OXA-48 Carbapenemase in Klebsiella pneumoniae Sequence Type 307 in Ecuador

Whole-genome sequencing of Klebsiella pneumoniae MDR circulating in a pediatric hospital setting: a comprehensive genome analysis of isolates from Guayaquil, Ecuador

BACKGROUND

Klebsiella pneumoniae is the major cause of nosocomial infections worldwide and is related to a worsening increase in Multidrug-Resistant Bacteria (MDR) and virulence genes that seriously affect immunosuppressed patients, long-stay intensive care patients, elderly individuals, and children. Whole-Genome Sequencing (WGS) has resulted in a useful strategy for characterizing the genomic components of clinically important bacteria, such as K. pneumoniae, enabling them to monitor genetic changes and understand transmission, highlighting the risk of dissemination of resistance and virulence associated genes in hospitals. In this study, we report on WGS 14 clinical isolates of K. pneumoniae from a pediatric hospital biobank of Guayaquil, Ecuador.

RESULTS

The main findings revealed pronounced genetic heterogeneity among the isolates. Multilocus sequencing type ST45 was the predominant lineage among non-KPC isolates, whereas ST629 was found more frequently among KPC isolates. Phylogenetic analysis suggested local transmission dynamics. Comparative genomic analysis revealed a core set of 3511 conserved genes and an open pangenome in neonatal isolates. The diversity of MLSTs and capsular types, and the high genetic diversity among these isolates indicate high intraspecific variability. In terms of virulence factors, we identified genes associated with adherence, biofilm formation, immune evasion, secretion systems, multidrug efflux pump transporters, and a notably high number of genes related to iron uptake. A large number of these genes were detected in the ST45 isolate, whereas iron uptake yersiniabactin genes were found exclusively in the non-KPC isolates. We observed high resistance to commonly used antibiotics and determined that these isolates exhibited multidrug resistance including β-lactams, aminoglycosides, fluoroquinolones, quinolones, trimetropins, fosfomycin and macrolides; additionally, resistance-associated point mutations and cross-resistance genes were identified in all the isolates. We also report the first K. pneumoniae KPC-3 gene producers in Ecuador.

CONCLUSIONS

Our WGS results for clinical isolates highlight the importance of MDR in neonatal K. pneumoniae infections and their genetic diversity. WGS will be an imperative strategy for the surveillance of K. pneumoniae in Ecuador, and will contribute to identifying effective treatment strategies for K. pneumoniae infections in critical units in patients at stratified risk.

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.

Molecular Genetic Epidemiology of an Emerging Antimicrobial-Resistant Klebsiella pneumoniae Clone (ST307) Obtained from Clinical Isolates in Central Panama

Klebsiella pneumoniae has been among the main pathogens contributing to the burden of antimicrobial resistance (AMR) in the last decade, and K. pneumoniae AMR strains predominantly cluster in the ST258 clonal complex. However, ST307 is emerging as an important high-risk clone. In Central America, there have been few studies on the molecular epidemiology of the K. pneumoniae strains involved in infections.

MATERIALS AND METHODS

We conducted an epidemiological study in three reference hospitals in the central region of Panama, using isolates of K. pneumoniae involved in infections, and identifying their AMR profile, associated clinical risk factors, and molecular typing using a multilocus sequence typing (ST) scheme.

RESULTS

Six STs were detected: 307 (55%), 152, 18, 29, 405, and 207. CTX-M-15- and TEM-type beta-lactamases were identified in 100% of ESBL-producing strains; substitutions in gyrA Ser83Ile and parC Ser80Ile were identified in all ST307s; and in ST152 gyrA Ser83Phe, Asp87Ala, and parC Ser80Ile, the qnrB gene was detected in all strains resistant to ciprofloxacin.

CONCLUSIONS

We present the first report on ST307 in three reference hospitals in the central region of Panama, which is a high-risk emerging clone and represents a public health alert for potential difficulties in managing K. pneumoniae infections in Panama, and which may extend to other Central American countries.

First detection and origin of multi-drug resistant Klebsiella pneumoniae ST15 harboring and OXA-48 in South America

OBJECTIVES

The emergence and spread of carbapenem resistant clones is of major concern for global health. This study aimed to characterize the first detected Klebsiella pneumoniae ST15 harboring the epidemic carbapenemase OXA-48 in South America.

METHODS

During a routine colonization screening with carbapenem-resistant bacteria, one K. pneumoniae strain (CGHM01) was isolated from the urine of an hospitalized patient suffering from a neurodegenerative disease in Uruguay. We used long-read whole-genome sequencing and a phylogenomic approach to characterize the emergence of K. pneumoniae CGHM01.

RESULTS

K. pneumoniae CGHM01 is a multi-drug resistant strain carrying an IncL/M plasmid that encodes the carbapenemase gene bla_OXA-48 within the Tn1999.2 transposon. Also, it carries an IncR plasmid harboring a class I integron with an array of antibiotic resistance genes including the extended-spectrum beta-lactamase bla_CTX-M-15. Two copies of bla_CTX-M-15 were also inserted in different positions of the chromosome. CGHM01 belongs to a ST15 sublineage that likely originated in continental Spain around 2012.

CONCLUSIONS

The asymptomatic carriage of this strain in the urinary tract warns about difficulties for detection and reporting of emerging carbapenem-resistant clones in new geographic areas where these are not endemic.