Extended-Spectrum Beta-lactamase and Metallo-beta-lactamase Production among Escherichia coli and Klebsiella pneumoniae Strains from Urine of Pregnant Women in Afikpo, Ebonyi State, Nigeria

Aim: The aim of this study was to determine the occurrence of Extended-spectrum beta-lactamase (ESBL) and Metallo-beta-lactamase (MBL) among Escherichia coli and Klebsiella pneumoniae strains from pregnant women attending Mater Misericordia Hospital Afikpo, Ebonyi state, Nigeria. Study Design: This is a laboratory based prospective study carried out on pregnant women suspected of having urinary tract infection and was requested to undergo diagnosis at microbiology laboratory of the hospital. Place and Duration of Study: The study was conducted in the Department of Science Laboratory Technology, Akanu Ibiam Federal Polytechnic, Unwana, Afikpo, Ebonyi State, Nigeria from October, 2022 to January, 2023. Methodology: Clean-catch midstream urine samples were collected from 206 pregnant women suspected of having urinary tract infection and were requested to undergo medical diagnosis at microbiology laboratory of the hospital. The urine samples were processed following standard microbiological procedure. Antimicrobial susceptibility testing was determined using the disc diffusion method, while ESBL phenotypes were determine by the Double-Disc Synergy Test (DDST). Disc potentiation test was performed to check for MBL production. Results: Out of the 206 urine samples processed, 24 (11.7 %) E. coli and 12 (5.8 %) K. pneumoniae were isolated. The antimicrobial susceptibility of the isolates recorded a 100 % resistance with Amoxicillin/Clavulanic acid and Cotrimoxazole. The Gram-negative isolates showed a high sensitivity of 100 % to Netilmicin, Meropenem and Ofloxacin. Overall, 35 (97.2 %) multidrug resistance (MDR) was observed of the bacteria isolates. A total of 9 (37.5 %) E. coli and 4 (33.3 %) K. pneumoniae was found positive for ESBL production whereas, 5 (20.8 %) E. coli and 2 (16.7 %) K. pneumoniae were MBL positive. Conclusion: The level of drug resistance in this study underscores the need for regular surveillance for effective management of urinary tract infection in pregnancy.

Risk factors for extended-spectrum beta-lactamase- and carbapenem- resistant Enterobacteriaceae in patients with urinary tract infection from a tertiary care hospital

Background: Urinary tract infection (UTI) is a common health problem in both community and nosocomial settings. However, the predisposing factors which are responsible for production of extended spectrum beta-lactamase (ESBL) and carbapenem-resistant Enterobacteriaceae makes the treatment option narrow and cause multidrug resistance. Aim and Objectives: This study demonstrate various risk factors associated with multidrug resistance in Enterobacteriaceae from UTI at tertiary care center in Gujarat. Material and Methods: A retrospective observational study was conducted at a tertiary-care hospital. Urine samples were received from various departments and outpatient department (OPD). Organisms from Enterobacteriaceae group were isolated and identified by various biochemical methods. ESBL and Carbapenemase producing organisms were then processed for Antibiotic susceptibility test as per CLSI guideline. Results: A total of 196 Enterobacteriaceae organisms were isolated from processed urine samples of tertiary care Hospitals. The most prevalent in people aged 45–65 years (36%) followed by those aged 17–30 (22%) years. UTI due to ESBL and Carbapenemase producer are more isolated in female (28%, 11%) as compare to male (16%, 6%). Indoor patients had higher prevalence of ESBL (29%) and carbapenemases (10%) isolation compare to OPD patient (ESBL-15%, Carbapenemases-7%) and among them most common ward was medicine department. The most common predisposing factor was catheterization followed by diabetes mellitus and obstructive uropathy. Conclusion: High prevalence of ESBL and Carbapenemase producing Enterobacteriaceae is found in Indoor patients than OPD patients. Most of these patients are from Medicine department. Catheterization is the most common risk factor associated with ESBL and carbapenemase producing organism.

Detection and correlation of antimicrobial resistance pattern in Enterobacteriaceae from UTI patients in GMERS Medical College, Gujarat

Background: Bacterial resistance to antibiotics is a growing public health threat worldwide. The increasing rate of antimicrobial resistance among bacterial pathogens causing both hospital- and community-acquired infections is a serious threat to public health world-wide. This inappropriate and non-judicious usage of antibiotics has resulted in the development of worldwide antibiotic resistance in bacteria, leading to the emergence of multi-resistant strains of bacterial pathogens. This study focuses on the prevalence of antibiotic resistance in the Enterobacteriaceae group of organisms in urine samples and also detects various methods of antibiotic resistance. Antibiotic resistance detection may be useful for epidemiological and research purposes, as well as for preventing the spread of drug-resistant organisms within hospitals through good infection control practices. Aims and Objectives: The aim of the study was to detect occurrence of ?-lactamases, extended-spectrum beta-lactamases (ESBL) and Carbapenemase by phenotypic methods in Enterobacteriaceae from urine samples along with pattern of antibiotic resistance for various antibiotics in them. Materials and Methods: A descriptive study was conducted at a tertiary-care hospital. Testing of ESBL and carbapenemase production detection done according to CLSI (M100) guideline by the Kirby-Bauer disk diffusion method, combination disc diffusion test, and modified Carbapenem inactivation method. Results: A total of 220 Enterobacteriaceae organisms were isolated from processed urine samples of tertiary care Hospitals. Rate of cephalosporin resistance in ESBL and carbapenem-resistant Enterobacteriaceae (CRE) is more than 90% while in non-ESBL more than 70% and in non-CRE 75–80%. Carbapenem resistance in ESBL and non-ESBL is the same. Resistance to fluoroquinolone group, Aminoglycoside group, and Cotrimoxazole and Tetracycline group of antibiotics were more noticed in ESBL and carbapenemase producing organisms. In our study, fosfomycin and Nitrofurantoin are effective treatment in case of ESBL and CRE producing organism. Conclusion: The ESBL and Carbapenemase producing isolates were multi-drug resistant making therapeutic choices limited. Fosfomycin and Nitrofurantoin are effective treatment in multidrug resistance urinary tract infection.

Characterization of third generation cephalosporin-resistant Escherichia coli clinical isolates from Ushuaia, Argentina / Caracterización de aislamientos clínicos de Escherichia coli resistente a cefalosporinas de tercera generación de Ushuaia, Argentina

Abstract Escherichia coli is one of the main human pathogens causing different hospital- and community-acquired infections. During the period from January 2013 to March 2015, 1.96% (32/1632) of E. coli isolates recovered at the Hospital Regional de Ushuaia, Tierra del Fuego province, were resistant to third-generation cephalosporins (TGCs). These isolates were resistant to cefotaxime (91%) and/or ceftazidime (28%). No resistance to carbapenems was detected. Twenty-six isolates were positive for blaCTX-M gene, grouped as CTX-M-1/15 (54%); CTX-M-9/14 (25%); CTX-M-2 (17%); and CTX-M-1/15 plus CTX-M-9/14 (4%). Five TGC-resistant strains were positive for blaCMY gene, while one strain harbored TEM-19 ESBL. Twelve isolates were identified as ST131 E. coli hyperepidemic clone, and one as ST69. Genome sequence analysis of seven blaCTX-M-15 E. coli selected isolates confirm the circulation of ST131, ST617 and ST405 international high-risk clones in the city of Ushuaia.

Resumen Escherichia coli es uno de los principales patógenos humanos causantes de diferentes infecciones de inicio hospitalario y comunitario. Se determinó que el 1,96% (32/1.632) de los aislamientos de E. coli recuperados entre enero de 2013 y marzo de 2015 en el Hospital Regional de Ushuaia, provincia de Tierra del Fuego, fueron resistentes a cefalosporinas de tercera generación (CTG). Estos aislamientos fueron resistentes a cefotaxima (91%) y/o a ceftazidima (28%). No se detectó resistencia a los carbapenemes. Veintiséis aislamientos fueron positivos para el gen blaCTX-M, agrupados como CTX-M-1/15 (54%), CTX-M-9/14 (25%), CTX-M-2 (17%) y CTX-M-1/15 más CTX-M-9/14 (4%). Cinco cepas resistentes a CTG dieron positivo para el gen blaCMY, mientras que un aislamiento presentó la BLEE TEM-19. Doce aislamientos se identificaron como clon hiperepidémico E. coli ST131 y uno como ST69. El análisis de las secuencias del genoma de siete aislamientos seleccionados de E. coli blaCTX-M-15 confirmó la circulación de los clones internacionales de alto riesgo ST131, ST617 y ST405 en la ciudad de Ushuaia.

Risk factors for ESBL-positive Escherichia coli urinary tract infections / Factores de riesgo para infección urinaria por Escherichia coli BLEE positiva

Abstract Objective: to determine the association of prior antibiotic use, prior hospitalizations, prior urinary tract infections, age, sex and comorbidities in adult patients hospitalized with urinary tract infections caused by extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli. Materials and methods: a case-control study carried out in the hospital setting of private clinics in Lima. Thirty cases and 30 controls were included, with cases defined as hospitalized patients with an ESBL-producing E. coli urinary tract infection diagnosed by urine culture, and controls defined as hospitalized patients without ESBL-producing E. coli infection. Data were taken from incident cases. A bivariate analysis was performed followed by multivariate logistic regression using the significant variables from the bivariate analysis. Results: the associated factors were: prior antibiotic use OR: 261 (22.5-11,017.4), prior hospitalization OR: 4.6 (1.39-16.1), and prior urinary tract infection OR: 36 (6.9-227.2). After adjusting for potential confounding factors using logistic regression, the main statistically significant associated factor was prior antibiotic use, OR: 97.7 (8.4-1,128.3, p<0.000). Conclusion: evidence was found that prior antibiotic use is a risk factor significantly associated with ESBL E. coli urinary tract infections. (Acta Med Colomb 2022; 47. DOI:https://doi.org/10.36104/amc.2022.2131).

Resumen Objetivo: establecer la asociación del uso previo de antibióticos, hospitalizaciones previas, infección urinaria previa, edad, sexo y comorbilidades en pacientes adultos hospitalizados con infección urinaria por Escherichia coli productora de beta lactamasas de espectro extendido (BLEE). Material y métodos: estudio caso control, realizado en clínicas privadas de Lima en ámbito hospitalario. Se incluyeron 30 casos y 30 controles, definiéndose como caso al paciente hospitalizado que cuente con diagnóstico de infección urinaria por urocultivo de E. coli productora de BLEE y como control al paciente hospitalizado sin infección por E. coli BLEE. Se recolectó la información de casos incidentes. Se realizó un análisis bivariado y regresión logística multivariable con las variables que fueron significativas en el análisis bivariado. Resultados: los factores asociados fueron: uso previo de antibióticos OR: 261 (22.5-11017.4), hospitalización previa OR: 4.6 (1.39-16.1), infección urinaria previa OR: 36 (6.9-227.2). Al ajustar por variables potencialmente confusoras mediante regresión logística, se observó que el principal factor asociado con significación estadística fue el uso previo de antibióticos, OR: 97.7 (8.4-1128.3, p<0.000). Conclusión: se encontró evidencia de que el uso previo de antibióticos es un factor de riesgo asociado significativamente a infección urinaria por E. coli BLEE. (Acta Med Colomb 2022; 47. DOI:https://doi.org/10.36104/amc.2022.2131).

Inhibition of Carbapenem-Resistant NDM-1 Klebsiella pneumoniae isolated from a Hospital Outbreak Patient by a Synbiotic: A Nonantibiotic Treatment Option

Objective: Klebsiella (K.) pneumoniae is globally responsible for an alarming increase in hospital infections, especially in intensive care units (ICUs). The acquisition of resistance against a broad range of antibiotics has turned infections with this pathogen into a major worldwide healthcare concern. The aim of the study was to investigate if multistrain synbiotics can complement the current treatment options of multidrug-resistant K. pneumoniae infections. Methods: Antimicrobial susceptibility and PCR testing were used to characterize the K. pneumoniae causing a hospital outbreak. Effect of multistrain synbiotic administration on the presence of K. pneumoniae in an infected patient was investigated by microbiological testing for the pathogen. Effects of the synbiotic mixture and its individual probiotic bacteria on K. pneumoniae isolated from patients and of the K. pneumoniae subsp. pneumoniae ATCC© 700603TM reference strain were investigated by pathogen in-vitro inhibition experiments. Results: The outbreak K. pneumoniae strain was found to be resistant against a range of antibiotics including carbapenems, and to be a producer of New Delhi metallo-β-lactamase 1 (NDM-1). Treatment of a NDM-1 K. pneumoniae carrier with a multistrain synbiotic resulted in successful elimination of the pathogen from the patient. In-vitro inhibition experiments showed that the NDM-1 K. pneumoniae (and the reference strain K. pneumoniae subsp. pneumoniae, ATCC© 700603TM) could be effectively inhibited by the bacteria mixture of the synbiotic preparation. Conclusion: Findings of the study indicate for the first time that a multistrain synbiotic can add to the treatment repertoire available for the management of NDM-1 K. pneumoniae infections.

In vitro screening of multidrug resistance uropathogenic Escherichia coli from the urban area of Namakkal district

The aim of the study is to screen the multiple drug resistance (MDR) Uropathogenic Escherichia coli (UPEC) fromthe urban area of Namakkal district. To detect UPEC resistant by using different antibiotics and to analyze the virulentcharacteristics of UPEC and amplification of extended-spectrum beta-lactamases genes by multiplex polymerasechain reaction. Total 450 samples individually collected from the urinary tract infection (UTI) patients’ and directstreaked on to the eosin methylene blue agar plates. Significant growth indicates E. coli. HiCrome UTI agar was usedfor rapid identification of uropathogenic E. coli. Out of 450 samples, only 62 isolates of E. coli were subjected tovirulence characteristics, such as slime production (34%), hemolytic activity (56%), and beta-lactamase production(43%). Antibiotic sensitivity test was performed with 13 different antibiotics. Among them, 62 isolates were E. coli,only five were resistant to 10 antibiotics, possess virulence characteristics. Four strains (E-12, E23, E-58, and E-97)have Temoneira, sulfhydryl variable, and cefotaxime hydrolyzing capabilities (CTX-M) antibiotic resistance genes,and E-07 have only CTX-M gene. As E. coli is the main infectious agent in patients with UTI and a potent pathogen,it was difficult to treat with routine antibiotics because day-by-day microbes are resisting to common drugs. Hence,they need alternative therapy

Biliary tract infections and their Microbiological Spectrum- A study from coastal region of Southern India / Infecciones de vías biliares y su espectro microbiologico- Un estudio en región de la costa del sur de la India

Objective: Biliary tract infections include cholangitis and cholecystitis. They are associated with high morbidity and mortality in elderly patients with co-morbid disease. The present study was undertaken to determine the microbial aetiology causing biliary tract infections and also to study their antimicrobial resistance profile. Materials & methods: A retrospective study was conducted from January 2011 to December 2016 at the Enteric Diseases Division, Kasturba Medical College Hospital, Manipal. Patients with biliary tract infections admitted in tertiary referral health care hospital, Manipal were included for the study. Aerobic and anaerobic bacteriological and fungal aetiology of biliary tract infections were recorded along with their antimicrobial resistance profile. Results: Out of 307 bile samples sent for aerobic culture and susceptibly testing 187 (60.91%) were positive for culture, of which Escherichia coli (44.4%) was the predominant aetiology followed by Klebsiella pneumoniae (27.3%). Among the 14 samples sent for anaerobic culture, 5 (35.75%) specimens showed growth, of which Bacteroides fragilis group was found to be the predominant anaerobe. Among the 201 bacterial pathogens tested for their antimicrobial susceptibility, 108 (53.73%) isolates were resistant, out of which 9 were PDR Enterobacteriaceae with 12 ESBL strains. All the Candida species were susceptible to fluconazole with the exception of C. glabrata and C. krusei. All the anaerobic isolates were found to be susceptible to Metronidazole. Conclusions: The high rate of bacterial infection particularly gram-negative bacteria was recorded. It is necessary that antimicrobial therapy be initiated when culture or the clinical conditions reports caution. Routine aerobic and anaerobic culturing of bile samples with biliary tract infections are imperatively necessary. With the emergence of multidrug resistant pathogens and change in the microbiological spectrum of biliary tract infections, there is a need for the empirical antimicrobial therapy in every clinical setting.

Objectivo: Las infecciones del tracto biliar incluyen colangitis y colecistitis. Se asocian a gran mortalidad y morbildiad en pacientes ancianos y con comorbilidad. El presente studio se hizo para detemrianr la etiologia microbiana que produce infecciones biliares y para estudiar su perfil de resistencia antimicrobiana. Materiales & metodos: Se hizo un studio retrospectivo entre los meses de Enero 2011 a Diciembre de 2016 en la "Enteric Diseases Division, Kasturba Medical College Hospital, Manipal" en India. Los pacientes con infección de vías biliares admitidos al centro de atención de tercer nivel se incluyeron en el estudio. Se buscaron bacterias aerobicas y anaerobicas y etiologia fungica y se analizó su perfil de resistencia antibiotica. Resultados: De 307 muestras de bilis enviadas para cultivo aerobico y antibiograma, 187 (60.91%) crecieron en el medio de cultivo, predominando Escherichia coli (44.4%) seguida por Klebsiella pneumoniae (27.3%). Entre las 14 muestras analizadas en medio anaerobio, 5 (35.75%) mostraron crecimiento de Bacteroides fragilis. Entre 201 bacterias probadas por antibiograma, 108 (53.73%) tuvieron perfil de resistencia, de los cuales 9 fueron PDR Enterobacteriaceae con 12 cepas ESBL. Todas las especies de Candida fueron susceptibles al fluconazol con la excepción de C. glabrata y C. krusei. Todos los aislados anaerobios fueron susceptibles al Metronidazol. Conclusiones: Se encontró una alta tasa de infección bacteriana con predominio de gram-negativos. Se hace necesario iniciar terapia antimicrobiana cuando lo sugieren las condiciones clínicas o el resultado del cultivo. El cultivo rutinario de bilis es imperioso. Dado el aumento de patógenos multirresistentes se requiere inicio empírico inmediato

Perfil de sensibilidad de Escherichia coli aislados de infecciones del tracto urinario de pacientes del Hospital Regional de Villarrica en el periodo de julio 2013 a agosto 2015 / Sensitivity profile of Escherichia coli isolated from urinary tract infections of patients of the Regional Hospital of Villarrica from July 2013 to August 2015

Introducción: El uso inapropiado de los antimicrobianos está conduciendo a la disminución de la sensibilidad antimicrobiana de microorganismos que producen enfermedades infecciosas. El uso clínico de los antimicrobianos ha sido paralelo al surgimiento de bacterias resistentes a su acción. Materiales y Métodos: Se realizó un estudio observacional, descriptivo, retrospectivo de corte transversal, con muestreo no probabilístico de casos consecutivos. La selección de antibióticos incluyó solo aquellos que tienen actividad frente a bacilos gram negativos y para la interpretación de los diámetros de los halos de inhibición se tomaron en cuenta los estándares de la Clinical and Laboratory Standards Institute (CLSI versión 2015). Resultados: La ampicilina presentó una resistencia del 100%, en cambio la ciprofloxacina presentó una sensibilidad del 73%, la amikacina del 100% y la gentamicina del 82%. La familia de los carbapenemicos presentó una sensibilidad del 100%. Dentro del grupo de los nitrofuranos se constató una sensibilidad del 96%. El trimetoprim/ sulfametoxazol, presentó una sensibilidad del 57%. Se determinó la presencia de Beta Lactamasa de Espectro Extendido (BLEE) en 13% de las cepas de Escherichia coli estudiadas. Conclusiones: La gentamicina, la nitrofurantoína y los carbapenemes presentaron una elevada sensibilidad, por lo que en presencia de cepas con BLEE serían opciones factibles acompañados siempre de la evaluación del perfil renal y clasificando la ITU como complicada o no.

Introduction: The inappropriate use of antimicrobials is leading to a decrease in the antimicrobial sensitivity of microorganisms that cause infectious diseases. The clinical use of antimicrobials has been parallel to the emergence of bacteria resistant to its action. Materials and methods: The sensitivity profile of Escherichia coli isolated from patients with urinary tract infections (UTI) concurrent to the Regional Hospital of Villarrica in the period from 2013 to 2015 was determined. Results: Ampicillin showed a resistance of 100%, ciprofloxacin showed a sensitivity of 73%. Amikacin showed a sensitivity of 100% and gentamicin 82%. The family of carbapenem showed a sensitivity of 100%. Within the group of nitrofurans a sensitivity of 96% was found. Trimethoprim / sulfamethoxazole had a sensitivity of 57%. The presence of Extended Spectrum Beta Lactamase (ESBL) was determined in 13% of the strains of Escherichia coli studied. Conclusions: Gentamicin, nitrofurantoin and carbapenem have a high sensitivity, so in the presence of strains with ESBL they would be feasible options always accompanied by the evaluation of the renal profile and classifying the UTI as complicated or not.

Contribution of acrB upregulation & OmpC/Ompk36 loss over the presence of blaNDM towards carbapenem resistance development among pathogenic Escherichia coli & Klebsiella spp.

Background & objectives: The global spread of carbapenem-resistant Enterobacteriaceae (CRE) is an emerging clinical problem. Hence, in this study, the plausible role of extended-spectrum beta-lactamases (ESBLs)/carbapenemases, OmpC/Ompk36, acrB and their combinations was explored among CRE. Methods: The minimum inhibitory concentration (MIC) of meropenem, enzyme-phenotypes (ESBLs/IR and metallo-beta-lactamase (MBL)/non-MBL carbapenemase), genotypes (blaTEM, blaSHV and blaCTX-M; blaNDM and blaVIM; blaKPC and blaOXA-48-like variants), acrB and outer membrane protein (OMP) expressions were analyzed with a total of 101 non-duplicate clinical isolates, obtained from various samples of patients visiting two tertiary care units of Eastern India during May 2013 - October 2016. This included Escherichia coli (n=36) and Klebsiella pneumoniae (n=65), categorized into two groups, namely Group I (resistant to all carbapenems; n=93; E. coli=34 and Klebsiella spp.=59) and Group II (non-resistant to all the carbapenems; n=8; E. coli=2 and Klebsiella spp.=6). Results: Though 88.17 per cent of Group I isolates exhibited ESBL property, the presence of carbapenemase activity (70.96%) and that of blaNDM gene (42/66: 63.63%) indicated their contributions towards the emergence of CRE. Further, porin loss and/or efflux pump activation among ESBL/carbapenemase-producing isolates heightened the MIC of meropenem from 64 to 256 mg/l (range exhibited by only ESBL/carbapenemase-producing isolates) to >256 mg/l. Interpretation & conclusions: These findings implied the major contribution of porin loss and/or efflux pump activation over the presence of ESBLs/carbapenemases in imparting carbapenem resistance in pathogenic bacteria.

Molecular epidemiology and mechanisms of fosfomycin-resistant Escherichia coli producing extended-spectrum β-lactamases isolated from urine / 临床检验杂志

Objective@#To investigate the molecular epidemiology and mechanisms of fosfomycin-resistant Escherichia coli isolates producing extended-spectrum β-lactamases (ESBLs) isolated from urine. @*Methods@#Fosfomycin-resistant phenotypes were screened by drug susceptibility test in ESBLs-producing E.coli stains. The ESBLs gene and fosfomycin resistant gene were amplified by PCR. The molecular typing was analyzed by multiple sequence type (MLST). The transferability of the drug resistant gene was verified by conjugation assays. @*Results@#Among the 308 strains of E.coli isolated from urine, there were 168 (54.54%) ESBLs producing strains and 18 (10.71%, 18/168) fosfomycin resistant strains. In the drug resistant genes, the incidence of bla SHV was about 88.9% (16/18), bla CTX-M was 77.8% (14/18), bla TEM-208 was 5.6% (1/18), bla TEM-1b was 61.1% (11/18) and fosA3 was 83.3% (15/18). The main MLST genotype was ST131. The conjugation test confirmed the transferability of resistance in fosA3 positive strain. @*Conclusion@#The fosfomycin resistant rate of ESBLs producing E.coli in urethral infection was in a low level. The fosA3 gene was the main mechanism of fosomycin resistance and located on the conjugation plasmids, which should be the main node of horizontal gene transmission. We need to pay great attention to this resistant gene.

Clinical Prediction Score for Community-Onset Bloodstream Infections Caused by Extended-Spectrum Beta-Lactamase-Producing Escherichia coli and Klebsiella Species

BACKGROUND: This study aimed to identify the predictors and build a prediction score for community-onset bloodstream infections (CO-BSIs) caused by extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli and Klebsiella species. METHODS: All CO-BSIs caused by E. coli and Klebsiella species from 2012 to 2015 were grouped into derivation (BSIs from 2012 to 2014) and validation (BSIs in 2015) cohorts. A prediction score was built using the coefficients of the multivariate logistic regression model from the derivation cohort. RESULTS: The study included 886 CO-BSIs (594 and 292 in the derivation and validation cohorts, respectively). The independent predictors of CO-BSIs caused by ESBL-producing E. coli and Klebsiella species included: 1) identification of ESBL-producing microorganisms from any clinical culture within one year of admission, 2) beta-lactam or fluoroquinolone treatment within 30 days (with 2 or more courses within 90 days; with 1 course within 90 days), 3) hospitalization within one year, 4) the presence of an indwelling urinary catheter at the time of admission. The area under the curve (AUC) of the clinical prediction score was 0.72 (95% confidence interval [CI], 0.68–0.77). In the validation cohort, the AUC was 0.70 (95% CI, 0.63–0.77). CONCLUSIONS: The results of this study suggest a simple and easy-to-use scoring system to predict CO-BSIs caused by ESBL-producing E. coli and Klebsiella species.

Carbapenem Resistance in Gram-negative Bacteria in South-western Nigeria: The Role of Extended-spectrum lactamase CTX-M-15 / Resistencia al carbapenem en las bacterias gramnegativas en Nigeria Suroccidental: papel de la betalactamasa de espectro extendido tipo CTX-M-15

ABSTRACT Objective: To determine the role of extended-spectrum β-lactamases in carbapenem-resistant Gram-negative bacteria from south-western Nigeria. Methods: Twenty-seven carbapenem-resistant isolates that were found to be non-carbapenemase producers (15 Escherichia coli, 9 Klebsiella pneumoniae and 3 Pseudomonas aeruginosa) were further studied. These isolates were subjected to analysis including phenotypic and genotypic detection of various β-lactamases, efflux activity, outer membrane protein, plasmids replicon typing, detection of transferable genes and resistances and typing using random amplified polymorphic DNA tests. Results: No isolates demonstrated de-repression of efflux, but all showed either complete loss or reduced production of outer membrane proteins. Transconjugants from these strains contained various genes including plasmid-mediated quinolone resistance and extended-spectrum beta-lactamases. All the transconjugants carried the blaCTX-M-15 gene. The transconjugants had varying minimum inhibitory concentrations of carbapenems ranging from 0.03 μg/ml to 8 μg/ml. Varying resistances to other antimicrobial agents were also transferred with the plasmids. The donor isolates were not clonally related by molecular typing. Conclusion: Resistance to carbapenem antibiotics in this sample was not mediated only by carbapenemases but also by production of extended-spectrum β-lactamases (largely CTX-M-15), accompanied by protein loss. This was an important mechanism underpinning carbapenem resistance in these clinical isolates of various species.

RESUMEN Objetivo: Determinar el papel de las betalactamasas de espectro extendido en la resistencia al carbapenem en las bacterias gramnegativas en Nigeria. Métodos: Veintisiete aislados resistentes al carbapenem que fueron hallados productores de no carbapenemasas (15 Escherichia coli, 9 Klebsiella pneumoniae, y 3 Pseudomonas aeruginosa) fueron estudiados con mayor profundidad. Estos aislados fueron sometidos a análisis incluyendo la detección fenotípica y genotípica de varias betalactamasas, la actividad de eflujo, las porinas de la membrana externa, la tipificación del replicón plasmídico, la detección de genes transferibles y resistencias y tipificación usando pruebas de ADN polimórficas amplificadas aleatorias. Resultados: Ninguno de los aislamientos mostró desrepresión de eflujo, pero todos demostraron la pérdida completa o la producción reducida de porinas externas de la membrana. Los transconjugantes de estas cepas contenían varios genes incluyendo resistencia a la quinolona mediada por plásmidos y betalactamasas de espectro extendido. Todos los transconjugantes portaban el gen blaCTX-M-15. Los transconjugantes tenían diversas concentraciones inhibitorias mínimas de carbapenemas que oscilaban entre 0.03 μg/ml y 8 μg/ml. Varias resistencias a otros agentes antimicrobianos fueron también transferidas con los plásmidos. Los aislamientos del donante no estuvieron relacionados clonalmente por tipificación molecular. Conclusión: La resistencia al antibiótico carbapenem en esta muestra no fue mediada solamente por las carbapenemasas, sino también por la producción de betalactamasas de espectro extendido (en gran parte CTX-M-15), acompañado por pérdida de porina. Éste era un mecanismo importante que sustentaba la resistencia al carbapenem en estos aislados clínicos de varias especies.

Características y factores de riesgo de la infección de vías urinarias con cultivo positivo para betalactamasas de espectro extendido en adultos atendidos en urgencias en el Hospital Militar Central / Clinical characteristics and risk factors for urinary tract infection with extended spectrum betalactamase infections in the emergency service of the Central Military Hospital

Objetivo: El objetivo del estudio fue describir los factores de riesgo de los pacientes adultos con infección de vías urinarias (IVU) por enterobacterias productoras de betalactamasas de espectro extendido (BLEE) en la población usuaria del Hospital Militar Central (HMC) los años 2012 y 2014. Se analizaron factores de riesgo como hospitalización previa, residente en unidad de cuidado crónico, uso previo de antibióticos, uso previo de esteroides, instrumentación del tracto urinario y usuario de sonda vesical. Materiales y métodos: Se realizó un estudio de casos y controles, retrospectivo, la fuente de información fueron las historias clínicas de los pacientes adultos mayores de 18 años de edad, que consultaron al servicio de urgencias del HMC, con diagnostico de IVU por una enterobacteria productora de BLEE. Se establecieron las características de la muestra y se determinó cuales fueron los factores de riesgo asociados al desarrollo de la infección por gérmenes productores de BLEE en la muestra seleccionada. Resultados: De los 1986 aislamientos que cumplían los criterios de selección, 14% correspondían a microorganismos productores de BLEE. De los seis factores de riesgo estudiados, tres presentaron una diferencia estadísticamente significativa: la hospitalización previa, el uso previo de antibióticos y la instrumentación del tracto urinario. De los factores de riesgo identificados, se realizó un análisis multivariado donde se mantuvieron como factores de riesgo significativos el uso previo de antibióticos y la instrumentación del tracto urinario que aumentan el riesgo de IVU por gérmenes productores de BLEE en 1,9 y 3,18 veces respectivamente. Conclusiones: Si bien los otros factores de riesgo descritos no alcanzaron una diferencia estadísticamente significativa, se deben realizar estudios prospectivos para poder evaluar su asociación con el desarrollo de infecciones por gérmenes resistentes y así desarrollar una escala de riesgo que permita al personal de urgencias administrar antibioticoterapia dirigida para este subgrupo poblacional.

Objectives: The objective of the study was to describe the risk factors of adult patients with urinary tract infection (UTI) with extended spectrum beta-lactamase producing bacteria (ESBL) in the population of the Hospital Militar Central (HMC) in 2012 and 2014. Risk factors such as previous hospitalization, chronic care unit resident, previous use of antibiotics, previous use of steroids, urinary tract instrumentation and bladder catheter were analyzed. Material and methods: We conducted a retrospective case-control study, the source of information were the medical records of adult patients older than 18 years of age, who consulted the emergency department of the HMC, diagnosed with UTI by a bacterium carrying ESBL. The characteristics of the sample were established and the risk factors associated with the development of infection by ESBL-producing bacteria in the selected sample were determined. Results: Of the 1986 isolates that fulfilled the selection criteria, 14% reported microorganisms producing ESBL. Of the six risk factors studied, three presented a statistically significant difference: previous hospitalization, previous use of antibiotics and urinary tract instrumentation. Of the risk factors identified, a multivariate analysis was performed in which the previous use of antibiotics and urinary tract instrumentation were maintained as significant risk factors that increase the risk of UTI by ESBL-producing bacterias in 1,9 and 3,18 times respectively. Conclusions: Although the other risk factors described did not reach a statistically significant difference, prospective studies should be performed to assess their association with the development of resistant germ infections and to develop a risk scale that allows emergency personnel to administer targeted antibiotic therapy to this population subgroup.

Failure of Ciprofloxacin Therapy in the Treatment of Community-Acquired Acute Pyelonephritis caused by In-Vitro Susceptible Escherichia coli Strain Producing CTX-Type Extended-Spectrum β-Lactamase / 감염과화학요법

While carbapenems are the drug of choice to treat extended-spectrum-β-lactamase (ESBL)-producing strains, some alternative carbapenem-sparing regimens are suggested for antibiotic stewardship. We experienced a case of ciprofloxacin treatment failure for acute pyelonephritis caused by an apparently susceptible Escherichia coli. A 71-year-old woman presented the emergency department with fever for 7 days and bilateral flank pain for 2 days. The laboratory results and abdominopelvic computed tomography finding were compatible with acute pyelonephritis. During 3-day ciprofloxacin therapy, the patient remained febrile with persistent bacteremia. After the change in antibiotics to ertapenem, the patient’s clinical course started to improve. ESBL-producing E. coli isolates were identified in all three consecutive blood samples. Pulsed-field gel electrophoresis (PFGE) patterns, serotypes, and sequence types showed the three isolates were derived from the identical strain. The isolates produced CTX-M-14 type ESBL belonging to the ST69 clonal group. Despite in vitro susceptibility, the failure was attributed to a gyrA point mutation encoding Ser83Leu within quinolone resistance-determining regions. This case suggests that ciprofloxacin should be used cautiously in the treatment of serious infections caused by ciprofloxacin-susceptible, ESBL-producing E. coli, even in acute pyelonephritis because in-vitro susceptibility tests could fail to detect certain genetic mutations.

Failure of Ciprofloxacin Therapy in the Treatment of Community-Acquired Acute Pyelonephritis caused by In-Vitro Susceptible Escherichia coli Strain Producing CTX-Type Extended-Spectrum β-Lactamase / 감염과화학요법

While carbapenems are the drug of choice to treat extended-spectrum-β-lactamase (ESBL)-producing strains, some alternative carbapenem-sparing regimens are suggested for antibiotic stewardship. We experienced a case of ciprofloxacin treatment failure for acute pyelonephritis caused by an apparently susceptible Escherichia coli. A 71-year-old woman presented the emergency department with fever for 7 days and bilateral flank pain for 2 days. The laboratory results and abdominopelvic computed tomography finding were compatible with acute pyelonephritis. During 3-day ciprofloxacin therapy, the patient remained febrile with persistent bacteremia. After the change in antibiotics to ertapenem, the patient’s clinical course started to improve. ESBL-producing E. coli isolates were identified in all three consecutive blood samples. Pulsed-field gel electrophoresis (PFGE) patterns, serotypes, and sequence types showed the three isolates were derived from the identical strain. The isolates produced CTX-M-14 type ESBL belonging to the ST69 clonal group. Despite in vitro susceptibility, the failure was attributed to a gyrA point mutation encoding Ser83Leu within quinolone resistance-determining regions. This case suggests that ciprofloxacin should be used cautiously in the treatment of serious infections caused by ciprofloxacin-susceptible, ESBL-producing E. coli, even in acute pyelonephritis because in-vitro susceptibility tests could fail to detect certain genetic mutations.

Detection of multidrug-resistant Pseudomonas aeruginosa harboring bla GES-1 and bla GES-11 in Recife, Brazil

Abstract INTRODUCTION: Pseudomonas aeruginosa, an important pathogen globally, presents several resistance mechanisms. This study aimed to investigate the presence of bla GES in clinical isolates of Pseudomonas aeruginosa obtained from various clinical specimens from patients admitted to three different hospitals in Recife, Brazil. The Guiana extended spectrum beta-lactamase (GES) enzymes are responsible for conferring broad spectrum resistance to beta-lactam drugs, including the carbapenems. METHODS: A total of 100 carbapenem-resistant P. aeruginosa isolates underwent polymerase chain reaction (PCR) testing to identify bla GES, bla KPC, bla SPM-1, bla IMP, and bla VIM. Additionally, PCR products positive for bla GES were sequenced. The clonal profiles of these same isolates were then determined by means of enterobacterial repetitive intergenic consensus (ERIC)-PCR analysis. RESULTS: PCR analysis revealed that four isolates harbored bla GES; DNA sequencing showed that two harbored bla GES-1 and two bla GES-11. Beta-lactamase genes bla SPM-1, bla IMP, bla VIM, and bla KPC were investigated; none of these genes was detected. Automated susceptibility testing methods (Vitek®2, bioMérieux) showed that the bla GES-1-positive isolates were only susceptible to polymyxin B. The patterns obtained with ERIC-PCR methods showed clonal relationship between the two isolates that harbored bla GES-11, whereas different clonal profiles were found in the isolates harboring bla GES-1. CONCLUSIONS: We detected the presence of bacterial isolates positive for two different variants of the enzyme GES in three different hospitals from Recife, Brazil. These enzymes have a great capacity for dissemination among Gram-negative bacteria and confer broad-spectrum resistance to beta-lactam antibiotics and to the carbapenems.

Colonización rectal por bacilos gram negativos multirresistentes: importancia de la detección precoz durante la hospitalización / Rectal colonisation by multiresistant gram-negative bacilli: relevance of early detection in the course of hospitalization / Colonização retal por bacilos gram negativos multirresistentes: importância da identificação precoce durante a hospitalização

Las infecciones asociadas con el cuidado de la salud son consideradas un problema epidémico, controlable pero difícilmente erradicable. La detección precoz de pacientes colonizados por microorganismos multirresistentes, a través de cultivos de vigilancia epidemiológica y la implementación de medidas preventivas pueden reducir su incidencia. El objetivo del trabajo fue establecer los momentos adecuados durante la hospitalización para realizar estudios de colonización y decidir los microorganismos a estudiar según el lugar de procedencia del paciente. Se analizaron hisopados rectales de pacientes internados en la Unidad de Terapia Intensiva, obtenidos al ingreso, a las 72 h y al sexto día de internación. Se investigó Acinetobacter spp multirresistente (AMR), enterobacterias productoras de BLEE (EB-BLEE) y de KPC (EB-KPC). Los resultados mostraron 15,2% de pacientes de la comunidad y 16,7% de geriátricos colonizados con EB-BLEE al ingreso. Dicho porcentaje fue mayor (28,6%) en pacientes previamente institucionalizados y, además, 2,6% colonizados con EB-KPC y 3,4% con AMR. Los controles posteriores mostraron porcentajes crecientes de portación con el transcurso de la internación. Por lo tanto, es importante la detección de estos microorganismos al ingreso hospitalario y continuar con vigilancia activa, para poder implementar medidas precoces tendientes a evitar las consecuencias de la rápida transmisión horizontal.

Healthcare associated infections are considered an epidemic problem; manageable but difficult to eradicate. The early detection of patients infected with antimicrobial multiresistant microorganisms by means of epidemiological surveillance cultures and the execution of prophylactic measures, are key to reduce their incidence. The aim of this work was to assess a suitable schedule in the course of hospitalisation to perform colonisation studies and to decide which microorganisms to analyse according to the provenance of the patient. Rectal swabs from patients admitted at the Intensive Care Unit obtained at the time of admission, 72 h and six days later were analysed. Multiresistant Acinetobacter spp.(MRA), ESBL- and KPC- producing Enterobacteriaceae (ESBL-EB and KPC-EB, respectively) were investigated. Results showed that 15.2% of patients without previous hospitalisation and 16.7% of patients coming from geriatric institutions were colonised by ESBL-EB at the moment of admission. This percentage was greater (28.6%) in previously hospitalised patients, of whom 2.6% were found to be colonized by KPC-EB and 3.4% by MRA. Subsequent monitoring showed increasing colonisation percentages with the course of hospitalisation. Therefore, detection of these microorganisms at the time of admission and constant active surveillance are crucial to implement early measures aiming to avoid the consequences of rapid horizontal dissemination.

As infecções relacionadas ao cuidado da saúde são consideradas um problema epidêmico controlável, mas dificilmente erradicável. A identificação precoce em pacientes colonizados por microorganismos multirresistentes, através de culturas de vigilância epidemiológica e a implementação de medidas preventivas, podem diminuir sua incidência. O objetivo do trabalho foi estabelecer os momentos adequados durante a hospitalização para realizar testes de colonização e decidir quais os microorganismos que serão estudados de acordo com o lugar de procedência do paciente. Foram testados Swabs retais de pacientes internados na Unidade de Terapia Intensiva (UTI), coletados ao serem admitidos, nas 72h e no sexto dia de internação. Foram analisados Acinetobacter spp. multirresistente (AMR), enterobactérias produtoras de BLEE (EB-BLEE) e de KPC (EB-KPC). Os resultados mostraram 15.2% de pacientes da comunidade e 16.7% de geriátricos colonizados com EB-BLEE ao serem admitidos. Ese percentual foi maior (28.6%) em pacientes previamente institucionalizados e, além disso, 2.6% colonizados com EB-KPC e 3.4% com AMR. Os controles posteriores mostraram percentuais crescentes de portação com o decorrer da internação. Portanto, é importante a identificação destes microorganismos no momento da admissão hospitalar e continuar com a vigilância ativa, para poder implementar medidas precoces tendentes a evitar as consequências da rápida transmissão horizontal.

Detección de Betalactamasas de espectro extendido en Enterobacteriaceae en un Centro de Salud de Maracaibo, Venezuela / Detection of Extended-Spectrum ß-lactamase-producing Enterobacteriaceae in a Healthcare Center from Maracaibo city, Venezuela

La alta incidencia de las enfermedades infecciosas y el aumento de la resistencia a los antibióticos se han convertido en la actualidad en un problema de salud pública, siendo las enterobacterias productoras de Betalactamasas de Espectro Extendido (BLEE) un ejemplo de este fenómeno. En el presente estudio se determinó la producción de BLEE en aislados clínicos de la familia Enterobacteriaceae procedentes de una institución de salud de la ciudad de Maracaibo, durante el periodo septiembre de 2014 a febrero de 2015. Para la detección de BLEE se utilizó como método preliminar el de Kirby-Baüer, siguiendo los lineamientos del CLSI; adicionalmente se utilizó como prueba confirmatoria fenotípica el método de sinergia del doble disco y como prueba confirmatoria genotípica la detección de los genes blaCTX-M, blaTEM y blaSHV mediante PCR. Se analizaron 55 enterobacterias productoras de BLEE, distribuidas de la siguiente manera: Escherichia coli 56,36%, Klebsiella pneumoniae 21,82%, Enterobacter cloacae 7,27%, Proteus mirabilis y Serratia marcescens 5,45% para cada especie, por último, Salmonella spp. y Morganella morganii 1,82% respectivamente. En cuanto al tipo de BLEE detectado mediante PCR, se observó que el 83,63% de los aislados presentó el tipo TEM, seguido de CTX-M (23,63%) y SHV (21,81%), mientras que el 27,27% de los aislados produjo dos o tres BLEE de manera simultánea. Los resultados de este estudio confirman la alta diseminación de este mecanismo de resistencia entre las enterobacterias productoras de infecciones en nuestras instituciones públicas de salud, por lo que deben aplicarse medidas de control que permitan controlar y disminuir su incidencia.

The high incidence of the infectious diseases and the antimicrobial resistance arise represent a public health threat today. The extended-spectrum ß-lactamase (ESBL)-producing Enterobacteriaceae are an example of this phenomenon. We determined the ESBL-production in Enterobacteriaceae isolates from a Healthcare Center in Maracaibo, during September 2014 to February 2015. The Kirby-Baüer method was perform to preliminary phenotypic detection of ESBL, according to CLSI guidelines. ESBL-production was confirmed by a double-disk synergy test according to the CLSI standards. To genotypic confirmation, the genes blaCTX-M, blaTEM and blaSHV were amplified by PCR. Fifty-five (n=55) strains were analyzed distributed in Escherichia coli (56.36 %), Klebsiella pneumoniae (21.82 %), Enterobacter cloacae (7.27 %), Proteus mirabilis and Serratia marcescens (5.45 % each one), Salmonella spp. and Morganella morganii (1.82 % each one). The major encoded ESBL was the blaTEM gene (83.63 %); followed by 23.63% of the blaCTX-M gene, and 21.81 % encoded the blaSHV gene. 27.27 % of the isolates produced two or three ESBL simultaneously. These results confirmed the high spread of this resistant mechanism among Enterobacteriaceae-producing infections in our public health institutions, therefore control measures should applied to control and reduce its incidence.

Escherichia Coli productora de Nueva Delhi metalo-ß-lactamasa en Colombia: reporte de caso / Escherichia Coli producing New Delhi metallo-ß-lactamase in Colombia: A case report

Notificamos un caso de infección por Escherichia coli productora de Nueva Delhi metalo-b-lactamasa (NDM) en un paciente que desarrolló un absceso subcapsular hepático como complicación de una colecistectomía laparoscópica. La NDM es una carbapenemasa adquirida tipo Ambler B, que confiere resistencia a todos los b-lactámicos, excepto al aztreonam, aunque existen reportes de resistencia a este último. En Colombia, la primera descripción de cepas productoras de NDM se realizó en aislamientos de Klebsiella pneumoniae en una unidad de cuidados intensivos neonatales en Bogotá. Desde entonces se han realizado reportes de distintas cepas, siendo esta la primera reportada en el país relacionada con Escherichia coli productora de NDM.

We report a case of infection by New Delhi metallo-β-lactamase (NDM)-producing Escherichia coli in a patient who developed a subcapsular hepatic abscess as a complication of laparoscopic cholecystectomy. NDM is an acquired carbapenemase Ambler class B, which confers resistance to all b-lactams except aztreonam, although there are reports of resistance to the latter. In Colombia, the first report of NDM-producing strains was made on isolates of Klebsiella pneumoniae in a neonatal intensive care unit in Bogota. There have since been reports of different strains, marking the first reported in the country of NDM-producing Escherichia coli.