Multidrug-resistant Klebsiella Research Articles

WGS analysis of hypervirulent and MDR Klebsiella pneumoniae from Vietnam reveales an inverse relationship between resistome and virulome

The emergence of Klebsiella (K.) pneumoniae as a leading cause of nosocomial infections in Southeast Asia is of concern. Vietnam has an outstanding position with regard to antimicrobial-resistant (AMR) pathogens and is a hotspot for carbapenem-resistant K. pneumoniae. In the current study, 19 clinical K. pneumoniae strains isolated from patients in Vietnam were tested for antibiotic susceptibility, and their genome sequences were analyzed to investigate potential resistance profiles, genotypes, AMR determinants, and virulence-associated genes. More than half of the isolates were multidrug-resistant (MDR), displaying resistance to ciprofloxacin, levofloxacin, chloramphenicol, piperacillin, cefotaxime, ceftazidime, and cefepime. Carbapenem- resistance was detected in 47% (n=9) of isolates. Five isolates were assigned to sequence type (ST) 23 by multi-locus sequence typing (MLST). These ST23 strains exhibited determinants characteristic of hypervirulent strains and were sensitive to all antibiotics tested except for one strain, which was resistant to chloramphenicol and trimethoprim/sulfamethoxazole. All isolates had AMR determinants that conferred resistance to aminoglycosides and ß-lactams. Single nucleotide variants of oqxA and oqxB conferring resistance to phenicol/quinolone, ompK37 and ompA conferring resistance to beta-lactams, and lptD conferring resistance to rifamycin, were found in all isolates. Additionally, 95% of the isolates (n=18) carried fosA genes; however, only two were resistant to fosfomycin. Five isolates carried genes conferring resistance to colistin; only one carried mcr-1.1 and showed resistance to colistin. One hundred thirty virulence-associated genes were identified. The current study demonstrated an inverse relationship between the number of detected virulence determinants and antibiotic resistance. Several well-known resistance genes have been identified but did not mediate resistance, which could be due to insufficient levels or lack of expression. A comprehensive study of the genotypic findings of AMR determinants and virulence with phenotypic data is required. The presence of hypervirulent K. pneumoniae carrying specific virulomes is a growing problem, and monitoring of virulence characteristics of K. pneumoniae is important.

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

Decoding Klebsiella pneumoniae in poultry chain: unveiling genetic landscape, antibiotic resistance, and biocide tolerance in non-clinical reservoirs

The rise of antibiotic resistance in the food chain is influenced by the use of antimicrobial agents, such as antibiotics, metals, and biocides, throughout the entire farm-to-fork continuum. Besides, non-clinical reservoirs potentially contribute to the transmission of critical pathogens such as multidrug-resistant (MDR) Klebsiella pneumoniae. However, limited knowledge exists about the population structure and genomic diversity of K. pneumoniae circulating in conventional poultry production. We conducted a comprehensive characterization of K. pneumoniae across the whole chicken production chain (7 farms; 14 flocks + environment + meat, 56 samples; 2019–2022), exploring factors beyond antibiotics, like copper and quaternary ammonium compounds (QACs). Clonal diversity and adaptive features of K. pneumoniae were characterized through cultural, molecular (FT-IR), and whole-genome-sequencing (WGS) approaches. All except one flock were positive for K. pneumoniae with a significant increase (p < 0.05) from early (n = 1/14) to pre-slaughter (n = 11/14) stages, most (n = 6/7) persisting in chicken meat batches. Colistin-resistant K. pneumoniae rates were low (4%-n = 1/24 positive samples), while most samples carried MDR strains (67%-n = 16/24) and copper-tolerant isolates (63%-n = 15/24, with sil and pco gene clusters; MICCuSO4 ≥ 16 mM), particularly at pre-slaughter. Benzalkonium chloride consistently exhibited activity against K. pneumoniae (MIC/MBC range = 4–64 mg/L) from representative strains independently of the presence or absence of genes linked to QACs tolerance. A polyclonal K. pneumoniae population, discriminated by FT-IR and WGS, included various lineages dispersed throughout the chicken’s lifecycle at the farm (ST29-KL124, ST11-KL106, ST15-KL19, ST1228-KL38), until the meat (ST1-KL19, ST11-KL111, ST6405-KL109, and ST6406-CG147-KL111), or over years (ST631-49 KL109, ST6651-KL107, ST6406-CG147-KL111). Notably, some lineages were identical to those from human clinical isolates. WGS also revealed F-type multireplicon plasmids carrying sil + pco (copper) co-located with qacEΔ1 ± qacF (QACs) and antibiotic resistance genes like those disseminated in humans. In conclusion, chicken farms and their derived meat are significant reservoirs for diverse K. pneumoniae clones enriched in antibiotic resistance and metal tolerance genes, some exhibiting genetic similarities with human clinical strains. Further research is imperative to unravel the factors influencing K. pneumoniae persistence and dissemination within poultry production, contributing to improved food safety risk management. This study underscores the significance of understanding the interplay between antimicrobial control strategies and non-clinical sources to effectively address the spread of antimicrobial resistance.

Changing Landscape of Antimicrobial Resistance in Neonatal Sepsis: An in silico Analyses of Multidrug Resistance in Klebsiella pneumoniae.

Neonatal sepsis poses a critical healthcare concern, as multidrug-resistant Klebsiella pneumoniae (K. pneumoniae) infections are on the rise. Understanding the antimicrobial susceptibility patterns and underlying resistance mechanism is crucial for effective treatment. This study aimed to comprehensively investigate the antimicrobial susceptibility patterns of K. pneumoniae strains responsible for neonatal sepsis using in silico tools. We sought to identify trends and explore reasons for varying resistance levels, particularly for β-lactams and fluoroquinolone. K. pneumoniae isolated from neonates at Kanchi Kamakoti CHILDS Trust Hospital (2017-2020) were analyzed for antimicrobial resistance. Elevated resistance to β-lactam and fluoroquinolone antibiotics was further investigated through molecular docking and interaction analysis. β-lactam affinity with penicillin-binding proteins and β-lactamases was examined. Mutations in ParC and GyrA responsible for quinolone resistance were introduced to investigate ciprofloxacin interactions. Of 111 K. pneumoniae blood sepsis isolates in neonates, high resistance was detected to β-lactams such as cefixime (85.91%, n = 71), ceftriaxone (84.9%, n = 106), cefotaxime (84.9%, n = 82) and fluoroquinolone (ciprofloxacin- 79.44%, n = 107). Molecular docking revealed low β-lactam binding toward penicillin-binding proteins and higher affinities for β-lactamases, attributing to the reduced β-lactam efficiency. Additionally, ciprofloxacin showed decreased affinity toward mutant ParC and GyrA in comparison to their corresponding wild-type proteins. Our study elucidates altered resistance profiles in neonatal sepsis caused by K. pneumoniae, highlighting mechanisms of β-lactam and fluoroquinolone resistance. It underscores the urgent need for the development of sustainable therapeutic alternatives to address the rising antimicrobial resistance in neonatal sepsis.

Wedge Resection and Optimal Solutions for Invasive Pulmonary Fungal Infection and Long COVID Syndrome—A Case Report and Brief Literature Review

A rise in fungal infections has been observed worldwide among patients with extended hospital stays because of the severe infection caused by the new coronavirus pandemic. A 62-year-old female patient was admitted with a severe form of Coronavirus disease 2019 (COVID-19) and spent four weeks in the intensive care unit (ICU) requiring mechanical ventilation support before being moved to a tertiary hospital for further testing. Aspergillus fumigatus filamentous fungus, Candida spp., and positive bacteriology for multidrug-resistant Klebsiella pneumoniae and Proteus mirabilis were identified by bronchial aspirate cultures. The patient’s progress was gradually encouraging while receiving oral antifungal and broad-spectrum antibiotic therapy along with respiratory physical therapy; but ultimately, thoracic surgery was necessary. Long-lasting tissue damage and severe, persistent inflammatory syndrome were the two main pathophysiological mechanisms that led to significant outcomes regarding lung lesions that were rapidly colonized by fungi and resistant flora, cardiac damage with sinus tachycardia at the slightest effort, and chronic inflammatory syndrome, which was characterized by marked asthenia, myalgias, and exercise intolerance.

Prevalence of multidrug-resistant Klebsiella pneumoniae in urinary tract infections: A retrospective observational study in eastern India

Prevalence of multidrug-resistant Klebsiella pneumoniae in urinary tract infections: A retrospective observational study in eastern India

Prevalence of multidrug-resistant bacterial infections in diabetic foot ulcers: A meta-analysis.

Multidrug-resistant (MDR) bacterial infections have become increasingly common in recent years due to the increased prevalence of diabetic foot ulcers (DFUs). We carried out a meta-analysis aimed at investigating the prevalence of MDR bacteria isolated from DFUs and analysing the risk factors for MDR bacterial infection in patients with DFUs. The PubMed/Medline, Web of Science, Embase, Cochrane Library, Ovid, Scopus, and ProQuest databases were searched for studies published up to November 2023 on the clinical outcomes of MDR bacteria in DFUs. The main outcome was the prevalence of MDR bacteria in DFUs. A total of 21 studies were included, representing 4885 patients from which 2633 MDR bacterial isolates were obtained. The prevalence of MDR bacteria in DFUs was 50.86% (95% confidence interval (CI): 41.92%-59.78%). The prevalence of MDR gram-positive bacteria (GPB) in DFUs was 19.81% (95% CI: 14.35%-25.91%), and the prevalence of MDR gram-negative bacteria (GNB) in DFUs was 32.84% (95% CI: 26.40%-39.62%). MDR Staphylococcus aureus (12.13% (95% CI: 8.79%-15.91%)) and MDR Enterococcus spp. (3.33% (95% CI: 1.92%-5.07%)) were the main MDR-GPB in DFUs. MDR Escherichia coli, MDR Pseudomonas aeruginosa, MDR Enterobacter spp., MDR Klebsiella pneumoniae, and MDR Proteus mirabilis were the main MDR-GNB in DFUs. The prevalence rates were 6.93% (95% CI: 5.15%-8.95%), 6.01% (95% CI: 4.03%-8.33%), 3.59% (95% CI: 0.42%-9.30%), 3.50% (95% CI: 2.31%-4.91%), and 3.27% (95% CI: 1.74%-5.21%), respectively. The clinical variables of diabetic foot ulcer patients infected with MDR bacteria and non-MDR bacteria in the included studies were analysed. The results showed that peripheral vascular disease, peripheral neuropathy, nephropathy, osteomyelitis, Wagner's grade, previous hospitalization and previous use of antibacterial drugs were significantly different between the MDR bacterial group and the non-MDR bacterial group. We concluded that there is a high prevalence of MDR bacterial infections in DFUs. The prevalence of MDR-GNB was greater than that of MDR-GPB in DFUs. MDR S. aureus was the main MDR-GPB in DFUs, and MDR E. coli was the main MDR-GNB in DFUs. Our study also indicated that peripheral vascular disease, peripheral neuropathy, nephropathy, osteomyelitis, Wagner's grade, previous hospitalization, and previous use of antibacterial drugs were associated with MDR bacterial infections in patients with DFUs.

Clinically used broad-spectrum antibiotics compromise inflammatory monocyte-dependent antibacterial defense in the lung

Hospital-acquired pneumonia (HAP) is associated with high mortality and costs, and frequently caused by multidrug-resistant (MDR) bacteria. Although prior antimicrobial therapy is a major risk factor for HAP, the underlying mechanism remains incompletely understood. Here, we demonstrate that antibiotic therapy in hospitalized patients is associated with decreased diversity of the gut microbiome and depletion of short-chain fatty acid (SCFA) producers. Infection experiments with mice transplanted with patient fecal material reveal that these antibiotic-induced microbiota perturbations impair pulmonary defense against MDR Klebsiella pneumoniae. This is dependent on inflammatory monocytes (IMs), whose fatty acid receptor (FFAR)2/3-controlled and phagolysosome-dependent antibacterial activity is compromized in mice transplanted with antibiotic-associated patient microbiota. Collectively, we characterize how clinically relevant antibiotics affect antimicrobial defense in the context of human microbiota, and reveal a critical impairment of IM´s antimicrobial activity. Our study provides additional arguments for the rational use of antibiotics and offers mechanistic insights for the development of novel prophylactic strategies to protect high-risk patients from HAP.

Draft genome sequence of multidrug-resistant Klebsiella pneumoniae Hakim-RU strain isolated from a patient with urinary tract infections in Bangladesh.

We unveil the genomic sequence of the Klebsiella pneumoniae Hakim-RU strain isolated from a patient with urinary tract infections. Our assembled genome spans 4.3 Mb with 73.0× coverage, an average GC content of 57.41%, 4 plasmids, 2 CRISPR arrays, 10 prophages, 41 antibiotic resistance genes, and 6 virulence factor genes.

Assessment of Colistin Heteroresistance among Multidrug-Resistant Klebsiella pneumoniae Isolated from Intensive Care Patients in Europe.

Heteroresistance (HR) to colistin is especially concerning in settings where multi-drug-resistant (MDR) K. pneumoniae are prevalent and empiric use of colistin might lead to treatment failures. This study aimed to assess the frequency of occurrence of colistin HR (CHR) among (MDR) K. pneumoniae (n = 676) isolated from patients hospitalized in 13 intensive care units (ICUs) in six European countries in a clinical trial assessing the impact of decolonization strategies. All isolates were whole-genome-sequenced and studied for in vitro colistin susceptibility. The majority were colistin-susceptible (CS) (n = 597, MIC ≤ 2 µg/mL), and 79 were fully colistin-resistant (CR) (MIC > 2 µg/mL). A total of 288 CS isolates were randomly selected for population analysis profiling (PAP) to assess CHR prevalence. CHR was detected in 108/288 CS K. pneumoniae. No significant association was found between the occurrence of CHR and country, MIC-value, K-antigen type, and O-antigen type. Overall, 92% (617/671) of the K. pneumoniae were MDR with high prevalence among CS (91%, 539/592) and CR (98.7%, 78/79) isolates. In contrast, the proportion of carbapenemase-producing K. pneumoniae (CP-Kpn) was higher among CR (72.2%, 57/79) than CS isolates (29.3%, 174/594). The proportions of MDR and CP-Kpn were similar among CHR (MDR: 85%, 91/107; CP-Kpn: 29.9%, 32/107) and selected CS isolates (MDR: 84.7%, 244/288; CP-Kpn: 28.1%, 80/285). WGS analysis of PAP isolates showed diverse insertion elements in mgrB or even among technical replicates underscoring the stochasticity of the CHR phenotype. CHR isolates showed high sequence type (ST) diversity (Simpson's diversity index, SDI: 0.97, in 52 of the 85 STs tested). CR (SDI: 0.85) isolates were highly associated with specific STs (ST101, ST147, ST258/ST512, p ≤ 0.003). The widespread nature of CHR among MDR K. pneumoniae in our study urge the development of rapid HR detection methods to inform on the need for combination regimens.

Phenotypic and molecular characterization of multi-drug resistant Klebsiella spp. isolates recovered from clinical settings

Klebsiella pneumoniae is a Gram-negative bacterium that colonizes the gastrointestinal tract and nasopharynx with many being linked to nosocomial infections. Extended-spectrum β-lactamases (ESBL)-producing and carbapenem-resistant K. pneumoniae is recognized by the World Health Organization (WHO) as a critical public health concern. In this study, whole-genome sequencing (WGS) – based analysis was performed to understand the molecular epidemiology of multi-drug resistant Klebsiella spp. clinical isolates. Genome comparison, multi-locus sequence typing (MLST), pulsed-field gel electrophoresis (PFGE), and whole-genome-SNP-based phylogenetic analysis (wg-SNP) were used for in-depth molecular characterization. in silico typing was used to determine the resistance genes, virulence factors, Inc. groups, and capsular types. All except one isolate were non-susceptible to meropenem and 89% were non-susceptible to ertapenem and imipenem. blaNDM, blaOXA-48, and blaKPC were the detected carbapenemases with blaNDM-1 found in half of the sequenced genomes. Resistance to colistin was detected in one isolate and was linked to several genetic alterations in crrB, pmrB, and pmrC genes. The most common plasmid type was IncFIB followed by IncR, and the Type 3 fimbriae, encoded by the mrkABCDF operon, was conserved among all isolates. The most common sequence- (ST) and K-type detected were ST147 and K64. The prevelance and the genomic relatedness of ST147 isolates, as shown by the data from SNP-based phylogenetic analysis, PFGE, and genomic clustering, may be an outbreak marker. However, this can only be validated through a more comprehensive study encompassing a wider sampling scheme and over an extended timeframe.

Supernatant of platelet-Klebsiella pneumoniae coculture induces apoptosis-like death in Klebsiella pneumoniae.

Multidrug-resistant Klebsiella pneumoniae strains, especially carbapenem-resistant K. pneumoniae, have become a rapidly emerging crisis worldwide, greatly limiting current therapeutic options and posing new challenges to infection management. Therefore, it is imperative to develop novel and effective biological agents for the treatment of multidrug-resistant K. pneumoniae infections. Platelets play an important role in the development of inflammation and immune responses. The main component responsible for platelet antibacterial activity lies in the supernatant stimulated by gram-positive bacteria. However, little research has been conducted on the interaction of gram-negative bacteria with platelets. Therefore, we aimed to explore the bacteriostatic effect of the supernatant derived from platelet-K. pneumoniae coculture and the mechanism underlying this effect to further assess the potential of platelet-bacterial coculture supernatant. We conducted this study on the gram-negative bacteria K. pneumoniae and CRKP and detected turbidity changes in K. pneumoniae and CRKP cultures when grown with platelet-K. pneumoniae coculture supernatant added to the culture medium. We found that platelet-K. pneumoniae coculture supernatant significantly inhibited the growth of K. pneumoniae and CRKP in vitro. Furthermore, transfusion of platelet-K. pneumoniae coculture supernatant alleviated the symptoms of K. pneumoniae and CRKP infection in a murine model. Additionally, we observed apoptosis-like changes, such as phosphatidylserine exposure, chromosome condensation, DNA fragmentation, and overproduction of reactive oxygen species in K. pneumoniae following treatment with the supernatant. Our study demonstrates that the platelet-K. pneumoniae coculture supernatant can inhibit K. pneumoniae growth by inducing an apoptosis-like death, which is important for the antibacterial strategies development in the future.IMPORTANCEWith the widespread use of antibiotics, bacterial resistance is increasing, and a variety of multi-drug resistant Gram-negative bacteria have emerged, which brings great challenges to the treatment of infections caused by Gram-negative bacteria. Therefore, finding new strategies to inhibit Gram-negative bacteria and even multi-drug- resistant Gram-negative bacteria is crucial for treating infections caused by Gram-negative bacteria, improving the abuse of antibiotics, and maintaining the balance between bacteria and antibiotics. K. pneumoniae is a common clinical pathogen, and drug-resistant CRKP is increasingly difficult to cure, which brings great clinical challenges. In this study, we found that the platelet-K. pneumoniae coculture supernatant can inhibit K. pneumoniae growth by inducing an apoptosis-like death. This finding has inspired the development of future antimicrobial strategies, which are expected to improve the clinical treatment of Gram-negative bacteria and control the development of multidrug-resistant strains.

Spread and evolution of blaKPC-plasmid between Serratia marcescens and Klebsiella pneumoniae

The emergence and prevalence of carbapenem-resistant Enterobacterales on a global scale has posed a serious challenge to global public health security. Clinical research has rarely reported the co-infection of multidrug-resistant Serratia marcescens and Klebsiella pneumoniae. In this study, we describe the case of a hospitalized patient infected with carbapenem-resistant S. marcescens and K. pneumoniae. The evolution and transmission of blaKPC-2 occurred during the treatment with ceftazidime-avibactam and trimethoprim-sulfamethoxazole. Analysis of the antimicrobial susceptibility and genetic profiles of the clinical strains showed that blaKPC-2 evolved into blaKPC-71 and blaKPC-44, together with resistance to ceftazidime-avibactam and carbapenems susceptibility recovery under antimicrobial pressure. Cloning and expression of blaKPC-44 & blaKPC-71 in E. coli DH5α showed that KPC-44 and KPC-71 resulted in a 64∼128-fold increase in the MIC value for ceftazidime-avibactam. Meanwhile, the kinetic assays also showed that the enzyme activity of KPC-44 and KPC-71 towards carbapenems was destroyed and couldn't be inhibited by avibactam. Based on the conjugation assay and whole genome sequence analyses, we provided evolutionary insights into the transmission pathway trace of blaKPC-bearing plasmids between S. marcescens and K. pneumoniae. Based on the sharp decrease in conjugation frequency and the loss of blaKPC-bearing plasmids during treatment, we predicted that the evolution of blaKPC has affected the efficiency and stability of plasmid transmission between species. Mixed-species co-infection is one of the risk factors leading to the spread of plasmids carrying carbapenem-resistant genes, and increased surveillance of multidrug-resistant Enterobacterales is urgently needed.

Tigecycline is the Most Effective against Multi-Drug Resistant Klebsiella pneumoniae Recovered from Burn Wound Infections in Two Hospitals in Al-Kut City, Iraq

     Klebsiella pneumoniae is among the most frequent microorganisms isolated from infections of burn wounds. This cross-sectional study aimed to investigate the distribution of multi-drug resistant (MDR) K. pneumoniae in two burn hospitals and the antibiotic resistance profile in different burn regions of the same patient. It was performed in two hospitals (Al-Zahraa and Al-Karama) in Al-Kut, Iraq, between January and May 2022. Totally, 100 burn swabs were collected from 40 patients of both genders suffering from burn wound infections, with ages ranging between 3 and 50 years. Klebsiella pneumoniae were isolated and identified using conventional methods followed by VITEK®2 system and confirmed via polymerase chain reaction targeting the gapA gene. Then, the antimicrobial susceptibility pattern was studied by the VITEK®2 system. Of the 100 burn wound swabs, 20 isolates were K. pneumoniae. Fifty five percent (11 out of 20) of K. pneumoniae isolated in the current study were MDR and 35% of the isolates had the extended spectrum beta-lactamase (ESBL) which is the main antibiotic resistance mechanism. Furthermore, the bacteria isolated from different burned areas of the same patient showed variable pattern of antibiotic susceptibility. To conclude, K. pneumoniae contaminating the burn wards in the Iraqi hospitals are mostly MDR, against which tigecycline is the most effective antibiotic.

Molecular epidemiology of multidrug-resistant Klebsiella pneumoniae, Enterobacter cloacae, and Escherichia coli outbreak among neonates in Tembisa hospital, South Africa.

An outbreak of multidrug-resistant Klebsiella pneumoniae, Escherichia coli, and Enterobacter cloacae infections in a neonatal ward within a tertiary hospital in South Africa resulted in the mortality of 10 patients within six months. In this work, the genomic epidemiology of and the molecular factors mediating this outbreak were investigated. Bacterial cultures obtained from clinical samples collected from the infected neonates underwent phenotypic and molecular analyses to determine their species, sensitivity to antibiotics, production of carbapenemases, complete resistance genes profile, clonality, epidemiology, and evolutionary relationships. Mobile genetic elements flanking the resistance genes and facilitating their spread were also characterized. The outbreak was centered in two major wards and affected mainly neonates between September 2019 and March 2020. Most isolates (n = 27 isolates) were K. pneumoniae while both E. coli and E. cloacae had three isolates each. Notably, 33/34 isolates were multidrug resistant (MDR), with 30 being resistant to at least four drug classes. All the isolates were carbapenemase-positive, but four bla OXA-48 isolates were susceptible to carbapenems. Bla NDM-1 (n = 13) and bla OXA-48/181 (n = 15) were respectively found on IS91 and IS6-like IS26 composite transposons in the isolates alongside several other resistance genes. The repertoire of resistance and virulence genes, insertion sequences, and plasmid replicon types in the strains explains their virulence, resistance, and quick dissemination among the neonates. The outbreak of fatal MDR infections in the neonatal wards were mediated by clonal (vertical) and horizontal (plasmid-mediated) spread of resistant and virulent strains (and genes) that have been also circulating locally and globally.

Analysis of Blood Cultures from Major Burns Patients in a Tertiary Care Burn Unit in Oman.

This study aimed to review the blood stream infections of major burn patients in a tertiary care burn unit to determine the most prevalent infecting organisms in order to have a better empirical therapy protocol. This retrospective study analysed the blood stream infection of 155 major burn (>20% Total Body Surface Area [TBSA]) patients in Khoula Hospital, Muscat, Oman between January 2014 to December 2019. The median age was 33 years and 57.42% of patients were male. The median TBSA was 38%, mortality was 25.16% and 50.9% of patients had positive blood cultures. The expired patients had higher TBSAs, Abbreviated Burns Severity Index scores and earlier first positive blood cultures. Candida was commonly grown in all the blood cultures, but the most prevalent organisms were Acinetobacter, Staphylococci, Klebsiella, Enterococcus and Pseudomonas. All Acinetobacter species are multidrug resistant. Of the 17 patients who had Kelbsiella grown in the blood culture, 8 grew multidrug-resistant Klebsiella. Only 4 patients' blood cultures grew methicillin-resistant Staphylococcus aureus. The number of blood culture samples taken ranged between 1-28 (median = 6). The first positive blood culture showed that Staphylococcus epidermidis and Acinetobacter were the most common infecting organisms. Multidrug-resistant Acinetobacter was the most predominant microorganism grown from the blood cultures of major burn patients in a tertiary care burn unit. Empirical therapy should include antibiotics that are effective against this organism to reduce the mortality.

Use of a combined antibacterial synergy approach and the ANNOgesic tool to identify novel targets within the gene networks of multidrug-resistant Klebsiella pneumoniae.

Since the 1980s, the development of new drug classes for the treatment of multidrug-resistant Klebsiella pneumoniae has become limited, highlighting the urgent need for novel antibiotics. To address this challenge, this study aimed to explore the synergistic interactions between chemical compounds and representative antibiotics, such as carbapenem and colistin. The primary objective of this study was not only to mitigate the adverse impact of multidrug-resistant K. pneumoniae on public health but also to establish a sustainable balance among humans, animals, and the environment. Phenotypical measurements were conducted using the broth microdilution technique to determine the drug sensitivity of bacterial strains. Additionally, a genotypical approach was employed, involving traditional RNA sequencing analysis to identify differentially expressed genes and the computational ANNOgesic tool to detect noncoding RNAs. This study revealed the existence of various pathways and regulatory RNA elements that form a functional network. These pathways, characterized by the expression of specific genes, contribute to the combined treatment effect and bacterial survival strategies. The connections between pathways are facilitated by regulatory RNA elements that respond to environmental changes. These findings suggest an adaptive response of bacteria to harsh environmental conditions.IMPORTANCENoncoding RNAs were identified as key players in post-transcriptional regulation. Moreover, this study predicted the presence of novel small regulatory RNAs that interact with target genes, as well as the involvement of riboswitches and RNA thermometers in conjunction with associated genes. These findings will contribute to the discovery of potential antimicrobial therapeutic candidates. Overall, this study offers valuable insights into the synergistic effects of chemical compounds and antibiotics, highlighting the role of regulatory RNA elements in bacterial response, and survival strategies. The identification of novel noncoding RNAs and their interactions with target genes, riboswitches, and RNA thermometers holds promise for the development of antimicrobial therapies.

ST218 Klebsiella pneumoniae became a high-risk clone for multidrug resistance and hypervirulence

BackgroundThe occurrence of multidrug-resistant and hypervirulent Klebsiella pneumoniae (MDR-hvKp) worldwide poses a great challenge for public health. Few studies have focused on ST218 MDR-hvKp.MethodsRetrospective genomic surveillance was conducted at the Peking University Third Hospital from 2017 and clinical information was obtained. To understand genomic and microbiological characteristics, antimicrobial susceptibility testing, plasmid conjugation and stability, biofilm formation, serum killing, growth curves and whole-genome sequencing were performed. We also assessed the clinical and microbiological characteristics of ST218 compared with ST23.ResultsA total of eleven ST218 Kp isolates were included. The most common infection type was lower respiratory tract infection (72.7%, 8/11) in our hospital, whereas ST23 hvKp (72.7%, 8/11) was closely associated with bloodstream infection. Notably, nosocomial infections caused by ST218 (54.5%, 6/11) was slightly higher than ST23 (36.4%, 4/11). All of the ST218 and ST23 strains presented with the virulence genes combination of iucA + iroB + peg344 + rmpA + rmpA2. Interestingly, the virulence score of ST218 was lower than ST23, whereas one ST218 strain (pPEKP3107) exhibited resistance to carbapenems, cephalosporins, β-lactamase/inhibitors and quinolones and harbored an ~ 59-kb IncN type MDR plasmid carrying resistance genes including blaNDM-1, dfrA14 and qnrS1. Importantly, blaNDM-1 and qnrS1 were flanked with IS26 located within the plasmid that could successfully transfer into E. coli J53. Additionally, PEKP2044 harbored an ~ 41-kb resistance plasmid located within tetA indicating resistance to doxycycline.ConclusionThe emergence of blaNDM-1 revealed that there is great potential for ST218 Kp to become a high-risk clone for MDR-hvKp, indicating the urgent need for enhanced genomic surveillance.

Prevalence of phenotypic multi-drug resistant Klebsiella species recovered from different human specimens in Ethiopia: A systematic review and meta-analysis.

Multidrug-resistant (MDR) Klebsiella species are among public health important bacteria that cause infections difficult to treat with available antimicrobial agents. Infections with Klebsiella lead to high morbidity and mortality in developing countries particularly in patients admitted to the intensive care unit. This systematic review and meta-analysis aimed to determine the pooled prevalence of MDR Klebsiella species from different human specimens using studies conducted in Ethiopia from 2018-2022. We have systematically searched online databases such as PubMed/Medline, Google Scholar, Hinari, African journals online, Web of Science, Cochrane, and grey literature (Addis Ababa University and Hawassa University) to identify studies reporting the proportion of MDR Klebsiella species in Ethiopia. Published articles were selected based on the Preferred Reporting Item of Systematic Review and Meta-analysis (PRISMA). R-Studio version 4.2.3 was used to conduct pooled prevalence, heterogeneity test, and publication bias. A binary random effect model was used to determine the pooled prevalence. Heterogeneity was checked with the inconsistency index (I2). Publication bias was checked with a funnel plot and Egger test. Sensitivity analysis was conducted with leave-one-out analysis. Joanna Briggs Institute's critical appraisal tool for prevalence studies was used to check the quality of each article. In this systematic review and meta-analysis, 40 articles were included in which 12,239 human specimens were examined. Out of the total specimens examined, 721 Klebsiella species were isolated and 545 isolates were reported to be MDR Klebsiella species. The prevalence of MDR Klebsiella species ranged from 7.3%-100% whereas the pooled prevalence of MDR Klebsiella species was 72% (95% CI: 63 - 82%, I2 = 95%). Sub-group analysis based on region revealed the highest prevalence of MDR from Addis Ababa (97%) and the least from the Somali region (33%); whereas sub-group analysis based on the specimen type indicated the highest prevalence was from blood culture specimens 96% and the least was from other specimens (ear and vaginal discharge, and stool) (51%). Our finding indicated a high prevalence of MDR Klebsiella species found in different human specimens. The prevalence of MDR Klebsiella varies across regions in Ethiopia, age, the type of specimens, source and site of infection. Therefore, integrated action should be taken to reduce the prevalence of MDR Klebsiella species in regional states and focus on clinical features. Effective infection and prevention control should be applied to reduce the transmission within and outside health care settings.

Klebsiella pneumoniae ST147 harboring blaNDM-1, multidrug resistance and hypervirulence plasmids.

The spread of hypervirulent (hv) and carbapenem-/multidrug-resistant Klebsiella pneumoniae is an emerging problem in healthcare settings. The New Delhi metallo-β-lactamase-1 (blaNDM-1) is found in Enterobacteriaceae including K. pneumoniae. The blaNDM-1 is capable of hydrolyzing β-lactam antibiotics which are used for treatment of severe infections caused by multidrug-resistant Gram-negative bacteria. This is associated with the unacceptably high mortality rate in immunocompromised burn injury patients. This study reports on the characterization of blaNDM-1 gene and virulence factors in hv carbapenem-/multidrug-resistant K. pneumoniae ST147 in the burns unit of a tertiary teaching hospital during routine surveillance. Two K. pneumoniae strains were obtained from wounds of burn-infected patients from May 2020 to July 2021. The hypervirulence genes and genetic context of the blaNDM-1 gene and mobile genetic elements potentially involved in the transposition of the gene were analyzed. We identified a conserved genetic background and an IS26 and open reading frame flanking the blaNDM-1 gene that could suggest its involvement in the mobilization of the gene. The plasmid harbored additional antibiotic resistance predicted regions that were responsible for resistance to almost all the routinely used antibiotics. To ensure the identification of potential outbreak strains during routine surveillance, investigations on resistance genes and their environment in relation to evolution are necessary for molecular epidemiology.IMPORTANCEData obtained from this study will aid in the prompt identification of disease outbreaks including evolving resistance and virulence of the outbreak bacteria. This will help establish and implement antimicrobial stewardship programs and infection prevention protocols in fragile health systems in countries with limited resources. Integration of molecular surveillance and translation of whole-genome sequencing in routine diagnosis will provide valuable data for control of infection. This study reports for the first time a high-risk clone K. pneumoniae ST147 with hypervirulence and multidrug-resistance features in Ghana.