella pneumoniae and Escherichia coli in a neonatal unit in Johannesburg, South Africa were isolated from a group of preterm infants in Malaysia were MDRO [4]. * Correspondence: [email protected] Infections with multi-drug resistant gram-negative 1 Neonatal Unit, Department of Paediatrics and Child Health, University of the organisms, especially Enterobacteriaceae, are of concern Witwatersrand and Charlotte Maxeke Johannesburg Academic Hospital, Johannesburg, South Africa in preterm infants. Neonatal sepsis caused by these 2Infection control, Charlotte Maxeke Johannesburg Academic Hospital, pathogens is increasing and there are limited choices Johannesburg 2196, South Africa available for treatment [5]. Infections with multi-drug Full list of author information is available at the end of the article © The Author(s). 2019 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Ballot et al. BMC Pediatrics (2019) 19:320 Page 2 of 9 resistant Enterobacteriaceae (MRDE) are associated with (bioMerieux, Marcy-I’Etoile, France) minimum inhibitory poor outcome and high case fatality rates, especially in concentration (MIC) testing. Colistin broth micro-dilution low and middle income countries (LMIC) [5]. Mecha- testing was not performed and hence colistin susceptibility nisms of antibiotic resistance in Enterobacteriaceae rates cannot be reported for all isolates. Multiplex PCR for include production of ESBLs or carbapenemases [5]. the carbapenemase genes (for blaNDM, blaKPC, There are recent reports of colistin-resistant Enterobac- blaOXA-48 and its variants, blaGES, blaIMP and blaVIM; teriaceae in neonates [4]. LightMix Modular kits, Roche Diagnostics, Basel, Carbapenem-resistant organisms were already de- Switzerland) was performed on a subset of the CRE scribed as a cause of neonatal septicaemia in India in isolates. Typing of isolates was not performed. 2007 [6]. It is not clear whether patterns of ESBL and carbapenem-resistant Enterobacteriaceae (CRE) reflect Statistical analysis national resistance patterns or are specific to the neonatal IBM SPSS 24 was used to analyse the data.. Maternal units. The predominant CRE strain in Asia and the West and neonatal characteristics were described for each pa- Pacific is New Delhi metallo-beta-lactamase (NDM − 1), tient (not bacterial isolate). Microbiological information whereas that in Europe and the USA is Klebsiella pneumo- (resistance patterns, isolates over time) was analysed for niae carbapenemase (KPC) [5]. There is limited informa- each bacterial isolate. Mean and standard deviation or tion on CRE in Africa. There is a report from Morocco median and range, were used to describe central where the predominant strain was OXA β-lactamase, i.e. tendency in continuous variables, depending on the OXA-48 carbapenemase [7]. distribution of the data. Categorical variables were {Magiorakos, 2012 #2052} NDM and KPC (KPC-2) described using frequency and percentages. Only valid were first described in adult patients in Johannesburg in cases were analysed for each variable (i.e. missing cases 2011 [8]. The aim of this study is to describe the were excluded). Two comparisons were performed. patterns of MDRE, including CRE, in a neonatal unit in Firstly, survivors and non- survivors within the MDRE Johannesburg, South Africa. group were compared to determine risk factors for mor- tality. Secondly, the MDRE group and control group Subjects and methods were compared to establish associations with MDRE in- This is a retrospective descriptive cross-sectional fection. Frequencies were compared using Chi Square study. All newborn neonates admitted to the neonatal analysis, while unpaired t tests were used to compare unit between 01 January 2013 and 31 December 2015 continuous variables, as the data was normally distributed. were eligible for inclusion. The study group included A p value of 0.05 was considered to be statistically all neonates with culture proven blood stream infec- significant. Adjusted odds ratios were determined through tion (BSI) caused by MDRE. A control group of 30% binary logistic regression for significant associations with of all neonates without infection admitted to the neo- mortality and MDRE infection respectively. natal unit during the study period was randomly gen- erated from the neonatal database using SPSS IBM Ethics 24. Subjects were identified through the laboratory in- Ethics clearance was obtained from the Human formation system of the National Health Laboratory Research Ethics Committee of the University of the Service (NHLS). Patient characteristics were obtained Witwatersrand (Certificate M 151108). Permission was from the neonatal computer database. Information obtained to access the Laboratory information system was obtained from hospital records on discharge of from the NHLS. each neonatal patient and was entered into a compu- teriseddatabaseforthepurposeofqualitycontrol. Definitions Data was managed using Research Electronic Data Early-onset sepsis (EOS) was defined as culture Capture (REDCAP), hosted by the University of the proven sepsis within the first 72 h of life, while late Witwatersrand [9]. Maternal information, demo- onset sepsis (LOS) was referred to as culture proven graphic and clinical characteristics, as well as survival sepsis after 72 h of life [1]. Multidrug resistance was to hospital discharge, were described for each patient. defined as the isolate being non-susceptible to ≥1 Causative organisms and their antimicrobial sensitivity agent in ≥3 antimicrobial categories [10]. The pres- patterns were described. Organism identification and ence of resistance to third generation cephalosporins antimicrobial susceptibility testing was done on the wasusedasamarkerforESBLproduction.The Vitek 2® (bioMerieux, Marcy-I’Etoile,France).Vitek2 presence of cefoxitin resistance was used as a marker breakpoint interpretation was based on the Clinical and for Amp C beta-lactamase production. Necrotising Laboratory Standards Institute (CLSI) guidelines. Isolates enterocolitis (NEC) was defined as modified Bell’s were characterised as CRE based on carbapenem Etest® stages 2 or 3 [11]. Resuscitation at birth was defined Ballot et al. BMC Pediatrics (2019) 19:320 Page 3 of 9 Table 1 Characteristics associated with multi-drug resistant Enterobacteriaceae infection in neonates