High Antimicrobial Resistance Research Articles

Prevalence, regional distribution, and trends of antimicrobial resistance among female outpatients with urine Klebsiella spp. isolates: a multicenter evaluation in the United States between 2011 and 2019

BackgroundAntimicrobial resistance research in uncomplicated urinary tract infection typically focuses on the main causative pathogen, Escherichia coli; however, little is known about the antimicrobial resistance burden of Klebsiella species, which can also cause uncomplicated urinary tract infections. This retrospective cohort study assessed the prevalence and geographic distribution of antimicrobial resistance among Klebsiella species and antimicrobial resistance trends for K. pneumoniae in the United States (2011–2019).MethodsK. pneumoniae and K. oxytoca urine isolates (30-day, non-duplicate) among female outpatients (aged ≥ 12 years) with presumed uUTI at 304 centers in the United States were classified by resistance phenotype(s): not susceptible to nitrofurantoin, trimethoprim/sulfamethoxazole, or fluoroquinolone, extended-spectrum β-lactamase-positive/not susceptible; and multidrug-resistant based on ≥ 2 and ≥ 3 resistance phenotypes. Antimicrobial resistance prevalence by census division and age, as well as antimicrobial resistance trends over time for Klebsiella species, were assessed using generalized estimating equations.Results270,552 Klebsiella species isolates were evaluated (250,719 K. pneumoniae; 19,833 K. oxytoca). The most frequent resistance phenotypes in 2019 were nitrofurantoin not susceptible (Klebsiella species: 54.0%; K. pneumoniae: 57.3%; K. oxytoca: 15.1%) and trimethoprim/sulfamethoxazole not susceptible (Klebsiella species: 10.4%; K. pneumoniae: 10.6%; K. oxytoca: 8.6%). Extended-spectrum β-lactamase-positive/not susceptible prevalence was 5.4%, 5.3%, and 6.8%, respectively. K. pneumoniae resistance phenotype prevalence varied (p < 0.0001) geographically and by age, and increased over time (except for the nitrofurantoin not susceptible phenotype, which was stable and > 50% throughout).ConclusionsThere is a high antimicrobial resistance prevalence and increasing antimicrobial resistance trends among K. pneumoniae isolates from female outpatients in the United States with presumed uncomplicated urinary tract infection. Awareness of K. pneumoniae antimicrobial resistance helps to optimize empiric uncomplicated urinary tract infection treatment.

Antimicrobial resistance profile of Enterococcus species and molecular characterization of Vancomycin resistant Enterococcus faecium from the fecal samples of newly diagnosed adult HIV patients in Dar es Salaam, Tanzania

BackgroundEnterococci are becoming clinically more important especially among immunocompromised patients. Of concern are vancomycin resistant enterococci (VRE) which have both intrinsic and acquired forms of resistance. This work aimed to determine the antimicrobial resistance patterns of Enterococcus spp. and characterize VRE isolate obtained from HIV-infected patient using whole genome sequencing (WGS).Methods:Antimicrobial susceptibility testing was done on 57 enterococci isolates by both the disk diffusion method and Epsilometer test (E-Test). WGS was performed on VRE isolate determined by E-test.ResultsOut of the 57 enterococci isolates; 58% (33/57) were E. faecalis, 39% (22/57) E. faecium and 4% (2/57) were E. gallinarum. The highest antimicrobial resistance was observed in E. faecalis isolates. The most prevalent antimicrobial resistance was observed towards quinupristin-dalfopristin (56%, 32/57), followed by ciprofloxacin (28%), tigecycline (18%), daptomycin (16%), chloramphenicol (14%), ampicillin and teicoplanin (2%). Multidrug resistance (MDR) was detected in 11% (6/57) of the isolates. Vancomycin resistance and high-level gentamycin resistance (HLGR) were observed in one E. faecium and one E. faecalis isolates respectively. The VRE was typed as ST80, carried vanA and other resistance genes for aminoglycosides, tetracyclines, quinolones and ampicillin. Furthermore, the isolate had chromosomal mutations responsible for quinolone (gyrA (p.S83I) and parC (p.S80I) and ampicillin (pbp5) resistance.ConclusionsThe detection of VRE, HLGR and MDR in the study settings underscores the sustained surveillance of VRE in high-risk groups and institution of infection control measures for prompt identification and isolation of carriers to prevent the spread of VRE in the community and hospital settings.

Rhodococcus infection: a 10-year retrospective analysis of clinical experience and antimicrobial susceptibility profile.

Rhodococcus equi is an opportunistic pathogen known to cause pulmonary and extrapulmonary disease among immunocompromised patients. Treatment is frequently challenging due to intrinsic resistance to multiple antibiotic classes. While non-equi Rhodococcus spp. are prevalent, their clinical significance is poorly defined. There is also limited data on antibiotic susceptibility testing (AST) of Rhodococcus infection in humans. We conducted a single-center, retrospective cohort study evaluating clinical characteristics, microbiologic profile, and AST of Rhodococcus infections between June 2012 and 2022 at our tertiary academic medical center. Identification of Rhodococcus spp. was performed by Sanger 16S rRNA gene sequencing and/or matrix-assisted laser desorption ionization-time of flight mass spectrometry, and AST was performed by agar dilution. Three hundred twenty-two isolates of Rhodococcus spp. were identified from blood (50%), pulmonary (26%), and bone/joint (12%) sources. R. equi/hoagii, R. corynebacterioides, and R. erythropolis were the most frequently isolated species, with 19% of isolates identified only to genus level. One hundred ninety-nine isolates evaluated for AST demonstrated high-level resistance to amoxicillin/clavulanate, cephalosporins, and aminoglycosides. More than 95% susceptibility to imipenem, vancomycin, linezolid, rifampin, and clarithromycin was observed. Non-equi species showed a significantly more favorable AST profile relative to R. equi. Clinically significant Rhodococcus infection was rare with 10 cases diagnosed (majority due to R. equi) and managed. The majority of patients received 2- or 3-drug combination therapy for 2-6 months, with favorable clinical response. Significant differences in AST were observed between R. equi and non-equi species. Despite high antimicrobial resistance to several antibiotic classes, imipenem and vancomycin remain appropriate empiric treatment options for R. equi. Future research evaluating mechanisms underlying antimicrobial resistance is warranted.

Emergence of carbapenem resistant gram-negative pathogens with high rate of colistin resistance in Egypt: A cross sectional study to assess resistance trends during the COVID-19 pandemic

The current study investigated the temporal phenotypic and genotypic antimicrobial resistance (AMR) trends among multi-drug resistant and carbapenem-resistant Klebsiella pneumoniae, Acinetobacter baumannii, and Pseudomonas aeruginosa recovered from Egyptian clinical settings between 2020 and 2021. Bacterial identification and antimicrobial sensitivity of 111 clinical isolates against a panel of antibiotics were performed. Molecular screening for antibiotic resistance determinants along with integrons and associated gene cassettes was implemented. An alarming rate (98.2%) of these isolates were found to be phenotypically resistant to carbapenem. Although 23.9 % K. pneumoniae isolates were phenotypically resistant to colistin, no mobile colistin resistance (mcr) genes were detected. Among carbapenem-resistant isolates, blaNDM and blaOXA-48-like were the most prevalent genetic determinants and were significantly overrepresented among K. pneumoniae. Furthermore, 84.78% of K. pneumoniae isolates co-produced these two carbapenemase genes. The plasmid-mediated quinolone resistance genes (qnrS and qnrB) were detected among the bacterial species and were significantly more prevalent among K. pneumoniae. Moreover, Class 1 integron was detected in 82% of the bacterial isolates. This study alarmingly reveals elevated resistance to last-resort antibiotics such as carbapenems as well as colistin which impose a considerable burden in the health care settings in Egypt. Our future work will implement high throughput sequencing-based antimicrobial resistance surveillance analysis for characterization of novel AMR determinants. This information could be applied as a step forward to establish a robust antibiotic stewardship program in Egyptian clinical settings, thereby addressing the rising challenges of AMR.

Genomic insights into ESBL-producing Escherichia coli isolated from non-human primates in the Peruvian Amazon.

Extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae are on the WHO priority pathogens list because they are associated with high mortality, health-care burden, and antimicrobial resistance (AMR), a serious problem that threatens global public health and should be addressed through the One Health approach. Non-human primates (NHP) have a high risk of acquiring these antibiotic-resistant bacteria due to their close phylogenetic relationship with humans and increased anthropogenic activities in their natural environments. This study aimed to detect and analyze the genomes of ESBL-producing Escherichia coli (ESBL-producing E. coli) in NHP from the Peruvian Amazon. We collected a total of 119 fecal samples from semi-captive Saguinus labiatus, Saguinus mystax, and Saimiri boliviensis, and captive Ateles chamek, Cebus unicolor, Lagothrix lagothricha, and Sapajus apella in the Loreto and Ucayali regions, respectively. Subsequently, we isolated and identified E. coli strains by microbiological methods, detected ESBL-producing E. coli through antimicrobial susceptibility tests following CLSI guidelines, and analyzed their genomes using previously described genomic methods. We detected that 7.07% (7/99) of E. coli strains: 5.45% (3/55) from Loreto and 9.09% (4/44) from Ucayali, expressed ESBL phenotype. Genomic analysis revealed the presence of high-risk pandemic clones, such as ST10 and ST117, carrying a broad resistome to relevant antibiotics, including three blaCTX-M variants: blaCTX-M-15, blaCTX-M-55, and blaCTX-M-65. Phylogenomic analysis confirmed the clonal relatedness of high-risk lineages circulating at the human-NHP interface. Additionally, two ESBL-producing E. coli strains were identified as EPEC (eae) and ExPEC according to their virulence profiles, and one more presented a hypermucoviscous phenotype. We report the detection and genomic analysis of seven ESBL-producing E. coli strains carrying broad resistome and virulence factors in NHP from two regions of the Peruvian Amazon. Some of these strains are closely related to high-risk pandemic lineages previously reported in humans and domestic animals, highlighting the negative impact of anthropogenic activities on Amazonian wildlife. To our knowledge, this is the first documentation of ESBL-producing E. coli in NHP from the Amazon, underscoring the importance of adopting the One Health approach to AMR surveillance and minimizing the potential transmission risk of antibiotic-resistant bacteria at the human-NHP interface.

PREVALENCE AND ANTIBIOGRAM OF KLEBSIELLA SPECIES DETECTED IN CLINICAL

Objectives: We evaluated the prevalence rate and antibiogram of Klebsiella species isolated in various clinical samples, for effective management. Methods: The prospective study was undertaken to evaluate various clinical samples received in the microbiology laboratory for culture and sensitivity testing. Culture showing Klebsiella species were further processed for antibiotic susceptibility testing by the Kirby−Bauer disk diffusion test. Results: During the study period, 332 Klebsiella species were isolated in various samples and out of which 98.7% were Klebsiella pneumoniae and were predominately from urine samples (37%). All isolates were processed to determine their antibiogram. The highest antimicrobial resistance was observed for third and fourth-generation cephalosporines (more than 85%). Conclusion: It is concluded from our study that multidrug resistance K. pneumoniae are the emerging superbugs which require close monitoring and should be reported regularly which will guide clinicians in effectful management and thus help in preventing the spread of multidrug resistance Klebsiella and future threat.

Prevalence of secondary infections, antimicrobial susceptibility and predictors for mortality among critically ill COVID 19 patients admitted to an Intensive Care Unit in India

Background: Critically ill COVID 19 patients requiring intensive care unit admission are at an increased risk of secondary infections owing to the need for invasive or non invasive oxygen therapy, prolonged indwelling catheters and long stay in intensive care unit. Secondary infections can further alter the clinical course and outcomes of these patients Aims: In this study we aimed to investigate the prevalence, characteristics and factors associated with mortality in critically ill COVID 19 patients with secondary infections. Methods: This was a single centre retrospective cohort study of adult critically ill COVID 19 patients admitted to the intensive care unit of a tertiary care hospital in India during one year period from May 2020 to April 2021. Results: Among the 285 patients admitted to the intensive care unit 124 patients were identified with secondary infection. Out of the 250 isolates, 72.3% were gram negative bacilli with highest number of isolates recognised from blood (n=112, 44.8%). The most common organisms identified in our cohort were Klebsiella pneumoniae, Acinetobacter baumannii, Escherichia coli, Candida species and Enterococcus faecalis. Anti-microbial resistance was detected in 58.8% (n=147) of the isolates and majority of the patients received Carbapenem and Polymyxin. Patients with secondary infections were at increased risk of developing septic shock, acute kidney injury and also experienced higher mortality (50%, P-value &lt;0.001). In our study cohort, increasing cumulative dose of steroids [OR 1.002, 95% CI: 1.001-1.004)] and increasing length of intensive care unit stay [OR 1.071, (95% CI: 1.030-1.113)] were found to be predictive of mortality among patients with secondary infection. Conclusion: Secondary infections were high among the critically ill COVID 19 patients with high antimicrobial resistance and lead to high mortality. This being a single centre retrospective study, prospective evaluation with proper anti-microbial stewardship is needed for more precise results.

Bir mezbahada hindilerden izole edilen Campylobacter jejuni ve Campylobacter coli'nin antimikrobiyallere direnci

This study measured the percentage of thermotolerant Campylobacters (C. jejuni and C. coli) from samples obtained from a turkey slaughterhouse in Turkey and investigated their antimicrobial resistance to selected antimicrobials by disc diffusion method. Of 28 samples analyzed, 75% were positive for Campylobacter. Positivity in turkey cecum samples was 28.5% for C. coli and 71.4% for C. jejuni. Very high antimicrobial resistance rates were detected for ciprofloxacin and nalidixic acid while resistance to tetracycline was 100% for C. jejuni strains. No isolates showed multidrug resistance, or resistance to gentamicin or erythromycin. These results can provide information about the status of C. coli and C. jejuni resistant to fluoroquinolones, macrolides, aminoglycosides and tetracycline isolated from food animals in Turkey.

Resistome Diversity in Escherichia coli Isolates of Global Wastewaters.

Antimicrobial resistance (AMR) is a global health threat requiring urgent attention and effective strategies for containment. AMR is fueled by wastewater mismanagement and global mobility, disseminating multidrug-resistant (MDR) strains worldwide. While global estimates of AMR burden have been informative, community-level understanding has received little attention despite reports of high AMR prevalence in healthy communities. We assessed the "invasion" of antibiotic resistance genes (ARGs) into the normal human flora by characterizing AMR Escherichia coli in local wastewaters contributed by a healthy youth population. This study estimated 26% (out of 300 isolates) resistant and 59% plasmid-bearing E. coli in local wastewater. Of the 78 AMR isolates, the frequency of mono-resistance was higher against tetracycline (32%), followed by kanamycin (17%) and chloramphenicol (9%). Five isolates were potentially MDR. We further sequenced four MDRs and four sensitive strains to comprehend the genome and resistome diversity in comparison to the global wastewater E. coli (genomes from the PATRIC database). The whole-genome analysis revealed extensive genome similarity among global isolates, suggesting global dissemination and colonization of E. coli. Global wastewater resistome majorly comprised ARGs against aminoglycosides (26%), beta-lactam (17%), sulfonamide (11%), and trimethoprim (8%). Resistance to colistin, a last-resort antibiotic, was prevalent in MDRs of European and South Asian isolates. A systems approach is required to address the AMR crisis on a global scale, reduce antibiotic usage, and increase the efficiency of wastewater management and disinfection.

Antimicrobial resistance level and conjugation permissiveness shape plasmid distribution in clinical enterobacteria.

Conjugative plasmids play a key role in the dissemination of antimicrobial resistance (AMR) genes across bacterial pathogens. AMR plasmids are widespread in clinical settings, but their distribution is not random, and certain associations between plasmids and bacterial clones are particularly successful. For example, the globally spread carbapenem resistance plasmid pOXA-48 can use a wide range of enterobacterial species as hosts, but it is usually associated with a small number of specific Klebsiella pneumoniae clones. These successful associations represent an important threat for hospitalized patients. However, knowledge remains limited about the factors determining AMR plasmid distribution in clinically relevant bacteria. Here, we combined in vitro and in vivo experimental approaches to analyze pOXA-48-associated AMR levels and conjugation dynamics in a collection of wild-type enterobacterial strains isolated from hospitalized patients. Our results revealed significant variability in these traits across different bacterial hosts, with Klebsiella spp. strains showing higher pOXA-48-mediated AMR and conjugation frequencies than Escherichia coli strains. Using experimentally determined parameters, we developed a simple mathematical model to interrogate the contribution of AMR levels and conjugation permissiveness to plasmid distribution in bacterial communities. The simulations revealed that a small subset of clones, combining high AMR levels and conjugation permissiveness, play a critical role in stabilizing the plasmid in different polyclonal microbial communities. These results help to explain the preferential association of plasmid pOXA-48 with K. pneumoniae clones in clinical settings. More generally, our study reveals that species- and strain-specific variability in plasmid-associated phenotypes shape AMR evolution in clinically relevant bacterial communities.

Epidemiology, Clinical Conditions, Pathogenesis and Mechanism of Resistant of Acinetobacter baumannii: A Narrative Review

The world is facing a growing threat from multidrug-resistant (MDR) gram negative “superbugs,” such as Acinetobacter baumannii. This morbidity and mortality loss caused there of indirectly hampers the economic developments in countries. These multidrug-resistant A. baumannii worldwide represents a major public health problem. The development of antibiotics decreased the mortality among the human and animals leading to a better life expectancy. But the injudicious use of antimicrobials and selection pressure the microbes have developed resistance which became more prominent during last few decades. High antimicrobial resistance was observed against all β-lactam and non- β-lactam antibiotics by the MBL producers. In developing countries also, the misuse and underuse of antimicrobials due to lack of awareness of patients, medical workers and financial problems emerged the antimicrobial resistant strains. Due to rapid globalization of human population by travel and other factor these resistant strains spread easily between developed and developing countries making it a global problem. Bangladesh Journal of Medical Microbiology, July 2023;17 (2):88-92

In vitro evaluation of biofilm phenotypic and genotypic characteristics among clinical isolates of Pseudomonas aeruginosa in Hamadan, West of Iran.

Due to high antimicrobial resistance and biofilm-forming ability, Pseudomonas aeruginosa is one of the seriously life-threatening agents causing chronic and nosocomial infections. This study was performed to determine the antibiotic resistance pattern, biofilm formation, and frequency of biofilm-related genes in P. aeruginosa strains. In total, 123 P. aeruginosa isolates were collected from different clinical sources. Antimicrobial susceptibility testing (AST) was performed to detect multidrug-resistant P. aeruginosa (MDRPA) isolates. To evaluate the biofilm-forming isolates, the microtiter plate (MTP) method was carried out. Also, the prevalence of biofilm genotype patterns, including pslA, pslD, pelA, pelF, and algD genes, was detected by polymerases chain reaction (PCR). According to our findings, the highest resistance and susceptibility rates were found in ceftazidime with 74.7% (n = 92) and ciprofloxacin with 42.2% (n = 52), respectively. In our study, the highest level of antibiotic resistance belonged to wound isolates which meropenem had the most antibacterial activity against them. In total, 86.1% (n = 106) P. aeruginosa isolates were determined as MDRPA, of which 61.3% (n = 65) were able to form strong biofilm. The highest and lowest frequency of biofilm-related genes among biofilm producer isolates belonged to pelF with 82.1% (n = 101) and algD with 55.2% (n = 68), respectively. The findings of the conducted study indicate a significant relationship between MDRPA and biofilm genotypic/phenotypic patterns, suggesting the necessity of a careful surveillance program in hospital settings.

Bacterial abundance and antimicrobial resistance patterns of uropathogens among pregnant women with asymptomatic bacteriuria: Association with glycemic status

ObjectivesAntimicrobial resistance (AMR), a growing global menace, poses a significant threat to maternal and fetal health. Gestational diabetes mellitus (GDM) causes double trouble in pregnancy, increasing the risk of a variety of infectious morbidities while also raising the possible association with AMR. Asymptomatic bacteriuria (ASB) is a common problem in pregnancy, but little research has been done to date explicitly examining the relationship between GDM and ASB and yielded conflicting results. Even fewer studies have specifically examined the relationship between GDM and AMR in women with ASB. Retrieving the most recent information on the disease burden, the range of causative pathogens, their patterns of AMR, and associated risk factors in pregnant women is crucial to stop the exponential rise in AMR in pregnancy and improve maternal and neonatal outcomes of infectious morbidities. Hence, this study was planned to investigate the association between glycemic status and the contemporary bacterial profile, antimicrobial resistance(AMR), and associated variables among pregnant women with ASB Study designThis prospective, hospital-based, cross-sectional study was conducted among 320 pregnant women; divided into two groups, GDM and non-GDM. Data regarding sociodemographic and clinical characteristics were collected using a structured questionnaire. Clean-catch midstream urine samples were investigated for the presence of significant bacterial uropathogens and their AMR pattern was determined using recommended culture methods. ResultsWe found ASB in 46.25% of study participants with significantly higher occurrence in the GDM group. Dominant isolates were Escherichia coli followed by Klebsiella pneumoniae. AMR was noted in 51.35% and multidrug resistance(MDR) in 23.65% of isolates. Overall AMR, MDR and higher degrees of AMR were higher among uropathogens isolated from the GDM group as compared to the non GDM group, although the difference was not statistically significant. ConclusionThe high occurrence of ASB in pregnancy along with substantially high AMR in this study suggests the need for effective infection control and stewardship programmes. By defining the association of ASB and AMR with hyperglycemia, our study calls for the exploitation of this potential association in halting the pandemic of AMR and in improving the management of infectious morbidities, thus in-turn alleviating their undesired maternal and infant outcomes.

Antibacterial Activity of River Water Bacteriophage against Multidrug-resistant Gram-negative Bacteria, An In vitro Study

Microbes show a high antimicrobial resistance due to a high rate of mutations predisposed by many factors, especially the abuse of antibiotics. Therefore, there is a great need for an alternative therapeutic agent for infectious diseases caused by microbes resistant to antibiotics. Bacteriophages are viruses parasitizing microbes, that got a big scientist’s attention due to their ability as an alternative therapy for severe bacterial infections. This study is devoted to identifying bacteriophage from river water on tested pathogenic isolates isolated from clinical cases of UTI in vitro and finding out the effect of phage on these bacterial isolates as an initial step of further in vivo phage therapeutic study on the same tested isolates. The results showed a significant bactericidal effect of the isolated bacteriophages against the pathogenic bacterial isolates.

Antimicrobial resistance as a super wicked problem: how do we engage the public to be part of the solution

Antimicrobial resistance (AMR) is now regarded as one of the greatest global challenges of the 21st century. The complexity, urgent timeframe, and lack of clear solution to AMR have contributed to its classification as a 'super wicked problem'. Yet knowledge surveys of the general public have found that they still harbour numerous misconceptions linked to both the sources and impact of AMR. This confusion is compounded by AMR being a One Health issue, and therefore a factor in not just human health but in other industries, such as farming. This can further inhibit understanding and knowledge transfer around AMR for those without a prior knowledge base. In order to address the escalating risk that AMR presents, however, it is essential to address this knowledge gap and engage with the public to support wide scale changes in behaviour and consumer choice. The WHO now requires national action plans tackling AMR to include patient and public involvement/engagement (PPI/E) to support changing the trajectory of AMR. Despite this, little detail is available as part of strategic plans on how PPI/E should be undertaken in order to aid implementation. This paper discusses a number of approaches to support the design and delivery of PPI/E in relation to AMR, including the different social behaviour models underlying successful PPI/E strategies, and key considerations linked to specific activity types. The framework produced includes features for steps from initial planning and design through to evaluation. The aim is to help improve the ability of scientists and healthcare professionals to produce high quality AMR PPI/E.

MICROBIOTA&lt;b&gt; &lt;/b&gt;AMBIENTAL DEL DEPARTAMENTO DE NEONATOLOGIA EN EL INSTITUTO NACIONAL MATERNO PERINATAL, LIMA&lt;b&gt;, PERÚ&lt;/b&gt;

Introduction. Healthcare-associated infections (IAAS) increase neonatal morbidity and mortality. Identifying the microbiological profile and sensitivity of the microbiota allows us to reduce infection rates, rationalize the use of antibiotics and improve neonatal survival. Objectives. To know the environmental microbiota and antimicrobial sensitivity in the Department of Neonatology (DN). Methods. Observational, descriptive, cross-sectional study, carried out between April and May 2021, in the Intensive Care, Intermediate and Immediate Care services of the DN of the Instituto Nacional Materno Perinatal, a reference center for maternal and neonatal care. 144 surfaces were selected from the hospitalized patient environment. Using swabbing technique, samples were obtained and then seeded in common and selective culture media. Sensitivity was determined using Kirby-Bauer diffusion disks, the analysis of variables was performed with SPSS version 22.0 Results. Of 147 samples, 67% gave positive cultures with pathogenic bacteria. In immediate care 50% tested positive, in intermediate care 46.5% and in NICU 39.7%. The 100% contaminated surfaces were fan screens, electroencephalogram monitor, chart holders and scales. Of 41 hands of health personnel, 29.3% were contaminated: 54.5% nursing technicians, 30% doctors and 23% nursing graduates. The isolated germs were SCN (67%) sensitive to vancomycin, Enterococcus (16.5%) sensitive to ampicillin and vancomycin, Pseudomonas (8.2%) to meropenem, Escherichia coli (2.4%) to gentamicin and amikacin, Klebsiella (1.2%). Conclusion. Pathogens causing IAAS were isolated on surfaces in the environment of our patients. The bacterial agents found have high antimicrobial resistance and virulence.

Investigation of Virulence Factors, Phylogenetic Group Features, and the Presence of ST131 Clone in Escherichia coli Isolates, a Urinary Tract Infection Agent in Children

Urinary tract infection (UTI) caused by Escherichia coli is a significant health issue in children. Today especially E.coli O25b/ST131, defined as a pandemic clone, is a serious public health problem due to its high virulence and antimicrobial resistance rates. In this study, a total of 200 (100 first and 100 recurrent UTI-causing) E.coli isolates from urine samples sent to the Ankara University School of Medicine Cebeci Training and Research Hospital Central Laboratory between January and September 2021 with the preliminary diagnosis of UTI in pediatric patients aged three to 18 years were analyzed for antimicrobial resistance rates, phylogenetic group distributions, virulence factor frequencies and whether they belong to the O25b/ST131 clone. It is aimed in this study that, the obtained data will shed light on new studies for diagnosis, treatment and prophylaxis options that can be developed for more effective UTI management by contributing to the surveillance studies in our country. Antimicrobial susceptibility of E.coli isolates identified by conventional methods was evaluated by Kirby-Bauer disc diffusion method and extended spectrum beta-lactamase (ESBL) production was evaluated by double disc synergy test. Polymerase chain reaction (PCR) was used for the investigation of phylogenetic grouping, the O25b/ST131 clone, virulence genes and the molecular level classification of the isolates detected as uropathogenic E.coli (UPEC). Pulsed-field gel electrophoresis (PFGE) was performed with the isolates collected at different times from the same patient. The highest antimicrobial resistance rates observed were against ampicillin (n= 100, 50%), cefazolin (n= 99, 49.5%), trimethoprim-sulfamethoxazole (n= 55, 27.5%), amoxicillin-clavulanic acid (n= 43, 21.5%) and cefotaxime (n= 43, 21.5%). In recurrent UTI agents, resistance rates were higher for cefotaxime (n= 29, 29%), trimethoprim-sulfamethoxazole (n= 35, 35%) and cefepime (n= 25, 25%) and in O25b/ST131 isolates (n= 67) the rates were higher for amikacin (n= 3, 4.5%), gentamicin (n= 10, 14.9%) and ciprofloxacin (n= 17, 25.4%) when compared to the first UTI agents and non-O25b/ ST131 isolates (p< 0.05). It was found that 29% (n = 58) of the isolates were multidrug resistant (MDR) and 19% (n = 38) produced ESBL.The rate of recurrent UTI agents was found to be higher among ESBL producing isolates and/or MDR isolates (n= 36, 62% and n= 27, 71%, respectively, p< 0.05). It was found that 45.5% (n= 91) of the isolates were in D, 37.5% (n= 75) in B2, 12.5% (n= 25) in A, and 4.5% (n= 9) in B1 phylogenetic groups and isolates belonging to B2 and D phylogenetic groups had higher antibiotic resistance rates and carried more virulence genes (p< 0.05). Of the isolates, 33.5% (n= 67) were found to belong to the O25b/ST131 clone, no significant difference was found between the O25b/ST131 rates among the first and recurrent UTI agents (p> 0.05). It was determined that the isolates most frequently carry virulence genes for adhesion [fimH 97% (n= 194), papA 57% (n= 114), yfcV 49.5% (n= 99)] and iron uptake systems [fyuA 85.5% (n= 171), chuA 78% (n= 156), iutA 73% (n= 146)]. All virulence factors were detected more frequently in isolates belonging to the O25b/ST131 clone (p< 0.05). Of the isolates, 97% (n= 65) belonging to the O25b/ST131 clone and 27.1% (n= 36) not belonging to this clone were defined as UPEC with molecular analysis (p< 0.0001). Thirty-three isolates belonging to 15 patients were evaluated with PFGE, and it was observed that the latter isolate and the first isolate of eight patients (53%) had the same band profile. Focusing on surveillance, diagnostic testing, treatment algorithms, and preventive measures for E.coli and especially for ST131 clone, which is frequently observed as causative agent in childhood UTIs, will help to manage challenging E.coli infections.

Aptitude of Uropathogenic Escherichia coli in Renal Transplant Recipients: A Comprehensive Review on Characteristic Features, and Production of Extended Spectrum β-Lactamase.

Urinary tract infection is the most common infection in almost half of the renal transplant patients. The development of UTI in these patients may progress to bacteremia, acute T cell-mediated rejection, impaired allograft function, or allograft loss, along with the increased risk of hospitalization and death. Among various pathogens implicated, Uropathogenic E. coli (UPEC), especially sequence type 131 (ST131), is the most virulent and multidrug-resistant pathogen. High antimicrobial resistance to most β-lactam antibiotics, mediated by extended spectrum β-lactamases (ESBLs) produced by UPEC, is a challenge in the clinical management of UTIs in kidney transplant recipients. Indeed, multidrug resistance to β-lactam antibiotics is a direct consequence of ESBL production. Resistance to other antibiotics such as aminoglycosides, fluoroquinolones, and trimethoprim-sulphamethoxazole has also been reported in ESBLs-producing UPEC, which reduces the therapeutic options, rising healthcare-associated costs and subsequently leads to renal failure or even graft loss. In this review, we aimed to discuss the post-transplant risk factors of UTI, UPEC virulence factors (VF), and the related factors including quorum sensing, and stress resistance genes. Furthermore, we searched for the current treatment strategies and some of the alternate approaches proposed as therapeutic options that may affirm the treatment of ESBL-producing UPEC.

Antimicrobial resistance and antagonistic features of bivalve-associated Vibrio parahaemolyticus from the south-west coast of India.

Vibrio parahaemolyticus, a potent human and aquatic pathogen, is usually found in estuaries and oceans. Human illness is associated with consuming uncooked/partially cooked contaminated seafood. The study on bivalve-associated V. parahaemolyticus revealed that the post-monsoon season had the highest bacterial abundance (9 ± 1.5 log cfu) compared to the monsoon season (8.03 ± 0.56 log cfu). Antimicrobial resistance (AMR) profiling was performed on 114 V. parahaemolyticus isolates obtained from bivalves. The highest AMR was observed against ampicillin (78%). Chloramphenicol was found to be effective against all the isolates. Multiple antibiotic resistance index values of 0.2 or higher were detected in 18% of the isolates. Molecular analysis of antimicrobial resistant genes (ARGs) revealed the high prevalence (100%) of the TEM-1 gene in the aquatic environment. After plasmid profiling and curing, 41.6% and 100% of the resistant isolates were found to be sensitive to ampicillin and cephalosporins, respectively, indicating the prevalence of plasmid-associated ARGs in the aquatic environment. A study to evaluate the antagonistic properties of Bacillus subtilis, Pseudomonas aeruginosa, and Bacillus amyloliquefaciens against V. parahaemolyticus isolates identified the potential of these bacteria to resist the growth of V. parahaemolyticus.

Microorganisms isolated in patients with post-cardiac surgery mediastinitis at a cardiology hospital of Mexico City.

Mediastinitis after cardiovascular surgery gives rise to prolonged hospital stay and increased medical care costs, and is associated with high in-hospital mortality. To describe the clinical characteristics of patients with post-surgical mediastinitis, including the isolated microorganisms, resistance profile, and in-hospital survival. Cross-sectional study of patients with bacteriologically-confirmed post-surgical mediastinitis cared for at a cardiology hospital in Mexico City between January 2017 and March 2019. Fifty-eight cases of mediastinitis were included. Median age was 67 years. Most subjects were males who underwent myocardial revascularization. During in-hospital follow-up, all-cause and mediastinitis-related mortality were 27.6% and 20.7%, respectively. Staphylococcus aureus, Staphylococcus epidermidis and Escherichia coli were the most commonly isolated microorganisms. High resistance to methicillin was found in coagulase-negative staphylococci, as well as high expression of extended-spectrum beta-lactamases in Escherichia coli and Klebsiella pneumoniae strains. High mortality and significant antimicrobial resistance were found in patients with post-cardiac surgery mediastinitis.