Increase in Incidence Rates and Risk Factors for Multidrug Resistant Bacteria in Septic Children: A Nationwide Spanish Cohort Study (2013-2019)

The emergence of multidrug-resistant (MDR) bacteria in children is a growing concern, particularly among septic patients, given the need for first-right dosing. Our aim was to determine the incidence rates and factors associated with MDR-sepsis in the pediatric intensive care unit (PICU), using data from the Spanish ENVIN-HELICS PICU registry between 2013 and 2019. The rate of MDR bacteria among septic children ranged between 5.8 and 16.2% throughout this study period, with a significant increase since 2015 (p = 0.013). MDR-gram-negative bacteria (92%), particularly EBL-Enterobacterales (63.7%), were the most frequent causative microorganisms of MDR-sepsis. During this study period, sixteen MDR-sepsis (32.6%) corresponded to intrahospital infections, and 33 (67.4%) had community-onset sepsis, accounting for 10.5% of the overall community-onset sepsis. Independent risk factors associated with MDR-sepsis were antibiotics 48 h prior to PICU admission (OR 2.38) and PICU onset of sepsis (OR 2.58) in >1 year-old children, and previous malnourishment (OR 4.99) in <1 year-old children. Conclusions: There was an alarming increase in MDR among septic children in Spain, mainly by gram-negative (ESBL-Enterobacterales), mostly coming from the community setting. Malnourished infants and children on antibiotics 48 h prior to PICU are at increased risk and therefore require closer surveillance.

In Vitro Activity of Omadacycline and Comparator Antibiotics against Extended-Spectrum Beta-Lactamase-Producing Escherichia coli and Klebsiella pneumoniae Urinary Isolates

Limited oral antibiotic options exist for urinary tract infections (UTI) caused by ESBL-producing Enterobacterales. The aim of the study was to evaluate in vitro activity of omadacycline and comparator antibiotics against clinical ESBL-producing and non-ESBL-producing E. coli and K. pneumoniae urinary isolates. 102 isolates each of E. coli and K. pneumoniae were collected from clinical urine specimens in 2019. By design, an equal number of each species were included that tested positive and negative for ESBL production. Omadacycline MICs were determined using gradient test strips and compared to MICs of comparator antibiotics as determined by an automated broth microdilution system. Isolates were considered susceptible to omadacycline if the MIC was ≤4 µg/mL for each species. 54.9% of all ESBL-producing isolates were susceptible to omadacycline, but better susceptibility was observed for ESBL-producing E. coli (74.5%). Omadacycline MICs were 2-4 fold lower for E. coli and K. pneumoniae strains not producing ESBL. The omadacycline MIC 50 and 90 values were 4 and 16 µg/mL, respectively, for all isolates studied. 74.5% of all isolates were considered susceptible to omadacycline. MICs were generally lower for E. coli strains with MIC 50 and 90 values of 4 and 8 µg/mL, respectively (87.3% susceptible), compared with K. pneumoniae. Overall, the most active agents were omadacycline and nitrofurantoin, while other comparator antibiotics were less active. Omadacycline represents a promising oral antibiotic for treating UTI caused by ESBL-producing E. coli, particularly when resistance limits other oral options. Prospective, controlled clinical trials are needed to validate these in vitro results.

Co-Harboring of Beta-Lactamases and mcr-1 Genes in Escherichia coli and Klebsiella pneumoniae from Healthy Carriers and Backyard Animals in Rural Communities in Ecuador

Few studies have addressed drug resistance of Enterobacterales in rural communities in developing countries. This study aimed to determine the coexistence of extended-spectrum β-lactamase (ESBL) and carbapenemase genes in Escherichia coli and Klebsiella pneumoniae strains carrying the mcr-1 gene in rural communities in Ecuador from healthy humans and their backyard animals. Sixty-two strains, thirty E. coli and thirty-two K. pneumoniae strains carrying the mcr-1 gene were selected from a previous study. PCR were performed for the presence of ESBLs and carbapenemase genes. The strains were further characterized, and the genetic relationship was studied with multi-locus sequencing typing (MLST) of seven housekeeping genes. Fifty-nine of the sixty-two mcr-1 isolates (95%) harbored at least on β-lactam resistance gene. The most prevalent ESBL genes were the bla_TEM genes (present in in 80% of the E. coli strains) and the bla_SHV gene (present in 84% of the K. pneumoniae strains). MSLT analysis revealed 28 different sequence types (ST); 15 for E. coli and 12 for K. pneumoniae, with most ST never described in humans and animals. The coexistence of mcr-1 and β-lactams resistant genes in E. coli and K. pneumoniae strains is alarming and threatens the efficacy of last-resort antibiotics. Our findings highlight backyard animals as a reservoir of mcr-1/β-lactams resistant genes.

What Is in the Salad? Escherichia coli and Antibiotic Resistance in Lettuce Irrigated with Various Water Sources in Ghana

INTRODUCTION

Safety of the environment in which vegetables are grown, marketed and consumed is paramount as most are eaten raw. Irrigation sources include open drains and streams, which are often contaminated with human and animal waste due to poor sanitation infrastructure. In irrigated vegetable farms using such sources in Ghana, we assessed Escherichia coli counts, antibiotic resistance patterns and resistant genes on irrigated lettuce.

METHODS

A cross-sectional study was conducted between January-May 2022, involving five major vegetable farms in Ghana.

RESULTS

Escherichia coli was found in all 25 composite lettuce samples analyzed. Counts expressed in CFU/g ranged from 186 to 3000, with the highest counts found in lettuce irrigated from open drains (1670) and tap water using hose pipes (3000). Among all bacterial isolates, resistance ranged between 49% and 70% for the Watch group of antibiotics, 59% for the Reserved group and 82% were multidrug-resistant. Of 125 isolates, 60 (48%) were extended-spectrum beta-lactamase-producing, of which five (8%) had the blaTEM-resistant gene.

CONCLUSIONS

Lettuce was contaminated with Escherichia coli with high levels of antibiotic resistance. We call on the Ghana Ministry of Food and Agriculture, Food and Drugs Authority and other stakeholders to support farmers to implement measures for improving vegetable safety.

Prevalence, Risk Factors, and Genetic Characterization of Extended-Spectrum Beta-Lactamase Escherichia coli Isolated From Healthy Pregnant Women in Madagascar

Antimicrobial resistance is a major public health concern worldwide affecting humans, animals and the environment. However, data is lacking especially in developing countries. Thus, the World Health Organization developed a One-Health surveillance project called Tricycle focusing on the prevalence of ESBL-producing Escherichia coli in humans, animals, and the environment. Here we present the first results of the human community component of Tricycle in Madagascar. From July 2018 to April 2019, rectal swabs from 492 pregnant women from Antananarivo, Mahajanga, Ambatondrazaka, and Toamasina were tested for ESBL-E. coli carriage. Demographic, sociological and environmental risk factors were investigated, and E. coli isolates were characterized (antibiotic susceptibility, resistance and virulence genes, plasmids, and genomic diversity). ESBL-E. coli prevalence carriage in pregnant women was 34% varying from 12% (Toamasina) to 65% (Ambatondrazaka). The main risk factor associated with ESBL-E. coli carriage was the rainy season (OR = 2.9, 95% CI 1.3-5.6, p = 0.009). Whole genome sequencing was performed on 168 isolates from 144 participants. bla CTX-M-15 was the most frequent ESBL gene (86%). One isolate was resistant to carbapenems and carried the bla NDM-5 gene. Most isolates belonged to commensalism associated phylogenetic groups A, B1, and C (90%) and marginally to extra-intestinal virulence associated phylogenetic groups B2, D and F (10%). Multi locus sequence typing showed 67 different sequence types gathered in 17 clonal complexes (STc), the most frequent being STc10/phylogroup A (35%), followed distantly by the emerging STc155/phylogroup B1 (7%), STc38/phylogroup D (4%) and STc131/phylogroup B2 (3%). While a wide diversity of clones has been observed, SNP analysis revealed several genetically close isolates (n = 34/168) which suggests human-to-human transmissions. IncY plasmids were found with an unusual prevalence (23%), all carrying a bla CTX-M-15. Most of them (85%) showed substantial homology (≥85%) suggesting a dissemination of IncY ESBL plasmids in Madagascar. This large-scale study reveals a high prevalence of ESBL-E. coli among pregnant women in four cities in Madagascar associated with warmth and rainfall. It shows the great diversity of E. coli disseminating throughout the country but also transmission of specific clones and spread of plasmids. This highlights the urgent need of public-health interventions to control antibiotic resistance in the country.

Identity of blaCTX-M Carrying Plasmids in Sequential ESBL-E. coli Isolates from Patients with Recurrent Urinary Tract Infections

Plasmid-mediated multidrug resistance in E. coli is becoming increasingly prevalent. Considering this global threat to human health, it is important to understand how plasmid-mediated resistance spreads. From a cohort of 123 patients with recurrent urinary tract infections (RUTI) due to extended spectrum beta-lactamase (ESBL)-producing Escherichia coli (ESBL E. coli), only five events with a change of ESBL E. coli strain between RUTI episodes were identified. Their bla_CTX-M encoding plasmids were compared within each pair of isolates using optical DNA mapping (ODM) and PCR-based replicon typing. Despite similar bla_CTX-M genes and replicon types, ODM detected only one case with identical plasmids in the sequential ESBL E. coli strains, indicating that plasmid transfer could have occurred. For comparison, plasmids from seven patients with the same ESBL E. coli strain reoccurring in both episodes were analyzed. These plasmids (encoding bla_CTX-M-3, bla_CTX-M-14, and bla_CTX-M-15) were unaltered for up to six months between recurrent infections. Thus, transmission of bla_CTX-M plasmids appears to be a rare event during the course of RUTI. Despite the limited number (n = 23) of plasmids investigated, similar bla_CTX-M-₁₅ plasmids in unrelated isolates from different patients were detected, suggesting that some successful plasmids could be associated with specific strains, or are more easily transmitted.

A Novel Lineage of Ceftriaxone-resistant Salmonella Typhi From India That Is Closely Related to XDR S. Typhi Found in Pakistan

Two MDR Salmonella Typhi isolates from India were found by whole genome sequencing to be closely related to the 2016 XDR S. Typhi outbreak strain from Pakistan. The Indian isolates have no chromosomal antimicrobial resistance cassette but carry the IncY plasmid p60006. Both isolates are susceptible to chloramphenicol, azithromycin, and carbapenems.

Broiler Farms and Carcasses Are an Important Reservoir of Multi-Drug Resistant Escherichia coli in Ecuador

Antimicrobial resistance (AMR) is a major health threat for public and animal health in the twenty-first century. In Ecuador, antibiotics have been used by the poultry industry for decades resulting in the presence of multi-drug resistant (MDR) bacteria in the poultry meat production chain, with the consequent risk for public health. This study evaluated the prevalence of ESBL/AmpC and mcr genes in third-generation cephalosporin-resistant Escherichia coli (3GC-R E. coli) isolated from broiler farms (animal component), broiler carcasses (food component), and human enteritis (human component) in Quito-Ecuador. Samples were collected weekly from November 2017 to November 2018. For the animal, food, and human components, 133, 335, and 302 samples were analyzed, respectively. Profiles of antimicrobial resistance were analyzed by an automated microdilution system. Resistance genes were studied by PCR and Sanger sequencing. From all samples, 122 (91.7%), 258 (77%), and 146 (48.3%) samples were positive for 3GC-R E. coli in the animal, food, and human components, respectively. Most of the isolates (472/526, 89.7%) presented MDR phenotypes. The ESBL bla_CTX-M-55, bla_CTX-M-3, bla_CTX-M-15, bla_CTX-M-65, bla_CTX-M-27, and bla_CTX-M-14 were the most prevalent ESBL genes while bla_CMY-2 was the only AmpC detected gene. The mcr-1 gene was found in 20 (16.4%), 26 (10.1%), and 3 (2.1%) of isolates from animal, food, and human components, respectively. The implication of poultry products in the prevalence of ESBL/AmpC and mcr genes in 3GC-R must be considered in the surveillance of antimicrobial resistance.

Third-generation cephalosporin resistant Enterobacteriaceae in neonates and young infants: impact and outcome

OBJECTIVE

Third-generation cephalosporins resistant Enterobacteriaceae (3GCR-EB) are a major threat in severely ill neonates hospitalized in Neonatal Intensive Care Units. Still, the particular impact of 3GCR-EB on outcomes in the wide neonatal population is not well-appreciated. We aimed to study the impact of 3GCR-EB on the length of hospital stay and mortality of a general population of neonates and young infants.

STUDY DESIGN

This was a retrospective cohort study of neonates and young infants born in eight Israeli hospitals between 2009 and 2013, with a culture taken within three months after birth that tested positive for Enterobacteriaceae (EB). Data for this study were taken from centralized electronic health records included inpatient, outpatient, socio-demographic, administrative and laboratory information. The main outcomes were length of stay and mortality. The main explanatory variable was an isolation of 3GCR-EB in any bacterial culture taken from a neonate or young infant.

RESULTS

Cultures were taken for 31,921 neonates and young infants; 2647 (8.3%) tested positive for EB and 290 (11%) tested positive for 3GCR-EB. Length of stay for those who tested positive was 2.8 times longer (95%CI: 2.70-2.91, p ˂ .001) than patients who tested positive for 3GC-susceptible EB. 3GCR-EB were also associated with increased mortality (OR: 12.06, 95%CI: 4.92-32.29).

CONCLUSIONS

Neonates with third-generation cephalosporins resistant Enterobacteriaceae had extended hospitalization and increased mortality, which was mostly significant in normal gestational weight newborns.

A One Health Comparative Assessment of Antimicrobial Resistance in Generic and Extended-Spectrum Cephalosporin-Resistant Escherichia coli from Beef Production, Sewage and Clinical Settings

This study aimed to compare antimicrobial resistance (AMR) in extended-spectrum cephalosporin-resistant and generic Escherichia coli from a One Health continuum of the beef production system in Alberta, Canada. A total of 705 extended-spectrum cephalosporin-resistant E. coli (ESC^r) were obtained from: cattle feces (CFeces, n = 382), catch basins (CBasins, n = 137), surrounding streams (SStreams, n = 59), beef processing plants (BProcessing, n = 4), municipal sewage (MSewage; n = 98) and human clinical specimens (CHumans, n = 25). Generic isolates (663) included: CFeces (n = 142), CBasins (n = 185), SStreams (n = 81), BProcessing (n = 159) and MSewage (n = 96). All isolates were screened for antimicrobial susceptibility to 9 antimicrobials and two clavulanic acid combinations. In ESC^r, oxytetracycline (87.7%), ampicillin (84.4%) and streptomycin (73.8%) resistance phenotypes were the most common, with source influencing AMR prevalence (p < 0.001). In generic E. coli, oxytetracycline (51.1%), streptomycin (22.6%), ampicillin (22.5%) and sulfisoxazole (14.3%) resistance were most common. Overall, 88.8% of ESC^r, and 26.7% of generic isolates exhibited multi-drug resistance (MDR). MDR in ESC^r was high from all sources: CFeces (97.1%), MSewage (96.9%), CHumans (96%), BProcessing (100%), CBasins (70.5%) and SStreams (61.4%). MDR in generic E. coli was lower with CFeces (45.1%), CBasins (34.6%), SStreams (23.5%), MSewage (13.6%) and BProcessing (10.7%). ESBL phenotypes were confirmed in 24.7% (n = 174) ESC^r and 0.6% of generic E. coli. Prevalence of bla genes in ESC^r were bla_CTXM (30.1%), bla_CTXM-1 (21.6%), bla_TEM (20%), bla_CTXM-9 (7.9%), bla_OXA (3.0%), bla_CTXM-2 (6.4%), bla_SHV (1.4%) and AmpC β-lactamase bla_CMY (81.3%). The lower AMR in ESC^r from SStreams and BProcessing and higher AMR in CHumans and CFeces likely reflects antimicrobial use in these environments. Although MDR levels were higher in ESC^r as compared to generic E. coli, AMR to the same antimicrobials ranked high in both ESC^r and generic E. coli sub-populations. This suggests that both sub-populations reflect similar AMR trends and are equally useful for AMR surveillance. Considering that MDR ESC^r MSewage isolates were obtained without enrichment, while those from CFeces were obtained with enrichment, MSewage may serve as a hot spot for MDR emergence and dissemination.

High Prevalence of CTX-M Type Extended-Spectrum Beta-Lactamase Genes and Detection of NDM-1 Carbapenemase Gene in Extraintestinal Pathogenic Escherichia coli in Cuba

Increase of extraintestinal pathogenic Escherichia coli (ExPEC) showing resistance to beta-lactams is a major public health concern. This study was conducted as a first molecular epidemiological study on ExPEC in Cuba, regarding prevalence of extended-spectrum beta-lactamases (ESBLs) and carbapenemase genes. A total of 306 ExPEC isolates collected in medical institutions in 16 regions in Cuba (2014–2018) were analyzed for their genotypes and presence of genes encoding ESBL, carbapenemase, plasmid-mediated quinolone resistance (PMQR) determinants by PCR and sequencing. The most common phylogenetic group of ExPEC was B2 (49%), followed by D (23%), A (21%), and B1 (7%). Among ESBL genes detected, bla_CTX-M was the most common and detected in 61% of ExPEC, with bla_CTX-M-15 being dominant and distributed to all the phylogenetic groups. NDM-1 type carbapenemase gene was identified in two isolates of phylogenetic group B1-ST448. Phylogenetic group B2 ExPEC belonged to mostly ST131 (or its single-locus variant) with O25b allele, harboring bla_CTX-M-27, and included an isolate of emerging type ST1193. aac (6’)-Ib-cr was the most prevalent PMQR gene (40.5%), being present in 54.5% of CTX-M-positive isolates. These results indicated high prevalence of CTX-M genes and the emergence of NDM-1 gene among recent ExPEC in Cuba, depicting an alarming situation.

Assessment of Antibiotic Levels, Multi-Drug Resistant Bacteria and Genetic Biomarkers in the Waters of the Rio Grande River Between the United States-Mexico Border

BACKGROUND

The worldwide emergence of multi-drug resistant bacteria has become a health crisis, as fewer or sometimes no antimicrobial agents are effective against these bacteria. The Rio Grande River is the natural boundary between the United States (US) and Mexico. It spans a border region between Texas, New Mexico and Mexico. Underserved populations on the Mexican side use the river for recreational purposes, while on the US side, the river is used for irrigation and as a source of drinking water.

OBJECTIVES

The purpose of the present study was to evaluate the concentration of antibiotic residues, to determine the presence of genetic elements conferring antibiotic resistance and to characterize multi-drug resistant bacteria in the waters of the Rio Grande River.

METHODS

Water samples were obtained from the Rio Grande River. Deoxyribonucleic acid (DNA) was extracted from both isolated bacteria and directly from the water. Amplification of selected genetic elements was accomplished by polymerase chain reaction. Identification and isolation of bacteria was performed through MicroScan autoSCAN-4. Fecal contamination was assessed by IDEXX Colilert. Antibiotic residues were determined by liquid chromatography and mass spectrometry.

RESULTS

Antibiotics were found in 92% of both water and sediment samples. Antibiotic concentrations ranged from 0.38 ng/L - 742.73 ng/L and 0.39 ng/l - 66.3 ng/g dry weight in water and sediment samples, respectively. Genetic elements conferring resistance were recovered from all collection sites. Of the isolated bacteria, 91 (64.08%) were resistant to at least two synergistic antibiotic combinations and 11 (14.79%) were found to be resistant to 20 or more individual antibiotics. Fecal contamination was higher during the months of April and July.

CONCLUSIONS

The 26 km segment of the Rio Grande River from Sunland Park NM to El Paso, TX and Juarez, Mexico is an area of concern due to poor water quality. The presence of multidrug resistant bacteria, antibiotics and mobile genetic elements may be a health hazard for the surrounding populations of this binational border region. Policies need to be developed for the appropriate management of the environmental natural resources in this border region.

COMPETING INTERESTS

The authors declare no competing financial interests.

Effective Oral Combination Treatment for Extended-Spectrum Beta-Lactamase-Producing Escherichia coli

Background: Extended-spectrum beta-lactamase-producing Escherichia coli (ESBL-EC) is increasing worldwide. The drugs of choice for treatment of ESBLs are parenteral carbapenems. The aim of this study was to evaluate the in vitro and in vivo efficacy of a new combination of oral cephalosporins and amoxicillin/clavulanate in treatment of ESBL-EC. Methods: A total of 150 ESBL-EC samples were collected over 1 year from two referral centers. Synergistic studies of cephalosporins and amoxicillin/clavulanate were performed in vitro using disk approximation and disk replacement methods. Combination treatment was assessed in vivo on 20 ESBL-EC urinary tract infection (UTI) patients. Results: ESBL-EC isolates were confirmed in 150 patients with a mean age of 46.67 years, 75.2% of them being women. Antibiotic susceptibility testing of isolates indicated high resistance rate to oral antibiotics. The frequency of positive synergy and mean distance of synergy between cephalosporins and amoxicillin/clavulanate was significantly higher with cefotaxime and cefixime compared with cefpodoxime, cefdinir, and ceftazidime using disk approximation and disk replacement methods (p < 0.05). Addition of amoxicillin/clavulanate enhanced the susceptibility rate with cefixime from 8.6% to 86.3%, significantly higher than with other cephalosporins (p < 0.0005). Cefixime and amoxicillin/clavulanate synergy was not affected by age, gender, hospital, department, sample type, or bacterial load. Eighteen of 20 ESBL-EC-positive UTI patients had a positive in vitro synergy test and complete clinical and microbiological resolution after completion of cefixime and amoxicillin/clavulanate oral treatment course. Conclusions: Cefixime and amoxicillin/clavulanate combination therapy could be an effective oral outpatient treatment option for ESBL-EC. In vitro synergistic testing is simple and predictive of successful treatment.

Antibiotic Susceptibilities and Genetic Characteristics of Extended-Spectrum Beta-Lactamase-Producing Escherichia coli Isolates from Stools of Pediatric Diarrhea Patients in Surabaya, Indonesia

The purpose of this study was to investigate extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli isolates from pediatric (aged 0 to 3 years) diarrhea patients in Surabaya, Indonesia, where this kind of survey is rare; our study included assessment of their antibiotic susceptibilities, as well as ESBL typing, multilocus sequence typing (MLST), and diarrheagenic E. coli (DEC)-typing. ESBL-producing E. coli were detected in 18.8% of all the samples. Many ESBL-producing E. coli had significantly lower susceptibility to gentamicin (p ＜ 0.0001) and the quinolones nalidixic acid (p＝0.004) and ciprofloxacin (p ＜ 0.0001) than non-producers. In ESBL-producing E. coli, 84.0% of strains expressed CTX-M-15 alone or in combination with other ESBL types. MLST revealed that 24.0% of ESBL-producers had sequence type 617, all of which expressed the CTX-M-15 gene; we also detected expression of 3 DEC-related genes: 2 enteroaggregative E. coli genes and 1 enteropathogenic E. coli gene. In conclusion, CTX-M-15-type ESBL-producing E. coli ST617 appear to have spread to Indonesia.

Fecal carriage of CTX-M β-lactamase-producing Enterobacteriaceae in nursing homes in the Kinki region of Japan

The detection rate of CTX-M-type β-lactamase-producing Enterobacteriaceae in Japan has significantly increased. Nursing homes may be a reservoir of antibiotic-resistant bacteria. Therefore, we determined the prevalence of, and risk factors associated with, fecal carriage of CTX-M-type β-lactamase-producing Enterobacteriaceae among nursing home residents. A total of 225 stool samples were collected for phenotypic and genotypic identification of extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae. Multivariate analysis was performed to identify the risk factors associated with fecal carriage of CTX-M producers. The prevalence of CTX-M-type ESBL-producing Enterobacteriaceae, as confirmed by phenotypic and genotypic methods, was 19.6% (44 of 225 samples). Escherichia coli was the predominant CTX-M-type ESBL-producing bacterium among these isolates (41 of 44 isolates). Genotyping of bla_CTX-M gene-positive isolates showed that 30 (68.2%), 13 (29.5%), and 1 (2.3%) of 44 samples belonged to groups CTX-M-9, CTX-M-1 and CTX-M-2, respectively. Among the CTX-M-type ESBL-producing Enterobacteriaceae found in nursing homes, 95.5% (42 of 44 isolates) were co-resistant to quinolone antibiotics. In multivariate logistic regression analysis, inability to turn over in bed, diabetes, and invasive procedures within the last 2 years were the only variables independently associated with fecal carriage of CTX-M-type ESBL producers. Nursing home residents in Japan exhibit a high prevalence of CTX-M-type ESBL-producing Enterobacteriaceae carriage, with a high level of co-resistance to quinolones.