Multidrug-resistant Klebsiella Pneumoniae Research Articles

Pathogenomics analysis of high-risk clone ST147 multidrug-resistant Klebsiella pneumoniae isolated from a patient in Egypt

BackgroundThe emergence of multi-drug-resistant Klebsiella pneumoniae (MDR-KP) represents a serious clinical health concern. Antibiotic resistance and virulence interactions play a significant role in the pathogenesis of K. pneumoniae infections. Therefore, tracking the clinical resistome and virulome through monitoring antibiotic resistance genes (ARG) and virulence factors in the bacterial genome using computational analysis tools is critical for predicting the next epidemic.MethodsIn the current study, one hundred extended spectrum β-lactamase (ESBL)-producing clinical isolates were collected from Mansoura University Hospital, Egypt, in a six-month period from January to June 2022. One isolate was selected due to the high resistance phenotype, and the genetic features of MDR-KP recovered from hospitalized patient were investigated. Otherwise, the susceptibility to 25 antimicrobials was determined using the DL Antimicrobial Susceptibility Testing (AST) system. Whole genome sequencing (WGS) using Illumina NovaSeq 6000 was employed to provide genomic insights into K. pneumoniae WSF99 clinical isolate.ResultsThe isolate K. pneumoniae WSF99 was phenotypically resistant to the antibiotics under investigation via antibiotic susceptibility testing. WGS analysis revealed that WSF99 total genome length was 5.7 Mb with an estimated 5,718 protein-coding genes and a G + C content of 56.98 mol%. Additionally, the allelic profile of the WSF99 isolate was allocated to the high-risk clone ST147. Furthermore, diverse antibiotic resistance genes were determined in the genome that explain the high-level resistance phenotypes. Several β-lactamase genes, including blaCTX−M−15, blaTEM−1, blaTEM−12, blaSHV−11, blaSHV−67, and blaOXA−9, were detected in the WSF99 isolate. Moreover, a single carbapenemase gene, blaNDM−5, was predicted in the genome, positioned within a mobile cassette. In addition, other resistance genes were predicted in the genome including, aac(6’)-Ib, aph(3’)-VI, sul1, sul2, fosA, aadA, arr-2, qnrS1, tetA and tetC. Four plasmid replicons CoIRNAI, IncFIB(K), IncFIB(pQil), and IncR were predicted in the genome. The draft genome analysis revealed the occurrence of genetic mobile elements positioned around the ARGs, suggesting the ease of dissemination via horizontal gene transfer.ConclusionsThis study reports a comprehensive pathogenomic analysis of MDR-KP isolated from a hospitalized patient. These findings could be relevant for future studies investigating the diversity of antimicrobial resistance and virulence in Egypt.

Tigecycline as Salvage Therapy in a Neonate with Multidrug-resistant Klebsiella pneumoniae Meningitis and Ventriculitis – Case Report and Literature Review

Multi drug resistant (MDR) infections especially in paediatric population, with already limited treatment options, often leave clinicians at loss for an effective antimicrobial treatment making us as helpless as in pre-antibiotic era. Tigecycline is an ‘immature’ antibiotic for children. According to FDA, tigecycline is only indicated in patients 18 years of age and older for the treatment of complicated MDR infection. According to the published literature, the youngest patient on whom Tigecycline treatment has been attempted was 73 day old baby born at 27 weeks gestation with a birth weight of 1028 grams having Acinetobacter baumanii ventriculitis . Here, we discuss use of Tigecycline in a neonate with MDR Klebsiella Pneumoniae meningitis and ventriculitis who presented to us on day 12 of life. Child was born preterm at 34 weeks and 3 days by Lower Segment Caesarean Section in view of foetal distress, maternal preeclampsia and gestational hypothyroidism in a private hospital. On 12thday of life the baby presented to our hospital after being referred with complaints of abnormal body movements, lethargy, difficulty in taking feeds and difficulty in breathing. The complaints had been documented to be present since birth but were increasing over time. Aerobic culture of CSF led to isolation of multi-drug resistant (MDR) Klebsiella pneumoniae resistant to most empirical antibiotics, with intermediate susceptibility to Amikacin susceptibility to Colistin and Tigecycline. We found our isolate produced both NDM and OXA-48 contributing to the increased virulence and resistance of the strain. Considering the paucity of knowledge of Tigecycline’s efficacy and safety in children less than 8 years, lack of FDA approval and the fact that CSF bioavailability is considered low, Tigecycline therapy was deferred and infant was continued on injection Meropenem and injection Amikacin. Condition of child did not improve and marginal weight gain was documented over next 10 days. CSF culture from repeat LP again grew Klebsiella pneumoniae with same susceptibility pattern. On day 23 due adverse affects, and injection Tigecycline was added. A total of 42 days of Meropenem and 21 days of Tigecycline were completed and child was discharged after 42 days of hospital stay. Child was gaining weight, taking feeds orally and no abnormal body movements were present. The child is being followed up for long term sequelae of HIE 2 and meningitis on OPD basis

Enhancing bactericidal activities of ciprofloxacin by targeting the trans-translation system that is involved in stress responses in Klebsiella pneumoniae.

Although the trans-translation system is a promising target for antcibiotic development, its antibacterial mechanism in Klebsiella pneumoniae (KP) is unclear. Considering that tmRNA was the core component of trans-translation, this study firstly investigated phenotypic changes caused by various environmental stresses in KP lacking trans-translation activities (tmRNA-deleted), and then aimed to evaluate antibacterial activities of the trans-translation-targeting antibiotic combination (tobramycin/ciprofloxacin) in clinical KP isolates based on inhibition activities of aminoglycosides against trans-translation. We found that the tmRNA-deleted strain P4325/ΔssrA was significantly more susceptible than the wild-type KP strain P4325 under environments with hypertonicity (0.5 and 1M NaCl), hydrogen peroxide (40mM), and UV irradiation. No significant differences in biofilm formation and survivals under human serum were observed between P4325/ΔssrA and P4325. tmRNA deletion caused twofold lower MIC values for aminoglycosides. As for the membrane permeability, tmRNA deletion increased ethidium bromide (EtBr) uptake of KP in the presence or absence of verapamil and carbonyl cyanide-m-chlorophenylhydrazone (CCCP), decreased EtBr uptake in presence of reserpine in P4325/ΔssrA, and reduced EtBr efflux in P4325/ΔssrA in the presence of CCCP. The time-kill curve and in vitro experiments revealed significant bactericidal activities of the tmRNA-targeting aminoglycoside-based antibiotic combination (tobramycin/ciprofloxacin). Thus, the corresponding tmRNA-targeting antibiotic combinations (aminoglycoside-based) might be effective and promising treatment options against multi-drug resistant KP.

Synergistic action of 6-gingerol as an adjuvant to colistin for susceptibility enhancement in multidrug-resistant Klebsiella pneumoniae isolates.

The growing threat to human health posed by multidrug-resistant Klebsiella pneumoniae (MDR-KP) indicates an urgent need to develop alternative therapeutic options. The emergence of colistin resistance further adds to the complexity. The study aims to explore in silico-screened phytomolecule 6-gingerol, the most potent active constituent of ginger, as an adjuvant to restore sensitivity in MDR-KP isolates to colistin. The screening of phytocompounds of Zingiber officinale were obtained from the spiceRx database, and molecular docking with efflux pump protein AcrB was performed using Schrödinger's Glide program. The synergistic and bactericidal effects of 6-gingerol in combination with colistin against MDR-KP isolates were determined following broth micro-dilution (MIC), checkerboard assay, and time-kill study. 6-Gingerol showed a good binding affinity with AcrB protein (-9.32 kcal mol-1) and followed the Lipinski rule of (RO5), demonstrating favourable drug-like properties. Further, the synergistic interaction of 6-gingerol with colistin observed from checkerboard assays against efflux-mediated colistin resistance MDR-KP isolates reveals it to be a prospectus adjuvant. The time-killing assays showed the effect of 6-gingerol in combination with colistin to be bactericidal against MSK9 and bacteriostatic against MSK4 and MSK7. Overall, the study provides insights into the potential use of 6-gingerol as a safe and easily available natural product to treat multidrug-resistant K. pneumoniae infections combined with colistin but needs in vivo toxicity evaluation before further recommendations can be made.

Clinical efficacy and safety of tigecycline based on therapeutic drug monitoring for carbapenem-resistant Gram-negative bacterium pneumonia in intensive care units

BackgroundWe investigated the associations between the different doses of tigecycline, its efficacy and safety, and the role of tigecycline therapeutic drug monitoring for patients in the intensive care unit.MethodsThis study was a single-center cohort including patients infected with multidrug-resistant Acinetobacter baumannii (MDR-AB) and multidrug-resistant Klebsiella pneumoniae (MDR-KP) causing pulmonary infections. The steady-state plasma concentration after tigecycline administration was determined by High-Performance Liquid Chromatography (HPLC) in patients admitted to the ICU between October 2020 and December 2021. Multivariate analyses of tigecycline’s clinical efficacy and safety were performed to control confounding factors.ResultsFor this study, we included 45 patients and 45 blood samples to determine steady-state trough concentrations of tigecycline. All patients were divided into the High Dose (HD) and Standard Dose (SD) groups. The median trough concentration of tigecycline was 0.56 μg/mL in the HD group, which was higher than in the SD group (0,21 μg/mL), p = 0.000. There was no significant difference between the two groups of patients in terms of bacterial eradication rate, mortality rate, and clinical efficacy. Multiple regression analysis showed that the ICU days were correlated with mortality OR 1.030(1.005–1.056), p = 0.017. APACHE II was significantly associated with clinical efficacy OR 0.870(0.755–1.002), p = 0.045. The level of fibrinogen decline in the HD group was significantly higher than in the SD group (-3.05 ± 1.67 vs -1.75 ± 1.90), p = 0.038. We identified that age and tigecycline treatment duration influenced fibrinogen decline.ConclusionsTigecycline plasma concentrations are significantly increased when using a high dose. However, the plasma concentration of tigecycline is not correlated with clinical efficacy and adverse reactions. Fibrinogen decline appears to be related to the patient’s age and days of tigecycline. Large sample data are still needed to confirm the clinical guidance significance of tigecycline TDM.

Revealing active constituents within traditional Chinese Medicine used for treating bacterial pneumonia, with emphasis on the mechanism of baicalein against multi-drug resistant Klebsiella pneumoniae

Ethnopharmacological relevanceThe emergence of antibiotic-resistant bacteria has rendered it more challenging to treat bacterial pneumonia. Traditional Chinese medicine (TCM) has superior efficacy in the treatment of pneumonia, and it has the unique advantage of antibacterial resistance against multi-drug resistant (MDR) bacteria, but the medication rule and pharmacological mechanism of its antibacterial activity are not clear. Aim of the studyThis study aims to reveal Chinese medication patterns in treating bacterial pneumonia to select bioactive constituents in core herbs, predict their pharmacological mechanisms and further explore their antibacterial ability against clinically isolated MDR Klebsiella pneumoniae (KP) and their antibacterial mechanisms. Materials and methodsThe high-frequency medicinal herbs to treat lung diseases were first screened from Pharmacopoeia of the People's Republic of China (ChP.), and then bioactive compounds in core herbs and targets for compounds and disease were collected. Potential targets, signaling pathways, and drugs' core components were determined by constructing protein-protein interaction network, enrichment analysis and "component-target-pathway-disease" network were mapped by Cytoscape 3.8.2, and the potential therapeutic value of selected core components was verified by comparing the disease targets in the GEO database with the herbal component targets in the ITCM database. The clinically isolated KP were screened by drug sensitivity tests with meropenem (MEM), polymyxin E (PE), and tigecycline and biofilm-forming assay; broth microdilution, chessboard methods and biofilm morphology and permeability experiments were employed to determine the antibacterial, bactericidal and biofilm inhibition ability of selected bioactive constituents alone and in combination with antibiotics; The mechanism of bioactive components on quorum sensing (QS) genes LuxS and LuxR was predicted by molecular docking and tested by RT-PCR. ResultsThe 13 core Chinese medicines were obtained by mining ChP., and 615 potential targets of core herbal medicine were screened, and the PI3K-Akt signaling pathway might play crucial roles in the therapeutic process. In-vitro experiments revealed that the selected core compounds, including forsythoside B, baicalin, baicalein, and forsythin, all have antibacterial activity, in which baicalein had the strongest ability and a synergistic effect in combination with MEM or PE. Their synergy exhibited a stronger effect on biofilms of MDR KP, inhibiting biofilm formation, disrupting formed biofilms, and removing the residual structures of dead bacteria. Baicalein was predicted to have stable binding capacity to LuxS and LuxR genes by molecular docking, and RT-PCR results verified that the combination of baicalein with MEM or PE was effective in inhibiting the expression of QS genes (LuxS and LuxR) and consequently suppressing biofilm formation. ConclusionThe core Chinese herbal medicine in the ChP. to treat lung diseases has a multi-component, multi-target, and multi-pathway synergy to improve bacterial pneumonia. Experimental studies have confirmed that the bioactive compound baicalein was able to combat MDR KP alone and synergistic with MEM or PE, inhibited and disrupted biofilms via regulating LuxS and LuxR genes, and further disturbed quorum sensing system to promote the therapeutic efficacy, which provides a new pathway and rationale for treating MDR KP-induced bacterial pneumonia.

In Vitro antibiotic combinations of Colistin, Meropenem, Amikacin, and Amoxicillin/clavulanate against multidrug-resistant Klebsiella pneumonia isolated from patients with ventilator-associated pneumonia

BackgroundHospital infections such as ventilator-associated pneumonia (VAP) due to multidrug-resistant Klebsiella pneumoniae (MDR-KP) strains have increased worldwide. In addition, biofilm production by these resistant isolates has confronted clinicians with higher treatment failure and infection recurrence. Given the paucity of new agents and limited data on combination therapy for MDR-KPs, the present study sought to evaluate the in vitro activity of several antibiotic combinations against planktonic and biofilm MDR-KPs isolated from patients with VAP.ResultsAll 10 carbapenem-resistant Klebsiella pneumoniae (CRKP) isolates demonstrated multidrug resistance against the tested antibiotics. At planktonic mode, combinations of colistin-meropenem and amoxicillin/clavulanate in combination with meropenem, colistin, or amikacin showed synergism against 60–70% isolates. On the other hand, in the biofilm state, colistin-based combinations exhibited synergism against 50–70% isolates and the most effective combination was colistin-amikacin with 70% synergy.ConclusionsThe results revealed that combinations of amoxicillin/clavulanate with colistin, meropenem, or amikacin in the planktonic mode and colistin with amoxicillin/clavulanate, meropenem, or amikacin in the biofilm mode could effectively inhibit CRKP isolates, and thus could be further explored for the treatment of CRKPs.

Multidrug-resistant Klebsiella Pneumoniae Infection Led to Resection of the Graft in a Small Bowel Transplant Recipient: A Case Report and Review of the Literature

Infection due to multidrug-resistant Klebsiella pneumoniae is a common cause of graft resection after small bowel transplantation. We report a failed case in which the intestinal graft was resected 18 days after the operation due to postoperative infection with multidrug-resistant K pneumoniae and a literature review of other common causes of small bowel transplantation failure have been reported. A female, 29 years of age, underwent partial living small bowel transplantation for short bowel syndrome. After the operation, the patient was infected with multidrug-resistant K pneumoniae, even though various anti-infective regimens were employed. It further developed into sepsis and disseminated into intravascular coagulation, leading to exfoliation and necrosis of the intestinal mucosa. Finally, the intestinal graft had to be resected to save the patient's life. Multidrug-resistant K pneumoniae infection often affects the biological function of intestinal grafts and can even lead to necrosis. Other common causes of failure, including postoperative infection, rejection, post-transplantation lymphoproliferative disorder, graft-vs-host disease, surgical complications, and other related diseases, were also discussed throughout the literature review. Pathogenesis due to diverse and interrelated factors makes the survival of intestinal allografts a great challenge. Therefore, only by fully understanding and mastering the common causes of surgical failure can the success rate of small bowel transplantation be effectively improved.

A Study on IFN-γ and IL-10 Gene Expression Changes in Gallus Gallus Domesticus Embryo Infected with Klebsiella Pneumoniae and its Possible Alteration by Bakreshwar Hot Spring Water

Background: Hot spring's water is enriched with minerals which has many therapeutic values. Bakreshwar is well known for its ten hot springs of varying temperatures (35°C-71°C). Bathing repeatedly in hot springs can help us to fight against skin infection, rheumatic disorders, joint pain etc. Objectives: The present study aimed to explore the changes in the gene expression of IL-10 and IFN-γ in the Gallus gallus domesticus embryo, infected with multi-drug-resistant Klebsiella pneumoniae and by using the Bakreshwar hot spring water to make any curative changes in the target gene expression or not. Methodology: 14 days old embryonated eggs of Gallus gallus domesticus was inoculated with freshly prepared 0.5 Mc Farland standard suspension of Klebsiella pneumoniae and curative set was treated with Bakreshwar Hot Spring water, collected from Agnikund (65°C). Then the embryonated eggs were harvested following the Institutional Ethical Committee guidelines and the allantoic fluid was collected. On the next day, RNA extraction was performed and cDNA synthesis followed by RT PCR was performed to study the cytokine gene expression. Results: After infection of chick embryo Gallus gallus domesticus with multi drug resistant Klebsiella pneumoniae, both IL-10 and IFN-γ gene expression was increased, but in curative sets that were challenged with Bakreshwar water, IL-10 gene expression was decreased and IFN-γ was increased. Conclusion: Hot spring water of Bakreshwar has antimicrobial effect on multi drug resistant Klebsiella pneumonia and it can normalize the cytokine balance with prolonged protection with raised IFN-γ.

Changing Trend in the Antibiotic Resistance Pattern of Klebsiella Pneumonia Isolated From Endotracheal Aspirate Samples of ICU Patients of a Tertiary Care Hospital in North India.

Introduction Klebsiella pneumonia is one of the most prevalent bacteria that cause nosocomial infections, particularly in critically ill patients in the intensive care unit (ICU). Multi-drug-resistant Klebsiella pneumoniae (MDRKP) has become an urgent risk to public health as its prevalence has sharply surged around the globe in recent decades. Therefore, this research was conducted to evaluate shifts over a four-year period in drug susceptibility patterns among Klebsiella pneumoniae isolates from mechanically ventilated intensive care unit patients. Materials and methods This is a retrospective observational study conducted in a tertiary care multi-specialty hospital and teaching institute in North India and was approved by the institutional ethics committee. The research comprised Klebsiella pneumoniae isolates from endotracheal aspirates (ETA) of patients on mechanical ventilation admitted to the general intensive care unit (ICU) of our tertiary care facility. The data from January to June 2018 and January to June 2022 were collected. According to the antimicrobial resistance profile of the strains, they were categorized as susceptible, resistant to one or two antimicrobial categories, multidrug-resistant (MDR), extensively drug-resistant (XDR), or pan-drug-resistant (PDR). The criteria for MDR, XDR, and PDR were proposed by the European Centre for Disease Prevention and Control (ECDC). IBM Statistical Package for the Social Sciences (SPSS) for Windows, Version 24.0, Armonk, NY, IBM Corp., was used for data input and analysis. Results A total of 82 cases of Klebsiella pneumonia were included in the study. Of these 82 isolates, 40 were isolated over a period of six months from January to June 2018, and the remaining 42 were isolated from January to June 2022. Among the 2018 group, five strains (12.5%) were classified as susceptible, three (7.5%) as resistant, seven (17.5%) as MDR, and 25 (62.5%) as XDR. The highest percentages of antimicrobial resistance in the 2018 group were observed with amoxicillin/clavulanic acid (90%), ciprofloxacin (100%), piperacillin/tazobactam (92.5%), and cefoperazone/sulbactam (95%). In comparison, the 2022 group showed no strain as susceptible; nine strains (21.4%) were classified as resistant; three strains (7%) as MDR; and 30 strains (93%) were classified as XDR. There was a significant increase in resistance to amoxicillin, from 10% in 2018 to nil in 2022. Overall, the rate of resistant Klebsiella pneumonia (K. pneumonia) increased from 7.5% (3/40) in 2018 to 21.4% (9/42) in 2022, while XDR Klebsiella pneumonia among the mechanically ventilated ICU patients significantly increased from 62.5% (25/40) in 2018 to 71% (30/42) in 2022. Conclusion K. pneumoniae antibiotic resistance is a real threat in Asia and requires close monitoring to be controlled. More careful attempts should be made to create a new generation of antimicrobials since the prevalence of resistance to existingmedications is rising. Antibiotic resistance should be monitored and reported by healthcare institutions regularly.

Detection of AcrA and AcrB Efflux Pumps in Multidrug-Resistant Klebsiella pneumonia that Isolated from Wounds Infection Patients in Al-Diwaniyah Province.

Many infections produced by multidrug-resistant (MDR) Klebsiella pneumoniae are the main cause of death and treatment restrictions worldwide. In K. pneumoniae, the efflux pump system is dangerous in drug resistance. Therefore, this study was designed to investigate the involvement of the AcrA and AcrB efflux pumps in antibiotic resistance in Klebsiella pneumoniae isolated from wound patients. During June 2021-February 2022, 87 clinical isolates of Klebsiella pneumonia bacteria were obtained from wound samples patients consulted to the hospitals in AL-Diwaniyah province, Iraq. The disc diffusion method performed an antibiotic susceptibility test after microbiological/biochemical identification. The polymerase chain reaction (PCR) technique was used to examine efflux genes' prevalence (acrA and acrB). The results showed that resistance to Carbenicillin 72 (82.7%), Erythromycin 66 (75.8%), Rifampin 58 (66.6%), Ceftazidime 52 (59.7%), Cefotaxime 44 (50.5%), Novobiocin 38 (43.6%), Tetracycline 32 (36.7%), Ciprofloxacin 22 (25.2%), Gentamicin 16 (18.3%), Nitrofurantoin 6 (10.3%) in Klebsiella pneumoniae isolates. The PCR procedure revealed that the occurrence of the acrA and acrB genes is 55 (100%) and 55 (100%), respectively. The findings of this investigation show that the AcrA and AcrB efflux pumps play a crucial character in antibiotic resistance in multidrug-resistant Klebsiella pneumoniae bacterial isolates. As a result of the unintentional transmission of antimicrobial resistance genes, precise detection of resistance genes using molecular approaches is required to switch the extent of resistant strains.

Genomic characterization of a new phage BUCT541 against Klebsiella pneumoniae K1-ST23 and efficacy assessment in mouse and Galleria mellonella larvae.

Over the past decades, the spread of multi-drug-resistant Klebsiella pneumoniae (MDR-KP) is becoming a new threat and new effective therapies against this pathogen are needed. Bacteriophage (phage) therapy is considered to be a promising alternative treatment for MDR-KP infections compared with antibacterial drug usage. Here, we reported a new phage BUCT541 which can lyse MDR-KP ST23. The genome of BUCT541 is a double-stranded linear 46,100-bp long DNA molecule with 48% GC content through the Next generation sequencing (NGS) data. A total of 81 open reading frames and no virulence or antimicrobial resistance genes are annotated in the BUCT541 genome. BUCT541 was able to lyse 7 of the 30 tested MDR-KP according to the host range analysis. And the seven sensitive strains belonged to the K. pneumoniae K1-ST23. BUCT541 exhibited high thermal stability (4–70°C) and broad pH tolerance (pH 3-11) in the stability test. The in vivo results showed that BUCT541 (4 × 105 plaque-forming units (PFU)/each) significantly increased the survival rate of K. pneumoniae infected Galleria mellonella from 5.3% to 83.3% within 48 h. Moreover, in the mouse lung infection model, high doses of BUCT541 (2 × 107 PFU/each) cured 100% of BALB/c mice that were infected with K. pneumoniae. After 30 h of treatment with phage BUCT541 of the multiplicity of infection (MOI) = 10, the K. pneumoniae in the lungs of mice was lower than 104 CFU/mL, compared to the control group 109 CFU/mL. Together, these findings indicate that phage BUCT541 holds great promise as an alternative therapy with excellent stability and a wide lysis range for the treatment of MDR-KP ST23 infection.

Characterization and Comparative Genomics Analysis of a New Bacteriophage BUCT610 against Klebsiella pneumoniae and Efficacy Assessment in Galleria mellonella Larvae.

The spread of multidrug-resistant Klebsiella pneumoniae (MDR-KP) has become an emerging threat as a result of the overuse of antibiotics. Bacteriophage (phage) therapy is considered to be a promising alternative treatment for MDR-KP infection compared with antibiotic therapy. In this research, a lytic phage BUCT610 was isolated from hospital sewage. The assembled genome of BUCT610 was 46,774 bp in length, with a GC content of 48%. A total of 83 open reading frames (ORFs) and no virulence or antimicrobial resistance genes were annotated in the BUCT610 genome. Comparative genomics and phylogenetic analyses showed that BUCT610 was most closely linked with the Vibrio phage pYD38-A and shared 69% homology. In addition, bacteriophage BUCT610 exhibited excellent thermal stability (4–75 °C) and broad pH tolerance (pH 3–12) in the stability test. In vivo investigation results showed that BUCT610 significantly increased the survival rate of Klebsiella pneumonia-infected Galleria mellonella larvae from 13.33% to 83.33% within 72 h. In conclusion, these findings indicate that phage BUCT610 holds great promise as an alternative agent with excellent stability for the treatment of MDR-KP infection.

Methylene Blue-Mediated Antimicrobial​Photodynamic Therapy Against Clinical Isolates of Extensively Drug Resistant​Gram-Negative Bacteria Causing Nosocomial Infections in Thailand,An In VitroStudy.

Background/PurposeSome multidrug-resistant gram-negative bacteria as a global threat have been recently prioritized for research and development of new treatments. We studied the efficacy of methylene blue–mediated antimicrobial photodynamic therapy (MB-aPDT) for the reduction of extensively drug-resistant Acinetobacter baumannii (XDR-AB) and Pseudomonas aeruginosa (XDR-PS) and multidrug-resistant Klebsiella pneumoniae (MDR-KP) isolated in a university hospital setting in Thailand.MethodTwo isolates of each selected bacterium were collected, XDR-AB1 and AB2, XDR- PS1 and PS2, and MDR-KP1 and KP2. Three triplicate experiments using various MB concentrations alone, various red light fluences alone, as well as the selected non-toxic doses of MB and fluences of red light combined as MB-aPDT were applied on each selected isolate. The colonies were counted [colony forming units (CFU)/ml]. Estimation of the lethal treatment dose defined as reduction of > 2 log10 in CFU/ml compared with untreated bacteria.ResultThere were generally negligible changes in the viable counts of the bacterial suspensions treated with all the MB concentrations (p > 0.05). In the second experiment with the only red light treatments, at fluences higher than 2 J/cm, reduction trend in viable counts across all the isolates was observed. Only for MDR-KP1, however, the lethal dose was achieved with the highest fluence of red light (80 J/cm). With the concentration of MB, 50 and 150 mg/L in the third experiment (MB-aPDT), the greater bacterial reduction was observed in all clinical isolates leading to their lethal viable cell reduction when escalating the light fluence to 80 J/cm.ConclusionsMB-aPDT evidently killed the selected XDR and MDR-gram negative bacteria. In highly drug-resistant crisis era, MB-aPDT could be a promising option, particularly for local infections and infection complicating chronic wounds.

Mortality Risk Factors and Prognostic Analysis of Patients with Multi-Drug Resistant Enterobacterales Infection.

BackgroundThe data from the China Network Antibacterial Surveillance Center (http://www.chinets.com) showed that the prevalence of Escherichia coli (E. coli), Klebsiella pneumoniae (KP), and Enterobacter cloacae (ecl), was 18.96%, 14.12%, and 2.74% in 2022, respectively. The resistance rates of E. coli and KP to 3rd or 4th generation cephalosporins were 51.7% and 22.1%, to carbapenems was 1.7% and 3.9%, to quinolones was 55.9% in Shanxi. The generation of extended-spectrum beta-lactamases (ESBLs) is a major mechanism resulting in drug resistance in Enterobacterales. To determine the mortality risk factors of multi-drug resistant Enterobacterales (MDRE) and multi-drug resistant Klebsiella pneumoniae (MDR-KP) infection.Methods91 MDR strains from 91 patients were collected from 2015 to 2019 in the second hospital of Shanxi Medical University. The mortality risk factors for the MDRE infections and clinical outcomes were analyzed by univariable and multivariable analysis. The independent predictors of 30-day mortality were analyzed through the Cox regression analysis including the variables with a value <0.2.ResultsThe majority of patients were admitted to ICUs. Pulmonary infection was a major infection (43.96%, 40/91). Thirty-three (36.26%, 33/91) strains of MDR-KP were only detected in 2018. The proportion of multi-drug resistant Escherichia coli (MDR E. coli) and multi-drug resistant Enterobacter cloacae (MDR ecl) were 16.48% (15/91) and 17.58% (16/91), respectively. The presence of cerebrovascular diseases (OR, 4.046; 95%Cl, 1.434–11.418; P=0.008) and central venous catheterization (OR, 4.543; 95%Cl, 1.338–15.425; P=0.015) were associated with mortality in patients with MDRE infections. Endotracheal intubation (OR, 4.654; 95%Cl, 1.5–14.438; P=0.008) was an independent mortality risk factor for patients infected with MDR-KP strains. Patients who received aminoglycoside antibiotics (P=0.057) had a higher 30-day survival rate. The β-lactam antibiotics were the major agent in the clinic.ConclusionThis study implies that patients with cerebrovascular diseases, central venous catheterization, and endotracheal intubation are at risk of carrying MDR isolates.

Prevalence of Multidrug-Resistant Klebsiella pneumoniae Clinical Isolates in Nepal.

Background Multidrug-resistant Klebsiella pneumoniae (MDR-KP) are becoming increasingly common over the world. The focus of this research was to get a quantitative assessment of K. pneumoniae and their multidrug resistance (MDR) profile in Nepal. Methods Three electronic databases: PubMed, Google Scholar, and Research4Life were used to search publications specifying K. pneumoniae infections and/or their MDR status from January 2015 to October 2021. Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines was followed for the review, and R language 4.1.1 was used for analysis. Depending upon heterogeneity of data, we used random model for pooled data to examine the prevalence of the organism and the multidrug resistance. Results Evaluation included 16 studies, and the pooled estimation of K. pneumoniae in total clinical samples was 3% (95% CI; 0.01–0.05). In the meta-analysis, 14 studies were combined for determining the prevalence of K. pneumoniae in total positive clinical isolates which was 16% (95% CI: 0.11–0.20), while from 12 research studies, MDR status in the pathogen was found to be 64% (95% CI, 0.53–0.74). Conclusion The MDR status of K. pneumoniae as well as the prevalence of the bacteria in Nepal was analyzed which showed alarming situation about administration of antibiotics and indicated choosing and developing reliable antibiotic strategies.

The Identification of Phage Vb_1086 of Multidrug-Resistant Klebsiella Pneumoniae and its Synergistic Effects with Ceftriaxone

The Identification of Phage Vb_1086 of Multidrug-Resistant Klebsiella Pneumoniae and its Synergistic Effects with Ceftriaxone

Genetic Analysis, Population Structure, and Characterisation of Multidrug-Resistant Klebsiella pneumoniae from the Al-Hofuf Region of Saudi Arabia.

Multidrug-resistant Klebsiella pneumoniae (MDR-KP) is a major public health problem that is globally associated with disease outbreaks and high mortality rates. As the world seeks solutions to such pathogens, global and regional surveillance is required. The aim of the present study was to examine the antimicrobial susceptibility pattern and clonal relatedness of Klebsiella pneumoniae isolates collected for a period of three years through pulse field gel electrophoresis (PFGE). Isolate IDs, antimicrobial assays, ESBL-production, and minimum inhibitory concentrations (MICs) were examined with the Vitek 2 Compact Automated System. IDs were confirmed by 16S rRNA gene sequencing, with the resulting sequences being deposited in NCBI databases. DNA was extracted and resistance genes were detected by PCR amplification with appropriate primers. Isolates were extensive (31%) and multidrug-resistant (65%). Pulsotype clusters grouped the isolates into 22 band profiles that showed no specific pattern with phenotypes. Of the isolates, 98% were ESBL-KP, 69% were carbapenem-resistant Enterobacteriaceae (CRE) strains, and 72.5% comprised the carriage of two MBLs (SIM and IMP). Integrons (ISAba1, ISAba2, and IS18) were detected in 69% of the MDR-KP. Additionally, OXA-23 was detected in 67% of the isolates. This study therefore demonstrates clonal diversity among clinical K. pneumoniae, confirming that this bacterium has access to an enormous pool of genes that confer high resistance-developing potential.

Topically Applied Bacteriophage to Control Multi-Drug Resistant Klebsiella pneumoniae Infected Wound in a Rat Model.

(Background): Multi-drug-resistant Klebsiella pneumoniae (MDR-KP) has steadily grown beyond antibiotic control. Wound infection kills many patients each year, due to the entry of multi-drug resistant (MDR) bacterial pathogens into the skin gaps. However, a bacteriophage (phage) is considered to be a potential antibiotic alternative for treating bacterial infections. This research aims at isolating and characterizing a specific phage and evaluate its topical activity against MDR-KP isolated from infected wounds. (Methods): A lytic phage ZCKP8 was isolated by using a clinical isolate KP/15 as a host strain then characterized. Additionally, phage was assessed for its in vitro host range, temperature, ultraviolet (UV), and pH sensitivity. The therapeutic efficiency of phage suspension and a phage-impeded gel vehicle were assessed in vivo against a K. pneumoniae infected wound on a rat model. (Result): The phage produced a clear plaque and was classified as Siphoviridae. The phage inhibited KP/15 growth in vitro in a dose-dependent pattern and it was found to resist high temperature (˂70 °C) and was primarily active at pH 5; moreover, it showed UV stability for 45 min. Phage-treated K. pneumoniae inoculated wounds showed the highest healing efficiency by lowering the infection. The quality of the regenerated skin was evidenced via histological examination compared to the untreated control group. (Conclusions): This research represents the evidence of effective phage therapy against MDR-KP.

In Vitro Susceptibility of Multi-Drug Resistant Klebsiellapneumoniae Strains Causing Nosocomial Infections to Fosfomycin. A Comparison of Determination Methods.

Introduction: Over the past few decades, Klebsiella pneumoniae strains increased their pathogenicity and antibiotic resistance, thereby becoming a major therapeutic challenge. One of the few available therapeutic options seems to be intravenous fosfomycin. Unfortunately, the determination of sensitivity to fosfomycin performed in hospital laboratories can pose a significant problem. Therefore, the aim of the present research was to evaluate the activity of fosfomycin against clinical, multidrug-resistant Klebsiella pneumoniae strains isolated from nosocomial infections between 2011 and 2020, as well as to evaluate the methods routinely used in hospital laboratories to assess bacterial susceptibility to this antibiotic. Materials and Methods: 43 multidrug-resistant Klebsiella strains isolates from various infections were tested. All the strains had ESBL enzymes, and 20 also showed the presence of carbapenemases. Susceptibility was determined using the diffusion method (E-test) and the automated system (Phoenix), which were compared with the reference method (agar dilution). Results: For the reference method and for the E-test, the percentage of strains sensitive to fosfomycin was 65%. For the Phoenix system, the percentage of susceptible strains was slightly higher and stood at 72%. The percentage of fosfomycin-resistant strains in the Klebsiella carbapenemase-producing group was higher (45% for the reference method and E-test and 40% for the Phoenix method) than in carbapenemase-negative strains (25%, 25%, and 20%, respectively). Full (100%) susceptibility categorical agreement was achieved for the E-test and the reference method. Agreement between the automated Phoenix system and the reference method reached 86%. Conclusions: Fosfomycin appears to be the antibiotic with a potential for use in the treatment of infections with multidrug-resistant Klebsiella strains. Susceptibility to this drug is exhibited by some strains, which are resistant to colistin and carbapenems. The E-test, unlike the Phoenix method, can be an alternative to the reference method in the routine determination of fosfomycin susceptibility, as it shows agreement in terms of sensitivity categories and only slight differences in MIC values. The Phoenix system, in comparison to the reference method, shows large discrepancies in the MIC values and in the susceptibility category.