Genetic profile and characterization of antimicrobial resistance in Acinetobacter baumannii post-COVID-19 pandemic: a study in a tertiary hospital in Recife, Brazil.

AIMS: To investigate the genetic profile and characterize antimicrobial resistance, including the main ß-lactam antibiotic resistance genes, in Acinetobacterbaumannii isolates from a tertiary hospital in Recife-PE, Brazil, in the post-COVID-19 pandemic period. METHODS AND RESULTS: Acinetobacter baumannii isolates were collected between 2023 and 2024 from diverse clinical samples. Antimicrobial resistance testing followed standardized protocols, with ß-lactamase-encoding genes detected via PCR and sequencing. Investigation into ISAba1 upstream of blaOXA-carbapenemase and blaADC genes was also conducted. Genetic diversity was assessed through ERIC-PCR. Among the 78 A. baumannii, widespread resistance to multiple antimicrobials was evident. Various acquired ß-lactamase-encoding genes (blaOXA-23,-24,-58,-143, blaVIM, and blaNDM) were detected. Furthermore, this is the first report of blaVIM-2 in A. baumannii isolates harboring either the blaOXA-23-like or the blaOXA-143 gene in Brazil. Molecular typing revealed a high genetic heterogeneity among the isolates, and multi-clonal dissemination. CONCLUSION: The accumulation of genetic resistance determinants underscores the necessity for stringent infection control measures and robust antimicrobial stewardship programs to curb multidrug-resistant strains.

Whole-Genome Analysis of Extensively Drug-Resistant Enterobacter hormaechei Isolated from a Patient with Non-Hodgkin's Lymphoma.

BACKGROUND: Currently, the Enterobacteriaceae species are responsible for a variety of serious infections and are already considered a global public health problem, especially in underdeveloped countries, where surveillance and monitoring programs are still scarce and limited. Analyses were performed on the complete genome of an extensively antibiotic-resistant strain of Enterobater hormaechei, which was isolated from a patient with non-Hodgkin's lymphoma, who had been admitted to a hospital in the city of Manaus, Brazil. METHODS: Phenotypical identification and susceptibility tests were performed in automated equipment. Total DNA extraction was performed using the PureLink genomic DNA mini-Kit. The genomic DNA library was prepared with Illumina Microbial Amplicon Prep and sequenced in the MiSeq Illumina Platform. The assembly of the whole-genome and individual analyses of specific resistance genes extracted were carried out using online tools and the Geneious Prime software. RESULTS: The analyses identified an extensively resistant ST90 clone of E. hormaechei carrying different genes, including blaCTX-M-15, blaGES-2, blaTEM-1A, blaACT-15, blaOXA-1 and blaNDM-1, [aac(3)-IIa, aac(6')-Ian, ant(2″)-Ia], [aac(6')-Ib-cr, (qnrB1)], dfrA25, sul1 and sul2, catB3, fosA, and qnrB, in addition to resistance to chlorhexidine, which is widely used in patient antisepsis. CONCLUSIONS: These findings highlight the need for actions to control and monitor these pathogens in the hospital environment.

Antimicrobial resistance and associated risk factors in Escherichia coli isolated from Peruvian dogs: A focus on extended-spectrum ß-lactamases and colistin.

Background and Aim: Established antimicrobial resistance (AMR) surveillance in companion animals is lacking, particularly in low-middle-income countries. The aim of this study was to analyze AMR and its risk factors in Escherichia coli isolated from dogs at two veterinary centers in Lima (Peru). Materials and Methods: Ninety dogs were included in the study. Antimicrobial susceptibility was established by disk diffusion, whereas microdilution was used to determine colistin susceptibility. Mechanisms related to extended-spectrum ß-lactamases (ESBL) and colistin resistance were determined by polymerase chain reaction. Clonal relationships of colistin-resistant isolates were assessed by XbaI-pulsed-field gel electrophoresis. Results: Thirty-five E. coli strains were isolated. High levels of resistance to ampicillin (57.1%), nalidixic acid (54.3%), tetracycline (48.6%), and azithromycin (25.7%) were detected. Cephalosporin resistance levels were ≥20% and those for colistin were 14.3%. Twelve (34.2%) isolates were ESBL producers; of these, six blaCTX-M-55 (50.0%), 2 (16.6%) blaCTX-M-15, and 2 (16.6%) blaCTX-M-8-like genes were found. The five colistin-resistant isolates were clonally unrelated, with four of them presenting amino acid codon substitutions in the mgrB gene (V8A) or mutations in the mgrB promoter (a12g, g98t, and c89t). Furthermore, dog age, <6 years (p = 0.027) and raw diet (p = 0.054) were associated with resistance to a greater number of antibiotic families. Conclusion: Despite small number of samples included, the study found that dogs studied were carriers of multidrug-resistant E. coli, including last-resort antimicrobials, representing a public health problem due to close contact between dogs and humans. This issue suggests the need for larger studies addressed to design strategies to prevent the spread of resistant micro-organisms in small animal clinics and domestic settings.

Prevalence and characteristics of ESBL-producing Escherichia coli in clinically healthy pigs: implications for antibiotic resistance spread in livestock.

AIM: This study aimed to compare and characterize the resistance profile and the presence of extended-spectrum beta-lactamase (ESBL) related genes in Escherichia coli isolated from healthy finishing pigs fed with or without antibiotics in their diets. METHODS AND RESULTS: A total of 27 ceftiofur-resistant E. coli isolates were obtained from 96 healthy pigs. The antibiotic resistance profile was tested, and all 27 isolates were classified as multidrug-resistant (MDR). A high proportion of isolates were resistant to cephalosporins, ampicillin, ciprofloxacin, and tetracyclines. The ESBL production was observed in 85% of isolates by double-disc synergy test. The MDR-E. coli isolates harbored ESBL genes, such as blaTEM, blaCTX-M-1, blaCTX-M-2, and blaCTX-M-8,25. In addition, other antibiotics resistance genes (ARGs) were also detected, such as sul2, ant(3″)-I, tetA, and mcr-1. The mobilization of the blaCTX-M gene was confirmed for nine E. coli isolates by conjugation assays. The presence of blaCTX-M on mobile genetic elements in these isolates was demonstrated by Southern blot hybridization, and the resistance to cephalosporins was confirmed in the transconjugants. Our results indicate the prevalence of CTX-M-producing E. coli strains harboring mobile genetic elements in the normal microbiota of healthy pigs. CONCLUSIONS: These findings highlight the significance of ESBL genes as a global health concern in livestock and the potential spread of antimicrobial resistance to other members of the gastrointestinal tract microbiota.

Clinical outcomes of intensive care unit patients infected with multidrug-resistant gram-negative bacteria treated with ceftazidime/avibactam and ceftolozane/tazobactam.

In intensive care units (ICUs), infection rates range from 18 to 54%, which is five to ten times higher than those observed in other hospital units, with a mortality rate of 9% to 60%. In recent decades, the susceptibility pattern has changed and Gram-Negative Bacteria (GNB) have become a threat due to their high frequency of multidrug resistance associated with a scarcity of therapeutic options. However, the drugs Ceftolozane/Tazobactam (C/T) and Ceftazidime/Avibactam (C/A) are demonstrating good clinical and microbiological response in the treatment of severe nosocomial infections. Therefore, this study aims to evaluate the clinical outcome of patients with severe infections caused by Multidrug-Resistant (MDR) GNB treated with C/T and C/A. Our study evaluates a total of 131 patients who received treatment with C/T and C/A due to infections caused by MDR GNB within the period from 2018 to 2021. The main infections were urinary tract (46,6%) and respiratory (26,7%) infections. Pseudomonas aeruginosa was the prevailing agent in the sample evaluation (34.3%), followed by Klebsiella pneumoniae (30,1%). About 54,9% of patients showed a favorable response, with culture negativation in 66,4% of the samples, with no discrepancy in negativations when comparing ages: 67,7% in young and 66% in elderly patients. Among the patients, 62,6% received monotherapy with C/T and C/A with a better response observed with monotherapy compared to combination therapy (58,6% vs 41,4%). The overall mortality rate was 45%, with MDR GNB infections responsible for 33,9% of these deaths, and the others (66,1%) due to factors such as oncological, hematological, and degenerative neurological diseases. In regards to hematological aspect, 35,1% of patients showed changes, with 28,2% of them presenting anemia, 4,5% thrombocytopenia, and 2,5% thrombocytosis. Concerning the use of invasive devices, higher mortality was observed in patients on mechanical ventilation (52%). In this manner, it was possible to observe that therapy with C/T and C/A yielded a favorable clinical outcome in patients with severe infections caused by MDR GNB in the study. These drugs also demonstrated good tolerability regardless of age or the presence of preexisting comorbidities and were deemed safe when assessing adverse effects. Our data also demonstrate the importance of determining the mechanism of resistance to carbapenems so that these drugs can be used more effectively and rationally.

Molecular mechanism of antimicrobial co-resistance Colistin (mcr-1) and ESBLs genes among Escherichia coli isolates from commercial chickens in Pakistan / Mecanismo molecular de corresistência antimicrobiana de Colistina (mcr-1) e genes ESBLs entre isolados de Escherichia coli em frangos comerciais no Paquistão

Emergence of plasmid mediated colistin and extended spectrum ß-lactamases (ESBL) resistant genes has been impacted the efficacy of colistin and ß-lactams drugs like 3rd, 4th generation cephalosporin. Current study was aimed to investigate antimicrobial resistance genes (ARGs) among Escherichia coli isolates from meat producing commercial broilers in Pakistan. Two hundred (n=200) fecal samples were collected during January-2018 to August-2019. For isolation of E. coli, pink colonies on MacConkey agar were transferred to EMB agar. Metallic sheen color colonies were tested biochemically using API-20E kit. The molecular identification of E. coli (n=153) was targeted by amplification of uid gene through polymerase chain reaction (PCR) and different ARGs i.e. gentamicin, streptomycin, tetracycline, colistin, ß-lactams drugs, quinolone and ampicillin followed by sequence analysis. Genotypically, followed by phenotypically of resistant ARGs of isolated PCR-confirmed E. coli (153) shoed resistant against gentamicin (aac(3)-IV), streptomycin (aadA1), tetracycline (tetA), colistine (mcr-1), ampicillin (bla-TEM) and bla-CTX-M were 86%, 88%, 86%, 88%, 83% & 77% respectively. 33/38 (86%) of the isolate was positive for quinolone resistance. Colistine (mcr-1), ESBLs (bla-TEM) and (bla-CTX-M) resistance genes were 88%, 83% and 77% respectively. About 33 isolated E. coli harbored the both mcr-1 and ESBLs genes. All of E. coli isolates were found sensitive to ceftriaxone (CTX-30) and imipenem (IMP-10). The Isolated E. coli showed single or multi clade decadency. The E. coli and ARGs sequences showed single or multi clade decadency. This is first comprehensive study from Pakistan that described the molecular evidences of ARGs and their co-existence in single isolates originated from commercial poultry. Commercial chicken (Broilers) can act as melting pot of antibiotic resistance genes for human being. It is alarming situation for surveillance of antibiotic resistance program because of more regulated prescription of antimicrobial agents in Pakistan.

O surgimento de colistina mediada por plasmídeo e genes de resistência a ß-lactamases de espectro estendido (ESBL) afetou a eficácia de medicamentos colistina e ß-lactâmicos, como as cefalosporinas de 3ª e 4ª geração. O presente estudo teve como objetivo investigar genes de resistência antimicrobiana (ARGs) entre isolados de Escherichia coli em frangos de corte comerciais no Paquistão. Duzentas (n = 200) amostras fecais foram coletadas durante janeiro de 2018 a agosto de 2019. Para o isolamento de E. coli, colônias rosas em ágar MacConkey foram transferidas para ágar EMB. As colônias de cores de brilho metálico foram testadas bioquimicamente usando o kit API-20E. A identificação molecular de E. coli (n = 153) foi direcionada pela amplificação do gene uid através da reação em cadeia da polimerase (PCR) e diferentes ARGs, ou seja, gentamicina, estreptomicina, tetraciclina, colistina, medicamentos ß-lactâmicos, quinolona e ampicilina, seguido de análise de sequência. Genotipicamente, seguido por fenotipicamente de ARGs resistentes de E. coli isoladas foram confirmadas por PCR (153) como resistente contra gentamicina (aac(3)-IV), estreptomicina (aadA1), tetraciclina (tetA), colistina (mcr-1), ampicilina (bla-TEM) e bla-CTX-M, demonstrando resultados de 86%, 88%, 86%, 88%, 83% e 77%, respectivamente. Cerca de 33/38 (86%) do isolado foi positivo para resistência às quinolonas. Os genes de resistência à colistina (mcr-1), ESBLs (bla-TEM) e (bla-CTX-M) foram 88%, 83% e 77%, respectivamente. Cerca de 33 E. coli isoladas continham os genes mcr-1 e ESBLs. Todos os isolados de E. coli foram considerados sensíveis à ceftriaxona (CTX-30) e imipenem (IMP-10). A E. coli isolada apresentou decadência de um ou vários clados. As sequências de E. coli e ARGs apresentaram decadência de um ou vários clados. Este é o primeiro estudo abrangente do Paquistão que descreveu as evidências moleculares de ARGs e sua coexistência em isolados únicos originados de aves comerciais. Dessa forma, é possível concluir que o Frango comercial (Broilers) pode atuar como caldeirão de genes de resistência a antibióticos para o ser humano. É uma situação alarmante para a vigilância do programa de resistência a antibióticos devido à prescrição mais regulamentada de agentes antimicrobianos no Paquistão.

Traditional marketed meats as a reservoir of multidrug-resistant Escherichia coli.

This study aimed to analyze Escherichia coli from marketed meat samples in Peru. Sixty-six E. coli isolates were recovered from 21 meat samples (14 chicken, 7 beef), and antimicrobial resistance levels and the presence of mechanisms of antibiotic resistance, as well as clonal relationships and phylogeny of colistin-resistant isolates, were established. High levels of antimicrobial resistance were detected, with 93.9% of isolates being multi-drug resistant (MDR) and 76.2% of samples possessing colistin-resistant E. coli; of these, 6 samples from 6 chicken samples presenting mcr-1-producer E. coli. Colistin-resistant isolates were classified into 22 clonal groups, while phylogroup A (15 isolates) was the most common. Extended-spectrum ß-lactamase- and pAmpC-producing E. coli were found in 18 and 8 samples respectively, with blaCTX-M-55 (28 isolates; 16 samples) and blaCIT (8 isolates; 7 samples) being the most common of each type. Additionally, blaCTX-M-15, blaCTX-M-65, blaSHV-27, blaOXA-5/10-like, blaDHA, blaEBC and narrow-spectrum blaTEM were detected. In addition, 5 blaCTX-M remained unidentified, and no sought ESBL-encoding gene was detected in other 6 ESBL-producer isolates. The tetA, tetE and tetX genes were found in tigecycline-resistant isolates. This study highlights the presence of MDR E. coli in Peruvian food-chain. The high relevance of CTX-M-55, the dissemination through the food-chain of pAmpC, as well as the high frequency of unrelated colistin-resistant isolates is reported.

Phenotypic and genetic screening of Klebsiella pneumoniae isolates from human UTI patients for beta-lactamases and their genetic diversity analysis by ERIC and REP PCRs.

Klebsiella pneumoniae is one of the major nosocomial pathogens responsible for pneumoniae, septicaemia, liver abscesses, and urinary tract infections. Coordinated efforts by antibiotic stewardship and clinicians are underway to curtail the emergence of antibiotic-resistant strains. The objective of the present study is to characterize K. pneumoniae strains through antibiotic resistance screening for production of beta-lactamases (ß-lactamases) such as extended spectrum beta lactamases (ESBLs), AmpC ß-lactamases, and carbapenemases by phenotypic and genotypic methods and genetic fingerprinting by enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) and repetitive element palindromic PCR (REP-PCR). A total of 85 K. pneumoniae strains isolated from 504 human urinary tract infections (UTI) were used in this study. Only 76 isolates showed positive in phenotypic screening test (PST), while combination disc method (CDM) as phenotypic confirmatory test (PCT) confirmed 72 isolates as ESBL producers. One or more ß-lactamase genes were detected by PCR in 66 isolates (91.66%, 66/72) with blaTEM gene being the most predominant (75.75%, 50/66). AmpC genes could be detected in 21 isolates (31.8%, 21/66) with FOX gene being the predominant (24.24%, 16/66), whereas NDM-I was detected in a single strain (1.51%, 1/66). Genetic fingerprinting using ERIC-PCR and REP-PCR revealed wide heterogeneity among ß-lactamase producing isolates with discriminatory power of 0.9995 and 1, respectively.

Characterization of ESBL-producing Escherichia spp. and report of an mcr-1 colistin-resistance Escherichia fergusonni strain from minced meat in Pamplona, Colombia.

Foods of animal origin are increasingly considered a source of extended spectrum ß-lactamase (ESBL) producing bacteria which can disseminate throughout the food chain and become a health concern for humans. This work aimed to evaluate the occurrence of ESBL-producing Escherichia coli in 100 retail minced meat samples taken in markets in Pamplona, Colombia. A total of 19 ESBL-producing isolates were obtained, 18 identified as E. coli and one as E. fergusonii. Fifteen isolates (78.9 %) carried blaCTX-M and blaTEM genes, one (5.2 %) blaSHV and blaTEM genes, one isolate (5.2 %) carried blaCTX-M and one (5.2 %) blaSHV alone. The majority of CTX-M-positive E. coli isolates carried the blaCTX-M-15 gene (13 isolates), being the blaCTX-M-9, blaCTX-M-2, and blaCTX-M-8 (one isolate each) also detected. Two SHV-positive isolates presented the blaSHV-5 and blaSHV-12 allele. The isolate identified as E. fergusonii was positive for blaCTX-M-65 gene and mcr-1 gene. Sixteen isolates (84.2 %) belonged to phylogroups A and B1 and grouped together in the phylogenetic tree obtained by MLST; phylogroups E and F were also detected. Transfer of ESBL resistance was demonstrated for the E. fergusonii isolate. Whole genome sequencing of this isolate revealed the presence of plasmids carrying additional resistance genes. This investigation showed the high prevalence of ESBL-producing E. coli in retail samples of minced meat. Also, the isolation of a strain of E. fergusonii is an additional concern, as some resistance genes are located in mobile elements, which can be transmitted to other bacteria. These evidences support the increasing public health concern considering the spreading of resistance genes through the food chain.

Characterization of a Carbapenem-Resistant BKC-1-Producing Clinical Isolate Belonging to the Pseudomonas putida Group from Brazil.

Since its first report, the class A Brazilian Klebsiella carbapenemase (BKC) has been detected only among Enterobacterales isolates from Brazilian hospitals. In this study, we characterized a multidrug-resistant Pseudomonas juntendi clinical isolate and identified a 43.3-kb plasmid carrying blaBKC-1 and a class 1 integron (In1996) containing the arr-2, qnrVC1, dfrA21, and aac(6')-Ib' gene cassettes. Our results confirm the ability of Pseudomonas putida group isolates to acquire antimicrobial resistance determinants and further act as resistance reservoirs.

Insights into the Bacterial Diversity and Detection of Opportunistic Pathogens in Mexican Chili Powder.

Chili powder is the most frequently consumed spice in Mexican diets. Thus, the dissemination of microorganisms associated with chili powder derived from Capsicum annuum L. is significant during microbial quality analysis, with special attention on detection of potential pathogens. The results presented here describe the initial characterization of bacterial community structure in commercial chili powder samples. Our results demonstrate that, within the domain Bacteria, the most abundant family was Bacillaceae, with a relative abundance of 99% in 71.4% of chili powder samples, while 28.6% of samples showed an average relative abundance of 60% for the Enterobacteriaceae family. Bacterial load for aerobic mesophilic bacteria (AMB) ranged from 104 to 106 cfu/g, while for sporulated mesophilic bacteria (SMB), the count ranged from 102 to 105 cfu/g. Bacillus cereus sensu lato (s.l.) was observed at ca. ˂600 cfu/g, while the count for Enterobacteriaceae ranged from 103 to 106 cfu/g, Escherichia coli and Salmonella were not detected. Fungal and yeast counts ranged from 102 to 105 cfu/g. Further analysis of the opportunistic pathogens isolated, such as B. cereus s.l. and Kosakonia cowanii, using antibiotic-resistance profiles and toxinogenic characteristics, revealed the presence of extended-spectrum ß-lactamases (ESBLs) and Metallo-ß-lactamases (MBLs) in these organisms. These results extend our knowledge of bacterial diversity and the presence of opportunistic pathogens associated with Mexican chili powder and highlight the potential health risks posed by its use through the spread of antibiotic-resistance and the production of various toxins. Our findings may be useful in developing procedures for microbial control during chili powder production.

ß-lactamasas de espectro extendido y factores de virulencia en Escherichia coli uropatógenas en asilos de ancianos en Lima, Perú / ß-lactamases and virulence factors in uropathogenic Escherichia coli in nursing homes in Lima, Peru

RESUMEN Los asilos de ancianos son instituciones con una alta prevalencia de infecciones del tracto urinario ocasionado por Escherichia coli productoras de ß-lactamasas de espectro extendido (BLEE), con diversos factores de virulencia. El objetivo del estudio fue determinar la frecuencia del gen bla CTX-M y de ocho genes de virulencia en 35 E. coli uropatógenas productoras de BLEE provenientes de seis asilos en Perú, durante el 2018. El 57,1% (20/35) de las E. coli fueron portadores del gen bla CTX-M. Además, se obtuvo una frecuencia del 46% (15/35) y 37% (13/35) de hly-alfa y cnf-1, respectivamente; elevada presencia de los genes iucC (63%, 22/35), aer (94%, 33/35) y chuA (94%, 33/34) y una frecuencia del 46% (16/35) y del 91% (32/34) de los genes pap GII y nanA, respectivamente. Existe predominancia en la distribución del gen bla CTX-M, además de una alta frecuencia de exotoxinas que le confieren una ventaja competitiva para diseminarse hacia el torrente sanguíneo.

ABSTRACT Nursing homes are institutions with high prevalence of urinary tract infections caused by ESBL-producing E. coli with several virulence factors. The aim of this study was to determine the frequency of the bla CTX-M gene and eight virulence genes in 35 ESBL-producing uropathogenic E. coli from six nursing homes in Peru during 2018. Of the E. coli samples, 57.1% (20/35) were carriers of the bla CTX-M gene. Furthermore, we obtained frequencies of 46% (15/35) and 37% (13/35) for hly-alpha and cnf-1, respectively; we also found high presence of the iucC (63%, 22/35), aer (94%, 33/35) and chuA genes (94%, 33/34) as well as a frequency of 46% (16/35) and 91% (32/34) for the pap GII and nanA genes, respectively. The bla CTX-M gene is predominant and a high frequency of exotoxins gives it a competitive advantage for spreading into the bloodstream.

High Prevalence of blaCTX-M in Fecal Commensal Escherichia coli from Healthy Children.

BACKGROUND: Antibiotic-resistant Escherichia coli can colonize the intestinal tract of healthy children, causing concern when antibiotic resistance is related to the presence of transferable mechanisms, such as extended-spectrum ß-lactamases (ESBLs). MATERIALS AND METHODS: Fecal samples from 41 healthy children from two villages of rural Peru were cultured on ceftriaxone-disks. ESBL production was confirmed with double disk synergy. In all ESBL-produced isolates, antibiotic susceptibility to 12 antibacterial agents was established by disk diffusion, while clonal relationships were determined by repetitive extragenic palindromic-polymerase chain reaction (REP-PCR). Presence of ST131 was determined using PCR. RESULTS: Ceftriaxone-resistant microorganisms were recovered from 39 samples belonging to 22 out of 41 children (53.7%). Of these, 80 ceftriaxone-resistant and two ceftriaxone-intermediate E. coli from inside ceftriaxone-halos were confirmed as ESBL-producers. All isolates were multidrug-resistant. In 79/80 (98.8%) ceftriaxone-resistant isolates, the presence of blaCTX-M was detected alone (58 isolates, or together with other ß-lactamase (blaTEM, 17 isolates; blaOXA-1-like, 3 isolates; blaTEM + blaOXA-1-like, 1 isolate), while in one isolate no such ESBL was identified. The two ceftriaxone-intermediate isolates recovered from the same sample, carried a blaTEM and blaSHV respectively. Thirty-four different clones were identified, with 4 clones being recovered from different samples from the same child. Twelve clones were disseminated among different children, including 5 clones disseminated between both villages. Two clones, accounting for 3 isolates and both recovered from the same children, belonged to E. coli ST131. CONCLUSION: This study demonstrates high prevalence of ESBL-carriers among healthy children living in a rural area of Peru, stressing the need for continuous surveillance and search for public health control measures.

Occurrence of clinically relevant antimicrobial resistance genes, including mcr-3 and mcr-7.1, in soil and water from a recreation club.

We researched clinically relevant antimicrobial resistance genes (ARGs) and mobile genetic elements (MGEs) in environmental samples from a recreation club in Brazil. A total of 172 amplicons (105 from soil and 67 from water) of 26 ARGs (20 among the soil and water samples; four only in soil samples; two only in water samples) were detected. Nine MGEs were detected, including plasmids and class 1 integron. The absolute abundance of the mcr-3 gene ranged from 1.12 × 102 to 1.81 × 103 copies/mL-1 in water samples. The rapid spread of mcr-like genes in several sources has generated a huge concern to public health. Accordingly, understanding of antimicrobial resistance, carry out surveillance studies may contribute to tackle antimicrobial resistance. As the environmental samples were collected from a popular recreation club in Brazil, this study points out to the risk and exposure to clinically relevant ARGs, especially to mcr-3 and mcr-7.1 genes.

Risk Factors of Death in Bloodstream Infections Caused by AmpC ß-Lactamase-Producing Enterobacterales in Patients with Neoplasia.

PURPOSE: The infections caused by ESCPM Enterobacterales (Enterobacter spp., Serratia spp., Citrobacter spp., Providencia spp. and Morganella spp.) have limited therapeutic options. Patients with neoplastic diseases are particularly vulnerable to bloodstream infections (BSIs). OBJECTIVE: To analyze determinant factors of death in patients with neoplasia complicated with BSI caused by ESCPM Enterobacterales. PATIENTS AND METHODS: A cohort study of patients aged 18 years or older with neoplasia and BSI due to ESCPM group was conducted at the Cancer Hospital I of the National Cancer Institute, Brazil, from September 2012 to December 2017. The variables associated with death were analyzed using multivariate logistic regression. RESULTS: Of the 103 patients included in the cohort, 67.0% were male, the median age was 63 years and 67.0% had solid tumors. Of the 107 BSI episodes evaluated, 70.1% were hospital-acquired infections, 54.2% were secondary to extravascular focus of infection, gastrointestinal tract (19.6%), mainly. Enterobacter spp. (n: 49, 45.4%) was the most frequent agent isolated followed by Serratia spp. (n: 34, 31.5%), Morganella morganii (n: 16, 14.9%), Citrobacter freundii. (n: 7, 6.5%) and Providencia spp. (n: 2, 1.8%). Ten (9.3%) BSI episodes were caused by multidrug-resistant ESCPM Enterobacterales (MDR-ESCPM). The 7-day and 30-day mortality were 9.3% and 21.5%, respectively. The BSIs caused by MDR-ESCPM were independently associated with 7-day death (OR = 21.62 95% CI: 1.81-258.51 P = 0.01). Monotherapy with piperacillin-tazobactam tended to be associated with 7-day death (OR = 10.46 95% CI: 0.97-112.91 P = 0.05) and 30-day death (OR = 2.73 95% CI: 0.96-7.70 P = 0.05). CONCLUSION: BSIs due to ESCPM group have high mortality and when caused by MDR-ESCPM are independently associated with 7-day death. The possible association of piperacillin-tazobactam monotherapy for BSI-ESCPM with death needs to be better studied.

Antimicrobial Resistance Patterns and Dynamics of Extended-Spectrum ß-Lactamase-Producing Uropathogenic Escherichia coli in Cusco, Peru.

Urinary tract infections (UTIs) are a common human infection. Antibiotic resistance in extended-spectrum ß-lactamase (ESBL)-producing uropathogenic E. coli (UPEC) is a major therapeutic challenge due to limited treatment alternatives. The aim was to characterize the antimicrobial resistance (AMR) and dynamics of ESBL-producing UPEC isolates from UTI cases seen at a local hospital in Cusco, Peru. Ninety-nine isolates from respective patients were characterized against 18 different antibiotics. Latent class analysis (LCA) was used to evaluate the dynamics across the study time according to resistance patterns. The median age of patients was 51 years old, and nearly half were women. ESBL-producing UPEC isolates were slightly more frequent in outpatient services than emergency rooms, and there were higher resistance rates in males compared to females. Half of the ESBL producers were resistant to aminoglycosides and nitrofurantoin. Cefoxitin and fosfomycin resistance was 29.3% and 14.1%, respectively. Resistance to carbapenems was not observed. All isolates were multidrug-resistant bacteria, and 16.2% (16/99) were also classified as extensively drug-resistant bacteria. The resistance patterns varied across the study time and differed regarding sex and healthcare service. The study revealed high levels of AMR to commonly used antimicrobials and a dynamic circulation of ESBL-producing UPEC isolates with varying resistance patterns.

ESBL-producing Escherichia coli and Klebsiella pneumoniae from health-care institutions in Mexico.

We investigated the phenotypic and molecular characteristics of Extended-Spectrum-ß-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae clinical isolates from four health-care institutions in Hermosillo, Sonora, Mexico. ESBL-producing isolates were collected from February to August 2016. The prevalence of ESBL-producing E. coli and K. pneumoniae was 11.9 and 8.7%, respectively. High dissemination of resistance to ciprofloxacin (88%), trimethoprim/sulfamethoxazole (72%) and aminoglycosides (59%) were detected, as well as susceptibility to meropenem, amikacin and tigecycline. The ESBL found variants were CTX-M-1 (88%) and CTX-M-9 (5%). The plasmid-mediated quinolone resistance (PMQR) gene aac(6´)-Ib-cr was identified in 62% of a representative sample, whereas the qnrB and qnrS genes were detected in 49% of the isolates. PFGE analyses detected many unrelated clones among the hospital or community isolates. A constant programme of epidemiological surveillance is recommended to understand the dynamics of bacterial resistance to both cephalosporin as well as the fluoroquinolone family of antibiotics.

Hygienic-sanitary quality and antimicrobial sensitivity profile of Escherichia coli in milk and cheese sold illegally in municipalities of northern Mato Grosso, Brazil

Products such as milk and cheese produced by hand and sold by small producers in open markets and at home are a reality in Brazil, despite legal prohibitions. In many cases, this leads to the production of food without hygienic conditions, which may constitute an important source of transmission of foodborne diseases and a danger to public health. This study proposes to examine the hygienic-sanitary quality of milk and cheese sold illegally in municipalities of northern Mato Grosso, Brazil, to undertake a phenotypical investigation of the presence of resistance of isolated colonies to antimicrobials and to detect the production of ß-lactamase enzymes: extended-spectrum ß-lactamase (ESBL), AmpC ß-lactamases (AmpC) and carbapenemases. The 25 milk and 37 cheese samples analyzed were subjected to the most probable number (MPN) test, isolation on eosin-methylene blue agar (EMB) agar and Escherichia coli identification by biochemical tests and disk diffusion test. Results showed that 76% of the milk samples and 67.57% of the cheese samples had thermotolerant coliform counts above the value allowed by the legislation. The milk and cheese isolates showed 15.79 and 5.88% resistance, respectively, to at least one of the tested antimicrobials. No ß-lactamase enzyme production was observed in the isolates.

Colistin Heteroresistance among Extended Spectrum ß-lactamases-Producing Klebsiella pneumoniae.

Colistin-heteroresistant (CST-HR) Enterobacterales isolates have been identified recently, challenging the clinical laboratories since routine susceptibility tests fail to detect this phenotype. In this work we describe the first CST-HR phenotype in extended-spectrum ß-lactamase (ESBL)-producing Klebsiella pneumoniae isolates in South America. Additionally, we determine the genomic mechanisms of colistin heteroresistance in these strains. The CST-HR phenotype was analyzed by the population analysis profile (PAP) method, and mutations associated with this phenotype were determined by whole-genome sequencing (WGS) and the local BLAST+ DB tool. As a result, 8/60 isolates were classified as CST-HR according to the PAP method. From WGS, we determined that the CST-HR isolates belong to three different Sequence Types (STs) and four K-loci: ST11 (KL15 and KL81), ST25 (KL2), and ST1161 (KL19). We identified diverse mutations in the two-component regulatory systems PmrAB and PhoPQ, as well as a disruption of the mgrB global regulator mediated by IS1-like and IS-5-like elements, which could confer resistance to CST in CST-HR and ESBL-producing isolates. These are the first descriptions in Chile of CST-HR in ESBL-producing K. pneumoniae isolates. The emergence of these isolates could have a major impact on the effectiveness of colistin as a "last resort" against these isolates, thus jeopardizing current antibiotic alternatives; therefore, it is important to consider the epidemiology of the CST-HR phenotype.

High frequency of gram-negative bacilli harboring blaKPC-2 in the different stages of wastewater treatment plant: A successful mechanism of resistance to carbapenems outside the hospital settings.

Wastewater treatment plants (WWTPs) are considered to be a reservoir and a source of bacterial resistance. Worryingly, the presence of carbapenem-resistant Gram-negative bacilli (CRGNB) in WWTPs has recently been reported, but there are still many research gaps regarding its emergence and impact. The distribution of CRGNB in the different stages of a WWTP in Colombia and the relationship between the physicochemical factors involved with their presence are described in this paper. Additionally, given the impact on public health, the CRGNB detected were compared with isolates previously found in hospital patients. Residual water samples were taken from five different stages of a WWTP between January and July 2017. A total of 390 GNB were isolated, and a significant frequency of CRGNB harboring blaKPC-2 (38.2%, n = 149/390) was detected, of which 57% were Enterobacteriaceae, 41.6% Aeromonadaceae, and 1.3% Pseudomonadaceae. The Enterobacteriaceae were more frequent in the raw effluent compared to the Aeromonadaceae, which in turn were more prevalent in the recycled activated sludge and final effluent. Environmental variables such as pH, oxygen, chemical oxygen demand, and temperature were significantly correlated with the quantification of carbapenem-resistant Enterobacteriaceae (CRE) at specific points in the WWTP. Interestingly, isolated K. pneumoniae harboring blaKPC-2 from the WWTPs were diverse and did not relate genetically to the hospital strains with which they were compared. In conclusion, these results confirm the worrying scenario of the dissemination and persistence of emerging contaminants such as CRGNB harboring blaKPC-2, and reinforce the need to establish strategies aimed at containing this problem using multifocal interventions.