Molecular characterization of carbapenem-resistant Enterobacterales in thirteen tertiary care hospitals in Saudi Arabia

Genomic analysis of extensively drug resistant (XDR) Klebsiella pneumoniae high-risk clone ST14 co-harboring blaNDM and blaOXA-48 recovered from Saudi Arabia

BACKGROUND

This study presents a comprehensive genomic analysis of NDM and OXA-48-producing Klebsiella pneumoniae in the Western region of Saudi Arabia, traversed by tens of millions of Muslims from various countries annually. This significant influx of visitors invariably leads to the spread and diversity of MDR bacteria.

METHODS

Genome sequencing was performed using MiSeq system of 29 CPKP isolates that were NDM and OXA-48-positive isolated from nosocomial infections and demonstrated resistance to most antibiotics, including carbapenems.

RESULTS

WGS analysis showed that 12 (41.3%) isolates co-harbored blaOXA-48,blaCTX-M-15 and blaNDM genes. Notably, 16 (55.1%) isolates were identified as high-risk clone ST14, with 50% of these isolates co-harbored blaOXA-48, blaNDM and blaCTX-M-15 genes. All ST14 isolates were identified as capsular genotype KL2 and O1/O2v1 antigen with yersiniabactin locus ypt 14 carried by ICEKp5. The two isolates were identified as ST2096/KL64 hypervirulent K. pneumoniae (hvKp) clone harboring several virulence factors, including the regulator of the mucoid phenotype rmpA2 and aerobactin (iuc-1). Interestingly, two of the hvKp ST383/KL30 isolates were resistant to all tested antimicrobials except colistin and tigecycline, and simultaneously carried numerous ESBLs and carbapenemase genes. These isolates also harbor several virulence factors such as rmpA1, rmpA2, carried on KpVP-1, and aerobactin (iuc-1).

CONCLUSION

this study provides insights into the spread and prevalence of high-risk clones of CPKP in the Western region of Saudi Arabia. The ST14 high-risk clone appears to be the predominant CPKP clone in this region, posing a significant threat to public health. This study also reports the presence of two globally disseminated hypervirulent K. pneumoniae (hvKp) clones, namely ST2096 and ST383. Therefore, it is essential to improve surveillance and implement strict infection control measures in this region, which receives a substantial number of visitors to effectively monitor and reduce the spread of high-risk clones of antimicrobial-resistant bacteria, including CPKP.

Molecular Screening of Carbapenem-Resistant K. pneumoniae (CRKP) Clinical Isolates for Concomitant Occurrence of Beta-Lactam Genes (CTX-M, TEM, and SHV) in the Kingdom of Bahrain

The emergence of extended-spectrum β-lactamase-producing Klebsiella pneumoniae, including CRKP infections, has resulted in significant morbidity and mortality worldwide. We aimed to explore the presence of bla genes (CTX-M, TEM, and SHV) in CRKP isolates. A total of 24 CRKP isolates were randomly selected from the Salmaniya Medical Complex Microbiology Laboratory. These isolates, which were positive for carbapenemases, were further explored for CTX-M, TEM, and SHV genes using PCR. All the CTX-M PCR amplicons were sent for sequencing. To determine genetic relatedness, molecular typing by ERIC-PCR was performed. The bla gene testing demonstrated that a significant proportion of these isolates harbored SHV, CTX-M, and TEM genes (100%, 91.6%, and 45.8%), respectively. Bioinformatic analyses confirmed CTX-M-15 in these isolates. ERIC-PCR analysis showed three clusters demonstrating genetic relatedness. The study findings reveal the concomitant carriage of the SHV and CTX-M-15 and a comparatively lower carriage of TEM genes in CRKP isolates. Our findings highlight the significance of routinely reporting the presence of antibiotic resistance genes along with regular antibiotic sensitivity reports, as this will aid clinicians in prescribing appropriate antibiotics.

Klebsiella pneumoniae bacteraemia epidemiology: resistance profiles and clinical outcome of King Fahad Medical City isolates, Riyadh, Saudi Arabia

BACKGROUND AND OBJECTIVES

Klebsiella pneumoniae (K. pneumoniae) is the second leading cause of community-acquired and hospital-acquired gram-negative bloodstream infection (BSI). This study aimed to assess the epidemiological and microbial-resistance characteristics and clinical factors associated with K. pneumoniae BSI in Saudi Arabia.

MATERIALS AND METHODS

Data of 152 K. pneumoniae isolates diagnosed between January 2019 and January 2020 at King Fahad Medical City, Riyadh, Saudi Arabia were evaluated retrospectively. Clinical records of the patients were collected and analysed statistically.

RESULTS

In total, 152 cases of K. pneumoniae BSI were identified. Adult patients (66.4%) were at a higher risk of developing the infection than paediatric patients (33.6%). The rate of infection was slightly higher in women than in men. Neurological disorders were the predominant underlying conditions for the acquisition of K. pneumoniae BSI, at all ages. Most of the deceased patients were adults with multi-organ dysfunction. Klebsiella pneumoniae showed disturbing resistance to amoxicillin-clavulanate and cefuroxime (72.4%), ceftazidime (67.8), cephalothin (76.3%), and to Carbapenems (36.1%).

CONCLUSIONS

The impact of K. pneumoniae BSI was seen not only at the patient level, but also at the community level, and was related to multi-drug resistant infection. These findings provide a better understanding of microbial resistance and its association with patient clinical outcomes.

An Overview of Antimicrobial Resistance in Saudi Arabia (2013-2023) and the Need for National Surveillance

Antimicrobial resistance (AMR) is a well-recognized global threat. The World Health Organization (WHO) issued a report ranking the critical types of bacterial resistance that need to be monitored. Several studies from individual institutions in Saudi Arabia have reported rates of antimicrobial resistance using automated methods. However, no national surveillance study has been conducted to date using gold standard methods for antimicrobial susceptibility testing. This review summarizes AMR rates for major bacterial pathogens in Saudi Arabia and provides a justification for the need for a national surveillance project. In Saudi Arabia, AMR rates for both Gram-positive and Gram-negative bacteria are on the rise. Surveillance studies help identify AMR trends and emergence of outbreaks. The WHO has started a program, the Global Antimicrobial Resistance Surveillance System (GLASS), encouraging its member states, including Saudi Arabia, to conduct antimicrobial surveillance studies to estimate AMR rates worldwide. Of the microbiological methods used to test antimicrobial susceptibility, only broth microdilution (BMD) is considered the "gold standard." As AMR studies in Saudi Arabia are sparse, mostly limited to single centers and were conducted using automated methods, a national AMR surveillance project is needed to evaluate the current status and to inform stewardship decisions.

Cracking the Code: Unveiling the Diversity of Carbapenem-Resistant Klebsiella pneumoniae Clones in the Arabian Peninsula through Genomic Surveillance

The rise of antimicrobial resistance is a global challenge that requires a coordinated effort to address. In this study, we examined the genetic similarity of carbapenem-resistant Klebsiella pneumoniae (CRKP) in countries belonging to the Gulf Cooperation Council (GCC) to gain a better understanding of how these bacteria are spreading and evolving in the region. We used in silico genomic tools to investigate the occurrence and prevalence of different types of carbapenemases and their relationship to specific sequence types (STs) of CRKP commonly found in the region. We analyzed 720 publicly available genomes of multi-drug resistant K. pneumoniae isolates collected from six GCC countries between 2011 and 2020. Our findings showed that ST-14 and ST-231 were the most common STs, and 51.7% of the isolates carried bla_OXA-48-like genes. Additionally, we identified rare carbapenemase genes in a small number of isolates. We observed a clonal outbreak of ST-231 in Oman, and four Saudi isolates were found to have colistin resistance genes. Our study offers a comprehensive overview of the genetic diversity and resistance mechanisms of CRKP isolates in the GCC region that could aid in developing targeted interventions to combat this pressing global issue.

A Narrative Review of Healthcare-Associated Gram-Negative Infections Among Pediatric Patients in Middle Eastern Countries

INTRODUCTION

Gram-negative bacteria (GNB) have become prominent across healthcare and community settings due to factors including lack of effective infection control and prevention (ICP) and antimicrobial stewardship programs (ASPs), GNB developing antimicrobial resistance (AMR), and difficulty treating infections. This review summarizes available literature on healthcare-associated infections (HAIs) in Middle Eastern pediatric patients.

METHODS

Literature searches were performed with PubMed and Embase databases. Articles not reporting data on GNB, HAIs, pediatric patients, and countries of interest were excluded.

RESULTS

The searches resulted in 220 publications, of which 49 met the inclusion criteria and 1 additional study was identified manually. Among 19 studies across Egypt reporting GNB prevalence among pediatric patients, Klebsiella species/K. pneumoniae and Escherichia coli were typically the most common GNB infections; among studies reporting carbapenem resistance and multidrug resistance (MDR), rates reached 86% and 100%, respectively. Similarly, in Saudi Arabia, Klebsiella spp./K. pneumoniae and E. coli were the GNB most consistently associated with infections, and carbapenem resistance (up to 100%) and MDR (up to 75%) were frequently observed. In other Gulf Cooperation Council countries, including Kuwait, Oman, and Qatar, carbapenem resistance and MDR were also commonly reported. In Jordan and Lebanon, E. coli and Klebsiella spp./K. pneumoniae were the most common GNB isolates, and AMR rates reached 100%.

DISCUSSION

This review indicated the prevalence of GNB-causing HAIs among pediatric patients in Middle Eastern countries, with studies varying in reporting GNB and AMR. Most publications reported antimicrobial susceptibility of isolated GNB strains, with high prevalence of extended-spectrum beta-lactamase-producing K. pneumoniae and E. coli isolates. A review of ASPs highlighted the lack of data available in the region.

CONCLUSIONS

Enhanced implementation of ICP, ASPs, and AMR surveillance is necessary to better understand the widespread burden of antimicrobial-resistant GNB and to better manage GNB-associated HAIs across Middle Eastern countries.

Early Years of Carbapenem-Resistant Enterobacterales Epidemic in Abu Dhabi

Recent studies showed that the current endemic of carbapenem-resistant Enterobacterales (CRE) in the Emirate of Abu Dhabi is dominated by highly resistant Klebsiella pneumoniae clones ST14, ST231, and CC147, respectively. In the absence of continuous, molecular typing-based surveillance, it remained unknown whether they lately emerged and rapidly became dominant, or they had been present from the early years of the endemic. Therefore, antibiotic resistance, the presence of carbapenemase and 16S methylase genes, and the sequence types of CRE strains collected between 2009 and 2015 were compared with those collected between 2018 and 2019. It was found that members of these three clones, particularly those of the most prevalent ST14, started dominating already in the very early years of the CRE outbreak. Furthermore, while severely impacting the overall antibiotic resistance patterns, the effect of these clones was not exclusive: for example, increasing trends of colistin or decreasing rates of tigecycline resistance were also observed among nonclonal isolates. The gradually increasing prevalence of few major, currently dominating clones raises the possibility that timely, systematic, molecular typing-based surveillance could have provided tools to public health authorities for an early interference with the escalation of the local CRE epidemic.

Evaluation of ceftazidime/avibactam for treatment of carbapenemase-producing carbapenem-resistant Enterobacterales with OXA-48 and/or NDM genes with or without combination therapy

Background

Carbapenem-resistant Enterobacterales (CRE) is an urgent public health threat of significant global concern. Few observational studies have evaluated the clinical outcomes for treatment of CRE harbouring OXA-48 or NDM genes with ceftazidime/avibactam. Previous findings showed lower 30 day mortality with ceftazidime/avibactam ranges between 8.3% and 22%.

Method

This single-centre retrospective cohort study included adult patients aged ≥18 years admitted to King Abdulaziz Medical City (KAMC) who had received ceftazidime/avibactam for at least 72 h for infections caused by CRE with genes encoding for carbapenemase production (CP-CRE).

Results

A total of 211 patients, mostly male (57%), having CP-CRE infections treated with ceftazidime/avibactam were included, with an average age of 62 years. More than 50% of patients were critically ill, for which 46% received invasive ventilation and 36% were on inotropes. The most frequent infectious disease was hospital/ventilator-acquired pneumonia with Klebsiella pneumoniae being the most frequent causative pathogen. The majority of isolates harboured OXA-48 (81%), followed by NDM ± OXA-48 (19%). The overall clinical cure and 30 day mortality was 78% and 21% respectively (stratified per gene: 79% and 21.6% for OXA-48 and 75% and 17.5% for NDM ± OXA-48).

Conclusions

This was the largest study that evaluated clinical outcomes associate with CP-CRE harbouring OXA-48 gene infections treated with ceftazidime/avibactam. Clinical cure and 30 day mortality were consistent with those of previous studies. Findings suggested that combination therapy with ceftazidime/avibactam had no direct impact on clinical outcomes for CP-CRE with OXA-48.

Extended Spectrum- and Carbapenemase-Based β-Lactam Resistance in the Arabian Peninsula-A Descriptive Review of Recent Years

Antimicrobial resistance (AMR) is a global problem that also includes countries of the Arabian Peninsula. Of particular concern, is the continuing development of extended-spectrum β-lactamases (ESBLs) in the countries of this region. Additionally, antibiotic treatment options for ESBL-producing bacteria are becoming limited, primarily due to the continuing development of carbapenem resistance (CR), carbapenems being frequently used to treat such infections. An overview of recent publications (2018-2021) indicates the presence of ESBL and/or CR in patients and hospitals in most countries of the Arabian Peninsula, although the delay between microbial isolation and publication inevitably makes an accurate analysis of the current situation rather difficult. However, there appears to be greater emphasis on CR (including combined ESBL and CR) in recent publications. Furthermore, although publications from Saudi Arabia are the most prevalent, this may simply reflect the increased interest in ESBL and CR within the country. Enhanced ESBL/CR surveillance is recommended for all countries in the Arabian Peninsula.

The first nation-wide surveillance of carbapenem resistant Enterobacterales in the United Arab Emirates - increased association of Klebsiella pneumoniae CC14 clone with Emirati patients

OBJECTIVES

To assess the current prevalence, distribution, and main clonal types of carbapenem resistant Enterobacterales (CRE) in the United Arab Emirates.

METHODS

504 CRE collected over a 9-month period in 15 hospitals were studied. Antibiotic susceptibility, and the presence of common carbapenemase, 16S methylase and mobile colistin resistance genes were assessed. Selected strains forming larger clusters by pulsed field gel electrophoresis were subjected to whole genome sequencing to identify their sequence types and core genome MLST.

RESULTS

Strains expressing OXA and NDM type carbapenemases, and 16S methylases were present in all major hospitals. Considerable inter-hospital differences were noticed suggesting the role of specific clones. Three major Klebsiella pneumoniae clones (CC14, ST231 and CC147) were identified accounting for 48.6% of all CRE. All clones were significantly more resistant than sporadic isolates. CC14 strains exhibited a significant association with Emirati patients.

CONCLUSIONS

Nearly half of CRE infections in the country are due to a limited number of clones. The data indicate the possibility of inter-hospital transmission combined in some hospitals with inadequate stewardship practices. The study also revealed an association of the largest, most resistant clone (CC14) with Emirati patients. The specific reasons of it should be clarified by further investigations.

Ceftazidime-Avibactam versus Colistin for the Treatment of Infections Due to Carbapenem-Resistant Enterobacterales: A Multicenter Cohort Study

Background

The aim of this study was to compare the safety and effectiveness of ceftazidime-avibactam (CAZ-AVI) to colistin-based regimen in the treatment of infections caused by carbapenem-resistant Enterobacterales (CRE).

Methods

This was a retrospective, multicenter, observational cohort study of inpatients who received either CAZ-AVI or intravenous colistin for treatment of infections due to CRE. The study was conducted in 5 tertiary care hospitals in Saudi Arabia. Main study outcomes included in-hospital mortality, clinical cure at end of treatment, and acute kidney injury (AKI). Univariate analysis and multivariate logistic regression model were conducted to assess the independent impact of CAZ-AVI on the clinical outcome.

Results

A total of 230 patients were included in this study: 149 patients received CAZ-AVI and 81 patients received colistin-based regimen. Clinical cure (71% vs 52%; P = 0.004; OR, 2.29; 95% CI, 1.31–4.01) was significantly more common in patients who received CAZ-AVI. After adjusting the difference between the two groups, treatment with CAZ-AVI is independently associated with clinical cure (adjusted OR, 2.75; 95% CI, 1.28–5.91). In-hospital mortality (35% vs 44%; P = 0.156; OR, 0.67; 95% CI, 0.39–1.16) was lower in patients who received CAZ-AVI but the difference was not significant. AKI (15% vs 33%; P = 0.002; OR, 0.37; 95% CI, 0.19–0.69) was significantly less common in patients who received CAZ-AVI.

Conclusion

CAZ-AVI is associated with higher rate of clinical cure and lower rate of AKI compared to colistin. Our findings support the preferential use of CAZ-AVI over colistin-based regimen for treating these infections.

Diversity of carbapenem-resistant Klebsiella pneumoniae ST14 and emergence of a subgroup with KL64 capsular locus in the Arabian Peninsula

To understand the reasons of successful spread of carbapenem-resistant Klebsiella pneumoniae ST14 (CRKP-ST14) in countries of the Arabian Peninsula, the resistome, capsular locus, carbapenemase carrying plasmid types, and core genome of isolates from the region were compared to global isolates. Thirty-nine CRKP-ST14 strains isolated from 13 hospitals in the United Arab Emirates, Bahrain, and Saudi Arabia were selected for whole genome sequencing on Illumina MiSeq platform based on the variety of carbapenemase genes carried and plasmids bearing these genes. Their resistome, capsular locus, and core genome MLST were compared to 173 CRKP-ST14 genomes available in public databases. The selected 39 CRKP-ST14 produced either NDM-1, OXA-48, OXA-162, OXA-232, KPC-2, or co-produced NDM-1 and an OXA-48-like carbapenemase. cgMLST revealed three clusters: 16 isolates from five UAE cities (C1), 11 isolates from three UAE cities and Bahrain (C2), and 5 isolates from Saudi Arabia (C3), respectively, and seven singletons. Resistance gene profile, carbapenemase genes, and their plasmid types were variable in both C1 and C2 clusters. The majority of CRKP-ST14 had KL2, but members of the C2 cluster and two further singletons possessed KL64 capsular locus. Based on cgMLST comparison of regional and global isolates, CRKP-ST14 with KL64 from four continents formed a distinct cluster, suggesting a recent emergence and spread of this variant. Our findings confirmed clonal transmission coupled with likely horizontal gene transfer in carbapenem-resistant Klebsiella pneumoniae ST14. Dissemination of this genetically flexible, highly resistant clone warrants further monitoring.