Multidrug-resistant Organisms Research Articles

Antimicrobial Resistance Genes in Clinical Escherichia coli Strains from Livestock and Poultry in Shandong Province, China During 2015–2020

Antimicrobial resistant (AMR) Escherichia coli (E. coli) isolated from animals may lead to antibiotic treatment failure and economic losses to farmers. The co-existence of antimicrobial resistant genes (ARGs) in the same isolate presents a major challenge for the prevention and control of infection in multidrug-resistant (MDR) Gram-negative organisms. There have been a lot of studies on the antibiotic resistance of E. coli in livestock and poultry, but few of them have focused on clinical pathogens. Objective: The aim of this study was to explore the genetic characteristics, co-occurrence, and correlations between ARGs of E. coli isolated from the pathological tissues of livestock and poultry in Shandong Province, East China during 2015–2020. Methods: A total of 158 E. coli strains were collected and subjected to antimicrobial susceptibility testing and sequencing by whole-genome Next Generation Sequencing (NGS). Results: MDR strains accounted for 46.20% of the 158 E. coli strains with the highest resistant rate of ciprofloxacin (71.52%). In addition, strains with blaNDM-5/mcr-1.1 and mcr-1.1/mcr-3.24 were found in chickens, while three strains with Tet(X4) were found in pigs. In addition, the most common serotypes detected were the O serotype (76/158) and H serotype (36/158). Moreover, seventy-one STs were found and the most common STs were ST10 (6.33%), ST155 (6.33%), and ST101 (5.69%). The genetic environment analysis of the phylogroups revealed that E. coli belonging to phylogroup B1, phylogroup A, and phylogroup C constituted 39.87%, 27.85%, and 15.19%, respectively. Through the correlation analysis, mcr genes were observed to have certain relationships with ARGS such as blaTEM, floR, catA/B, and oqx. Conclusions: This study demonstrates the high prevalence and gene diversity of MDR E. coli isolated from a clinic in Shandong Province, East China. We predicted the transmission risk of animal-borne Tet(X4)-bearing and mcr-harboring E. coli to public health and provided insight into the relationship of co-existence or co-transfer between mcr with ARGS. These relationships present a great challenge for the infection control of MDR Gram-negative organisms.

Factors associated with multidrug-resistant organism (MDRO) mortality: an analysis from the national surveillance of multidrug-resistant organism, 2018-2022

IntroductionAntimicrobial resistance is a global issue, with the World Health Organization identifying it as one of the greatest threats to public health, with an estimated 4.95 million deaths linked to bacterial AMR in 2019. Our study aimed to determine the prevalence of mortality among multidrug-resistant organism (MDRO)-infected patients in state hospitals and major specialist hospitals and to identify risk factors that could be associated with mortality outcomes.MethodsThis is a cross-sectional study performed at 28 hospitals under the Ministry of Health, Malaysia, involved in the National Surveillance of Multidrug-Resistant Organism, which surveys 6 MDROs (Acinetobacter baumanii, extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli, extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae, carbapenem-resistant Entrobacterales (CRE), methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE)).ResultsIn terms of mortality, 9.6% (n = 951) of the patients died overall, whereas 90.4% (n = 8931) of the patients survived. Healthcare-acquired infection (HCAI) poses a high risk of mortality, with an adjusted odds ratio (aOR) of 2.91 (95% CI: 2.15–3.94). The presence of sterile specimens was significantly associated with increased mortality risk (aOR: 2.33, 95% CI: 2.02–2.68). Gram-negative bacteria had a greater mortality risk (aOR 1.63 95% CI: 1.37–1.93), whereas Acinetobacter baumanii had the highest prevalence of 30.7% (3033) among the 6 MDRO organisms isolated. Patients in medical-based departments had a greater mortality risk (aOR: 1.47, 95% CI: 1.22–1.75).ConclusionHCAIs, Gram-negative bacteria, sterile specimens, medical-based departments and state hospitals have been shown to be associated with increased mortality risk in patients with MDRO infections. Improved surveillance and reporting mechanisms are necessary to better understand the burden of MDRO infections and guide research funding allocation.

Effect of Fecal Microbiota Transplant on Antibiotic Resistance Genes Among Patients with Chronic Pouchitis.

Pouchitis is common among patients with ulcerative colitis (UC) who have had colectomy with ileal pouch-anal anastomosis. Antibiotics are first-line therapy for pouch inflammation, increasing the potential for gut colonization with multi-drug resistant organisms (MDRO). Fecal microbial transplant (FMT) is being studied in the treatment of pouchitis and in the eradication of MDRO. Prior work using aerobic antibiotic culture disks suggests that some patients with chronic pouchitis may regain fluoroquinolone sensitivity after FMT. However, gut MDRO include anaerobic, fastidious organisms that are difficult to culture using traditional methods. We aimed to assess whether FMT reduced the abundance of antibiotic resistance genes (ARG) or affected resistome diversity, evenness, or richness in patients with chronic pouchitis. We collected clinical characteristics regarding infections and antibiotic exposures for 18 patients who had previously been enrolled in an observational study investigating FMT as a treatment for pouchitis. Twenty-six pre- and post-FMT stool samples were analyzed using FLASH (Finding Low Abundance Sequences by Hybridization), a CRISPR/Cas9-based shotgun metagenomic sequence enrichment technique that detects acquired and chromosomal bacterial ARGs. Wilcoxon rank sum tests were used to assess differences in clinical characteristics, ARG counts, resistome diversity and ARG richness, pre- and post-FMT. All 13 of the patients with sufficient stool samples for analysis had recently received antibiotics for pouchitis prior to a single endoscopic FMT. Fecal microbiomes of all patients had evidence of multi-drug resistance genes and ESBL resistance genes at baseline; 62% encoded fluoroquinolone resistance genes. A numerical decrease in overall ARG counts was noted post-FMT, but no statistically significant differences were noted (P = 0.19). Richness and diversity were not significantly altered. Three patients developed infections during the 5-year follow-up period, none of which were associated with MDRO. Antibiotic resistance genes are prevalent among antibiotic-exposed patients with chronic pouchitis. FMT led to a numerical decrease, but no statistically significant change in ARG, nor were there significant changes in the diversity, richness, or evenness of ARGs. Further investigations to improve FMT engraftment and to optimize FMT delivery in patients with inflammatory pouch disorders are warranted.

Trends in the epidemiology of intravascular device-associated bacteremia among French hematology patients: insights from the SPIADI prospective multicenter study, 2020-2024.

Hematology patients require central venous catheters for cancer treatment and nutrition, which increases their risk of intravascular device-associated bacteremia. In the absence of recent data, we investigated intravascular device-associated bacteremia in this specific context. A three-month surveillance was conducted annually in 27 hematology wards, using a protocol derived from the HAI-Net ICU ECDC protocol (2020-2024). We analyzed the characteristics of infected patients, the sources and microorganisms of healthcare-associated bacteremias, and intravascular device-associated bacteremias (including catheter type: central venous catheter (CVC), implantable venous access device (IVAD), peripherally inserted central catheter (PICC), midline catheter (MID), and peripheral venous catheter (PVC)), the time between catheter insertion and infection onset, and bacteremia incidence rates per 1,000 patient-days. Over the five-year period, 1,835 patients experienced healthcare-associated bacteremia. No significant changes were observed in patient characteristics over the five-year period. The two primary sources of bacteremias were intravascular devices (n = 682; 37.2%) and the digestive tract (n = 467; 25.4%). The incidence rates of intravascular device-associated bacteremias acquired in the participating wards remained stable. Among the 682 intravascular device-associated bacteremias, 648 (95.0%) involved central venous catheters, primarily PICCs (42.8%), IVADs (25.6%), and CVCs (24.8%). The types of central venous catheters involved shifted over the five years, with a decrease in the proportion of CVCs (from 31.1% in 2020 to 16.8% in 2024) and, conversely, an increase in PICCs (from 35.2% in 2020 to 52.8% in 2024; p = 0.007). Among the microorganisms identified, coagulase-negative Staphylococci (n = 330; 40.6%) and Enterobacterales (21.9%) were the most common. Overall, 59 bacteremias (8.6%) were associated with multidrug-resistant organisms, with no significant trend over the study period. Of the 682 cases, 88.2% were nosocomial, while 11.8% were acquired following care provided in the community or at home. The two groups of bacteremias did not differ regarding microorganisms, and the increasing proportion of PICC-associated bacteremias was noted in both populations. In contrast, the proportion of bacteremias acquired in the community or at home significantly increased over the five-year period, starting in 2022 (6.9% of bacteremias in 2020, 6.5% in 2021, 11.8% in 2022, 16.4% in 2023, and 18.0% in 2024; p = 0.006), at the expense of nosocomial bacteremias. PICC-associated bacteremias were more common in patients with bacteremias acquired in the community or at home (57.7% vs. 40.3% for nosocomial bacteremias; p = 0.021). In addition, while most intravascular device-associated bacteremias involving central venous catheters were late-onset, with the time between catheter insertion and the onset of bacteremia exceeding 7 days in 84.8% of cases, nosocomial bacteremias were less frequently late-onset (82.8%) compared to those acquired outside healthcare institutions (97.3%; p = 0.002). The mechanisms behind the increase in the proportion of PICC-associated bacteremias occurring long after catheter placement and acquired in hematology wards or in the community/at home should be investigated. Given that Staphylococci, common components of the skin flora, are involved in approximately half of PICC-associated bacteremias, our findings raise concerns about adherence to aseptic techniques during line manipulations and catheter dressing changes, both in hematology wards and in community settings. Therefore, to improve the prevention of PICC-associated bacteremias in patients, our data should encourage local infection prevention teams to implement targeted educational programs to reinforce strict aseptic practices during catheter manipulations and dressing changes. As these procedures are increasingly performed outside hospitals, training should be extended beyond healthcare workers in hematology wards to include those providing home care.

Dealing With Antibiotic Prophylaxis in Lung Transplantation in the Era of Multidrug Resistance: The Milano Algorithm.

Infectious complications significantly impact morbidity and mortality following lung transplantation (LuTx), with over 25% of post-transplant deaths attributed to infections. Antibiotic prophylaxis during the surgical procedure is crucial for reducing early infections, though the current use of wide-spectrum antibiotics, especially in cases of multidrug-resistant organisms (MDROs), is contentious and varies widely across centre. This practice raises concerns about antimicrobial resistance (AMR), particularly in immunosuppressed patients requiring lifelong healthcare access. Syndromic multiplex polymerase chain reaction (mPCR) tests, which detect multiple pathogens simultaneously, have shown promise in quickly identifying pathogens and resistance mechanisms, thus enabling targeted treatments. However, their application in LuTx has been limited.

Investigating Gram-negative bacilli isolates’ sensitivity to ceftazidime/avibactam

ABSTRACT Background: Multidrug resistant (MDR) Gram negative organisms are becoming increasingly common. Carbapenem resistant Enterobacterales (CRE) pose a major threat and necessitate the development of new antibiotics. MDR and carbapenem resistant infections, which are common in intensive care units and hospitals, lead to increased morbidity, mortality, prolonged hospital stays, and higher healthcare costs. New antimicrobials such as ceftazidime avibactam offer potential alternatives to conventional treatments such as tigecycline and colistin, which have significant side effects and limitations. Aim: This study focuses on the antibiotic susceptibility of ceftazidime/ avibactam to Gram negative bacilli found in a large number of clinical samples collected from a tertiary care facility in Netaji Subhas Medical University and Hospital, Bihta, India. Methodology: The study included 81 Gram negative bacteria isolated from patient samples. Based on the Clinical Laboratory Standards Institute guidelines mentioned in the Kirby Bauer disc diffusion method. Result and Conclusion: the results showed that ceftazidime avibactam inhibited 89.9% of the Enterobacteriaceae isolates, which was higher than the 80.3% of amikacin and the 85.1% of meropenem. Ceftazidime avibactam was effective against CRE isolates in 69.9% of cases and against MDR isolates in urine in 94% of cases, which was higher than the 40% of ceftriaxone and 94% of nitrofurantoin. The results show that ceftazidime avibactam can cure MDR and CRE infections, especially urinary tract infections, better than conventional antibiotics, which is a great help in the fight against increasing antibiotic resistance.

Improving Antibiotic Use in Argentine Pediatric Hospitals: A Process Evaluation Using Normalization Process Theory.

In the pediatric setting, overprescribing of antibiotics contributes to the rise of multidrug-resistant organisms. Antimicrobial stewardship programs (ASPs) are recommended to optimize antibiotic use and combat resistance. However, the implementation of ASPs in low- and middle-income countries faces several challenges. This study aimed to evaluate the implementation process of a multifaceted ASP in 2 pediatric hospitals in Argentina. A qualitative study was conducted in two large public children's hospitals in Argentina, using semistructured interviews with 32 healthcare providers at the beginning and end of the ASP implementation. The study was guided by the normalization process theory. The intervention faced challenges, including limited understanding of its objectives, confusion with existing practices, and insufficient commitment from senior staff. Although junior staff were more receptive, communication barriers with external staff and workload concerns hindered broader adoption. Infectious disease specialists primarily led implementation, with limited involvement of other staff, particularly in training activities. Despite these challenges, participants reported improvements, such as the development of standardized antibiotic guidelines, better interdisciplinary collaboration, and improved communication. However, organizational support and resistance to new practices remained barriers. This study highlights the importance of organizational context and staff commitment in ASP implementation. Tailored strategies that address the specific challenges of low- and middle-income countries are needed to effectively implement ASPs.

The economic burden of post-endoscopic retrograde cholangiopancreatography (ERCP) procedure infections in Italy

Introduction: The infections of multidrug-resistant organisms (MDROs) associated with duodenoscopes during endoscopic retrograde cholangiopancreatography (ERCP) procedure have become a significant cause for concern, especially in fragile patients. While the clinical impacts of these infections are well-documented, their economic implications remain underexplored. This study assesses the incidence and economic burden of post-ERCP infections in Italy using an administrative database. Methods: We conducted a retrospective observational study using administrative databases from A.O.U. Città della Salute e della Scienza di Torino. The study included all patients who underwent their first inpatient ERCP between 2018 and 2021. Infections were identified using ICD-9-CM codes for Pseudomonas aeruginosa, Clostridium difficile, Escherichia coli, Klebsiella spp., and Staphylococcus aureus. A 1-year follow-up was defined in order to estimate healthcare resource utilization and related costs, including readmissions, drug prescriptions, and outpatient specialist and laboratory services. Results: The study included 686 inpatient ERCP cases, an overall infection rate of 4.2% was observed. Higher infection rates were observed in women (4.6%), patients over 70 years old (4.6%), emergency admissions (5.1%), and transplant patients (19.1%). The average hospital stay doubled for infected patients (24.3 vs. 11.3 days; p=0.001). Post-ERCP infections led to a 28% increase in average costs (€12,256 vs. €9,561; p=0.048). With an annual volume of 25,000 ERCP procedures, post-ERCP infections in Italy contribute approximately €2.9 million in additional direct costs per year. Conclusion: Post-ERCP infections impose substantial financial burdens on the healthcare system, underscoring the critical importance of implementing cost-effective prevention strategies to mitigate this public health threat in Italy.

Antibiotic treatment of ceftriaxone-susceptible Serratia marcescens bacteremia: A multicenter, retrospective cohort study.

Serratia marcescens has recently been categorized as low-risk for AmpC β-lactamase inducible production, but research on outcomes in Serratia bacteremia by antibiotic choice is limited. This study examined the clinical characteristics and outcomes of patients with ceftriaxone-susceptible Serratia bacteremia who received AmpC-directed β-lactam therapy vs. narrower spectrum therapies. Records of hospitalized adults with at least one positive blood culture for Serratia, over an 8-year period, across seven hospitals in an integrated health care system, were reviewed. Of the 73 identified patients, 17 (23.3%) received carbapenem-based therapy. More than half of cases were community-acquired, with urological and intravenous drug use being the most common sources. While there was a trend toward lower mortality in carbapenem-treated patients (14.8 vs. 0%; p=0.10), this was not statistically significant. The composite outcome of clinical failure was also not significant. However, compared to non-carbapenem-treated patients, carbapenem-treated patients had longer treatment duration (13 vs. 15 days; p=0.02), prolonged hospital stays (5 vs. 11 days; p<0.001), and higher infection-related readmission rates (17.6 vs. 3.6%; p=0.04). A subset analysis of the 56 non-carbapenem treated patients found no significant difference in 30-day mortality or clinical failure between cefepime and non-cefepime-containing subgroups. Our study found that cefepime- or carbapenem-based therapy may have limited clinical relevance in the treatment of Serratia bacteremia when the strains are initially susceptible to ceftriaxone, highlighting the importance of antibiotic stewardship to prevent emergence of multidrug resistant organisms.

Evaluation of invitro antimicrobial activity of Nauclea latifolia root extracts against multi-drug resistant bacterial isolates from diabetic foot ulcers

Background: Infections caused by multi-drug resistant organisms (MDROs) are becoming global health crisis especially the extended-spectrum beta-lactamase (ESBL) producing microbes. The trend in the occurrence of MDROs has been considered by the World Health Organization as critical and urgent need facing medical science. Herbal plants containing phytochemicals that can be synthesized into new antimicrobial agents are potential alternatives for therapy of MDROs. Methodology: Fresh roots of Nauclea latifolia were harvested from the shrub and identified by botanist at the Nnamdi Azikiwe University with specimen number NAUH-215A. The roots were washed, chopped into smaller sizes for easy drying, air dried under shade and pulverized using a milling machine. The pulverized plant root was extracted using methanol, hexane, ethyl-acetate, and aqueous extraction. Wound swabs were collected from diabetic patients with foot ulcers and processed using conventional culture isolation and biochemical identification test scheme for bacterial isolates that were used as test organisms. Antimicrobial susceptibility test (AST) was performed by the Kirby-Bauer disc diffusion technique and multi-drug resistance (MDR) was determined for each isolate. The phytochemical composition of the plant extracts was assessed using standard methods. Antibacterial activities of the methanol root extracts and the fractions were determined at a concentration of 400mg/ml using agar well diffusion method in triplicate and the mean zone diameter of inhibition measured. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of the methanol root extracts and the fractions were determined using the serial doubling dilution technique. The time-kill assay was also evaluated. Results: The root extract yield of N. latifolia indicated that methanol extract produced a higher yield of 12.8%, followed by ethyl acetate root fraction at 8.0%, hexane fraction at 7.6%, and aqueous extract produced the least yield at 6.8%. The phytochemical analysis showed that methanol root extracts contain various phytochemicals which included phenols, flavonoids, tannins, glycosides, alkaloids, saponins, terpenoids, and triterpenes. The methanol root extract produced a higher mean inhibition zone diameter of 25.0±00mm against Escherichia coli, followed by mean inhibition zone diameter of 23.0±1.0mm against Klebsiella pneumoniae, 20.0±2.0mm against Staphylococcus aureus and Streptococcus pneumoniae, and the least mean inhibition zone diameter of 18.7±1.2mm against Pseudomonas aeruginosa. The MIC of the methanol root extracts for N. latifolia ranged from 3.125 to 12.5mg/ml, and MBC ranged from 6.25 to 25.00 mg/ml. The time-kill assay of methanol extract at 1x MIC, 2x MIC, and 3x MIC showed that reduction in the viable cell count of the initial inoculum was observed within 2-8 hours of incubation at 37oC, indicating high activity. Conclusion: The methanol root extracts of N. latifolia could be a potential source of antibacterial agent, which can complement conventional antibiotics currently used in the treatment of infections caused by MDR bacterial isolates.

The role of antibiotics in the treatment of bacterial infections: A literature review

Bacterial infections continue to be a major public health challenge due to the large number of potential pathogens and varying disease states from mild or asymptomatic to life-threatening conditions. The increasing threat of antibiotic resistance poses significant challenges in the treatment of bacterial infections, primarily stemming from the misuse and overuse of antibiotics. The emergence of multidrug resistant organisms such as Acinetobacter baumannii, which compromises the arsenal of treatment options that healthcare providers have to manage diseases, has led to the development of increased resistance in microbes; therefore, appropriate policies need to be implemented to combat antibiotic resistance and ensuring effective treatment. A comprehensive understanding of these evolving treatment modalities, alongside stringent adherence to prescribing guidelines, is crucial for overcoming the current antibiotic crisis and improving patient care.

Ceftazidime-avibactam for the treatment of febrile neutropenia in HSCT recipients and acute leukemia patients post induction chemotherapy

Febrile neutropenia is a major complication in patients with acute leukemia or those undergoing hematopoietic stem cell transplantation (HSCT). Understanding patient characteristics and susceptibility patterns in febrile neutropenia is essential for appropriate antimicrobial therapy. First-line agents should have Pseudomonas aeruginosa coverage, but with the increase in multi-drug resistant organisms, ceftazidime-avibactam has emerged as a new therapeutic option. This retrospective case–control study included 300 admissions (143 patients) between January 2009 and December 2022. Patients with hematologic neoplasms and patients that underwent HSCT, satisfying the criteria of febrile neutropenia and treated with ceftazidime-avibactam (CAZAVI) were included and compared to controls who received the best available therapy (BAT). A bivariate regression model explored independent predictors of septic shock and mortality. Patients who received CAZAVI were more likely to have a microbiologically documented infection (59.0% vs. 28.3%). Complications were significantly more frequent in the CAZAVI group, with sepsis being the most common (59.0%). Multivariable logistic regression analysis showed that receiving CAZAVI was an independent risk factor for both sepsis and mortality (aOR 6.33 [95% CI 2.81–14.30] and 7.82 [2.63–23.26], respectively). Knowing common organisms and patterns of resistance, with an understanding of risk factors for morbidity and mortality, is crucial for the antimicrobial management of febrile neutropenia. Further studies on the effectiveness of CAZAVI in this population are needed.

Synergistic effect of (Azadirachta indica) Neem extract on multi drug-resistant gram-negative isolates from clinical samples at a tertiary care center

The indiscriminate usage of antibiotics in treatment and animal feed has led to the development of pan and multi drug resistance. The developing resistance in addition to the mortality had skewed the minds of researchers in search of newer antimicrobial agents. Among the native plants, one with potent antibacterial activity is Neem (Azadirachta indica). The leaves, bark, flowers, fruits, seed, and gum of the neem tree are utilised for various beneficial effects. The clinical samples including pus, urine, aspirate, sputum was sent to the microbiology department. The Gram negative Multi drug resistant organisms were included in the study. Around 210 isolates were obtained during the study period out of which 66 (31.4%) isolates were MDR. The synergistic effect of Neem extract was evaluated which showed a significant change in the susceptibility as intermediate range to susceptible range, resistant to intermediate and resistant to sensitive. The Neem extract has better antibacterial effect however, multicentric studies must be carried out to identify the minimum inhibitory concentration against various isolates.

The Prevalence of Multidrug Resistance in Enterobacterales Is Higher in Patients Undergoing Hematopoietic Stem Cell Transplantation

Abstract Background Antimicrobial resistance is a global public health emergency. Patients undergoing hematopoietic stem cell transplantation (HCT) are at increased risk for severe infections with multidrug-resistant (MDR) organisms, although more data are needed on the relative burden of MDR Enterobacterales (MDR-E) in immunocompromised populations. In this study, we compare the prevalence of Enterobacterales resistance in cultures from patients undergoing HCT with that of non-HCT patients seeking care at a large healthcare system in North Carolina, USA. Methods We analyzed electronic health data from 52 067 patients aged ≥18 years with a culture positive for Enterobacterales species (2000–2023). Of these, 271 had undergone HCT prior to culture-recovered Enterobacterales. We compared resistance trends over time for specific antibacterial classes using a 5-year moving average and used generalized linear models to estimate prevalence ratios and differences of MDR-E in HCT versus non-HCT patients. Results HCT recipients overall had a higher prevalence of MDR-E (37.7% vs 19.4%) and resistance for all individual antibiotic classes analyzed. Comparing HCT vs non-HCT groups, the highest prevalence ratio was observed for resistance to aminoglycosides (2.10 [95% confidence interval {CI}, 1.65–2.68]); the largest adjusted absolute difference in nonsusceptibility was observed with quinolones (20.4 [95% CI, 14.9–25.8]). MDR-E infections were associated with double all-cause mortality at 1 year. Conclusions This large longitudinal study highlights how antimicrobial resistance has consistently been a substantial problem in HCT recipients over the prior 2 decades. Targeting antimicrobial resistance mitigation efforts will be key in reducing the risk of MDR infections in HCT.

Pathogenic Burden, Antimicrobial Resistance Pattern and Clinical Outcome of Nosocomial Bloodstream Infections in Intensive Care Unit.

Purpose: Nosocomial bloodstream infections with multidrug-resistant microorganisms have become a common health threat in intensive care settings worldwide. Understanding antimicrobial resistance and the outcomes of these infections is crucial for addressing this issue. This study aimed to investigate the burden, antimicrobial resistance, and 28-day outcomes of nosocomial bloodstream infections in the intensive care unit. Materials and Methods: This retrospective study was conducted in a multispecialty intensive care unit at a tertiary care hospital in western India. Adult patients aged ≥18 years with bloodstream infections acquired after 48 h of admission were included in the analysis. Results: A total of 245 patients suspected of having nosocomial infections in the intensive care unit were evaluated, and 179 were included in the study. Gram-negative bacteremia was identified in the majority of cases, affecting 111 (62%) patients. Carbapenem-resistant Acinetobacter baumannii was the most prevalent pathogen, found in 21.2% (38/179) of patients. Candida species were detected in 37 (20.6%) cases, and gram-positive cocci were identified in 31 (17.3%) patients, with vancomycin-sensitive Enterococci being the most common gram-positive cocci isolated from blood. The central venous catheter was the most frequent source of bloodstream infection, identified in 66 (36.9%) patients. Among all patients, 28-day mortality was observed in 102 (57%) patients. Higher quick sepsis-related organ failure (qSOFA) scores at the onset of bloodstream infection, central venous catheters as a source of infection, inability to initiate early appropriate therapy and septic shock at the onset of bloodstream infection were identified as independent predictors of mortality in patients with nosocomial bloodstream infections. Conclusion: An increased burden of gram-negative bacilli and Candida was found to cause nosocomial bloodstream infections, with very high rates of antimicrobial resistance. Early appropriate diagnosis and treatment play a critical role in improving survival. Additionally, enhanced infection prevention and control practices are necessary to mitigate the heavy burden of infections caused by multidrug-resistant organisms in critical care settings.

Diverse polysaccharide production and biofilm formation abilities of clinical Klebsiella pneumoniae

Klebsiella pneumoniae infections have become a growing threat for human health. The lack of understanding of the relationship between antibiotic resistance, mucoviscosity, and biofilm formation impedes our abilities to effectively predict K. pneumoniae infection outcomes. The Multidrug-Resistant Organism Repository and Surveillance Network offers a unique opportunity into the genetic and phenotypic variabilities in the K. pneumoniae isolates. To this end, we compared the genetic profiles of these isolates with the phenotypic biofilm formation, percent mucoviscosity, and growth rates. There was a significant phenotype-genotype correlation with decreased biofilm formation and an insertion sequence in the transcriptional activator of the type III fimbrial system. Interestingly, the most mucoid strains in the populations were lacking the genetic element regulating the mucoid phenotype and three of these isolates were able to form robust biofilms. The combination of phenotypic, genomic, and image analyses revealed an intricate relation between growth, mucoviscosity and specific virulence-associated genetic determinants.

Identifying multidrug-resistant organisms in diabetic foot ulcers: a study of risk factors and antimicrobial resistance genes.

This study aims to evaluate the antibiotic susceptibility profiles of bacterial isolates from DFU patients, identify the prevalence of MDROs, and identify specific risk factors contributing to these infections to inform effective antibiotic treatment strategies. This prospective cohort study included 187 DFU patients from March 2023 to February 2024 at King Khalid Hospital, Saudi Arabia. The exclusion criteria were nondiabetic ulcers, specific infections, tumours, or recent antibiotic use. Data on demographics, diabetes duration, DFU characteristics, and antibiotic history were collected. Ethical approval and informed consent were obtained. During the 1-year study, 187 DFU patients were included, with 72.7% males and 27.3% females. The mean age of the study participants was 54.9 ± 11.8 years. The average duration of diabetes was 6.3 ± 3.7 years, and themean HbA1c was 8.0 ± 1.0%. Over half (54.5%) of the patients had Wagner ulcer grade III, and neuropathy (67%) and retinopathy (73%) were the most common complications. Polymicrobial infections were identified in 54% of the cases, with 61.5% of the isolates producing biofilms. The key risk factors for MDR infections included amputation (OR: 5.92), polymicrobial infections (OR: 7.49), biofilm production (OR: 5.00), recent antibiotic use (OR: 3.97), and an ulcer duration > 30 days (OR: 2.23). Sex, age, and weight were not significantly associated with MDR infections. Among the 27 MRSA isolates, 81.5% carried the mecA gene, and 98.8% of the ESBL-producing organisms harboured at least one ESBL gene, with blaCTX-M being the most common (27.2%). Carbapenem resistance was confirmed in 25.6% of the isolates, with blaNDM being the predominant carbapenemase gene (69.3%). Coresistance with ESBL genes was detected in 66.7% of the blaNDM-producing isolates. This study demonstrates a high prevalence of MDROs in DFUs, primarily driven by biofilm-producing polymicrobial infections and resistance genes like blaNDM and blaCTX-M. The findings accentuate the clinical importance of integrating molecular diagnostics for early detection of resistance determinants, enabling precise, targeted therapy. Tailored antibiotic stewardship and enhanced infection control measures are critical to optimizing treatment outcomes, reducing complications, and mitigating the burden of chronic DFUs in healthcare settings.

Application of metagenomic next-generation sequencing in pathogen detection for patients with lower respiratory tract infections caused bymultidrug-resistant organisms and analysis ofrelated factors.

The incidence of lower respiratory tract infections (LRTIs) caused by multidrug-resistant organisms (MDRO) has been high in recent years. However, traditional etiological detection methods have not been able to meet the needs for clinical diagnosis and prognosis of LRTIs. The rapid development of metagenomic next-generation sequencing (mNGS) provides new insights for diagnosis and treatment ofLRTIs. We conducted a retrospective study on 95 patients with lower respiratory tract infections caused by MDRO admitted to our respiratory department from January 2022 to December 2023. Thesepatients underwent mNGS testing and conventional culture testing. Additionally, 150 patients without lower respiratory tract infections caused by MDRO during the same period were included as thenon-MDRO group. General information was collected, and Logistic regression analysis was performed to identify risk factors for MDRO infections in patients with lower respiratory tract infections. Our results show that the time to pathogen detection by mNGS was 50.76 ± 1.730 h, that is significantly shorter than 55.53 ± 2.782 h required for conventional culture testing. The pathogen detection rate by mNGS was 89.47% (85/95), higher than the 67.37% (64/95) identified by conventional testing. In terms of pathogen genus distribution, mNGS detected a total of 279 pathogens, while conventional testing detected 121 pathogens. Logistic multivariate regression analysis identified that the use of more thantwo antibiotics, invasive procedures, invasive mechanical ventilation for ≥7 days, and stay in therespiratory intensive care unit (RICU) for ≥7 days were the main influencing factors for lower respiratory tract infections caused by MDRO (P < 0.05).

Antimicrobial Susceptibility Pattern of Community Isolates of Urinary Tract Infection in Bangladesh

Background: Overuses and injudicious uses of maximum antibiotics that have been prescribed empirically in community acquired UTI are being the prime cause of increasing resistance pattern among uropathogens in Bangladesh. There are minimum reports on antimicrobial resistance pattern among uropathogens in different regions of Bangladesh. No reports have been carried out to determine the response of uropathogens to fosfomycin yet in our country. So, the study aimed to determine the prevalence of uropathogens causing UTI in community and to determine the increasing resistance pattern among them with special emphasis on their ciprofloxacin and fosfomycin resistance status. Methodology: Identification of isolated bacteria was performed from collected 187 culture positive cases. Their antimicrobial resistance pattern was determined by Kriby- Bauer modified disc diffusion test. Minimum inhibitory concentration test of ciprofloxacin was performed among the ciprofloxacin resistant bacteria by agar dilution method. Result: The study demonstrated a higher prevalence of UTI in female (70.1%) than in male (29.9%). The most common isolated bacteria was E. coli (80.2%) followed by Klebsiellaspp. Higher resistance rate of 171 Enterobacteriaceae to ampicillin and 3rd generation cephalosporins was observed 71.9% and 49.1%-59.7% respectively in all 6 districts of Bangladesh. Ciprofloxacin resistance has been found higher 43.9% and 50%among Enterobacteriaceae and Staphylococcus spp. More than 50% of ciprofloxacin resistant bacteria had MIC 64ug/ml. All the strains of Enterobacteriaceae were sensitive to fosfomycin except 20% Klebsiella. Conclusion: Rising antimicrobial resistance pattern among uropathogens in different districts provide physicians an important information to make a discreet choice of antibiotics in empiric therapy of community acquired UTI in Bangladesh to reduce further evolution of multidrug resistant organisms. Central Medical College Journal Vol 8 No 1 January 2024 Page: 38-46

Electronic Sepsis Screening Among Patients Admitted to Hospital Wards

Sepsis screening is recommended among hospitalized patients but is supported by limited evidence of effectiveness. To evaluate the effect of electronic sepsis screening, compared with no screening, on mortality among hospitalized ward patients. In a stepped-wedge, cluster randomized trial at 5 hospitals in Saudi Arabia, 45 wards (clusters) were randomized into 9 sequences, 5 wards each, to have sepsis screening implemented at 2-month periods. The study was conducted between October 1, 2019, and July 31, 2021, with follow-up through October 29, 2021. An electronic alert, based on the quick Sequential Organ Failure Assessment score, was implemented in the electronic medical record in a silent mode that was activated to a revealed mode for sepsis screening. The primary outcome was 90-day in-hospital mortality. There were 11 secondary outcomes, including code blue activation, vasopressor therapy, incident kidney replacement therapy, multidrug-resistant organisms, and Clostridioides difficile. Among 60 055 patients, 29 442 were in the screening group and 30 613 in the no screening group. They had a median age of 59 years (IQR, 39-68), and 30 596 were male (51.0%). Alerts occurred in 4299 of 29 442 patients (14.6%) in the screening group and 5394 of 30 613 (17.6%) in the no screening group. Within 12 hours of the alert, patients in the screening group were more likely to have serum lactate tested (adjusted relative risk [aRR], 1.30; 95% CI, 1.16-1.45) and intravenous fluid ordered (aRR, 2.17; 95% CI, 1.92-2.46) compared with those in the no screening group. In the primary outcome analysis, electronic screening resulted in lower 90-day in-hospital mortality (aRR, 0.85; 95% CI, 0.77-0.93; P < .001). Screening reduced vasopressor therapy and multidrug-resistant organisms but increased code blue activation, incident kidney replacement therapy, and C difficile. Among hospitalized ward patients, electronic sepsis screening compared with no screening resulted in significantly lower in-hospital 90-day mortality. ClinicalTrials.gov Identifier: NCT04078594.