Resistant Klebsiella Research Articles

Phenotypic investigation of Beta–Lactamase enzymes in multidrug resistant Klebsiella Pneumoniae clinically isolated in Diyala City /Iraq

Phenotypic investigation of Beta–Lactamase enzymes in multidrug resistant Klebsiella Pneumoniae clinically isolated in Diyala City /Iraq

Novel functions of o-cymen-5-ol nanoemulsion in reversing colistin resistance in multidrug-resistant Klebsiella pneumoniae infections

Multidrug resistance (MDR) Klebsiella pneumoniae (K. pneumoniae) is a major emerging threat to human health, and leads to very high mortality rate. The effectiveness of colistin, the last resort against MDR Gram-negative bacteria, is significantly compromised due to the widespread presence of plasmid- or chromosome-mediated resistance genes. In this study, o-cymen-5-ol has been found to greatly restore colistin sensitivity in MDR K. pneumoniae. Importantly, this compound does not impact bacterial viability, induce resistance, or cause any noticeable cell toxicity. Various routes disclosed the potential mechanism of o-cymen-5-ol potentiating colistin activity against MDR K. pneumoniae. These include inhibiting the activity of plasmid-mediated mobile colistin resistance gene (mcr-1), accelerating lipopolysaccharide (LPS) − mediated membrane damage, and promoting the ATP-binding cassette (ABC) transporter pathway. To enhance the administration and bioavailability of o-cymen-5-ol, a nanoemulsion has been designed, which significantly improves the loading efficiency and solubility of o-cymen-5-ol, resulting in antimicrobial potentiation of colistin against K. pneumoniae infection. This study has revealed a new understanding of the o-cymen-5-ol nanoemulsion as a means to enhance the effectiveness of colistin against resistant factors. The finding also suggests that o-cymen-5-ol nanoemulsion could be a promising approach in the development of potential treatments for multidrug-resistant Gram-negative bacterial infections.

CRISPR-Cas system in multi drugs resistant Klebsiella pneumoniae from different clinical samples and its correlation with antibiotic-resistant genes in Mosul city / Iraq

CRISPR-Cas system in multi drugs resistant Klebsiella pneumoniae from different clinical samples and its correlation with antibiotic-resistant genes in Mosul city / Iraq

Fitness cost of tet(A) type I variant-mediated tigecycline resistance in Klebsiella pneumoniae

ObjectiveThe aim of the present study is to explore the impact of the tet(A) type I variant (tetA-v1) on its fitness effect in Klebsiella pneumoniae. MethodsClinical K. pneumoniae strains were utilized as parental strains to generate strains carrying only the plasmid vector (pBBR1MCS-5) or the tetA-v1 recombinant plasmid (ptetA-v1). Antimicrobial susceptibility testing was conducted to estimate the contribution of tetA-v1 to drug resistance. Plasmid stability was evaluated by serial passage over 10 consecutive days in the absence of tigecycline. Biological fitness was examined through growth curve analysis, in vitro competition assays and a neutropenic mouse thigh infection model. ResultsA 2–4-fold increase in tigecycline MIC was observed following the acquisition of tetA-v1. Without tigecycline treatment, the stability of ptetA-v1 plasmids has been decreasing since day 1. The ptetA-v1 plasmid in Kp89, Kp91, and Kp93 exhibited a decrease of about 20% compared to the pBBR1MCS-5 plasmid. The acquisition of the tetA-v1 gene could inhibit the growth ability of K. pneumoniae strains both in vitro and in vivo. tetA-v1 gene imposed a fitness cost in K. pneumoniae, particularly in the CRKP strain Kp51, with a W value of approximately 0.56. ConclusionThe presence of tetA-v1 is associated with a significant fitness cost in K. pneumoniae in the absence of tigecycline, both in vitro and in vivo.

Global prevalence of mutation in the mgrB gene among clinical isolates of colistin-resistant Klebsiella pneumoniae: a systematic review and meta-analysis.

Colistin is used as a last resort for managing infections caused by multidrug-resistant bacteria. However, the high emergence of colistin-resistant strains has restricted the clinical use of this antibiotic in the clinical setting. In the present study, we evaluated the global prevalence of the mutation in the mgrB gene, one of the most important mechanisms of colistin resistance in Klebsiella pneumoniae. Several databases, including Scopus, Medline (via PubMed), and Web of Science, were searched (until August 2023) to identify those studies that address the mgrB mutation in clinical isolates of K. pneumoniae. Using Stata software, the pooled prevalence of mgrB mutation and subgroup analyses for the year of publication, country, continent, mgrB mutation types, and detection methods of mgrB mutation were analyzed. Out of the 115 studies included in the analysis, the prevalence of mgrB mutations in colistin-resistant K. pneumoniae isolates was estimated at 65% of isolates, and mgrB variations with insertional inactivation had the highest prevalence among the five investigated mutations with 69%. The year subgroup analysis indicated an increase in mutated mgrB from 46% in 2014 to 61% in 2022. Europe had the highest prevalence of mutated mgrB at 73%, while Africa had the lowest at 54%. Mutations in the mgrB gene are reported as one of the most common mechanisms of colistin resistance in K. pneumoniae, and the results of the present study showed that 65% of the reported colistin-resistant K. pneumoniae had a mutation in this gene.

AcrAB-TolC efflux pump overexpression and tet(A) gene mutation increase tigecycline resistance in Klebsiella pneumoniae.

Tigecycline-non-susceptible Klebsiella pneumoniae (TNSKP) is increasing and has emerged as a global public health issue. However, the mechanism of tigecycline resistance remains unclear. The objective of this study was to investigate the potential role of efflux pump system in tigecycline resistance. 29 tigecycline-non-susceptible Klebsiella pneumoniae (TNSKP) strains were collected and their minimum inhibitory concentrations (MIC) were determined by the broth microdilution method. The ramR, acrR, rpsJ, tet(A), and tet(X) were amplified by polymerase chain reaction (PCR). The mRNA expression of different efflux pump genes and regulator genes were analyzed by real-time PCR. Additionally, KP14 was selected for genome sequencing. KP14 genes without acrB, oqxB, and TetA were modified using suicide plasmids and MIC of tigecycline of KP14 with target genes knocked out was investigated. It was found that MIC of tigecycline of 20 out of the 29 TNSKP strains decreased by over four folds once combined with phenyl-arginine-β-naphthylamide dihydrochloride (PaβN). Most strains exhibited upregulation of AcrAB and oqxAB efflux pumps. The strains with acrB, oqxB, and tetA genes knocked out were constructed, wherein the MIC of tigecycline of KP14∆acrB and KP14∆tetA was observed to be 2µg/mL (decreased by 16 folds), the MIC of tigecycline of KP14ΔacrBΔTetA was 0.25µg/mL (decreased by 128 folds), but the MIC of tigecycline of KP14∆oqxB remained unchanged at 32µg/mL. The majority of TNSKP strains demonstrated increased expression of AcrAB-TolC and oqxAB, while certain strains showed mutations in other genes associated with tigecycline resistance. In KP14, both overexpression of AcrAB-TolC and tet(A) gene mutation contributed to the mechanism of tigecycline resistance.

Whole genome sequencing analysis of seven unknown resistance mechanisms of carbapenem-resistant Klebsiella pneumoniae strains resistance to ceftazidime-avibactam.

To investigate alternative resistance mechanisms among seven ceftazidime-avibactam (CZA)-resistant carbapenem-resistant Klebsiella pneumoniae (CRKP) strains lacking common antimicrobial resistance genes (ARGs) using whole genome sequencing. ARG and virulence factors (VFs) were screened using the ARG database CARD and the VF database, respectively, and identified using genomic annotation data with BLAST+. Six strains were ST11 sequence types (STs), and one was ST2123. ST11 strains harbored more ARGs than the ST2123 strains. All seven strains carried multiple ARGs with efflux-mediated antibiotic resistance, including oqxA, oqxB, tet (A), qacEdltal, CRP, H-NS, Kpn-E, F, G, H, acrA, LptD, acrB, acrD, cpxA, mdtB, and mdtC. These efflux-mediated ARGs were identified in most strains and even all strains. Whole genome sequencing revealed that the ST11 strain carried multiple potential prophages, genomic islands, and integrative and conjugative elements, while the ST2123 strain carried an independent potential prophages and a genomic island. Whole genome sequencing analysis revealed that these seven CZA-resistant CRKP strains lacking common ARGs exhibited efflux-mediated antibiotic resistance-associated ARGs. The main mechanism by which CRKP resists CZA is antibiotic inactivation. Except for tet (A), no ARGs and validation experiments related to efflux were found. This study's results provide a new possibility for the resistance mechanism of CRKP to CZA, and we will verify this conclusion through experiments in the future.

Transcriptomic responses of extensively drug resistant Klebsiella pneumoniae to N-acetyl cysteine reveals suppression of major biogenesis pathways leading to bacterial killing and biofilm eradication.

Carbapenemase-producing Klebsiella pneumoniae is categorized as a "critical global priority-one" pathogen by WHO and new and efficient treatment options are warranted. This study aims to assess the antibacterial and antibiofilm potential of N-acetyl cysteine (NAC), against clinical isolates of extensively drug resistant (XDR) K. pneumoniae and elucidate the mechanism of killing. XDR-K. pneumoniae were isolated from patients admitted to Madras Medical Mission Hospital, India. Antibiofilm activity of NAC was checked using in vitro continuous flow model and RNA sequencing was done using Illumina Novoseq. Data quality was checked using FastQC and MultiQC software. Our findings revealed that NAC at a concentration of 100 mg/ml was safe, and could inhibit the growth and completely eradicate mature biofilms of all XDR-K. pneumoniae isolates. Transcriptomic responses in XDR-K. pneumoniae to NAC showed significant downregulation of the genes associated with crucial biogenesis pathways, including electron transport chain and oxidoreductase activity besides a specific cluster of genes linked to ribosomal proteins. Our results indicate that NAC kills the XDR- K. pneumoniae clinical isolates by shutting the overall metabolism and, hence, successfully eradicate in vitro biofilms formed on catheters.

Linoleic acid acts as a potential anti-virulence agent in Klebsiella pneumoniae.

The rise in antimicrobial resistance among bacterial pathogens is a global concern, and anti-virulence therapy may be an alternative strategy to address the issue. Multidrug resistant (MDR) hypervirulent Klebsiella pneumoniae (HvKp) is known to be associated with healthcare associated infections. These are often challenging to treat and here anti-virulence therapy may be a treatment option. The study of anti-virulence compounds against HvKp by in-silico prediction, in-vitro experiments and in-vivo assay enables to determine which anti-virulence compounds are suitable for an alternative approach MDR HvKp. Modeling of the proteins, ligand binding and molecular docking were performed targeting different hypervirulence genes viz., rmpA, rmpA2 and, iroC by in-silico analysis using different bioinformatics tool and software. Minimum inhibitory concentration (MIC) was determined for six anti-virulence compounds; curcumin, eugenol, reserpine, linoleic acid, ε-anethole, and α-thujone by standard protocol. Quantitative real-time PCR was performed selecting two isolates harboring rmpA, rmpA2 and iroC genes. Galleria mellonella larva killing assay was used for in-vivo experiment. In-silico analysis observed that linoleic acid could be the best fit in comparison with the other compounds. None of the anti-virulence compounds showed any inhibitory activity and upon transcriptional expression analysis of the hypervirulence genes; rmpA was marginally increased for both the isolates when linoleic acid exposure was given. In-vivo study revealed that linoleic acid and reserpine showed anti-virulence activity.

Molecular and bacteriological investigations for the co-existence CRISPR/Cas system and β-lactamases of types extended-spectrum and carbapenemases in Multidrug, extensive drug and Pandrug-Resistant Klebsiella pneumoniae

The recent approach towards combating the antimicrobial resistance has led to the use of Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) and associated sequence to overcome the challenges of antimicrobial resistance. Thus, this study aimed to detect the underlying resistance mechanisms such as ESBLs and carbapenemases and whether there is a correlation between multidrug, extensive drug and pan drug resistance and the occurrence of CRISPR loci. A total of one hundred study isolates were subjected to antimicrobial susceptibility testing using the AST card of the Vitek technique to detect resistance patterns involving ESBLs and carbapenemase (CRE). An investigation of the genes encoding CRISPR/Cas systems using PCR was achieved. Out of 81 (81.0%) resistant Klebsiella pneumoniae isolates, 71 (71%) and 21 (21.0%) produced ESBLs and carbapenemases, respectively. Also, 53 (53.0%), 19 (19.0%) and 9 (9.0%) were MDR, XDR, and PDR respectively. It was noted that Cas1, Cas3, CRISPR1, CRISPR2 and CRISPR3 were positive in 38 (38.0%) of the isolates, while CRISPR1 for incomplete CRISPR1-Cas systems alone was detected in 78 (78.0%). Further, the number of intact CRISPR1, intact CRISPR2 and intact CRISPR3 types were 7 (27.0%), 34 (34%) and 18 (18.0%) respectively. It is concluded that antibiotic resistance levels were inversely correlated with the existence of CRISPR/Cas systems. The absence of the CRISPR/Cas system increases the prevalence of MDR, XDR and PDR in ESBL and carbapenem-producing Klebsiella pneumoniae. With the increase in the degree of antibiotic resistance (MDR, XDR to PDR), the occurrence ratio of the (CRISPR)/CRISPR-associated sequence decreased.

Evolution of Antimicrobial Resistance in Klebsiella pneumoniae over 3 Years (2019-2021) in a Tertiary Hospital in Bucharest, Romania.

The antimicrobial resistance (AMR) of Klebsiella pneumoniae recorded a steep upward trend over the last two decades, among which carbapenem-resistant Klebsiella pneumoniae (CRKP) is one of the most concerning strains considering the development and spread of AMR. The aim of this study was to analyze the evolution of AMR for Klebsiella pneumoniae and to describe the risk factors of AMR for Klebsiella pneumoniae, including the COVID-19 pandemic. We conducted a retrospective study on Klebsiella pneumoniae non-duplicative isolates collected from patients admitted to a tertiary hospital in Bucharest, Romania, from January 2019 to December 2021. We evaluated AMR changes by comparing resistance between 2019 and the mean of 2020-2021. The rates of AMR increased for third-generation cephalosporins, carbapenems, aminoglycosides, fluoroquinolones, and colistin and decreased for trimethoprim/sulfamethoxazole (TMP/SMX), 45.7% in 2019 vs. 28.3% in 2021. A longer length of hospital stay (ꭓ2 = 49.68, p < 0.01); recent antibiotic consumption, RR = 1.38, 95% CI [1.21, 1.57]; and recent contact with hospital settings, RR = 1.54, 95% CI [1.32, 1.8] were risk factors for multidrug-resistant (MDR) Klebsiella pneumoniae. The AMR of Klebsiella pneumoniae increased during 2020-2021 for most of the potential active antibiotics; only TMP/SMX resistance decreased, and it may represent a treatment option for CRKP or MDR Klebsiella pneumoniae infections. Decreasing the excessive use of antibiotics and the implementation of prevention and control measures in healthcare settings are mandatory for avoiding further increases in the AMR rate of Klebsiella pneumoniae.

Exploring the Ecological Distribution and Antibiotic Resistance Profiles of Klebsiella Species in Diverse Environmental Niches

Antimicrobial resistance is a growing problem in bacterial pathogens, particularly in hospital-acquired nosocomial infections. Klebsiella is an important pathogen that causes various infections in hospitalized immunocompromised patients. Therefore, this study aims to fill this knowledge gap and provide insights into the correct detection and antibiotic resistance pattern of these organisms. we will investigate the spread of pneumonia bacteria, Klebsiella, isolate and identify it from different environmental sites, including human, soil, and water, also study the characteristics of antibiotic resistance and find similarities and differences between bacterial isolates. Finally, we detect the associated antibiotics resistance gene (CTX-M), using the genetic RT-PCR method. The study provides valuable information on the prevalence of antibiotic resistant Klebsiella spp. in different clinical and environmental sites, which can help in the development of effective strategies to control the spread of these bacteria. The study found that among all 86 isolated strains of Klebsiella spp. it was found that K. pneumoniae represents the major abundant strain in both clinical and environmental samples by percentages 41.5% and 51.5% respectively. It concerns also the highest ESBL production 71.7%, along with 58% CTX-M gene expression

Ceftazidime-Avibactam resistance in clinical isolates of carbapenem-resistant Klebsiella pneumoniae: A phenotypic and genotypic analysis

ObjectiveTo find the prevalence of Ceftazidime-Avibactam (CAZ-AVI) resistant Klebsiella pneumoniae in clinical isolates and to determine the genes responsible for Ceftazidime-Avibactam resistance using PCR. MethodsA total of 89 carbapenem resistant Klebsiella pneumoniae from various clinical samples were included in the study. CAZ-AVI resistance was tested using E-test. CAZ-AVI resistant strains were subjected to conventional PCR for detection of carbapenamase genes blaNDM- 1, blaOXA-48, blaVIM, blaIMP, blaKPC. ResultsOf the 89 isolates screened for CAZ-AVI resistance, 45(50.5%) isolates were found to be resistant. 42 isolates were subjected to PCR for detection of β lactamase genes.34 isolates were positive for blaNDM-1 and all 42 isolates were positive for blaOXA-48. Co-expression of NDM-1 and OXA-48 was seen in 34 isolates. Sensitivity of mCIM test to identify a carbapenamse compared to PCR was 61.9%. Sensitivity of eCIM test to identify NDM-1 was 80%. ConclusionCAZ-AVI was effective in vitro in 49.4% of the isolates. Indicating that CAZ-AVI is a promising addition to antibiotics against CRE as well as a carbapenem sparing drug in ESBL producing organisms. β-Lactamase-related mutations are the main mechanism leading to CAZ-AVI resistance.

Could traces of fluoroquinolones in food induce ciprofloxacin resistance in Escherichia coli and Klebsiella pneumoniae? An in vivo study in Galleria mellonella with important implications for maximum residue limits in food.

We hypothesized that the residual concentrations of fluoroquinolones allowed in food (acceptable daily intake-ADIs) could select for ciprofloxacin resistance in our resident microbiota. We developed models of chronic Escherichia coli and Klebsiella pneumoniae infection in Galleria mellonella larvae and exposed them to ADI doses of ciprofloxacin via single dosing and daily dosing regimens. The emergence of ciprofloxacin resistance was assessed via isolation of the target bacteria in selective agar plates. Exposure to as low as one-tenth of the ADI dose of the single and daily dosing regimens of ciprofloxacin resulted in the selection of ciprofloxacin resistance in K. pneumoniae but not E. coli. This resistance was associated with cross-resistance to doxycycline and ceftriaxone. Whole genome sequencing revealed inactivating mutations in the transcription repressors, ramR and rrf2, as well as mutations in gyrA and gyrB. We found that ciprofloxacin doses 10-fold lower than those classified as acceptable for daily intake could induce resistance to ciprofloxacin in K. pneumoniae. These results suggest that it would be prudent to include the induction of antimicrobial resistance as a significant criterion for determining ADIs and the associated maximum residue limits in food.IMPORTANCEThis study found that the concentrations of ciprofloxacin/enrofloxacin allowed in food can induce de novo ciprofloxacin resistance in Klebsiella pneumoniae. This suggests that it would be prudent to reconsider the criteria used to determine "safe" upper concentration limits in food.

A challenging case of carbapenem resistant Klebsiella pneumoniae-related pyogenic liver abscess with capsular polysaccharide hyperproduction: a case report

BackgroundCarbapenem-resistant Klebsiella pneumoniae (CRKP) infections are a major public health problem, necessitating the administration of polymyxin E (colistin) as a last-line antibiotic. Meanwhile, the mortality rate associated with colistin-resistant K. pneumoniae infections is seriously increasing. On the other hand, importance of administration of carbapenems in promoting colistin resistance in K. pneumoniae is unknown.Case presentationWe report a case of K. pneumoniae-related pyogenic liver abscess in which susceptible K. pneumoniae transformed into carbapenem- and colistin-resistant K. pneumoniae during treatment with imipenem. The case of pyogenic liver abscess was a 50-year-old man with diabetes and liver transplant who was admitted to Abu Ali Sina Hospital in Shiraz. The K. pneumoniae isolate responsible for community-acquired pyogenic liver abscess was isolated and identified. The K. pneumoniae isolate was sensitive to all tested antibiotics except ampicillin in the antimicrobial susceptibility test and was identified as a non-K1/K2 classical K. pneumoniae (cKp) strain. Multilocus sequence typing (MLST) identified the isolate as sequence type 54 (ST54). Based on the patient’s request, he was discharged to continue treatment at another center. After two months, he was readmitted due to fever and progressive constitutional symptoms. During treatment with imipenem, the strain acquired blaOXA−48 and showed resistance to carbapenems and was identified as a multidrug resistant (MDR) strain. The minimum inhibitory concentration (MIC) test for colistin was performed by broth microdilution method and the strain was sensitive to colistin (MIC < 2 µg/mL). Meanwhile, on blood agar, the colonies had a sticky consistency and adhered to the culture medium (sticky mucoviscous colonies). Quantitative real-time PCR and biofilm formation assay revealed that the CRKP strain increased capsule wzi gene expression and produced slime in response to imipenem. Finally, K. pneumoniae-related pyogenic liver abscess with resistance to a wide range of antibiotics, including the last-line antibiotics colistin and tigecycline, led to sepsis and death.ConclusionsBased on this information, can we have a theoretical hypothesis that imipenem is a promoter of resistance to carbapenems and colistin in K. pneumoniae? This needs more attention.

Novel in-genome based analysis demonstrates the evolution of OmpK37, antimicrobial resistance gene from a potentially pathogenic pandrug resistant Klebsiella pneumoniae MS1 isolated from healthy broiler feces

Antimicrobial resistance transmission from farm animals to humans is a critical health concern and hence a detailed molecular surveillance is essential for tracking the spread and consequent evolution of antimicrobial resistance. In this study, a pan-drug resistant Klebsiella pneumoniae MS1 strain was isolated from a healthy broiler farm and studied. From the results of the study, MS1 was found to be is resistant to 18 tested antibiotics and has a high-risk to be pathogenic to humans with a probability of 0.80. The whole genome sequencing data of MS1 was used to predict the presence of antimicrobial resistance genes and pathogenicity. The genome analysis has revealed MS1 to have 34 AMR genes. Out of these, the AMR gene OmpK37 codes for an important protein involved in cell permeability and hence in antibiotic resistance. Further analysis was carried out by using an in-genome analysis method to understand the evolution of OmpK37 and the underlying reason for the emergence of resistance. From the detailed analysis, the current study could demonstrate for the first time the evolution of OmpK37 from OmpC. Though structurally OmpK37 was very similar to other porins present in MS1, it was found to have higher mutability as a distinguishing feature which makes it an important protein in monitoring the evolving resistances in microorganisms.

Molecular diversity of Klebsiella pneumoniae clinical isolates: antimicrobial resistance, virulence, and biofilm formation

One of the mechanisms responsible for antibiotic resistance in Klebsiella pneumoniae is the enzymes produced by the bacteria; another important mechanism is the ability to form biofilm. In this study, antibiotic resistance, genes associated with virulence, and biofilm-forming properties of K. pneumoniae strains were investigated. A total of 100 K. pneumoniae isolates were obtained from different clinical samples identified by Matrix-Assisted Laser Desorption/Ionization time-of-flight Mass Spectrometry. Antimicrobial susceptibility testing was performed with the Phoenix 100 apparatus. The biofilm forming properties of strains were determined by the microtiter plate method. For molecular analysis, genes encoding the carbapenemase enzyme (bla OXA-48, bla NDM-1, bla IMP, and bla VIM) and biofilm-related genes (treC, luxS, mrkA, and wza) were investigated by polymerase chain reaction (PCR). While 76% of clinical isolates were resistant to three or more antimicrobials, 24% were classified as non-multidrug resistant (non-MDR). When biofilm-forming capacities of clinical isolates were tested, it was determined that the resistant-isolates produced 59.2% strong biofilm, and susceptible-isolates produced 12.5% strong biofilm. According to PCR results, carbapenemase genes were determined as follows: bla OXA−48-70%, bla NDM-49%, and bla KPC-19%, bla OXA-48/bla NDM/bla KPC-12%, bla OXA-48/bla NDM-26%, and bla OXA-48/bla KPC-4%. The biofilm-associated genes in bacterial isolates were determined as follows: luxS-98%, treC-94%, mrkA-88%, and wza-15%. In addition, Hierarchical Clustering Tree and Heatmap analysis revealed an association between isolates that lacks resistance genes and isolates lacks biofilm-formation related genes that were included in MDR or non-MDR classes. As a result, biofilm should be considered in the treatment of MDR infections, and therapy should be planned accordingly. In addition, pursuing the data and genes of antibiotic resistance is significant for combating resistance.

The emergence of highly resistant and hypervirulent Klebsiella pneumoniae CC14 clone in a tertiary hospital over 8 years

BackgroundKlebsiella pneumoniae is a major bacterial and opportunistic human pathogen, increasingly recognized as a healthcare burden globally. The convergence of resistance and virulence in K. pneumoniae strains has led to the formation of hypervirulent and multidrug-resistant strains with dual risk, limiting treatment options. K. pneumoniae clones are known to emerge locally and spread globally. Therefore, an understanding of the dynamics and evolution of the emerging strains in hospitals is warranted to prevent future outbreaks.MethodsIn this study, we conducted an in-depth genomic analysis on a large-scale collection of 328 multidrug-resistant (MDR) K. pneumoniae strains recovered from 239 patients from a single major hospital in the western coastal city of Jeddah in Saudi Arabia from 2014 through 2022. We employed a broad range of phylogenetic and phylodynamic methods to understand the evolution of the predominant clones on epidemiological time scales, virulence and resistance determinants, and their dynamics. We also integrated the genomic data with detailed electronic health record (EHR) data for the patients to understand the clinical implications of the resistance and virulence of different strains.ResultsWe discovered a diverse population underlying the infections, with most strains belonging to Clonal Complex 14 (CC14) exhibiting dominance. Specifically, we observed the emergence and continuous expansion of strains belonging to the dominant ST2096 in the CC14 clade across hospital wards in recent years. These strains acquired resistance mutations against colistin and extended spectrum β-lactamase (ESBL) and carbapenemase genes, namely blaOXA-48 and blaOXA-232, located on three distinct plasmids, on epidemiological time scales. Strains of ST2096 exhibited a high virulence level with the presence of the siderophore aerobactin (iuc) locus situated on the same mosaic plasmid as the ESBL gene. Integration of ST2096 with EHR data confirmed the significant link between colonization by ST2096 and the diagnosis of sepsis and elevated in-hospital mortality (p-value < 0.05).ConclusionsOverall, these results demonstrate the clinical significance of ST2096 clones and illustrate the rapid evolution of an emerging hypervirulent and MDR K. pneumoniae in a clinical setting.

Occurrence of nosocomial multi-drug resistant Klebsiella pneumoniae in India: A systemic review and meta-analysis

Occurrence of nosocomial multi-drug resistant Klebsiella pneumoniae in India: A systemic review and meta-analysis

Rapid detection and molecular epidemiology of β-lactamase producing Enterobacteriaceae isolated from food animals and in-contact humans in Nigeria.

The emergence and spread of β-lactamase-producing Enterobacteriaceae poses a significant threat to public health, necessitating the rapid detection and investigation of the molecular epidemiology of these pathogens. We modified a multiplex real-time (RT)-PCR to concurrently detect β-lactamase genes (blaCTX-M, blaTEM, and blaSHV) and Enterobacteriaceae 16S ribosomal RNA. qPCR probes and primers were validated using control isolates, and the sensitivity and specificity assessed. The optimised multiplex qPCR was used to screen 220 non-clinical Enterobacteriaceae from food animals and in-contact humans in Southeast Nigeria selected on cefotaxime-supplemented agar plates. Binary logistic regression was used to explore factors associated with the presence of the blaTEM and blaSHV genes in these isolates, and a subset of isolates from matched sampling sites and host species were whole genome sequenced, and their antimicrobial resistance (AMR) and plasmid profiles determined. The sensitivity and specificity of the qPCR assay was 100%. All isolates (220/220) were positive for Enterobacteriaceae ribosomal 16S rRNA and blaCTX-M, while 66.4% (146/220) and 9% (20/220) were positive for blaTEM and blaSHV, respectively. The prevalence of blaTEM and blaSHV varied across different sampling sites (farm, animal market and abattoirs). Isolates from Abia state were more likely to harbour blaTEM (OR = 2.3, p = 0.04) and blaSHV (OR = 5.12,p = 0.01) than isolates from Ebonyi state; blaTEM was more likely to be detected in isolates from food animals than humans (OR = 2.34, p = 0.03), whereas the reverse was seen for blaSHV (OR = 7.23, p = 0.02). Furthermore, Klebsiella and Enterobacter isolates harboured more AMR genes than Escherichia coli, even though they were isolated from the same sample. We also identified pan resistant Klebsiella harbouring resistance to ten classes of antimicrobials and disinfectant. Therefore, we recommend ESKAPE pathogens are included in AMR surveillance in future and suggest qPCRs be utilised for rapid screening of Enterobacteriaceae from human and animal sources.