In Vitro Synergistic Effect of Colistin with Fosfomycin Against Carbapenem-Resistant Klebsiella pneumoniae.

BACKGROUND: The dwindling antibiotic reserve owing to augmented drug-resistant bacteria is a major handicap for treating physicians. Klebsiella pneumoniae, a gram-negative encapsulated member of the Enterobacteriaceae family, is one such pathogenic bacteria. Carbapenemase-producing Klebsiella pneumoniae is globally recognized as one of the most critical bacterial threats to public health due to its extremely limited treatment options. Carbapenem-resistant Klebsiella pneumoniae (CRKP) infections pose therapeutic challenges due to simultaneous resistance to various other groups of antibiotics. In this study, we have evaluated the synergistic effect of fosfomycinagainst CRKP isolates when used in combination with colistin by applying the Checkerboard method. METHODS: A laboratory-based prospective study was conducted in the Department of Microbiology, JSS Hospital, Mysuru, for a period of one year after obtaining ethical clearance. Klebsiella pneumoniae isolates obtained from clinical samples were screened for carbapenem resistance by the VITEK-2 compact system (bioMérieux, Marcy-l'Étoile, France). The minimum inhibitory concentration (MIC) of colistin and fosfomycin was individually ascertained by broth microdilution (BMD). Finally, the synergistic activity of the fosfomycin-colistin combination was determined by the BMD-based Checkerboard method. RESULTS: Among the 50 CRKP isolates, 36 (72%) isolates showed synergism, eight (16%) isolates showed indifference and six (12%) isolates showed partial synergism, while none of them showed additivity and antagonism by the Checkerboard method. These results are found to be statistically significant (chi-square value of 116.204 and p-value of < 0.00001). CONCLUSION: This study showed a promising in-vitro synergy between the drugs fosfomycin and colistin by Checkerboard BMD testing protocol. Colistin being a reserve antibiotic, monotherapy comes with the limitations of higher chances of resistance as well as toxicity, which can be overcome by combination therapy, thereby decreasing CRKP-associated mortality rates and delivering holistic patient benefit.

Duration of antibiotic therapy for multidrug resistant Pseudomonas aeruginosa pneumonia: is shorter truly better?

BACKGROUND: The 2016 IDSA guideline recommends a treatment duration of at least 7 days for hospital-acquired (HAP)/ventilator-associated pneumonia (VAP). The limited literature has demonstrated higher rates of recurrence for non-glucose fermenting gram-negative bacilli with short course therapy, raising the concern of optimal treatment duration for these pathogens. Therefore, we aimed to compare the outcomes for patients receiving shorter therapy treatment (≤ 8 days) versus longer regimen (> 8 days) for the treatment of multidrug resistant (MDR) Pseudomonas pneumonia. METHODS: A single-center, retrospective cohort study was conducted to evaluate adult patients receiving an antimicrobial regimen with activity against MDR Pseudomonas aeruginosa in respiratory culture between 2017 and 2020 for a minimum of 6 consecutive days. Exclusion criteria were inmates, those with polymicrobial pneumonia, community-acquired pneumonia, and infections requiring prolonged antibiotic therapy. RESULTS: Of 427 patients with MDR P. aeruginosa respiratory isolates, 85 patients were included. Baseline characteristics were similar among groups with a median age of 65.5 years and median APACHE 2 score of 20. Roughly 75% had ventilator-associated pneumonia. Compared to those who received ≤ 8 days of therapy, no difference was seen for clinical success in patients treated for more than 8 days (80% vs. 65.5%, p = 0.16). The number of 30-day and 90-day in-hospital mortality, 30-days relapse, and other secondary outcomes did not significantly differ among the treatment groups. CONCLUSIONS: Prolonging treatment duration beyond 8 days did not improve patient outcomes for MDR P. aeruginosa HAP/VAP.

Synthesis and antibacterial activities of heterocyclic ring-fused 20(S)-protopanaxadiol derivatives.

Multidrug-resistant (MDR) bacterial infections are becoming a life-threatening issue in public health; therefore, it is urgent to develop novel antibacterial agents for treating infections caused by MDR bacteria. The 20(S)-protopanaxadiol (PPD) derivative 9 was identified as a novel antibacterial hit compound in screening of our small synthetic natural product-like (NPL) library. A series of novel PPD derivatives with heterocyclic rings fused at the C-2 and C-3 positions of the A-ring were synthesized and their antibacterial activities against Staphylococcus aureus (S. aureus) Newman strain and MDR S. aureus strains (USA300, NRS-1, NRS-70, NRS-100, NRS-108, NRS-271, XJ017, and XJ036) were evaluated. Among these compounds, quinoxaline derivative 56 (SH617) exhibited the highest activity with MICs of 0.5-4 µg/mL against the S. aureus Newman strain and the eight MDR S. aureus strains. Its antibacterial activity was comparable to that of the positive control, vancomycin. In the zebrafish, 56 revealed no obvious toxicity even at a high administered dose. In vivo, following a lethal infection induced by USA300 strains in zebrafish, 56 exhibited significantly increased survival rates in a dose-dependent manner.

Occurrence, multidrug resistance and potential risk factors for Staphylococcus aureus infection at worker-animal and working equipment interfaces: a systematic review and meta-analysis of the Ethiopian literature.

Background: Staphylococcus aureus (S. aureus) infecting animals and humans via close contact, handling, or consuming contaminated products is a growing public health concern. In Ethiopia, it is important to examine the overall prevalence of S. aureus, patterns of multidrug resistance, and potential risks in human-animal interface settings. Thus, this review was conducted to estimate the pooled prevalence of S. aureus, its multidrug resistance, and potential risk factors for worker-animal-working equipment interactions. Methods: This systematic review and meta-analysis were carried out by the PRISMA guidelines. The research articles were searched from PubMed, HINARI, Web of Sciences, and Google Scholar databases. Results: This meta-analysis included 13 independent articles and 52 dependent studies. In total, 5,329 humans, 5,475 animals, and 5,119 samples of working equipment were analyzed. The pooled prevalence of S. aureus at the interfaces between humans, animals, and working equipment was 22%, there was a high level of heterogeneity (I2 = 94%: p < 0.01). The overall pooled prevalence of S. aureus in dairy farm sources was 23% (95% CI, 17-30%) compared to 18% in abattoirs. The pooled prevalence of S. aureus was estimated to be 25% for human sources, 23% for animal sources, and 19% for working equipment. The total multidrug resistance (MDR) rate was 27%. The present study illustrates that a predominant antimicrobials comprising ampicillin, penicillin, chloramphenicol, tetracycline, and ciprofloxacin, accounts for the development of resistance in S. aureus strains, with a prevalence of 72%. According to the qualitative assessment of potential risk factors, animal age, worker education, lactation stage, and hand washing by milkers influenced the circulation of S. aureus at animal-worker and working equipment interfaces. Conclusion: The pooled prevalence of S. aureus at the interface of human,-and animal-working equipment was quantified at 22%. S. aureus was found in humans, animals, and equipment at nearly the same rate. The results of this study demonstrate that S. aureus is hazardous and circulates among animals, workers, and equipment: farmers, animal owners, employees, and the public need to be educated about S. aureus. Moreover, animals and work equipment should be included in the control and prevention of S. aureus infection.

Chemokines Kill Bacteria by Binding Anionic Phospholipids without Triggering Antimicrobial Resistance.

Classically, chemokines coordinate leukocyte trafficking during immune responses; however, many chemokines have also been reported to possess direct antibacterial activity in vitro. Yet, the bacterial killing mechanism of chemokines and the biochemical properties that define which members of the chemokine superfamily are antimicrobial remain poorly understood. Here we report that the antimicrobial activity of chemokines is defined by their ability to bind phosphatidylglycerol and cardiolipin, two anionic phospholipids commonly found in the bacterial plasma membrane. We show that only chemokines able to bind these two phospholipids kill Escherichia coli and Staphylococcus aureus and that they exert rapid bacteriostatic and bactericidal effects against E. coli with a higher potency than the antimicrobial peptide beta-defensin 3. Furthermore, our data support that bacterial membrane cardiolipin facilitates the antimicrobial action of chemokines. Both biochemical and genetic interference with the chemokine-cardiolipin interaction impaired microbial growth arrest, bacterial killing, and membrane disruption by chemokines. Moreover, unlike conventional antibiotics, E. coli failed to develop resistance when placed under increasing antimicrobial chemokine pressure in vitro. Thus, we have identified cardiolipin and phosphatidylglycerol as novel binding partners for chemokines responsible for chemokine antimicrobial action. Our results provide proof of principle for developing chemokines as novel antibiotics resistant to bacterial antimicrobial resistance mechanisms.

Drug resistance in drug-resistant tuberculosis patients with and without diabetes mellitus: a comparative analysis.

BACKGROUND: This dual burden of tuberculosis (TB) and diabetes mellitus (DM) has become a global public health concern. This study aims to compare drug resistance in drug-resistant tuberculosis (DR-TB) patients with and without DM and analyse the risk factors of multidrug-resistant tuberculosis (MDR-TB). METHODS: A total of 893 DR-TB patients were admitted to Wenzhou Central Hospital between January 2018 and December 2022. After excluding 178 cases with incomplete clinical and laboratory data, 715 patients were included in the study. These patients were then categorized into two groups based on the presence of type 2 DM: the DM group (160 cases) and the non-DM group (555 cases). Demographic information, baseline clinical characteristics, laboratory and imaging test results, clinical diagnoses, and other relevant data were collected for analysis. Statistical analysis was conducted on demographic information, clinical parameters, drug resistance spectrum, and risk factors for multidrug resistance. RESULTS: In both the DM and non-DM groups, the order of resistance to first-line anti-tuberculosis drugs is isoniazid, streptomycin, rifampicin, and ethambutol. There is no significant difference in the proportion of mono-resistant tuberculosis, polydrug-resistant tuberculosis, and multidrug-resistant tuberculosis between the two groups (P > 0.05). The prevalence of MDR-TB in both groups shows a downward trend between 2018 and 2022, but the trend is not statistically significant (P > 0.05). Among patients without DM, residence in rural areas, retreatment of tuberculosis, pulmonary cavity, and uric acid ≥ 346 µmol/L are identified as independent risk factors for MDR-TB. Among patients with DM, residence in rural areas, retreatment of tuberculosis, pulmonary cavity, and HbA1c ≥ 9.8% were identified as independent risk factors for MDR-TB. CONCLUSION: Isoniazid is the most resistant drug among DR-TB patients with and without DM. There is no statistically significant difference in drug resistance patterns between the two groups. Some progress has been made in the prevention and control of DR-TB in this area, but the effect is not very significant. There are differences in the risk factors of MDR-TB between patients with and without DM.

Colonisation with multidrug-resistant organisms among dialysis patients at Universitas Academic Hospital.

Background: While most infections with multidrug-resistant organisms (MDROs) affect colonised people, there is limited evidence on MDRO colonisation in South African dialysis patients. Objectives: This study evaluated the prevalence of MDRO colonisation among dialysis patients, the resistance patterns of each MDRO and the risk factors for colonisation. Method: Rectal and nasal swabs were collected from dialysis patients who consented to participate in a 5-month study to identify selected MDROs (April 2021 - August 2021). Specimens were cultured on selected chromogenic media. Data collected included demographics, clinical information from medical records and laboratory results. Results: Multidrug-resistant organisms were isolated from 17 (23.9%) of the 71 enrolled participants. Of the 23 MDRO strains from rectal swabs (n = 71), extended-spectrum beta-lactamase-producing Enterobacterales accounted for 21.1% (15/71), vancomycin-resistant enterococci 2.8% (n = 2/71) and carbapenem-resistant Enterobacterales 4.2% (n = 3/71). Klebsiella pneumoniae (65.2%, n = 15/23) was the most prevalent MDRO. More than 80% resistance to trimethoprim and sulfamethoxazole, cefotaxine, and ciprofloxacin was noted. Significant risk factors included previous hospitalisation, proton pump inhibitor use and antibiotic exposure in the past 6 months. Conclusion: Multidrug-resistant organisms' carriage was high in our dialysis population. The infection prevention and control measures need to be revised and strengthened. Contribution: This study falls within the scope of the SAJID journal as it is the first within sub-Sahara Africa to report that approximately one-fifth of dialysis patients were colonised with MDRO, which is a significant risk for MDRO infections.

Are Nurses Aware of Their Contribution to the Antibiotic Stewardship Programme? A Mixed-Method Study from Qatar.

The antibiotic stewardship programme (ASP) is a new concept initiated by WHO, but nurses are not yet ready to adopt the program. The training and empowerment of nurses are the best strategies for enhancing their knowledge and engagement in ASP. This mixed-method study was used to assess perceived roles and barriers of nurses' involvement in ASP. An online survey was conducted among 420 clinical nurses to identify their role, and 23 individual interviews were performed among nurses and infection control practitioners to explore the barriers and recommendations to overcome the identified barriers. The majority of the nurses agreed with the sixteen identified roles in ASP, of which 'antibiotic dosing and de-escalation' (82.61%), 'IV to PO conversion of antibiotic, outpatient antibiotic therapy' (85.23%), and 'outpatient management, long-term care, readmission' of the patients (81.19%) had the lowest agreement from the participants. The major themes generated through the qualitative interviews were a lack of knowledge about ASP, poor communication between multidisciplinary teams, lack of opportunity and multidisciplinary engagement, lack of formal education and training about ASP, lack of ASP competency and defined roles in policy, role conflict or power/position, availability of resources, and lack of protected time. Nurses play an integral role in the successful implementation of antibiotic stewardship programs. The empowerment of nurses will help them to adopt the unique role in ASP. Nurses can significantly contribute to antibiotic stewardship efforts and improve patient outcomes through addressing these challenges.

The Guardian of Vision: Intelligent Bacteriophage-Based Eyedrops for Clinical Multidrug-Resistant Ocular Surface Infections.

Clinical multidrug-resistant Pseudomonas aeruginosa (MDR-PA) is the leading cause of refractory bacterial keratitis (BK). However, the reported BK treatment methods lack biosecurity and bioavailability, which usually causes irreversible visual impairment and even blindness. Herein, for BK caused by clinically isolated MDR-PA infection, armed phages are modularized with the type I photosensitizer (PS) ACR-DMT, and an intelligent phage eyedrop is developed for combined phagotherapy and photodynamic therapy (PDT). These eyedrops maximize the advantages of bacteriophages and ACR-DMT, enabling more robust and specific targeting killing of MDR-PA under low oxygen-dependence, penetrating and disrupting biofilms, and efficiently preventing biofilm reformation. Altering the biofilm and immune microenvironments alleviates inflammation noninvasively, promotes corneal healing without scar formation, protects ocular tissues, restores visual function, and prevents long-term discomfort and pain. This strategy exhibits strong scalability, enables at-home treatment of ocular surface infections with great patient compliance and a favorable prognosis, and has significant potential for clinical application.

Therapeutic insights: Use of ceftazidime-avibactam in pediatric patients.

BACKGROUND: The increasing worldwide prevalence of multidrug-resistant (MDR) bacteria underscores the pressing demand for innovative therapeutic solutions. Ceftazidime-avibactam (CAZ-AVI) represents a promising new drug combination that has received approval for specific infection types. However, there is limited information regarding its application in pediatric patients. METHODS: This study investigates the effectiveness and adverse reactions associated with CAZ-AVI treatment in pediatric patients with life-threatening infections caused by MDR pathogens. The study was conducted at a tertiary children's hospital between December, 2021 and July, 2023. RESULTS: A total of 21 patients with life-threatening infections caused by MDR pathogens were enrolled in the study. All patients had underlying medical conditions: 10 had cerebral palsy, four had congenital neurometabolic disease, two had Nieman-Pick disease, two had cystic fibrosis, two had primary immunodeficiency, and one had leukemia. Among these, 12 patients had tracheostomies. Eight patients received CAZ- AVI monotherapy, and 13 patients received combination therapy. Microbiological eradication was achieved in 18 patients (85.7%), and a clinical response was observed in 20 patients (95.2%). Two patients (9.5%) experienced relapse with the same bacteria. One patient developed anaphylaxis, and one patient had elevated creatine phosphokinase levels that normalized following discontinuation of treatment. One patient died during the study period due to gastrointestinal bleeding. CONCLUSIONS: Ceftazidime-avibactam may be a promising new drug option for the treatment of life-threatening infections caused by MDR Gram-negative microorganisms in pediatric patients. However, further studies with larger case series are needed to further evaluate the efficacy and safety of CAZ-AVI in this population.

Factors associated with mortality among laboratory-diagnosed drug-resistant tuberculosis patients on treatment, KwaZulu-Natal Province, 2017-2019.

Introduction: tuberculosis (TB) remains a leading cause of death in South Africa. KwaZulu-Natal (KZN) is one of the provinces with a high burden of TB/drug-resistant TB cases and deaths. We determined predictors for mortality among drug-resistant TB patients on treatment in KZN province. Methods: we conducted a retrospective cohort study using secondary data from the Electronic Drug-Resistant Tuberculosis Register. We used a modified Poisson regression model with robust standard errors to determine predictors for drug-resistant TB mortality. Results: of the 7,692 eligible patients, 1,234 (16.0%) died. Males predominated (707, 57.3%) and the median age was 36 years (Interquartlile Range: 29-45 years). The majority (978, 79.2%) were HIV-TB co-infected with 911 (93%) on antiretroviral treatment (ART). The predictors included HIV-TB co-infection without ART (aIRR 3.4; 95% CI: 2.3-5.1), unknown ART status (aIRR: 1.8; 95% CI: 1.4-2.3), aged ≥60 years (aIRR: 2.1; 95% CI: 1.6-2.7), previous drug-resistant TB (aIRR: 1.5; 95% CI: 1.2-1.8) and exposure to second-line drugs (aIRR: 1.7; 95% CI: 1.4-2.0). Other predictors were hospitalization during treatment initiation (aIRR 2.5; 95% CI 2.0-3.1), initiation in other treatment facilities (aIRR: 2.2; 95% CI: 1.6-2.9) and rifampicin-resistant (aIRR: 1.2; 95% CI: 1.1-1.4). Bedaquiline fumarate was a significant protective factor against death (aIRR: 0.5; 95% CI: 0.4-0.5). Conclusion: older age, HIV co-infection without ART, hospitalization for treatment initiation, exposure to second-line drugs and a previous episode of drug-resistant TB were predictors for DR-TB mortality. Early treatment initiation and provision of antiretroviral treatment for all co-infected patients may reduce DR-TB mortality in the Province.

Biogenic silver nanomaterials synthesized from Ocimum sanctum leaf extract exhibiting robust antimicrobial and anticancer activities: Exploring the therapeutic potential.

There is a surge in antibiotic consumption because of the emergence of resistance among microbial pathogens. In the escalating challenge of antibiotic resistance in microbial pathogens, silver nanoparticles (AgNPs)-mediated therapy has proven to be the most effective and alternative therapeutic strategy for bacterial infections and cancer treatment. This study aims to explore the potential of OsAgNPs derived from Ocimum sanctum's aqueous leaf extract as antimicrobial agents and anticancer drug delivery modalities. This study utilized a plant extract derived from Ocimum sanctum (Tulsi) leaves to synthesize silver nanoparticles (OsAgNPs), that were characterized by FTIR, TEM, SEM, and EDX. OsAgNPs were assessed for their antibacterial and anticancer potential. TEM analysis unveiled predominantly spherical or oval-shaped OsAgNPs, ranging in size from 4 to 98 nm. The (MICs) of OsAgNPs demonstrated a range from 0.350 to 19.53 µg/ml against clinical, multidrug-resistant (MDR), and standard bacterial isolates. Dual labelling with ethidium bromide and acridine orange demonstrated that OsAgNPs induced apoptosis in HeLa cells. The OsAgNPs-treated cells showed yellow-green fluorescence in early-stage apoptotic cells and orange fluorescence in late-stage cells. Furthermore, OsAgNPs exhibited a concentration-dependent decrease in HeLa cancer cell viability, with an IC50 value of 90 µg/ml noted. The study highlights the remarkable antibacterial efficacy of OsAgNPs against clinically significant bacterial isolates, including antibiotic-resistant strains. These results position the OsAgNPs as prospective therapeutic agents with the potential to address the growing challenges posed by antibiotic resistance and cervical cancer.

Clinical characteristics and risk factor analysis of recipients with multidrug-resistant bacterial bloodstream infections after liver transplantation: a single-centre retrospective study.

Background: The clinical characteristics and associated risk factors for recipients who experience multidrug-resistant organism (MDRO) bloodstream infections after liver transplantation are poorly understood. This study aimed to analyse the clinical characteristics and epidemiology of pathogenic bacteria and identify associated risk factors in patients who underwent MDRO after liver transplantation. Method: We retrospectively collected data on recipients who developed bloodstream infections after liver transplantation between 2018 and 2023. Recipients were divided into MDRO and non-MDRO groups based on blood culture results. We explored the risk factors for MDRO bloodstream infections post-transplantation and summarised the clinical features, pathogen epidemiology, and prognosis. A multivariate logistic regression analysis was conducted to identify significant risk factors. Results: A total of 463 liver transplant recipients were studied, and 73 developed blood infections. There were 29 MDRO cases. The mean duration of the episodes was 26 days (range: 1-474 days). Among these patients, 22 (30.1%) developed blood infections without fever (temperature < 37.3°C), and 33 patients (45.2%) had a white blood cell count between 4 and 10 × 109/L. Among the 108 positive blood cultures, 29 genera were detected, predominantly gram-negative bacilli (n = 64, 58.2%). The detection rate for multidrug-resistant bacilli was 31.8% (35/110), with the abdomen being the most common site of origin (21.3%). Factors such as a history of preoperative intensive care unit (ICU) hospitalisation (p < 0.001) and a preoperative international normalised ratio (INR) > 2 (p < 0.048) were identified as risk factors in multivariate regression analysis. Conclusion: Multidrug-resistant bacterial bloodstream infections after liver transplantation tend to occur early in the postoperative period (<30 days) and are associated with high mortality and a lack of specific clinical manifestations. A history of preoperative intensive care unit (ICU) hospitalisation and an international normalised ratio (INR) > 2 may be risk factors for multidrug-resistant bacterial bloodstream infections after liver transplantation.

Antimicrobial resistance: use of phage therapy in the management of resistant infections.

The emergence and increase in antimicrobial resistance (AMR) is now widely recognized as a major public health challenge. Traditional antimicrobial drugs are becoming increasingly ineffective, while the development of new antibiotics is waning. As a result, alternative treatments for infections are garnering increased interest. Among these alternatives, bacteriophages, also known as phages, are gaining renewed attention and are reported to offer a promising solution to alleviate the burden of bacterial infections. This review discusses the current successes of phage therapy (PT) against multidrug-resistant organisms (MDROs), such as Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, and Enterobacter spp. The review also compares the efficacy of PT with that of chemical antibiotics, reporting on its benefits and limitations, while highlighting its impact on the human gut microbiome and immune system. Despite its potential, phage therapy is reported to face challenges such as the narrow antibacterial range, the complexity of developing phage cocktails, and the need for precise dosing and duration protocols. Nevertheless, continued research, improved regulatory frameworks, and increased public awareness are essential to realize its full potential and integration into standard medical practice, paving the way for innovative treatments that can effectively manage infections in an era of rising antimicrobial resistance.

Antimicrobial resistance profiles and genome characteristics of Klebsiella isolated from the faeces of neonates in the neonatal intensive care unit.

Introduction. Klebsiella spp. are important bacteria that colonize the human intestine, especially in preterm infants; they can induce local and systemic disease under specific circumstances, including inflammatory bowel disease, necrotizing enterocolitis and colorectal cancer.Hypothesis. Klebsiella spp. colonized in the intestine of the neonates in the neonatal intensive care unit (NICU) may be associated with disease and antibiotic resistance, which will be hazardous to the children.Aim. Our aim was to know about the prevalence, antimicrobial resistance and genome characteristics of Klebsiella spp. in neonate carriers.Methodology. Genome sequencing and analysis, and antimicrobial susceptibility testing were mainly performed in this study.Results. The isolation rates of Klebsiella spp. strains were 3.7% (16/436) in 2014 and 4.3% (18/420) in 2021. Cases with intestinal-colonized Klebsiella spp. were mainly infants with low birth weights or those with pneumonia or hyperbilirubinemia. According to the core-pan genomic analysis, 34 stains showed gene polymorphism and a sequence type (ST) of an emerging high-risk clone (ST11). Eight strains (23.5%) were found to be resistant to 2 or more antibiotics, and 46 genes/gene families along with nine plasmids were identified that conferred resistance to antibiotics. In particular, the two strains were multidrug-resistant. Strain A1256 that is related to Klebsiella quasipneumoniae subsp. similipneumoniae was uncommon, carrying two plasmids similar to IncFII and IncX3 that included five antibiotic resistance genes.Conclusion. The prevention and control of neonatal Klebsiella spp. colonization in the NICU should be strengthened by paying increased attention to preventing antimicrobial resistance in neonates.

Characterization of a novel phage against multidrug-resistant Klebsiella pneumoniae.

Multidrug-resistant Klebsiella pneumoniae (MDR-KP) poses a significant challenge in global healthcare, underscoring the urgency for innovative therapeutic approaches. Phage therapy emerges as a promising strategy amidst rising antibiotic resistance, emphasizing the crucial need to identify and characterize effective phage resources for clinical use. In this study, we introduce a novel lytic phage, RCIP0100, distinguished by its classification into the Chaoyangvirus genus and Fjlabviridae family based on International Committee on Taxonomy of Viruses (ICTV) criteria due to low genetic similarity to known phage families. Our findings demonstrate that RCIP0100 exhibits broad lytic activity against 15 out of 27 tested MDR-KP strains, including diverse profiles such as carbapenem-resistant K. pneumoniae (CR-KP). This positions phage RCIP0100 as a promising candidate for phage therapy. Strains resistant to RCIP0100 also showed increased susceptibility to various antibiotics, implying the potential for synergistic use of RCIP0100 and antibiotics as a strategic countermeasure against MDR-KP.

Identification of clusters of secondary metabolite biosynthetic genes in the Camelina sativa genome.

Multidrug-resistant pathogens pose an earnest risk to human health. Therefore, new antibiotics need to be developed quickly. Most of the antibiotics we use today are derived from secondary metabolites, which are produced by plants. Genome mining tools allow us to detect biosynthetic gene clusters (BGCs) responsible for the production of secondary metabolites. Focusing on the most promising BGCs-coding antibiotics with unique pathways is currently a challenge. In silico approach like genome mining are used to visualise the action of these bioactive chemicals. Camelina sativa is a well-known medicinal plant and it would be interesting to study its secondary metabolites. In this work, we found seven bioactive compounds in this plant using the genome mining approach. Further, the clusters of genes involved in the biosynthesis of these compounds were analysed with their metabolic pathways. This work illuminates new ground on the evolution of BGCs for the nutritional improvement of C. sativa.

Poultry slaughterhouse wastewater as a source of bacterial antimicrobial resistance.

Slaughterhouses produce huge volumes of effluents throughout the production chain that, when discharged untreated into bodies of water, can become a source of environmental contamination. This is particularly worrisome if these effluents are used for irrigation since they increase contamination levels and spread pathogens and resistance determinants to humans and animals. Therefore, in this study, we assessed antimicrobial resistance in bacteria isolated from inlet water, equalization wastewater tanks, treatment plant wastewater, and treated wastewater in slaughterhouse facilities in Rio de Janeiro, Brazil. Four samples were collected at each of the collection points, between June 2021 and July 2022. Following bacterial isolation and identification, the samples were analyzed for antimicrobial resistance using the disk diffusion method to test aminoglycoside, beta-lactam, and fluoroquinolone antimicrobials. A total of 229 bacteria were isolated, with 74 isolates selected from the genera Citrobacter (12), Enterobacter (14), Klebsiella (35), Serratia (5), and Pseudomonas (8). Inlet water had the lowest number of isolates and was the only point with gentamicin-resistant isolates. Raw effluent from the equalization tank showed the highest number of isolated bacteria and resistance levels, followed by treated wastewater and the treatment plant. Across all samples, a high rate of cefoxitin-resistance was observed among the isolated bacteria. Klebsiella pneumoniae stood out as the species that demonstrated the greatest resistance to a variety of antimicrobials. These results highlight the importance of water quality monitoring in mitigating public health and environmental risks and high antimicrobial resistance levels.

Two outbreaks and sporadic occurrences of Candida auris from one hospital in China: an epidemiological, genomic retrospective study.

OBJECTIVES: To investigate the clinical relevance, origin, transmission, and resistance of Candida auris (C. auris) isolates from two outbreaks and sporadic occurrences from one hospital in China. METHODS: A total of 135 C. auris isolates were collected. Clinical characteristics were obtained and antifungal susceptibility testing (AFST) was performed using the method of broth microdilution. Phylogenetic tree, WGS analysis, and single nucleotide polymorphisms (SNPs) were used to determine the origin, transmission, and resistance mechanisms. RESULTS: A total of 31 patients (91.2%, 31/34) received invasive medical procedures and 13 patients (38.2%, 13/34) had antifungal agents before C. auris infection/colonization, except one patient whose clinical information was missing. Only 4 cases of C. auris candidemia were observed. 18 patients died, 13 patients recovered, and the outcomes of 3 patients were not available. A total of 35 C. auris isolates, which were successfully cultivated and the first isolated or harbored specific drug-resistant phenotype from each patient, were selected to be sequenced and further analyzed. C. auris isolates presented low genetic variability and belonged to clade I, possibly originating from BJ004-H7 in Beijing. All 35 isolates were resistant to Fluconazole (FCZ) and amphotericin B (AMB), and 3 isolates were resistant to caspofungin (CAS). Mutations in ERG11 and FKS1 were linked to reduced azole and echinocandin susceptibility, respectively. CONCLUSIONS: Two outbreaks of highly clonal, multidrug-resistant C. auris isolates within the medical facility were reported. The intensive performance of disinfection measures helped block in-hospital transmission. Understanding the epidemiology, drug resistance and management of C. auris will be helpful for implementing effective infection control and treatment strategies.

Towards evidence-based empiric antibiotic recommendations for spontaneous infections in patients with cirrhosis.

BACKGROUND: With the emergence of multidrug-resistant infections, healthcare professionals must evaluate the effectiveness of empiric antibiotic treatments. AIMS: To assess the antibiotic susceptibility patterns of microorganisms causing spontaneous infections in patients with cirrhosis and to evaluate the suitability of empiric antibiotic treatments based on major clinical guidelines. METHODS: This cross-sectional study utilized two datasets from prospective studies of patients with cirrhosis and culture-positive spontaneous bacterial infections in Argentina and Uruguay. We estimated susceptibility to commonly used antibiotics and assessed coverage following European and American recommendations. RESULTS: We analyzed 238 episodes of culture-positive spontaneous infections in 229 patients. When implementing the recommendations for empiric treatment of community-acquired spontaneous infections, ceftazidime would result in 39 % coverage, whereas ceftriaxone would reach 70 %. Cefepime, which is not included in the recommendations, would have provided coverage of 74 %. Using ertapenem for nosocomial infections would have only covered 56 % of these episodes, whereas meropenem or imipenem reached 73 % coverage. Only the combination of meropenem or imipenem plus vancomycin would achieve a coverage surpassing 85 % in healthcare-associated or nosocomial spontaneous bacterial infections. CONCLUSIONS: Our study uncovers inadequate coverage in specific clinical scenarios when adhering to recommendations, underscoring the necessity of guidelines based on local epidemiological data.