Molecular epidemiology of Enterococcus sp. isolated in a university hospital in Algeria.

BACKGROUND: The aim of this study was to describe the epidemiology of enterococci isolated from infections at an Algerian university hospital, and to evaluate the prevalence of vancomycin-resistant enterococci (VRE) and the clonal cluster present in this country. METHODS: Patients who presented at Annaba University Hospital with Enterococcus infections were prospectively included over a 1-y period (2010). All Enterococcus sp. isolated were characterized by antibiotic resistance, van and erm genes, repetitive sequence-based polymerase chain reaction (rep-PCR), multi-locus sequence typing (MLST), and virulence genes. RESULTS: A total of 125 Enterococcus isolates recovered from 125 patients (59% female; median age 54 y, range 2-86 y) were studied. No differences in epidemiological data were observed between infections by Enterococcus faecalis vs Enterococcus faecium. However a high proportion of E. faecium were resistant to ampicillin (95%). The prevalence of VRE, corresponding to 4 vanC1-Enterococcus gallinarum, was 3.2%. A high level of genomic diversity among strains was noted, with the importance of sequence type (ST) 78 (which belongs to clonal complex (CC) 17) in E. faecium and ST317 and CC2 in E. faecalis. CONCLUSIONS: This first study on enterococci isolated in Algeria shows the low prevalence of VRE, but the presence of clonal complexes linked to VRE and vancomycin-sensitive enterococci associated with hospital infections. Moreover the high level of macrolide resistance and/or ampicillin resistance in E. faecium suggests close monitoring of the epidemiology of these strains.

Dissemination of OXA-48- and NDM-1-Producing Enterobacterales Isolates in an Algerian Hospital.

Multidrug-resistant (MDR) Enterobacterales remain an increasing problem in Algeria, notably due to the emergence of carbapenemase producers. We investigated the molecular characteristics of carbapenem-resistant Enterobacterales isolates recovered from outpatients and inpatients in Eastern Algeria. Non-repetitive Enterobacterales with reduced susceptibility to carbapenems were consecutively collected from clinical specimens in Annaba University Hospital (Algeria) between April 2016 and December 2018. Isolates were characterized with regard to antibiotic resistance, resistome and virulome content, clonality, and plasmid support. Of the 168 isolates analyzed, 29 (17.3%) were carbapenemase producers and identified as K. pneumoniae (n = 23), E. coli (n = 5), and E. cloacae (n = 1). blaOXA-48 was the most prevalent carbapenemase-encoding gene (n = 26/29), followed by blaNDM-1 gene (n = 3/29). K. pneumoniae isolates harbored some virulence traits (entB, ugeF, ureA, mrkD, fimH), whereas E. coli had a commensal origin (E, A, and B1). Clonality analysis revealed clonal expansions of ST101 K. pneumoniae and ST758 E. coli. Plasmid analysis showed a large diversity of incompatibility groups, with a predominance of IncM (n = 26, 89.7%). A global dissemination of OXA-48-producing Enterobacterales in the Algerian hospital but also the detection of NDM-1-producing E. coli in community settings were observed. The importance of this diffusion must be absolutely investigated and controlled.

First Clinical Cases of KPC-2-Producing Klebsiella pneumoniae ST258 in Algeria and Outbreak of Klebsiella pneumoniae ST101 Harboring blaOXA-48 Gene in the Urology Department of Annaba Hospital.

Objectives: The aim of this study was to characterize the molecular mechanisms of carbapenem resistance in Klebsiella pneumoniae isolated from the urology department of Annaba hospital, Algeria. Methods: Between January 2015 and September 2017, 14 carbapenem-resistant K. pneumoniae strains were isolated during routine surveillance work at Ibn Roched hospital of Annaba, Algeria, from the urology department. Theses strains were recovered, and carbapenem resistance mechanisms were investigated. The strains were identified by using matrix-assisted laser desorption and ionization time-of-flight mass spectrometry. Antibiotic susceptibility was assessed by using the Kirby-Bauer method, whereas minimum inhibitory concentration of imipenem/ertapenem and colistin was determined by Etest and broth microdilution methods, respectively. Carbapenem resistance determinants were studied by using PCR and sequencing methods and analyzed by BLAST against the Antibiotic Resistance Gene-ANNOTation (ARG-ANNOT) database. Clonal relationship of strains was performed by using multilocus sequence typing (MLST). Transferability of carbapenem resistance genes was assessed by conjugation and transformation experiments. Results: Fourteen carbapenem-resistant K. pneumoniae isolates were found to be resistant to the eight ß-lactam antibiotics tested (except to imipenem for two isolates). Carbapenemase production was positive for all isolates. Molecular characterization revealed that blaKPC-2 and blaOXA-48 genes were detected in 3 (21.4%) and 11 isolates (78.6%), respectively. Other ß-lactamases genes were identified, including blaCTX-M-15, blaSHV-1-or 12, and blaTEM-1. MLST revealed that the 14 isolates belonged to 2 different sequence types (STs), including ST101 (11 OXA-48-producing K. pneumoniae) and ST258 (3 KPC-2-producing K. pneumoniae). PCR amplifications for blaKPC-2 and blaOXA-48 carbapenemases genes performed on extracted plasmids, showed positive results, suggesting that both carbapenemase genes were probably borne by plasmids. Conclusion: We report here the first identification of KPC-2-producing K. pneumoniae ST258 in Algerian hospitals and an outbreak of OXA-48-producing K. pneumoniae isolates ST101 in the urology department of Ibn Roched hospital located in Annaba, Algeria.

Outbreak of an armA methyltransferase-producing ST39 Klebsiella pneumoniae clone in a pediatric Algerian Hospital.

Here we report an outbreak of Klebsiella pneumoniae infections harboring extended spectrum ß-lactamases (ESBL) and armA 16Sr RNA methylase that were detected in pediatric and neonatal intensive care units during the 2010 and 2011 surveys of 100 clinical strains of K. pneumoniae from Annaba hospitals in Algeria. Antibiotic susceptibility testing was performed using the disk diffusion method. Minimum inhibitory concentrations of three classes of antibiotics were determined using the E. test. Standard polymerase chain reaction amplification and sequencing were performed using primers targeting ESBL, 16S ribosomal RNA (rRNA) methyltransferases, aminoglycoside-modifying enzymes (AMEs), and quinolone encoding genes. Clonal relationships among the clinical isolates were performed using multilocus sequence typing. From our clinical isolates, we found high rates of antimicrobial resistance that were linked to the presence of different ESBL encoding genes and AMEs, including 23 strains that harbored several ESBL encoding genes along with the 16S rRNA methyltransferase armA. Among these isolates, we identified a cluster of eight isolates of the ST39 clone between February and June 2010 in a pediatric ward, suggesting that an outbreak had occurred during this period. In conclusion, the emergence of multidrug-resistant clones, which were likely responsible for a nosocomial outbreak, is worrying because there are already limited options in those critical situations. Finally, we believe that surveillance should be implemented to monitor the risk of emergence and spread of carbapenemases in Algeria.

Prevalence and characterization of extended spectrum beta-lactamase-producing Enterobacter cloacae strains in Algeria.

INTRODUCTION: Expended spectrum ß-lactamase (ESBL)-producing Enterobacter cloacae is an important nosocomial pathogen. In this study, the prevalence and the molecular epidemiology of ESBL producing E. cloacae strains isolated from various hospitals in Annaba, Algeria were investigated. METHODOLOGY: The study involved 63 isolates of E. cloacae obtained during 2009 at the four hospitals in Annaba. The detection of ESBL was performed using the double-disk synergy test and the combined disk test. Minimum inhibitory concentrations (MICs) were determined using the agar dilution method. The presence of bla(CTX-M), bla(SHV), bla(TEM), and bla(DHA) ß-lactamase genes was evaluated by PCR, and genomic typing was determined by pulsed-field gel electrophoresis (PFGE) analysis. The clinical and microbiological data were entered into the EpiI Info database. RESULTS: Thirty isolates (47.6%) had an ESBL phenotype. Bla(CTX-M) group1 (76%); bla(TEM) (70%) were the most prevalent, followed by bla(DHA) (16.6%) and bla(SHV) (10%). Eighteen strains expressed at least two bla genes. MICs revealed a high level of resistance to cefotaxime, ceftazidime, and cefepime. PFGE revealed an epidemic clonal dissemination of these isolates. Various risk factors associated with the occurrence of ESBL-producing E. cloacae were detected. CONCLUSIONS: A higher frequency of ESBL-producing isolates and a diversity of ß-lactamases were detected among ESBL-producing E. cloacae; these resulted from an epidemic clonal dissemination and high transference of ESBL genes between bacteria in hospital settings. Strict measures will be required to control the further spread of these pathogens in hospital settings.