Extended-spectrum Beta-lactamase Positivity Research Articles

Molecular Characteristics of Cephalosporin Resistant Escherichia coli and Klebsiella pneumoniae Isolated from Children in a Tertiary Care Centre of Central Kerala, India

Aims: The study was aimed to determine the molecular characteristics of extended-spectrum beta-lactamases (ESBL) producing cephalosporin-resistant Escherichia coli and Klebsiella pneumoniae isolated from children below ten years of age. Background: Geographically diverse variations in the prevalence of ESBL genes were reported. No data were available on the prevalence of ESBL genes in central Kerala, India, among children below 10 years of age. Methods: A cross-sectional study was performed to analyze ESBL genes in cephalosporin-re-sistant E. coli and K. pneumoniae strains isolated from samples received in the Microbiology la-boratory of a tertiary care centre during the period between May 2021 and July 2022. The strains showed that ESBL + cephalosporin resistance was subjected to PCR-based genotyping for the genes such as bla (beta-lactamase) CTX-M-1, blaCTX-M-15, blaCTX-M-U, blaTEM, blaPER and SHV. Results: Among the total 228 samples analyzed, 136 (60%) had no growth. Ninety-two (40 %) samples showed growth of E. coli and K. pneumoniae. Among the isolates that showed growth, 39 (42%) were sensitive, and the remaining 53 (57%) were resistant to third-generation cephalospor-ins. Among the isolates showed resistance, 22 (42%) were ESBL positive and 31 (58%) were ESBL negative. Among the positive ESBL, nine E. coli strains (60%) were positive for CTX-M-15 and CTX-M-1. CTX-M-15 and CTX-M-U were present in six (85%) K. pneumoniae with ESBL +. Conclusion: E. coli and K. pneumoniae isolated from specimens of children below ten years of age showed 41-42% ESBL producers. Prevalent ESBL-producing genes in E. coli were CTX-M-15 and CTX-M-1. CTX-M-15 and CTX-M-U were prevalent in ESBL-producing K. pneumoniae.

Transition mutation bias is crucial to adaptive extended spectrum beta lactamase (ESBL) resistance evolution

The importance of slow accumulation of mutation in the nucleic acids of bacteria and the possibility of organismal transcriptional modification to suit their adaptation are key drivers favouring natural selection and subsequently adaptive evolution. This study was aimed at providing insight into factors influencing adaptive extended spectrum beta lactamase (ESBL) resistance evolution. A total of twenty-six (26) extended spectrum beta lactamase-producing Gram-negative bacteria isolated in our previous study were subjected to uniplex and multiplex polymerase chain reaction (PCR) and sequencing prior to mutation discovery analyses, while the maximum likelihood value, transition-transversion ratio, tajimas neutrality test, nucleotide diversity and selection analyses were estimated following standard recommended protocols. Results obtained depict the PCR discriminated ESBL alleles as; TEM (n = 11.5 %), CTX-M (n = 15.4 %), SHV (n = 19.2 %) while the co-occurred ESBL alleles were estimated as CTX-M and TEM (n = 3.85 %), CTX-M and SHV (n = 15.4 %), TEM and SHV (n = 23.1 %), CTX-M, TEM and SHV (n = 11.5 %). The transition, transversion, deletion and insertion distribution pattern were evaluated as; TEM (46, 39,11 and 4 %), SHV (50, 31, 8 and 11 %) and CTX-M (60, 21,12 and 7 %) (p < 0.05) respectively. The maximum likelihood value, transition-transversion ratio, tajimas neutrality test, nucleotide diversity and selection analyses for TEM, SHV and CTX-M were (−8436, 1.18, 5.2, 62 % and 84.9 %,), (−8321, 1.60, 5.4, 68.9 % and 97.8 %) and (−7284, 2.86, 6.0, 55.2 % and 77.2 %) sequentially. Our findings therefore have shown that adaptive ESBL resistance evolution is driven by transition mutation, positive natural selection and ESBL gene flow. It is thus imperative to state that understanding these adaptive resistance driven factors and how they operate is crucial to deciphering the fundamental principles of adaptive evolution that might help circumvent the global challenges of antibiotic resistance.

Prevalence of extended-spectrum beta-lactamases producing isolates obtained from patients of pediatric critical care unit in a tertiary care hospital

Background: Over the past decades, antibiotic-resistant Gram-negative bacteria commonly Enterobacteriaceae such as Escherichia coli and Klebsiella pneumoniae have increased significantly. These microorganisms have great clinical importance because they increase hospital stay of the patients in the intensive care unit (ICU) leading to high morbidity and mortality. Because of their role in increasing morbidity and mortality, this study was performed to isolate extended-spectrum beta-lactamase (ESBL) producing Gram-negative bacilli screened by phenotypical method and further projected into molecular characterization by polymerase chain reaction. Aims and Objectives: The aims and objectives are to isolate the Gram-negative multidrug-resistant strains from clinically suspected bacterial infections in patients of neonatal, sick newborn, and pediatric ICU and to study antibiotic sensitivity pattern of isolated Gram-negative multidrug-resistant strains with special reference to molecular characterization. Materials and Methods: A total of 100 Gram-negative bacilli were isolated. Screening of ESBL positivity was done by double-disk synergy test (combined disc test method). Their antibiogram profile was interpreted. With the use of designed primers, 26 ESBL isolates each of E. coli and Klebsiella spp. were processed for molecular analysis of beta-lactamase family genes TEM and CTX-M. Results: Within the 100 samples, majority of the isolates (45%) were Klebsiella spp. and 40% was E. coli isolates. Highest ESBL-producing organisms were observed within E. coli (65%). Prevalence bla-TEM gene was highest followed by bla-CTX-M. These ESBL-producing organisms were found to be resistant to multiple classes of antibiotics. With extensive ESBL surveillance and proper usage of antibiotics, this threatening rise of antibiotic resistance can be mitigated. Conclusion: Gram-negative isolates showed high resistance to commonly used antibiotics. Significant proportions of them were MDR strains. Such high antibiotic resistance is associated with significant morbidity and mortality among pediatric population. MDR along with possession of ESBL associated resistance genes among Gram-negative bacilli pose a serious problem in therapeutic management of patients. Our study signifies that there is a high probability of Gram- negative bacilli to be multi-drug resistant and ESBL positive and earliest detection of such cases should be made.

Study of Plasmid-Mediated Extended-Spectrum Beta-Lactamase-Producing Clinical Strains of Enterobacteriaceae From Tabuk Region.

Extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae threaten infection treatment globally. This study aims to assess ESBLs-E prevalence and multidrug-resistant organisms (MDR) in clinical specimens from Tabuk, KSA. A cross-sectionalresearchwascarriedoutin March-May 2023.Acollectiveof 90 Enterobacteriaceae isolates were identified from clinicalspecimens.The specimen was identified by standard methods. The Enterobacteriaceae member was screed for ESBL production by screening and confirmatory as per the Clinical and Laboratory Standards Institute (CLSI). E. coli was the most common isolate, followed by Proteus mirabilis and Citrobacter sp, Klebsiella oxytoca, Klebsiella pneumonia, Proteus vulgaris and Morganella morganii. Among the sample, the majority of isolates were from urine (47.8%) followed by pus (25.6%) and the least from other body fluids (6.7%). The E. coli showed the highest average antibiotic resistance (73.7%) among all the antibiotics used followed by P. mirabilis (70.4%), K. pneumoniae (70%), P. vulgaris (69.8%), M. morganii and Citrobacter (69.4% both), and K. oxytoca (68.8%). There was a 41.2% average reduction in ESBL positivity from phenotypic to confirmatory test results. The highest reduction was observed among M. morganii (66.7%) and the least was observed in E. coli (17.1%). Most of the ESBL-producing isolates were found mainly in blood and urine samples. The most frequent ESBL-producing Enterobacteriaceae were K. pneumoniae and E. coli. The best options for treating Enterobacteriaceae that produce ESBL are Amoxicillin, Amikacin, and Cefoxitin. ESBL-producing isotopes showed a high resistance rate to cefepimeand cefotaxime compared to non-ESBL producers. It is of utmost importance to implement reliable infection control measures in healthcare institutions nationwide.

Effects of COVID-19 pandemic on healthcare-associated infections, antibiotic resistance and consumption rates in intensive care units.

This paper aimed to evaluate the effects of the COVID-19 pandemic on healthcare-associated infections (HAIs), antibiotic resistance and consumption rates in intensive care units (ICUs) of a tertiary care university hospital. Between 1 January 2018 and 31 December 2021, adult patients diagnosed with HAIs in ICUs were investigated retrospectively. Patients were divided into pre-pandemic (2018-2019) and pandemic periods (2020-2021). Antibiotic consumption index was calculated via using the formula of (total dose (grams)/defined daily dose (DDD) x total patient days) x1000. A p value below 0.05 was accepted as statistically significant. The incidence of HAIs (per 1000 patient days) in the ICU of COVID-19 patients was 16.59, while it was 13.42 in the other ICUs during the pandemic period (p=0.107). The bloodstream infection (BSI) incidence was 3.32 in the pre-pandemic period and 5.41 in the pandemic period in ICUs other than the ICU of COVID-19 patients (p<0.001). In the pandemic period, the BSI incidence rate was significantly higher in the ICU of COVID-19 patients than in the other ICUs (14.26 vs 5.41, p<0.001). Central venous catheter bloodstream infections incidence rate was 4.72 in the pre-pandemic and 7.52 in the pandemic period in ICUs other than the ICU of COVID-19 patients (p=0.0019). During the pandemic period, the bacteraemia episode rates of Acinetobacter baumannii (5.375 vs 0.984, p<0.001), Enterococcus spp. (1.635 vs 0.268, p<0.001) and Stenotrophomonas maltophilia (3.038 vs 1.297, p=0.0086) in the ICU of COVID-19 patients were significantly found higher than others. The extended-spectrum beta-lactamase (ESBL) positivity rates for Klebsiella pneumoniae and Escherichia coli were 61% and 42% in the pre-pandemic period; 73% and 69% in the pandemic period in ICUs other than the ICU of COVID-19 patients (p>0.05). In the pandemic period, the ESBL positivity rates for K. pneumoniae and E. coli were 83% and 100% in the ICU of COVID-19 patients, respectively. Meropenem (p<0.001), teicoplanin (p<0.001) and ceftriaxone (p<0.001) consumptions were increased while ciprofloxacin (p=0.003) consumption was decreased in all ICUs after the pre-pandemic period. BSI and CVCBSI incidence rates were significantly increased in all ICUs after the COVID-19 pandemic in our hospital. Bacteraemia episode rates of A. baumannii, Enterococcus spp. and S. maltophilia in ICU of COVID-19 patients were significantly found higher than others. In addition, meropenem, teicoplanin and ceftriaxone consumptions were increased in all ICUs after the COVID-19 pandemic.

Secondary Infections in Critical Patients with COVID-19 Associated ARDS in the ICU: Frequency, Microbiologic Characteristics and Risk Factors.

To determine frequency, microbiologic characteristics and risks of secondary infections in patients with Coronavirus disease 2019 (COVID-19) associated acute respiratory distress syndrome (ARDS). An Observational study. COVID-19 intensive care unit (ICU), University of Health Sciences, Diskapı Yildirim Beyazit Research and Training Hospital, Turkey, from July 2020 to January 2021. Demographic data of the COVID-19 patients with ARDS, was collected with reference to (age, gender), comorbidities, illness scores, ICU management modalities, hospital, and ICU stay durations and ICU outcomes. Secondary infections [bloodstream infection (BSI), possible lower respiratory tract infection (pLRTI) or urinary tract infections (UTI)], microbiologic pathogens, and resistant patterns were recorded. A total of 205 COVID-19-related ARDS patients were included in this study. Out of them, 61 (29.8%) were diagnosed with secondary infection, 27 (13.1%) had at least one BSI, 20 (9.8%) had at least one pLRTI, and 34 (16.6%) had at least one UTI. Gram-negative pathogens were the most common cause of secondary infections (66/91, 72.5%). Klebsiella spp for BSI (10/19, 52.6%), Acinetobacter baumannii for pLRTI (10/18, 55.6%), and Escherichia coli for UTI (29/40, 72.5%) were the main causative agents. Among all Gram-negative bacteria, Carbapenem resistant was 62.1% (41/66) and extended-spectrum beta-lactamases positivity was 22.7% (15/66). At multivariable analysis, application of mechanical ventilation (MV) longer than 48 h, central catheterisation longer than 72 h, ICU stay longer than 10 days, and the time from hospitalisation to admission to the ICU longer than 48 h were associated with secondary infections. Patients with COVID-19 associated ARDS had a high rate of secondary infections. In order to reduce secondary infection in these patients, MV duration and ICU stay should be shortened and invasive catheters should be removed as soon as possible. SARS-CoV-2, COVID-19, Acute respiratory distress syndrome,Secondary infections.

647. Cefepime Versus Carbapenems for the Treatment of ESBL-producing Enterobacterales among Non-blood Isolates

Abstract Background The incidence of organisms with extended-spectrum beta-lactamases (ESBLs) is increasing. The data for using cefepime in ESBL-producing Enterobacterales infections is conflicting. More favorable outcomes are likely if minimum inhibitory concentrations (MICs) &amp;lt; 2 mcg/mL. The aim of this study is to compare the efficacy of cefepime versus carbapenems for ESBL-producing, non-bloodstream Enterobacterales infections. Methods This study was a single-center retrospective cohort study of patients who received cefepime or a carbapenem for at least 72 hours for the definitive treatment of an ESBL-producing Enterobacterales non-bloodstream infection between Jan. 1, 2011 and Sept. 30, 2021. ESBL production was identified if the isolate either had a positive confirmatory ESBL test from VITEK 2 (bioMérieux) or phenotypic resistance to ceftriaxone. Isolates had to have a MIC &amp;lt; 2 mcg/mL to cefepime or be susceptible to carbapenems. Isolates with a cefepime MIC 4-8 mcg/mL were not included due to likely higher rates of treatment failure. The primary endpoint was clinical failure, defined as persistence of symptoms requiring escalation of therapy or death. Descriptive statistics were used to compare groups. A univariate analysis and odds ratio was calculated for clinical outcomes. Results One hundred patients were included. Twenty-two patients received cefepime and 78 received a carbapenem. Table 1 describes patient characteristics and clinical outcomes. Most patients had a urinary tract infection (UTI) (94%). More patients receiving cefepime were admitted to the intensive care unit (40.9% versus 15.4%). Treatment with cefepime displayed higher rates of clinical failure when compared to treatment with carbapenems (13.6% versus 6.4%). Cohen’s d-test for clinical failure was 0.46, indicating a medium effect. Conclusion Based on our analysis, cefepime may have higher rates of clinical failure when compared to carbapenem treatment for ESBL-producing Enterobacterales. Most of our patients were treated for UTIs and the sample size for both arms were limited, particularly for the cefepime arm. Further research is needed to confirm the role of cefepime as a carbapenem-sparing option in the treatment of these drug-resistant infections. Disclosures Madeline King, PharmD, Shionogi: Honoraria|Tetraphase: speakers' bureau.

Resistance of Escherichia coli and Klebsiella pneumoniae Isolates Grown from Blood Samples at a University Hospital: A Six-Year Evaluation Comparative to the COVID-19 Pandemic Period

Kan dolaşım enfeksiyonları (KDE) yüksek mortalite ve morbidite ile seyreden en önemli nozokomiyal enfeksiyonlardandır. Gram negatif bakteriler içerisinde en sık KDE etkeni olan bakterilerden ikisi Escherichia coli ve Klebsiella pneumoniae’dır. Antimikrobiyal direnç bu bakterilerin neden olduğu enfeksiyonların tedavisinin önündeki en büyük sorunlardan birisidir. Direnç sürecinin izlenmesi ve seyrinin belirlenmesi, ampirik tedaviye yön vermesi açısından önemlidir. Bu çalışmada kan dolaşımı örneklerinden izole edilen K. pneumoniae ve E. coli bakterilerinin direnç durumları değerlendirilerek, hastanemizdeki güncel verilerin ortaya konulması amaçlanmıştır. Çalışmada 2016-2021 yılları içerisinde kan örneklerinden izole edilen E. coli ve K. pneumoniae bakterilerinin antibiyotiklere karşı direnç durumları, laboratuvar bilgi sistemi verilerinden alınarak geriye dönük olarak incelenmiştir. Çalışmada 963 kan kültüründen 659 E. coli ve 304 K. pneumoniae izole edilmiştir. Bu bakterilerin %34’ü yoğun bakımlardan, %66’sı diğer kliniklerde yatan hastalardan izole edilmiştir. Tüm antibiyotikler değerlendirildiğinde, yoğun bakımlarda yatan hastalarda direnç oranlarının daha yüksek olduğu görülmüştür. En etkili antibiyotik amikasin olarak bulunmuştur. Yoğun bakım ünitesi izolatlarında Genişlemiş spektrumlu beta laktamaz (GSBL) pozitifliği %51 olarak bulunurken, diğer kliniklerde bu oran %36 olarak tespit edilmiştir. GSBL pozitif izolatlarda direnç oranlarının anlamlı oranda yüksek olduğu görülmüştür. K. pneumoniae izolatlarında amikasin ve meropenem sonuçlarında pandemi öncesi ve pandemi dönemi arasında anlamlı bir fark görülmüştür. Ülkemizdeki sağlık merkezlerinin kendi antibiyotik kullanım politikalarını bilimsel çalışma verilerini dikkate alarak belirlemeleri yararlı olacaktır. Bu nedenle bu çalışma sonuçlarının E. coli ve K. pneumoniae kaynaklı sepsiste uygulanacak olan ampirik tedavi modellerini belirlemede yol gösterici olabileceğini düşünüyoruz.

Prevalence of ESBL genes in Klebsiella pneumoniae from individuals with community-acquired urinary tract infection in rural communities of Enugu State, Nigeria

Background: The emergence and spread of extended-spectrum beta-lactamase (ESBL) producing Enterobacteriaceae is now a major challenge in treating urinary tract infections. This study was conducted to determine the Prevalence of ESBL genes in Klebsiella pneumoniae and the influence of these genes on the antimicrobial susceptibility patterns of the isolates, obtained from community acquired urinary tract infection in Enugu state rural communities. Method: A total of 735 clean catch mid-stream urine samples were collected from February, 2021 to June, 2021. The urine samples were cultured and Klebsiella pneumoniae were identified morphologically, biochemically, and then typed down, using PCR, Gel electrophoresis, and Sanger Sequencing by Genewiz. Antibiotic susceptibility testing was done by modified Kirby-Bauer disc diffusion method and interpretation was done following Clinical and Laboratory Standard Institute (CLSI) guidelines. ESBL screening was done by the phenotypic method, using the standard disk diffusion method, whereas the phenotypic confirmation of ESBL producers was done by the double-disk synergy method, and interpreted according to CLSI guidelines. Multiplex PCR was used to detect the genes for SHV and CTX-M while conventional linear PCR was done for TEM and blas GES type ESBL genes. Results: A total of 77 isolates were identified as Klebsiella pneumoniae, and the prevalence of positive ESBL in them were 10(12.9%). Of the 77 isolates that were tested for antibiogram, 29 isolates were multidrug-resistance (MDR). Out of the MDR isolates, 10 were ESBL positive, whereas 19 were not. Of this 29 MDR isolates, 6 were extensively-drug resistant (XDR). Of the 6 XDR isolates, 3 do not possess ESBL enzymes, whereas 3 of them do. Age range of 31-40 contributed the highest prevalence of ESBL genes (60%), whereas age range of 10-20, 21-30, and 51-70 did not produce any ESBL gene. bla TEM gene was the most prevalent ESBL resistant genes with a prevalence of 10 (100%), followed by SHV 9(90%), whereas bla GES gene and bla CTX-M have the least prevalence of 4 (40%) each. Conclusion: Higher prevalence of MDR, XDR, and ESBL-producing Klebsiella pneumoniae were observed, thus the need for public health intervention for effective prevention and control of antimicrobial resistance, and proper treatment of UTIs.

Possible Acquisition of ESBL-mediated Antimicrobial Resistance by Farmers from Aquatic Reservoir used for Bathing and Cleaning of Water Buffalos (Bubalus bubalis) with Intestinal Carriage of ESBL Producing Escherichia coli

Little information is available on the risk of human subjects for acquisition of antimicrobial resistance (AMR) from aquatic environment other than those treated with antimicrobials for aquaculture. Carriage of extended-spectrum beta-lactamase (ESBL) and carbapenemase categories of AMR by enteric bacteria in livestock have been frequently reported. Dissemination of these categories of AMR to the environment thus poses a threat for their transmission to farmers engaged in livestock care posing a severe public health hazard. A study on the prevalence of ESBL- and carbapenemase-mediated AMR among Escherichia coli isolated from earth pond environment used for bathing and cleaning of buffalos (Bubalus bubalis) and from human subjects engaged in such activity revealed isolation rate of ESBL positivity to be higher in human subjects engaged in washing and bathing of buffalos (37.5%) compared to those without engagement in such activities (20.7%) with CTX-M type ESBL, a group of class A ESBL, as the predominant molecular type (97.4%). While no carbapenemase positivity could be detected among E. coli isolated from pond environment or buffalos, small percentage of carbapenemase could be detected among the E. coli isolated from human subjects although the risk was not higher than those not associated with bathing and cleaning of buffalos. Bathing and cleaning of buffalos could potentially facilitate transmission of ESBL resistance from livestock to human subjects in pond environment.

Molecular Study of Klebsiella Oxytoca Associated with Urinary Tract Infection in Children

Background:There are scarce reports about the association ofKlebsiella oxytoca(K. oxytoca) with urinary tract infection (UTI) in children. We aimed to evaluate the prevalence offimA, mrkA, matBandpilQadhesins genes and extended-spectrum beta-lactamase (ESBL) genesblaCTX-M, blaTEMandblaSHVby polymerase chain reaction (PCR) and to study biofilm formation and antibiotics resistance inK. oxytocafrom children with UTI.Methods:This study was a retrospective cross-sectional study that included 120 children with UTI due toK. oxytoca. The bacteria were subjected to molecular detection offimA, mrkA, matBandpilQadhesins genes and ESBL genesblaCTX-M, blaTEMandblaSHVby PCR. Biofilm capacity was determined by the microtiter plate method.Results:The isolatedK. oxytocahad positive ESBL activity in 45.8% of isolates. About 40% of isolates were biofilm producers. The frequency of adhesion genes amongK. oxytocawas 91.7%, 83.3%, 48.3% and 37.5% formatB, pilQ, fimAandmrkAgenes, respectively. For ESBL genes, the frequency was 38.3%, 36.7% and 33.3% forblaCTX-M, blaSHVandblaTEMgenes, respectively. The commonest genes among ESBL isolates wereblaCTX-M(83.6%),blaSHV(80%) thenblaTEMgene (72.7%). A significant association (p=0.048) was detected between ESBL activity and biofilm formation byK. oxytoca.Conclusion:Present study highlights the emergence ofK. oxytocaas a pathogen associated with UTI in children. There was a high prevalence of adhesin genes and ESBL genes among these isolates. The capacity ofK. oxytocato form biofilm was associated with ESBL production.

A comparative study of VITEK-2, Double Disc Synergy and Combined Disc Methods for detection of ESBL (Extended Spectrum Beta-Lactamase) production in Escherichia coli and Klebsiella pneumoniae strains

Aim: In this prospective study we aimed to compare the effectiveness of VITEK-2 (bioMérieux, France) automated system, double-disc synergy (DDST) versus combined disc test (CDT) in detecting the Extended-Spectrum Beta-Lactamase (ESBL) positivity in Escherichia coli and Klebsiella pneumoniae strains isolated from various clinical samples. Material and Method: E.coli and K. pneumoniae strains inoculated on Mueller Hinton Agar plate. Susceptibility tests were performed with the VITEK 2 (BioMérieux, France) system before. Afterward, EBSL positivity was investigated manually DDST and CDT. Minimal inhibitor concentration (MIC) results of three tests were compared with each other according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST) criteria. Results: 184 E. coli and K.pneumoniae strains, elevated. 92.9% of 98 patients with VITEK 2 positive results were positive with combined disc and DDS method, 100% of the 86 patients with negative results of VITEK 2 were negative with combined disc and MDC. Conclusion: VITEK 2 was found to have a sensitivity of 100%, a specificity of 92.4%, a positive predictive value of 92.8% and a negative predictive value of 100%. VITEK 2 was found to be compatible with validation tests for ESBL positivity.

Increasing rates of extended-spectrum B-lactamase-producing Escherichia coli and Klebsiella pneumoniae in uncomplicated and complicated acute pyelonephritis and evaluation of empirical treatments based on culture results.

Increasing rates of extended-spectrum beta-lactamase (ESBL) producing E. coli and K. pneumoniae over time made empirical treatment complicated. Knowing local antimicrobial resistance patterns of common pathogens can make it easier to decide on empirical antibiotics. We aimed to investigate the prevalence and risk factors of ESBL positivity of E. coli and K. pneumoniae strains in uncomplicated and complicated pyelonephritis acquired in community and healthcare associations and to evaluate the appropriateness of empirical treatment. Adult patients hospitalized with diagnosis of community-acquired or healthcare-associated uncomplicated/complicated pyelonephritis initiated empirical antimicrobial therapy were included in the study. Appropriateness of empirical treatment at 48-72h based on culture resultsand treatment modifications were evaluated. A total of 369 uncomplicated (94) and complicated (275) episodes of pyelonephritis were evaluated. The most common agents wereE. coli(71.0%) andK. pneumoniae(17.7%),and the ESBL-production rate was 64.4%, and higher in healthcare-associated pyelonephritis (P 0.013). Being of healthcare-associated infection, previous antibiotic use, and presence of urinary catheters were independent risk factors for ESBL-producing E. coli and K. pneumoniae (P 0.009, < 0.001, and 0.024, respectively). The treatment inappropriateness was mostly associated with use of ceftriaxone (56.3%) (P < 0.001). Treatment has escalated in 41.5% of ceftriaxone-initiated patients, in only 8.8% and 9.5% ertapenem and piperacillin-tazobactam-initiated patients, respectively. ESBL-production rates are quite high even in community-acquired infections. The use of broad-spectrum antibiotics covering ESBL-producing pathogens to increase the appropriateness of empirical treatment and then narrowing treatment based on culture results appears a better and life-saving choice.

Molecular characterization of multiresistant enterobacteria in two departments of the Peruvian jungle

ResumenIntroducción. La aparición de enterobacterias multirresistentes y productoras de betalactamasas de espectro extendido (BLEE) en pacientes de consulta externa con infecciones urinarias, representa un problema de salud pública en Perú.Objetivos. Caracterizar molecularmente enterobacterias multirresistentes aisladas de pacientes con diagnóstico de infección urinaria y procedentes de dos departamentos de la selva peruana.Materiales y métodos. Se hizo un estudio descriptivo, observacional y retrospectivo de 61 aislamientos de urocultivo procedentes de la selva peruana durante 2017 y 2018. Los perfiles de resistencia se identificaron utilizando el sistema automatizado MicroScan™ y para la detección de los genes bla TEM , bla CTX-M , bla SHV se empleó una reacción en cadena de la polimerasa (PCR) convencional.Resultados. Las enterobacterias positivas para BLEE más frecuentes por departamento fueron Escherichia coli en Madre de Dios (25%, 10/40) y Ucayali (76,2%, 16/21). En ambos departamentos, el gen blaCTX-M fue el más frecuente (25/61; 41), seguido por bla TEM (15/61; 24,6%) y bla SHV (10/61; 16,4%). En el perfil de sensibilidad antimicrobiana, se detectó 72,6% de resistencia contra ampicilina, 82,3 % contra cefalotina y 88,7% contra nitrofurantoína.Conclusiones. El porcentaje de cepas de enterobacterias multirresistentes productoras de BLEE en ambos departamentos fue del 57,4% y el gen bla CTX-M fue el más frecuente.

Phenotypic and Molecular Detection of Resistance Genes from Multi-drug Resistant Escherichia coli Isolated from Patients Attending Selected Hospitals in Damaturu, Yobe State, Nigeria

Multidrug resistance among Escherichia coli causing urinary tract infections (UTIs) and diarrhea are major public health problem worldwide which cause difficulty in treating the infections caused by Escherichia coli due to the high resistances. The study is aimed to determine the phenotypic and molecular detection of multidrug resistant E. coli isolated from clinical samples of patients attending selected Hospitals in Damaturu, Yobe State-Nigeria. Methods: Two hundred (200) clinical samples were collected aseptically from patient diagnosed with (100 stool samples) and UTI’s (100 urine samples) using sterile universal container. The samples were processed using standard microbiological methods for identification of E. coli. Samples were cultured on MacConkey agar (stool) and Cystine lactose electrolyte deficient agar (urine). The resulting colonies of isolates were further subculture on Eosin methylene blue agar for confirmatory and followed by gram stain, biochemical identification at Microbiology laboratory unit of Yobe State Specialist and Yobe State Teaching Hospital respectively. The antimicrobial susceptibility patterns were determined using Kirby-Bauer disc diffusion techniques and the phenotypic expression of extended spectrum beta-lactamases (ESBLs) were determined using modified double disc synergy test (MDDST) and also the three (3) resistance genes (blaTEM, accC1 and qnrA) were detected using polymerase chain reaction. Results: One hundred and twenty-two (122) isolates were resistant to antibiotics. The highest level of resistance was against amoxicillin (90.2%) while the least resistance was against sparfloxacin (24.3%). Thirty-seven (37) E. coli isolates shows MDR; the highest MDR was (24.3%) while least MDR was (5.4%). The PCR amplification of resistant genes (blaTEM, accC1 and qnrA) were detected on E. coli that shows positive ESBL and the bands were separated using agarose gel electrophoresis. Conclusion: The findings of this study show augmentin, ciprofloxacin and sparfloxacin are the most effective antibiotics against E. coli isolated from patients attending the two hospitals in Damaturu; who are diagnose with UTI and diarrheic infection. The resistant genes include; blaTEM, accC1 and qnrA coding for beta-lactam, aminoglycoside and quinolones were present in E. coli isolated from patients attending selected Hospitals in Yobe State, Nigeria. Keywords: Multidrug resistant, Escherichia coli, extended spectrum beta lactamase, resistance-associated genes, urinary tract infections, diarrheic.

Antibiotic Susceptibility Pattern of Extended-Spectrum Beta-Lactamase-Producing Klebsiella Pneumoniae and Escherichia Coli

Extended-Spectrum Beta-Lactamase (ESBL) producing bacteria is a type of resistance that leads to complex management of patients in intensive care due to their resistance to first, second, and third-generation Cephalosporin and monobactam antibiotics. The most ESBL-producing bacteria are found in the family Enterobacteriaceae, especially Klebsiella pneumoniae and Escherichia coli. The purpose of this research was to determine the sensitivity pattern of ESBLproducing bacteria in Intensive Care Units (ICUs) of Ulin Hospital, Banjarmasin, in the period of 2016-2018. This research was a descriptive study with a cross-sectional approach using data from the laboratory medical records of patients with positive ESBL in the ICUs of Ulin Hospital, Banjarmasin, between 2016 and 2018. The research sample was taken by the total sampling method. This research obtained 216 isolates of ESBL-producing bacteria consisting of 155 (71.8%) isolates of Klebsiella pneumoniae and 61 (28.2%) Escherichia coli. It was found that the Cephalosporin antibiotics (Cefazolin, Ceftazidime, Ceftriaxone, and Cefepime) and monobactam antibiotic (Aztreonam) had the lowest sensitivity. Aminoglycoside antibiotics (Amikacin), Carbapenem (Ertapenem and Meropenem), and Tetracycline (Tigesycline) were the most sensitive antibiotics. It was concluded that both Klebsiella pneumoniae and Escherichia coli were the most dominant ESBL-producing bacteria and showed good sensitivity to the Amikacin, Ertapenem, Meropenem, and Tigecycline.

Bacteria Causing Community-Acquired Urinary Tract Infections and Their Antibiotic Susceptibility Patterns in Outpatients Attending at a State Hospital in Turkey

IntroductionClinicians should know the frequency and resistance patterns of bacteria that cause urinary tract infections (UTI) to provide patients with appropriate treatment and antibiotic management. However, the frequency of culture reproducing organisms and resistance patterns change in each community. Therefore, these data must be determined locally to make better treatment decisions. Herein, we aimed to determine the frequency of UTI-causing agents and current antimicrobial resistance profiles in outpatients attending our hospital.MethodsThis retrospective descriptive study included three hundred eight outpatients attending under the diagnosis of UTI between March and October 2020 who had a positive urine culture for bacterial growth. Age, sex, laboratory tests, urinalysis results, microorganisms grown in urine culture, and antibiograms were evaluated from the patients' medical records. Data were analyzed using SPSS version 23.0 (IBM Corp., Armonk, NY) for Windows.ResultsIn urine culture results, Escherichia coli (E. coli) and Klebsiella species are the most commonly detected agents. The growth in 71 (23%) of the 308 cultures was extended-spectrum beta-lactamase (ESBL) positive. In the E. coli growths, the susceptibility rates to fosfomycin, gentamicin, nitrofurantoin, trimethoprim-sulfamethoxazole, and ampicillin were 95.2%, 90.3%, 95.3%, 76.8%, and 49.3%, respectively. The susceptibility of Klebsiella species to gentamicin was as high as 93.7%, similar to that of E. coli, whereas its susceptibility rates to fosfomycin, trimethoprim-sulfamethoxazole, and nitrofurantoin were lower than those of E. coli (76.1%, 48.4%, and 68.4%, respectively). Of the 71 ESBL-positive growths, 52 were E. coli (17.3% of all UTIs), and 14 were Klebsiella species (4.6% of all UTIs). Of the ESBL-positive strains, 88.7%, 81%, and 76.1% were susceptible to fosfomycin and nitrofurantoin, respectively, and 64.9% and 45.7% were sensitive to cefoxitin and trimethoprim-sulfamethoxazole.ConclusionUTIs are among the most common causes of hospital admission and infections for which empirical antibiotic administration is initiated. The increasing rates of ESBL positivity and resistance to antibiotics such as ampicillin, cephalosporins, trimethoprim-sulfamethoxazole, and quinolones, especially in E. coli and Klebsiella strains, which are the most common pathological agents of UTI in our region, have limited the use of these treatments. However, the high susceptibility of E. Coli growths to fosfomycin and nitrofurantoin and susceptibility of Klebsiella growths to gentamicin may make these antibiotics stand out as suitable options for the empirical treatment of UTI in our setting.

Acute Kidney Injury is A Risk Factor among Type 2 Diabetic Patients after UTI due to Extended-Spectrum Beta-Lactamase Producing Organisms

Background: Urinary tract infections (UTIs) are very communal, and patients with diabetics develop UTIs more frequently. Acute kidney injury (AKI) can be a complication of UTI. This study is designed to determine whether Urinary tract infections because of extended-spectrum beta-lactamase (ESBL) could be a risk factor of acute kidney injury in individuals with type-II diabetes mellitus. Methods: This case study was conducted in the Outpatient department of Diabetes Hospital Peshawar and Nishter Hospital Multan for duration of six months from August 2020 to January 2021. People of type II diabetes were assessed with culture confirmed UTI. The cases of UTI patients complicated with AKI were included in the study group, and people without AKI were taken as a control group. ESBLs positivity from isolated organisms have been assessed as risk factors for AKI. A total of 140 subjects were selected with equal distribution in two groups. The group A has UTI complicated with AKI and group B included has patients without AKI but with UTI. Results: UTI was diagnosed in 140 cases among type-II diabetic patients with 2:4 male to female ratio. The duration and mean age of diabetes mellitus were 8.60±5.35and55.80±14.10 years, correspondingly. The strongest common etiological factor was Escherichia coli (60.7%), trailed by Klebsiella pneumoniae (11.4%). In ESBL positive organism; E. coli was present in 81.4% and K. pneumoniae in 10% of individuals. Of the 140 UTI cases, AKI was observed in 70 (50%); out of which 48 (62.5%) were ESBL-positive microorganisms and 22 (22/70, 31.43%) for non-ESBL microorganisms. Conclusions: Nearly50% of the patients with type-II diabetes mellitus and UTI had ESBL-positive microorganisms as etiological mediators in this analysis. Owing to the presence of ESBL-positive microorganisms, UTI was the main cause of AKI and is a strong risk factor. Keywords: ESBL, Acute kidney injury, UTI, type 2 diabetes, risk factor.

Identifikasi Extended Spectrum Beta Laktamase (ESBL) Antibiotika Golongan Sefalosporin pada Bakteri Acinetobacter baumannii

Extended Spectrum Beta-Lactamases (ESBL) are group of enzymes that break down the antibiotics of penicillin and cephalosporin group,this enzymes made bacteria are resistant to this type of antibiotic. Acinetobacter baumannii is one of the gram-negative bacteria, produce the ESBL enzyme. Globally, Acinetobacter baumannii has become a nosocomial pathogen that continues to increase in frequency. The prevalence of ESBL of Acinetobacter spp in Indonesia is 19-29% which is resistant to the third and fourth generation cephalosporin antibiotics. This study uses an experimental laboratory design with consecutive sampling techniques. Acinetobacter baumannii was isolated from 50 patients. The isolate comes from sputum, pus, blood, urine, endotrackeal (ETT), pleural fluid, bronchial rinses and stool. Samples of isolates were identified using standard bacteriological methods and the Vitek 2 Compact ® system using a GN card. Tests carried out include antimicrobial sensitivity tests performed using the Kirby-Bauer diffusion method and ESBL production test using the Double Disc Synergy Test (DDST) and Phenotypic Confirmatory Test. The results showed that the bacterium Acinetobacter baumannii was successfully isolated from all samples with an accuracy level (91% - 99%). In the antimicrobial sensitivity test it was found that of the 50 clinical samples tested against antibiotics cephalosporin group, which had experienced resistance in the largest sequence were Cefotaxime 22 samples (44%), Ceftazidime 20 samples (40%), Ceftriaxone 20 samples (40%) and Cefepime 19 samples (38%). In the ESBL production test found 9 samples (18%) positive ESBL in ceftazidime + As.Klavulanat antibiotics, 9 samples (18%) positive ESBL in cefotaxime + As.Klavulanat antibiotics (30 ?g / 10 ?g).&#x0D; Keywords: Cephalosporin antibiotics, Acinetobacter baumannii, Resistance, Extended Spectrum Beta Lactamase (ESBL)&#x0D;

1267. Comparative activity of omadacycline against extended-spectrum beta-lactamase positive and negative Escherichia coli and Klebsiella pneumoniae strains recovered from urine specimens

BackgroundOmadacycline (OMC) is a novel tetracycline (TET) derivative antibiotic with activity against TET-resistant Enterobacterales. OMC is available in both oral and intravenous formulations and is has been studied as a treatment of uncomplicated urinary tract infection (UTI) and acute pyelonephritis. The purpose of this study was to evaluate OMC activity against extended-spectrum beta-lactamase (ESBL) positive and negative Enterobacterales strains recovered from urine specimens.MethodsUrine samples from patients with suspected UTI were quantitatively plated onto blood agar and MacConkey agar plates in the microbiology lab of Wake Forest Baptist Medical Center. After overnight incubation, colonies were identified to the species level by MALDI-TOF system. Susceptibility testing was performed for isolates of E. coli and K. pneumoniae. OMC and TET susceptibility testing was performed by disk diffusion and gradient strip methodologies. Results were interpreted in accordance with the Clinical and Laboratory Standards Institute (CLSI) or Food and Drug Administration breakpoints. Isolates were tested in triplicate. ESBL screening and susceptibility testing to oral antibiotics commonly prescribed for UTI were performed by the MicroScan WalkAway System. Susceptibility rates and MIC50/90 were calculated and subsets of isolates were analyzed using descriptive statistics.ResultsA total of 204 isolates, including 102 E. coli and 102 K. pneumoniae, were tested. All but 1 isolate (99.5%) exhibited categorical agreement in results generated by the strip (Table 1) and disk (data not shown) methods and this was considered a minor error involving an intermediate result. OMC MIC90 for E. coli and K. pneumoniae were 6 µg/mL and >32 µg/mL, respectively. OMC displayed increased susceptibility rates compared to TET regardless of isolate species or ESBL positivity (Table 2).Table 1. Omadacycline Minimum Inhibitory Concentrations (MICs, µg/mL) Table 2. Susceptibilities of Oral Antibiotics Used to Treat UTI (% S) ConclusionOMC exhibits promising antimicrobial activity against TET-resistant and ESBL-positive E. coli and K. pneumoniae. OMC displays superior activity to ESBL positive E. coli when compared to ESBL positive K. pneumoniae. These data support the development of OMC as a much needed option in the treatment of UTI caused by resistant Enterobacterales.Disclosures Tyler J. Stone, PharmD, Paratek (Research Grant or Support) Abdullah Kilic, MD, Paratek (Grant/Research Support) John Williamson, PharmD, Paratek (Research Grant or Support) Elizabeth Palavecino, MD, Paratek (Grant/Research Support)Paratek (Grant/Research Support)