Multidrug-resistant Organisms Research Articles

Emergence of resistance to last-resort antimicrobials in bacteremia patients: A multicenter analysis of bloodstream pathogens in Korea.

This study retrospectively reviewed the microbiological and clinical characteristics of patients diagnosed with bacteremia. Results from the first positive blood cultures were consecutively collected from July 2022 to June 2023 at a public secondary hospital, a university-affiliated tertiary hospital, and a university-affiliated secondary hospital in the Seoul metropolitan area. Antibiotic spectrum coverage (ASC) scores were calculated on the day the blood culture was performed (B0) and on two days after the blood culture results were reported (R+2). A total of 3,397 isolates were collected from 3,094 patients. Among these, 949 isolates obtained from 893 patients were classified as multidrug-resistant organisms (MDRO), including 170 imipenem-resistant gram-negative bacteria, 714 methicillin-resistant staphylococci, and 65 vancomycin-resistant enterococci. Interestingly, 13 and 42 gram-positive isolates were resistant to linezolid and quinupristin/dalfopristin, respectively. Moreover, 44 and 181 gram-negative isolates were resistant to amikacin and tigecycline, respectively. The proportion of ASC scores corresponding to broad or extremely broad-spectrum coverage was not significantly different between MDRO and non-MDRO groups at B0 (p = 0.0925). However, it increased in the MDRO group at R+2 (p <0.001). This study found that resistance to last-resort antimicrobials is emerging. Therefore, developing and incorporating molecular diagnostics using a wide range of resistance targets may facilitate rapid, tailored antimicrobial treatments.

Transmission Routes and Prevention Strategies of Multidrug-Resistant Organism Infections in Hospitals

With the spread of multidrug-resistant organisms (MDROs) in hospitals, infection control faces significant challenges. MDROs refer to microorganisms resistant to three or more antimicrobial agents, commonly including methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), and extended-spectrum β-lactamase-producing bacteria (ESBL). These resistant organisms primarily transmit through direct contact, indirect contact, and airborne routes within hospitals. Effective prevention and control of these infections require a comprehensive approach, including strict hand hygiene and personal protection, implementation of infection control standards, environmental cleaning and disinfection, management of medical device sterilization, and rational use of antimicrobial agents along with resistance monitoring. This paper summarizes the transmission routes and prevention strategies for MDRO infections, providing references for hospital management and clinical practice. Future research should focus on optimizing prevention measures and resistance monitoring to address the changing patterns of resistant organisms and enhance infection control effectiveness.

EFFECT of daily antiseptic bathing with octenidine on ICU-acquired bacteremia and ICU-acquired multidrug-resistant organisms: a multicenter, cluster-randomized, double-blind, placebo-controlled, cross-over study.

Antiseptic bathing has garnered attention in an effort to reduce hospital-acquired infections. Previous studies have shown the efficacy of antiseptic bathing in high-risk environments, such as intensive care units (ICUs), using chlorhexidine. In this study we aimed to evaluate the effectiveness of octenidine as a potential alternative due to its established popularity and widespread use in Europe. We compared the rates of ICU-acquired primary bacteremia and ICU-acquired multidrug-resistant organisms (MDROs) in a multicenter, cluster-randomized, double-blind, placebo-controlled, cross-over study using octenidine-impregnated and placebo washcloths. On 44 ICUs in 23 hospitals throughout Germany, we compared individual ICUs with themselves over two 12-month time periods. All data were obtained digitally via hospital information systems as individual ward-movement data and microbiological test results; both endpoints were algorithmically derived. 104,039 ICU episodes from 93,438 patients with 712,784 microbiological test results were analyzed, thereby detecting 1508 cases of ICU-acquired primary bacteremia and 1871 cases of ICU-acquired MDRO. Bathing with octenidine-impregnated washcloths prevented ICU-acquired primary bacteremia; a risk reduction of 17% was seen homogeneously across all participating ICUs (adjusted hazard ratio (HR) 0.83, 95% confidence interval (CI) [0.75; 0.92], p = 0.0003). This reduction affected predominantly coagulase-negative staphylococci (53%) and enterococci (17%). However, no intervention effect was seen for ICU-acquired MDROs (adjusted HR 0.98, 95% CI [0.83; 1.15]). Heterogeneity among intra-ICU intervention effects on MDRO acquisition was substantial. Antiseptic bathing with octenidine may be effective in preventing ICU-acquired primary bacteremia, particularly due to Gram-positive bacteria and common skin commensals.

Corynebacterium striatum

Abstract Corynebacterium striatum (C. striatum) is a rapidly emerging multidrug-resistant organism commonly found as a skin and respiratory tract commensal. The first case of C. striatum infection was published in 1980 in a patient with chronic lymphocytic leukemia who had a pleuropulmonary infection. The chemotherapeutic agents used in hematologic malignancies completely deplete neutrophils, making them susceptible to various pathogens such as C. striatum, which are rarely pathogenic. The spectrum of presentation due to C. striatum includes severe bloodstream infections, pneumonia, meningitis, and infective endocarditis. Some of the most common risk factors are prolonged neutropenia with various invasive devices and numerous prophylactic antibiotics. This article aims to present three cases of C. striatum infections in immunocompromised patients at H. Lee Moffitt Cancer Centre. In such rare cases, infection prevention and appropriate antibiotic coverage are the key to preventing such infections.

Risk of invasive MDRO infection in MDRO-colonized patients.

In this study, we aim to estimate the risk of developing clinical multidrug-resistant organism (MDRO) infection with carbapenem-resistant Enterobacterales (CRE), methicillin-resistant Staphylococcus aureus (MRSA), or vancomycin-resistant enterococci (VRE) in colonized patients compared with non-colonized admitted to high-risk areas with a main focus on CRE colonization/infection. Retrospective cohort study conducted at a tertiary care facility. This study included patients enrolled in active surveillance testing (AST) for CRE, MRSA, or VRE during the year 2021. Development of relevant invasive infection within 365 days of the AST result was collected as the primary outcome. The association between MDRO colonization and infection was calculated using the risk ratio. The prevalence of CRE organisms and carbapenemase genes is presented. A total of 19,134 ASTs were included in the analysis (4,919 CRE AST, 8,303 MRSA AST, and 5,912 VRE AST). Patient demographics were similar between colonized and non-colonized groups. Colonization was associated with an increased risk of infection in the 3 cohorts (CRE, MRSA, and VRE), with risk ratios reported as 4.6, 8.2, and 22, respectively. Most patients (88%) develop CRE infection with the same colonizing carbapenemase gene. Oxa-48/NDM Klebsiella pneumoniae was the most common organism detected in CRE infection. The study demonstrated that colonization with CRE, MRSA, or VRE is a risk factor for developing infections caused by the respective bacteria. The high percentage of match between carbapenemase genes detected in colonization and infection indicates that screening results might be used to inform infection management and treatment.

Surgical Site Infections: Risk Factors for Multiple Antibiotic Resistance in Abdominal Surgery

INTRODUCTION. Multidrug-resistant (MDR) organisms are increasingly becoming a major surgical site infection (SSI); however, the clinical outcomes and risk factors associated with resistant pathogens in general surgery remain poorly understood.THE AIM of the present research is to study the risk factors and consequences of infections in patients with SSI caused by antibiotic resistant pathogens with MDR.MATERIAL AND METHODS. A single-center, retrospective case-control study was carried out. The results of the examination and treatment of 50 patients with SSI + MDR, who made up the main group, and two control groups — non-MDR SSI and no SSI, 50 patients each, were analyzed. A total of 38 risk factors were used: pre- and surgical criteria, clinical, biochemical, instrumental data, postoperative complications and treatment features. The microbial landscape was studied in SSI+MDR. Single- and multivariate analysis was carried out, binary and multinomial logistic regression was performed. P-values &lt;0.05 were considered significant at 95% CI.RESULTS. Significant risk factors were as follows: previous hospitalization, previous antibiotic therapy, terms of preoperative stay of the patient in the department, emergency surgery, class of surgery, decrease in the ratio of ALP/ ALPI, MEI and EMFC (p&lt;0.01); elevated ASA score, obesity, low levels of plasma proteins and albumin, (p&lt;0.05). Among the pathogens, there were more gram-negative enterobacteria (61%) than gram-positive ones (30.5%). Escherichia coli (36.3%) was the most commonly found bacterium, followed by Enterococcus faecium (9.09%), Morganella morganii (7.58%), Staphylococcus aureus (6%), and Pseudomonas aeruginosa (6%). In SSSI, Staphylococcus spp. prevailed. (&gt;80%); in DSSI — Echerichia, Acinetobacter (&gt;70%); and in OSSSI — Enterobacter spp., Acinetobacter and Citrobacter (&gt;90%). SSI+MDR were characterized by serious surgical complications (Clavien Dindo Classification grade 3–5), wound dehiscences and OSSSI, reoperations (p&lt;0.05).CONCLUSION. 1. The primary risk factors for multiple antibiotic resistance were as follows: previous hospitalization, previous antibiotic therapy, the duration of the patient’s preoperative stay in the department, emergency surgery, surgery class, reduced ALP/ALPI ratio, MEI and EMFC. In addition to the above, the following were also of great importance: increased ASA score, obesity, low plasma proteins, albumin.2. When identifying risk factors for multiple antibiotic resistance in surgical patients, the development of severe postoperative complications, sepsis and multiple organ failure can be predicted.3. Perioperative medical and preventive measures require a multidisciplinary approach involving the microbiologist, pharmacologist, immunologist, nutrition specialist, and other expert consultants.

Males are at higher risk of colonization and infection with multi-drug-resistant organisms than females

Global rise of multidrug-resistant organisms (MDRO) is alarming and antimicrobial resistance (AMR) poses a significant public health threat globally. Although certain risk factors are known including recent antimicrobial therapy, inappropriate use and hospitalization, the focus on gender-specific aspects in MDRO is scarce. Our aim was to show gender-specific differences in colonization and infections of multiple MDRO and their detection sites. For this multicentre, retrospective cohort study surveillance data between 2015 and 2020 was collected in 86 hospitals of the Helios group, Germany. The following multidrug-resistant bacteria were analysed according to sample site: MRSA, Enterococcus spp., Escherichia coli, Klebsiella pneumonia, Pseudomonas aeruginosa and Acinetobacter baumannii. Out of the 7,081,708 cases in the database, 187,656 patients were found to be colonized with MDRO (2.65%). A documented infection with MDRO was identified in 33,023 patients (0.466%), with the origin of infection known in 24,231 cases. Male gender was a risk factor for both infection and colonization of any MDRO (p< .001). Males exhibited a higher likelihood of MDRO detection in superficial skin/soft tissue, blood cultures (p < .001), and respiratory samples (p = .002). Additionally, gender-specific differences in MDRO detection site and pathogens were found with slightly higher proportion of MRSA infection in deep skin/soft tissue and respiratory samples for females. Our study reinforces the existing hypothesis that male gender is a risk factor for MDRO, supported by our large dataset. It highlights the need to acknowledge gender-specific MDRO susceptibility in clinical practice.

High Mortality Rates and Antimicrobial Resistance in Children with Invasive Bacterial Infections in a Tertiary Care Facility in West Africa

Abstract Background Childhood data on infection mortality and antimicrobial resistance in Sub-Saharan Africa are emerging but remain limited. The University of Maryland Center for Vaccine Development (CVD) and CVD-Mali have been conducting a prospective observational study at L’Hopital Gabriel Toure (HGT), a referral hospital in Bamako, Mali, since 2002 to identify causes of invasive bacterial infections (IBI) in children. These data have been used to initiate vaccination programs to decrease the burden of Haemophilus influenzae type b and Streptococcus pneumoniae. Additional demographic and antimicrobial susceptibility data have been collected since 2021, allowing for more detailed resistance and mortality analyses. Methods All children presenting to HGT are screened. Children ages 0-15 years with temperature of at least 39 degrees Celsius and/or suspicion of IBI are eligible. Eligible children have blood cultures collected with additional site-specific cultures when focal infection is suspected. Cultures are performed using the Bactec system; when positive, Gram staining, sub-culturing, and antimicrobial susceptibility testing (by disk diffusion using standard methods) are performed. Organisms thought to be contaminants are excluded. American type culture collection strains are utilized for quality control. Results Between 1/14/2021 and 9/14/2023, 28703 patients were screened. 2156 patients were included. 212 patients (10%) had 235 pathogens isolated. Gram positive organisms were most frequently isolated (N=112), followed by Gram negative Enterobacterales (N=81), non-Enterobacterales Gram negatives (N=36), and yeast (N=6). Staphylococcus aureus was the most frequently isolated Gram positive organism (59 bloodstream isolates, 2 joint isolates, 2 subcutaneous isolates) followed by S.pneumoniae (10 bloodstream isolates, 17 cerebrospinal fluid isolates, 1 joint isolate) and Enterococcus species (16 bloodstream isolates). Klebsiella pneumoniae (28 bloodstream isolates, 2 cerebrospinal fluid isolates) and Escherichia coli (18 bloodstream isolates, 3 cerebrospinal fluid isolates, 2 subcutaneous isolates) were the most frequently isolated Gram negative Enterobacterales, with Pseudomonas species most common among non-Enterobacterales Gram negative organisms (16 bloodstream isolates, 1 cerebrospinal fluid isolate). Mortality rates in both culture-positive and culture-negative patients were high (52% and 28%, respectively), with greater than 50% of deaths occurring within 48 hours in both groups. 88% of Gram negative Enterobacterales were ceftriaxone resistant or intermediate, with 56% ciprofloxacin resistant or intermediate; 55% of isolates were resistant or intermediate to both. 71% of isolates were gentamicin resistant. Imipenem resistance remained low, with 91% of isolates retaining sensitivity. 24% of S. aureus isolates were oxacillin resistant and 34% of isolates were resistant or intermediate to trimethoprim/sulfamethoxazole. 100% of S. aureus isolates tested (14/60) retained sensitivity to clindamycin. Only 54% of pneumococcal isolates had positive oxacillin screens, implying frequent penicillin resistance, and only 60% of enterococcal species were ampicillin sensitive, although 92% retained vancomycin sensitivity. Conclusion We found higher mortality rates in our study than in similar studies; the contribution of issues such as limited access to advanced supportive care and delay in presentation is an area for further study. The high frequency of multidrug-resistant organisms is alarming, suggesting an urgent need to investigate underlying contributing factors, increase access to affordable broad-spectrum antibiotics, and create robust antimicrobial stewardship programs.

Comparative Properties of Helical and Linear Amphipathicity of Peptides Composed of Arginine, Tryptophan, and Valine.

The persistence of antibiotic resistance has incited a strong interest in the discovery of agents with novel antimicrobial mechanisms. The direct killing of multidrug-resistant bacteria by cationic antimicrobial peptides (AMPs) underscores their importance in the fight against infections associated with antibiotic resistance. Despite a vast body of AMP literature demonstrating a plurality in structural classes, AMP engineering has been largely skewed toward peptides with idealized amphipathic helices (H-amphipathic). In contrast to helical amphipathicity, we designed a series of peptides that display the amphipathic motifs in the primary structure. We previously developed a rational framework for designing AMP libraries of H-amphipathic peptides consisting of Arg, Trp, and Val (H-RWV, with a confirmed helicity up to 88% in the presence of membrane lipids) tested against the most common MDR organisms. In this study, we re-engineered one of the series of the H-RWV peptides (8, 10, 12, 14, and 16 residues in length) to display the amphipathicity in the primary structure by side-by-side (linear) alignment of the cationic and hydrophobic residues into the 2 separate linear amphipathic (L-amphipathic) motifs. We compared the 2 series of peptides for antibacterial activity, red blood cell (RBC) lysis, killing and membrane-perturbation properties. The L-RWV peptides achieved the highest antibacterial activity at a minimum length of 12 residues (L-RWV12, minimum optimal length or MOL) with the lowest mean MIC of 3-4 µM, whereas the MOL for the H-RWV series was reached at 16 residues (H-RWV16). Overall, H-RWV16 displayed the lowest mean MIC at 2 µM but higher levels of RBC lysis (25-30%), while the L-RWV series displayed minor RBC lytic effects at the test concentrations. Interestingly, when the S. aureus strain SA719 was chosen because of its susceptibility to most of the peptides, none of the L-RWV peptides demonstrated a high level of membrane perturbation determined by propidium iodide incorporation measured by flow cytometry, with <50% PI incorporation for the L-RWV peptides. By contrast, most H-RWV peptides displayed almost up to 100% PI incorporation. The results suggest that membrane perturbation is not the primary killing mechanism of the L-amphipathic RWV peptides, in contrast to the H-RWV peptides. Taken together, the data indicate that both types of amphipathicity may provide different ideal pharmacological properties that deserve further investigation.

Counselling sessions for patients in contact isolation due to multi-drug-resistant organisms improve informedness and reduce dissatisfaction

The spread of multidrug-resistant organisms (MDROs) is a critical health issue. Isolation measures imposed to prevent transmission may result in adverse psychological effects among affected patients. This emphasises the need for better communication and information to improve their hospital experience and mental well-being as well as to prevent inadequate treatment. The present study examines whether tailored counselling sessions during contact isolation can enhance patients' understanding of their situation concerning the significance of their MDRO status and enhance their well-being. A pre-post-intervention study was conducted in a German tertiary care hospital in which N = 64 patients who were isolated due to MDROs received tailored counselling. The counselling included information about MDROs, the reason for hospital isolation measures, and appropriate behaviour during and after hospitalisation. Participants completed questionnaires before and after the counselling sessions to assess its impact on their informedness, patient (dis)satisfaction and well-being measures. Prior to the counselling session, patient dissatisfaction was associated with anxiety and inadequate informedness about MDROs. After the counselling, patients reported a significantly improved comprehension of their MDROs-related situation and a notable decrease in dissatisfaction with their hospital situation, primarily attributed to the acquired information. This is the first German study to show how improved information about MDROs impacts patient satisfaction in hospitals. The findings stress the crucial need for improving healthcare workers' interaction and communication with patients affected by MDROs.

Intensive care unit admission rates and factors associated following Autologous stem cell transplantation-real-world experience from a tertiary center in rural India.

Infectious and other complications can necessitate admission to the intensive care unit (ICU) in autologous stem cell transplantation (ASCT). Data on need for ICU care, impact of various pre- and peri-transplant characteristics on requirement of ICU care and outcomes are scarce from the developing world. A retrospective case record review of ASCT cases was conducted. Pre- and peri-transplant characteristics like infection within 4weeks of transplant, mucositis, surveillance culture positivity, peri-transplant infections, comorbidity, and time to neutrophil and platelet engraftment were noted. A total of 109 patients underwent 109 ASCTs. Most common diagnosis was the plasma cell disorder in 75 (69%) patients. Forty-eight (45%) patients had peri-transplant infections. Fifteen (14%) patients had infections with multi-drug resistant (MDR) organisms. Fifteen (14%) patients required ICU care, the most common reason being hypotension in nine patients (8.3%). Four patients (3.7%) required non-invasive ventilation, and one (0.9%) required invasive ventilation. Mortality rate was 1.8% (two patients). Factors associated with the need for ICU care were time to platelet engraftment (median 15days among those required ICU care versus 13days who did not, p = 0.04) and presence of peri-transplant infection showed a trend toward ICU care need (19% among those required ICU care versus 7% in those who did not, p = 0.05). Delayed platelet engraftment was associated with the need for ICU care and peri-transplant infections were associated with a trend toward need for ICU care.

Synergistic invitro antimicrobial activity of polyherbal combination of Morinda lucida fruit and Pterocarpus santalinoides seed against multi-drug resistant clinical bacterial isolates

Background: Synergistic drug combination has been shown to be a way of bypassing drug resistance and reducing the amounts of antimicrobials consumed. As infections caused by multi-drug resistant organisms (MDROs) continue to pose global threat, it is important to search for new antimicrobial combinations of plant origin that are safe and readily available. The objective of this study is to evaluate the synergistic antimicrobial activity of extracts of Morinda lucida fruit and Pterocarpus santalinoides seed against multi-drug resistant (MDR) bacterial isolates Methodology: Morinda lucida and P. santalinoides fruits were plucked and washed clean, and the fruits of P. santalinoides were deseeded to remove the seeds. They were cut into smaller pieces and dried under shade before being milled into smooth powder and extracted with methanol. The clinical bacterial isolates used were MDR Escherichia coli, Proteus mirabilis, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Staphylococcus aureus. The phytochemical constituents of the extracts were determined using the standard method. The invitro antimicrobial assay of the extracts was done at a concentration of 50 to 400 mg/ml using the agar well diffusion technique. The minimum inhibitory concentration (MIC) and fractional inhibitory concentration (FIC) of each extract were determined using the Checker-board micro-titration method, and the FIC result obtained for each isolate was used to calculate the fractional inhibitory concentration index (FICI) of the combined extracts. The time kill assay was performed to confirm the synergistic and bactericidal activities from the MIC values obtained. Results: The phytochemical analysis revealed that the extracts of both herbal plants contained alkaloids, phenol, tannin, saponin, glycosides, and terpenoids. The antimicrobial assay results showed that the polyherbal combination of the extracts was active against all the MDR bacterial isolates tested with varying zones of inhibition. The mean inhibition zone diameters of individual M. lucida and P. santalinoides ranged from 18.0±0.9mm to 26.0±1.4mm and 17.0±0.1mm to 24.0±0.2mm respectively, while the MIC ranged from 6.25mg/ml to 12.5mg/ml for M. lucida and 12.5 mg/ml for P. santalinoides. The mean inhibition zone diameter of the polyherbal combination of the two plant extracts ranged from 25.00±00mm to 34.0±0.4mm, which compared favorably with that of levofloxacin control (28.0±0.0mm to 32.00±0.0mm), while their MIC ranged from 0.39mg/ml to 1.56mg/ml. The FIC of M. lucida extract ranged from 0.06mg/ml to 0.25mg/ml while that of P. santalinoides ranged from 0.03mg/ml to 0.13mg/ml. The FICI of combined extracts ranged from 0.09mg/ml to 0.38 mg/ml for all the MDR isolates, which is less than 0.5mg/ml, indicating synergism against all the isolates. The time of kill assay confirmed the synergistic and bactericidal activities with a 3log10 CFU/ml decrease in the number of viable cells within 6 hours of incubation.Conclusion: Our findings showed synergistic antibacterial actions of extracts of M. lucida fruit and P. santalinoides seed against MDR clinical bacterial isolates, comparable to levofloxacin. Combination of these herbal plants may serve as alternative sources of antimicrobial agents for the treatment of infections caused by MDR bacterial pathogens.

Gram-Negative Bacteremia: Epidemiology and Antimicrobial Resistance in Qatar

One of the major causes of morbidity and mortality in hospitalised patients is the presence of gram-negative bacteremia (GNB) in blood. The developed resistance among the bacteria poses a significant challenge for treatment. The study aimed to identify the gram-negative patient’s epidemiological risk factors, antimicrobial susceptibility patterns, and clinical outcomes. A retrospective observational study of adult in-patients with gram-negative bacteremia was conducted between January 2019 and December 2020 in the 320-bed general hospital in Qatar. Data on demographics, antimicrobial resistance, source of infection, and treatment were collected. The primary outcomes were patients’ cure, death, or relapse. Total of 357 patients were identified with bacteremia, the most common sources being urinary tract infections (39.6%), intra-abdominal infections (28%), and lower respiratory tract infections (9%). The mean duration of the intravenous and oral antibiotics administration was 14 days. Surgical source control was performed in 35.7% of patients. Common pathogens were Escherichia-coli (47.2%), Klebsiella pneumoniae (16.4%), Salmonella enterica serotype Typhi (10.6%), and Pseudomonas aeruginosa (7.8%). 67.32% fully susceptible strains, 31.56% extended-spectrum beta-lactamase (ESBL) producing bacteria, and 1.11% multidrug-resistant organisms (MDROs) were among the isolates. Most infections (68%) were cured, but 5% had recurrence within 90 days of admission. Infection-related mortality was 8%, and death due to non-infectious causes was 2%. In conclusion, Gram-negative BSIs are severe infections with increasing antimicrobial resistance, primarily caused by ESBL-producing bacteria. High mortality rates are linked to diabetes, age, and hospitalisation, necessitating antibiotic treatment optimisation.

A-288 Active Surveillance Cultures: Frequency of Microorganisms and Phenotypic Resistance Profile From Brazilian Public Hospitals After COVID-19 Pandemic Peak

Abstract Background Surveillance cultures are routinely used by public health authorities to screen for multidrug-resistant bacteria. Recently, the overuse of antibiotics intensified by the COVID-19 pandemic worldwide brought concerns about potential impacts on the acquisition and/or selective pressure of resistance genes, that in general carried by plasmids, which contribute to the rapid resistance spread within specific bacterial populations. The purpose of this study was to determine the prevalence of multidrug-resistant (MDR) organisms recovered from surveillance cultures (rectal, anal, nasal, and axillary) isolated from several Brazilian public hospitals. Methods Surveillance samples were analyzed from 1st January to 31st December 2023. All the swab samples were collected from patients admitted from high-risk settings or transferred from areas with high rates of MDR organisms. All clinical specimens were inoculated onto a selective media (ChromID media, bioMerieux) and incubated at 35±2°C for 18-24 h. The screening test was performed to Gram-negative bacilli (GNB) using the antibiotics ertapenem, imipenem and meropenem and for Gram-positive Cocci (GPC) screening was tested oxacillin (methicillin) and vancomycin using disc diffusion method. Bacteria identification was performed by MALDI-TOF mass spectrometry (Vitek-MS and bioMerieux) and as required, the minimal inhibitory concentrations (MIC) of antibiotics were determined using the Vitek 2 System (bioMerieux). Results A total of 71,064 rectal swab samples were processed. 4,652/71,064 (6.5%) samples showed positive results for the presence of 5.255 MDR microorganisms. Out of which, 4,477/5,255 (85.2%) were Gram-negative Bacilli (GNB) and 778/5,255 (14.8%) were Gram-positive Cocci (GPC). The majority of the isolated carbapenems resistance was Klebsiella spp. [2,791/5,255 (53.1%)], which the Klebsiella pneumoniae was the predominant species, followed by Acinetobacter baumannii [1,268/5,255 (24.1%)], Pseudomonas aeruginosa [263/5,255 (5%)], Enterobacter spp. [96/5255 (1.8%)], Serratia spp. [31/5,255 (0.6%)], Citrobacter spp. [22/5,255 (0.4%)], and others BGN [6/5,255 (0.2%)]. The resistance to vancomycin and methicillin were observed in 10% (525/5,255) of Enterococcus spp. and 4.8% (253/5,255) of Staphylococcus aureus, respectively. Conclusions The study found that K. pneumoniae carbapenem-resistant and Enterococcus spp. vancomycin-resistant were the main Gram-negative and Gram-positive organisms recovered from surveillance culture samples. However, our data draws attention to the increased cases of carbapenem-resistant Acinetobacter baumannii as the second most frequent pathogen isolated from surveillance samples after the last wave of COVID-19 pandemic. Active surveillance culture for target microorganisms followed by contact precautions to minimize the chance of transmitting MDR organisms from colonized to non-colonized patients consist of an important activity of infection control policy.

A-277 Viability of multi-drug resistant organisms in a fecal collection and transport system stored at ultra-low temperature

Abstract Background Epidemiological studies are constantly investigating new, easier ways to collect and store patient specimens that allow for flexible testing windows and long-term storage as well as accurate quantification of organisms of interest. The FecalSwabTM system (Copan, Brescia, Italy) is intended for the collection and preservation of rectal and fecal specimens. This system includes a preservation medium which serves to maintain the viability of enteric pathogens during transport to a clinical laboratory for up to 72 hours at 4oC. The objective of this study was to assess the continued viability of multi-drug resistant organisms (MDROs) suspended in the FecalSwab sample format when frozen at -80°C and the impact of freeze-thaw cycles. Methods A total of 40 organisms were chosen spanning methicillin-resistant Staphylococcus aureus (MRSA, n=10), carbapenem-resistant Pseudomonas aeruginosa (CRPA, n=5), carbapenem-resistant Enterobacterales (CRE, n=5), vancomycin-resistant Enterobacterales (VRE, n=10) and extended-spectrum beta-lactamase containing Enterobacterales (ESBL, n=10). Each organism was spiked into FecalSwab at standardized concentrations. At each time point, FecalSwab media was plated onto blood agar and colonies were quantified. Each of the 40 organisms were assessed one-week post-freeze and over the course of freeze-thaw cycles at days 3 and 5. The survival of each MDRO was evaluated by calculating a difference between the concentration of organisms recovered (CFU per 10uL media) at each time point and the concentration of organisms confirmed present at the time of inoculation. Percent recovery was calculated from this difference. Results One week after freezing, the percent recovery for MRSA, VRE, ESBL, CRE, and CRPA averaged to 102%, 201%, 17.8%, 7.6%, and 0.8%, respectively (Kruskal Wallis p &amp;lt; 0.001), with significant differences noted between gram positive and gram negative organisms (Kruskal Wallis p &amp;lt;0.001). Conclusions Epidemiological studies interested in MDRO surveillance rely on methodologies that allow for accurate quantification of viable organisms. In this study, we’ve evaluated the viability of several multi-drug resistant organisms when frozen at -80°C in the FecalSwab. The FecalSwab system is intended for the collection of rectal swab and fecal specimens and to preserve the viability of enteric pathogenic bacteria for testing in the clinical laboratory. Although it was not specifically designed to preserve MDROs, it performed well with MRSA and VRE, but less well with CRE, CRPA and ESBL organisms. When using the FecalSwab system, the observed gram-specific differences may inform the suitability of this system depending on the organism(s) of interest.

The epidemiology and microbiology of central venous catheter related bloodstream infections among hemodialysis patients in the Philippines: a retrospective cohort study

BackgroundDespite efforts to improve the management of catheter-related bloodstream infections (CRBSI) in literature, temporary CVCs continue to be used for maintenance hemodialysis outside of acute care settings, particularly in the Philippines.MethodsWe conducted a retrospective cohort study to investigate the incidence, outcomes, risk factors, and microbiological patterns of CRBSI among adult kidney disease patients undergoing hemodialysis at the Philippine General Hospital, the country's largest tertiary referral center. We included all adult patients who received a CVC for hemodialysis from January 1, 2018, to August 31, 2019, and followed them for six months to observe the occurrence of CRBSI and its outcomes.ResultsOur study documented a CRBSI incidence rate of 6.72 episodes per 1000 catheter days, with a relapse rate of 5.08%, a reinfection rate of 15.74%, and a mortality rate of 6.09%. On multivariable regression analysis, we identified autoimmune disease, dialysis frequency of > 3 × per week, use of CVC for either blood transfusion or IV medications, renal hypoperfusion, drug-induced nephropathy, and hypertensive kidney disease as significant risk factors for CRBSI. Gram-negative bacteria, including B. cepacia complex, Enterobacter, and Acinetobacter spp, were the most common organisms causing CRBSI. Multidrug-resistant organisms (MDROs) comprised almost half of the isolates (n = 89, 44.5%), with Coagulase-negative Staphylococcus species having the highest proportion among gram-positive organisms and Acinetobacter spp. among gram-negative isolates.ConclusionOur findings emphasize the need for more stringent measures and interventions to prevent the propagation of identified pathogens, such as a review of sterile technique and adequate hygiene practices, continued surveillance, and expedited placement and utilization of long-term access for patients on maintenance hemodialysis. Furthermore, CVC use outside of hemodialysis should be discouraged, and common antibiotic regimens such as piperacillin-tazobactam and fluoroquinolones should be reviewed for their low sensitivity patterns among gram-negative isolates. Addressing these issues can improve hemodialysis patients' outcomes and reduce the CRBSI burden in our institution.

Natural History and Microbiological Profiles of Patients With Acute Pancreatitis With Suspected Infected Pancreatic Necrosis.

Acute pancreatitis (AP) is a prevalent emergency. The clinical spectrum of the condition is varied, ranging from a mild to a malignant course with higher mortality rates. Infection of pancreatic/peri necrosis, extrapancreatic infections, and organ failure are significant complications in AP. In the recent era, microbiological composition has shifted more towards multi-drug-resistant organisms due to irrational antibiotic use. This study aims to understand the natural history of patients with suspected infected pancreatic necrosis (IPN), the prevalence of multi-drug-resistant organisms (MDROs), and their antibiotic susceptibility patterns. This prospective, observational study was performed on 130 cases of acute necrotizing pancreatitis (ANP) with suspected IPN that were evaluated during their period of admission in the department of gastroenterology, emergency medicine, or surgery ward of thePostgraduate Institute of Medical Education and Research, Chandigarh, India, a tertiary hospital. The details of outcomes were recorded. The organisms in cases with IPN and antibiotic resistance patterns of various organisms were studied. The most prevalent site of necrosis was combined pancreatic and peripancreatic tissues in 111 (85.4%) patients. The computed tomography severity index (CTSI) had a mean of 8.72±1.43. Of all participants, 36 (27.7%) patients had <30% necrosis, 47 (36.2%) had 30%-50% necrosis, and 47 (36.2%) had >50% necrosis. Overall, 80 (61.5%) patients had organ failure, with acute lung injury (ALI) being the most common. Rates of complications were markedly greater in cases with higher pancreatic necrosis and with infected necrosis (p<0.05). The most common organism isolated from necrotic tissue was Escherichia coli (E. coli) in 17 (32.07%) cases, followed by Acinetobacter baumannii (A. baumannii) in 12 (22.64%) cases. The most common extrapancreatic infection site was respiratory tract infections. Pseudomonas aeruginosa (P. aeruginosa) and A. baumannii revealed maximum resistance to most of the drugs. Conclusion: Infected pancreatic necrosis is linked to high rates of morbidity and mortality. Our study suggests that irrational usage of antibiotics increases the incidence of combined infection, especially with higher rates of multi-drug-resistant infections.

Interactive hygiene training using free open source software.

Regular hygiene trainings are an important way to refresh and improve knowledge about hygiene measures and the prevention of healthcare-associated infections. We aimed to develop an e-learning course to allow healthcare workers (HCWs) to learn these contents through a self-paced online format. We developed an interactive hygiene training for HCWs of a tertiary care hospital using different content types of the HTML-5 package (H5P) plugin embedded into a Moodle-based learning management system. We evaluated the course using a short online questionnaire. We present various suitable topics for online hygiene trainings as well as their implementation in an e-learning course. Examples include content on hand hygiene indications and techniques, information on multidrug-resistant organisms and other current topics in infection control. HCWs reported high overall satisfaction, perceived increase in knowledge, practical relevance as well as good usability and comprehensibility. Currently available commercial and non-commercial hygiene trainings present a number of specific advantages but also drawbacks. The presented approach combines the advantages of both approaches. The majority of the presented content can be readily adapted to suit various hospitals and care facilities or serve as inspiration for creating similar courses while remaining cost-effective. H5P course presentations are a low-threshold, cost-effective way to implement digital hygiene trainings in a wide variety of clinical settings.

Oral-gut microbiome interactions in advanced cirrhosis: characterisation of pathogenic enterotypes and salivatypes, virulence factors and antimicrobial resistance

Background & AimsCirrhosis complications are often triggered by bacterial infections with multidrug-resistant organisms. Alterations in the gut and oral microbiome in decompensated cirrhosis (DC) influence clinical outcomes. We interrogated: (i) gut and oral microbiome community structures, (ii) virulence factors (VFs) and antimicrobial resistance genes (ARGs) and (iii) oral-gut microbial overlap in patients with differing cirrhosis severity. Methods15 healthy controls (HC), 26 stable cirrhosis (SC), 46 DC, 14 acute-on-chronic liver failure (ACLF) and 14 with severe infection without cirrhosis (NLS) participated. Metagenomic sequencing was undertaken on paired saliva (S) and faecal (F) samples. ‘Salivatypes’ and ‘enterotypes’ based on genera clustering were assessed against cirrhosis severity and clinical parameters. VFs and ARGs were evaluated in oral and gut niches, and distinct resistotypes identified. ResultsSalivatypes and enterotypes revealed a greater proportion of pathobionts with concomitant reduction in autochthonous genera with increasing cirrhosis severity and hyperammonaemia. Increasing overlap between oral and gut microbiome communities was observed in DC and ACLF vs SC and HCs, independent of antimicrobial, beta-blocker and acid suppressant therapies. Two distinct gut microbiome clusters [ENT2/ENT3] harboured genes encoding for the phosphoenolpyruvate:sugar phosphotransferase system (PTS) system and other VFs in DC and ACLF. Substantial ARGs (oral: 1,218 and gut: 672) were detected [575 common to both sites]. The cirrhosis resistome was distinct, with three oral and four gut resistotypes identified, respectively. DiscussionThe degree of oral-gut microbial community overlap, frequency of VFs and ARGs all increment significantly with cirrhosis severity, with progressive dominance of pathobionts and loss of commensals. Despite similar antimicrobial exposure, patients with DC and ACLF have reduced microbial richness compared to NLS, supporting the additive pathobiological effect of cirrhosis. Impact and implicationsThis research underscores the crucial role of microbiome alterations in the progression of cirrhosis in an era of escalating multidrug resistant infections, highlighting the association and potential impact of increased oral-gut microbial overlap, virulence factors, and antimicrobial resistance genes on clinical outcomes. These findings are particularly significant for patients with decompensated cirrhosis and acute-on-chronic liver failure, as they reveal the intricate relationship between microbiome alterations and cirrhosis complications. This is relevant in the context of multidrug-resistant organisms and reduced oral-gut microbial diversity that exacerbate cirrhosis severity, drive hepatic decompensation and complicate treatment. For practical applications, these insights could guide for cirrhosis patients the development of targeted microbiome-based therapeutics and personalised antimicrobial regimens to mitigate infectious complications to improve their clinical outcomes.

A contribute on the fosfomycin mechanism of resistance in MDR organisms

A contribute on the fosfomycin mechanism of resistance in MDR organisms