Microbiological profiles and antimicrobial resistance patterns of pediatric bloodstream pathogens in China, 2016-2018

Analysis of factors associated with mortality due to sepsis resulting from device-related infections

INTRODUCTION

Health care-associated infections (HAIs) contribute to morbidity and mortality and to the dissemination of multidrug-resistant organisms. Children admitted to the intensive care unit undergo invasive procedures that increase their risk of developing HAIs and sepsis. The aim of the study was to analyse factors associated with mortality due to sepsis arising from HAIs.

PATIENTS AND METHODS

We conducted a case-control study in a 7-bed multipurpose paediatric intensive care unit in a tertiary care teaching hospital. The sample consisted of 90 children admitted between January 2014 and December 2018. The case group consisted of patients who died from sepsis associated with the main health care-associated infections; the control group consisted of patients who survived sepsis associated with the same infections.

RESULTS

Death was associated with age less than or equal to 12 months, presence of comorbidity, congenital disease, recurrent ventilator-associated pneumonia and septic shock. In the multiple regression analysis, heart disease (OR, 12.48; CI 2.55-60.93; P = .002), infection by carbapenem-resistant bacteria (OR, 31.51; CI 4.01-247.25; P = .001), cancer (OR, 58.23; CI 4.54-746.27; P = .002), and treatment with adrenaline (OR, 13.14; CI 1.35-128.02; P = .003) continued to be significantly associated with death.

CONCLUSIONS

Hospital sepsis secondary to carbapenem-resistant bacteria contributed to a high mortality rate in this cohort. Children with heart disease or neoplasia or who needed vasopressor drugs had poorer outcomes.

Clinical characteristics and risk factors for neonatal bloodstream infection due to carbapenem-resistant Enterobacteriaceae: A single-centre Chinese retrospective study

OBJECTIVES

To analyse the clinical characteristics and risk factors for bloodstream infections (BSIs) caused by carbapenem-resistant Enterobacteriaceae (CRE) in neonates.

METHODS

This single-centre, retrospective study included all patients with BSIs admitted to a neonatal intensive care unit between 1 January 2015 and 30 April 2022. The clinical and microbiological data of patients were collected; predictors of 30-day mortality in patients with CRE BSIs were also identified in this study.

RESULTS

Among the 224 neonates with Enterobacteriaceae BSIs, 39.29% (88/224) of the patients developed CRE BSIs. The 30-day mortality rate reached up to 21.59% (19/88). The Quick Sequential Organ Failure Assessment score > 2 (odds ratio [OR] and 95% credibility interval [CI]: 3.852 [1.111-13.356], P < 0.05), prior to more than two kinds of antibiotics use (OR and 95% CI: 9.433 [1.562-56.973], P < 0.05), pneumonia (OR and 95% CI: 3.847 [1.133-13.061], P < 0.05), and caesarean section (OR and 95% CI: 2.678 [1.225-5.857], P < 0.05) were independent risk factors associated with CRE BSIs. Moreover, the risk factors for mortality in neonates with CRE BSIs were significantly associated with neonatal Sequential Organ Failure Assessment score > 6 (OR and 95% CI: 16.335 [1.446-184.517], P < 0.05).

CONCLUSION

Prior to more than two kinds of antibiotics use, Quick Sequential Organ Failure Assessment score > 2, pneumonia and caesarean section were independent risk factors for CRE BSIs. The Neonatal Sequential Organ Failure Assessment score > 6 was a risk factor for mortality associated with CRE BSIs.

Global mapping of antibiotic resistance rates among clinical isolates of Stenotrophomonas maltophilia: a systematic review and meta-analysis

INTRODUCTION

Infections caused by Stenotrophomonas maltophilia are clinically important due to its intrinsic resistance to a broad range of antibiotics. Therefore, selecting the most appropriate antibiotic to treat S. maltophilia infection is a major challenge.

AIM

The current meta-analysis aimed to investigate the global prevalence of antibiotic resistance among S. maltophilia isolates to the develop more effective therapeutic strategies.

METHOD

A systematic literature search was performed using the appropriate search syntax after searching Pubmed, Embase, Web of Science and Scopus databases (May 2023). Statistical analysis was performed using Pooled and the random effects model in R and the metafor package. A total of 11,438 articles were retrieved. After a thorough evaluation, 289 studies were finally eligible for inclusion in this systematic review and meta-analysis.

RESULT

Present analysis indicated that the highest incidences of resistance were associated with doripenem (97%), cefoxitin (96%), imipenem and cefuroxime (95%), ampicillin (94%), ceftriaxone (92%), aztreonam (91%) and meropenem (90%) which resistance to Carbapenems is intrinsic. The lowest resistance rates were documented for minocycline (3%), cefiderocol (4%). The global resistance rate to TMP-SMX remained constant in two periods before and after 2010 (14.4% vs. 14.6%). A significant increase in resistance to tigecycline and ceftolozane/tazobactam was observed before and after 2010.

CONCLUSIONS

Minocycline and cefiderocol can be considered the preferred treatment options due to low resistance rates, although regional differences in resistance rates to other antibiotics should be considered. The low global prevalence of resistance to TMP-SMX as a first-line treatment for S. maltophilia suggests that it remains an effective treatment option.

Current viewpoint on the epidemiology of nonfermenting Gram-negative bacterial strains

PURPOSE OF REVIEW

This article aims to review the epidemiology of nonfermenting Gram-negative bacilli (NFGNB) based on recent literature reports, particularly, of the less common, but with emerging clinical significance species.

RECENT FINDINGS

The reported frequency of multidrug-resistant Acinetobacter baumannii and Pseudomonas aeruginosa is increasing, with very significant variability, however, between different countries. Apart from the major NFGNB, that is, A. baumannii and P. aeruginosa, already recognized as of critical importance healthcare risks, several other NFGNB genera have been increasingly associated with diverse severe infections, such as Stenotrophomonas maltophilia, Burkholderia spp., Elizabethkingia spp., Chryseobacterium spp., Achromobacter spp., Alcaligenes spp., Sphingomonas spp., Shewanella spp. and Ralstonia spp., among others.

SUMMARY

The exploration of the epidemiology, as well as the pathogenic potential of the of the less frequent, but emerging and increasingly reported NFGNB, is crucial, not only for immunocompromised patients, but also for critically ill patients without overt immunosuppression. As we are heading fast towards a postantibiotic era, such information would contribute to the optimal antimicrobial management, that is, providing prompt, appropriate antimicrobial coverage when needed and, at the same time, avoiding overuse and/or inappropriate use of antimicrobial therapy. Also, it would help to better understand their transmission dynamics and to develop effective prevention strategies.

Bacterial Etiology and Antimicrobial Resistance Pattern of Pediatric Bloodstream Infections in Beijing, 2015-2019

Purpose

Bloodstream infections (BSIs) was an essential cause of morbidity and mortality in children. Empiric broad-spectrum treatment of BSIs may be costly and unable to effectively eliminate the correct pathogenic microbes, resulting in downstream antimicrobial resistance. The purpose was to provide evidence for diagnosis and treatment of bloodstream infections in pediatrics, by revealing the pathogen distribution and antibiotic resistance pattern of BSIs.

Methods

In this 5-year study, a total of 2544 pathogenic bacteria stains, isolated from 2368 patients with BSI, were retrospectively analyzed, to define the species distribution and the antimicrobial resistance pattern in Beijing.

Results

The most frequently isolated pathogenic bacteria were K. pneumoniae (12.1%), S. aureus (11.5%), E. coli (11.2%), and E. faecium (11.2%). Hematological malignancies were the most common disease among patients with underlying conditions. Methicillin resistance was detected in 30.0% of S. aureus and 81.7% of coagulase-negative Staphylococcus (CoNS), respectively. The detection rates of carbapenem-resistant-E. coli (CRECO) and carbapenem-resistant-K. pneumoniae (CRKPN) were 10.8% and 50.8%, respectively. In terms of 122 isolates of S. pneumonia, 5 isolates (4.1%) were penicillin-resistant Streptococcus pneumoniae (PRSP); meanwhile, 50 isolates (41.0%) were penicillin-intermediate Streptococcus pneumoniae (PISP). Among the non-fermentative gram-negative bacilli isolates, 22.8% and 26.9% of the P. aeruginosa, were resistant to imipenem and meropenem. Furthermore, the resistance rates of A. baumannii to imipenem and meropenem both were 54.5%.

Conclusion

In the study, we demonstrated the characteristics of bloodstream infections and antimicrobial susceptibility pattern of pediatrics in Beijing. Gram positive bacteria were the main pathogens of BSIs. CoNS strains presented even higher resistance to multiple antibiotics, including methicillin, than S. aureus. K. pneumoniae and E. coli represent the most common isolated gram-negative bacteria and exhibited high resistance to a variety of antimicrobial agents. Therefore, it was of critical importance to implement appropriate antimicrobial medication according to pathogen distribution and drug susceptibility test.

Prevalence of Multidrug-Resistant Pathogens Causing Neonatal Early and Late Onset Sepsis, a Retrospective Study from the Tertiary Referral Children's Hospital

Introduction

Sepsis is the most severe infectious disease with the highest mortality rate, particularly among neonates admitted to the neonatal intensive care unit (NICU). This study retrospectively analyzed the epidemiology, antibiotic resistance profiles, and prevalence of multidrug-resistant (MDR) bacteria isolated from blood or cerebrospinal fluid (CSF) cultures in order to evaluate the appropriateness of initial empirical therapy for neonatal sepsis.

Methods

A retrospective study was conducted in the NICU from January 1, 2015, to December 31, 2022. Microbiological data from patients admitted to the NICU were anonymously extracted from the Laboratory of Microbiology database. Neonatal sepsis was classified into two types: early-onset sepsis (EOS), which occurs within the first 72 hours of life, and late-onset sepsis (LOS) for those begins later.

Results

A total of 679 bacterial strains, 543 from blood and 136 from CSF, were detected in 631 neonates. Among these, 378 isolates (55.67%) were Gram-positive bacteria, and 301 isolates (44.33%) were Gram-negative bacteria. The most frequently isolated pathogens were Coagulase-negative staphylococci (CoNS) (36.52%), followed by Klebsiella pneumoniae (20.47%) and Escherichia coli (13.84%). In EOS, 121 strains were found, CoNS represented the majority (33.88%), followed by Klebsiella pneumoniae (23.97%) and Escherichia coli (8.26%). Early-onset septicemia exhibited 67 (55.37%) MDR bacteria. In LOS, 558 strains were isolated, CoNS represented the majority of pathogens (37.10%), followed by Klebsiella pneumoniae (19.71%) and Escherichia coli (15.05%). Late-onset septicemia showed 332 (59.50%) MDR bacteria. High rates of MDR were found in CoNS (76.21%), carbapenem-resistant Klebsiella pneumoniae (66.91%), and MRSA (33.33%).

Conclusion

The study revealed an alarming prevalence of MDR strains isolated from neonatal sepsis, emphasizing the necessity of finding effective prevention and treatment measures. Colistin can be used for MDR Gram-negative bacteria, while vancomycin and teicoplanin can be considered treatment therapies for staphylococcal infections.

Inappropriate empirical antibiotic therapy was an independent risk factor of pediatric persistent S. aureus bloodstream infection

Persistent S. aureus bloodstream infection (PSBSI) increased the incidence of metastatic infection and mortality. We aimed to clarify its risk factors and correlation with metastatic infection and septic shock in children. This retrospective and observational study enrolled children with S. aureus bloodstream infection who admitted to Children's Hospital of Chongqing Medical University between January 2016 and December 2021. The logistic regression model was used for multivariable analyses to determine independent factors associated with PSBSI and clarify the effect of persistent S. aureus bloodstream infection and other factors on metastatic infection and septic shock. One hundred and twenty-seven children were included in this study retrospectively. There were thirty-two cases in the persistent S. aureus bloodstream infection group and ninety-five children in the non-persistent infection group. Multivariate logistic regression analysis indicated that inappropriate empirical antibiotic therapy (OR, 7.26; 95%CI, 2.48-21.30; P<0.01) was an independent risk factor of persistent S. aureus bloodstream infection. Persistent S. aureus bloodstream infection (OR, 6.40; 95%CI, 2.08-19.70; P<0.01) and community-acquired S. aureus bloodstream infection (OR, 4.75; 95%CI, 1.34-16.89; P=0.02) were independent predictors of metastatic infection. Pittsburgh bacteremia scores ≥ 2 (OR, 28.81; 95%CI, 5.26-157.99; P<0.01), hypoalbuminemia (OR, 13.34; 95%CI, 2.43-73.28; P<0.01) and persistent S. aureus bloodstream infection (OR, 5.48; 95%CI, 1.13-26.54; P=0.04) were independent risk factors of septic shock.

CONCLUSION

Inappropriate empirical antibiotic therapy was an independent risk factor of pediatric persistent S. aureus bloodstream infection. Pediatric persistent S. aureus bloodstream infection was associated with metastatic infection and septic shock.

WHAT IS KNOWN

• Pathogenic features such as Methicillin-resistant S. aureus and sources of infection such as central venous catheter related infection were risk factors of PSBSI in adults. • PSBSI increased the incidence of metastatic infection and mortality in adults.

WHAT IS NEW

• Inappropriate empirical antibiotic therapy was an independent risk factor of pediatric persistent S. aureus bloodstream infection. • Pediatric persistent S. aureus bloodstream infection was associated with metastatic infection and septic shock.

Prevalence, serotype, and antimicrobial resistance profiles of children infected with Salmonella in Guangzhou, southern China, 2016-2021

Purpose

Salmonella infection is a key global public health concern and has lead to an increased economic burden on society. We investigated the epidemiological characteristics and antimicrobial resistance profiles of clinically isolated Salmonella strains in Guangzhou Women and Children's Medical Center.

Patients and methods

This was a retrospective study of 1,338 Salmonella strains collected from children in Guangzhou Women and Children's Medical Center during 2016 to 2021.

Results

The results revealed that 1,338 cases of Salmonella were mainly isolated from feces and blood samples. The age distribution was dominated by infants under 3 years old. The seasonal distribution was high in summer and autumn. 48 serotypes were detected, and S. typhimurium (78.7%) was the predominant serogroup. The results of antimicrobial susceptibility showed that the highest resistance was observed in ampicillin (84.5%), while lower resistance was observed in piperacillin/tazobactam, cefoperazone/sulbactam and ciprofloxacin. The antimicrobial resistance rate of fecal isolates was higher than that of blood isolates. The five-year average detection rate of multi-drug resistant Salmonella was 8.5% (114/1338) and the MDR rate of S. typhimurium was the lowest (6.9%; 73/1053).

Conclusion

We concluded that antibacterial treatment should be carefully selected according to serotype and antimicrobial sensitivity results in children. Antimicrobial resistance monitoring for multi-drug resistant Salmonella is still required.

Invasive Salmonella Infections Among Children in Shenzhen, China: A Five-year Retrospective Review

BACKGROUND

Invasive Salmonella infections are highly prevalent worldwide. Clinical data of childhood invasive Salmonella infections from China are limited.

METHODS

Data of hospitalized children <18 years old with invasive Salmonella infections from 2016 to 2020 in Shenzhen Children's Hospital in Shenzhen were retrospectively collected. Serotypes and antimicrobial susceptibility tests of the invasive Salmonella isolates were performed.

RESULTS

Sixty-three cases were enrolled during the 5-year study period including 8 in 2016, 11 in 2017, 16 in 2018, 6 in 2019 and 22 in 2020. The median age was 15 months (interquartile range, 11-22 months), and 79.4% (50 cases) were <2 years of age. Underlying diseases were found in 28.6% (18 cases) of the patients with a great variety, but no cases of malaria or HIV infection were identified. Most of the invasive Salmonella cases were bloodstream infections (84.1%), followed by osteoarthritis (11.1%) and meningitis (4.8%). Gastroenteritis (49.2%) and pneumonia (28.6%) were found to be the major manifestations among the patients. Furthermore, invasive Salmonella infections resulted in the death of 3 children (4.8%). Salmonella enteritis (12 cases; 15.9%) and Salmonella typhimurium (9 cases; 19.0%) as the most common serovars were identified. The resistance rates of Salmonella strains to ceftriaxone, ceftazidime and cefepime were also measured to be 17.5%, 17.5% and 9.5%, respectively.

CONCLUSIONS

An increasing number of childhood invasive Salmonella infections with a broad range of serotypes was observed in Shenzhen, China. It is critical to pay attention to the antimicrobial resistance of the isolates taken from children with invasive Salmonella infections.

Large-Scale Studies on Antimicrobial Resistance and Molecular Characterization of Escherichia coli from Food Animals in Developed Areas of Eastern China

Widely distributed multidrug-resistant (MDR) bacteria threaten animals and human health. Nevertheless, few antimicrobial resistance (AMR) surveys of large-scale animal-derived bacteria have been explored. Here, 1,468 (97.54%) Escherichia coli strains were isolated from 1,505 pig (1,060) and chicken (445) anal swab samples from 11 cities in Zhejiang Province, China, in 2020. These isolates had a high resistance to tetracycline (92.92%), sulfisoxazole (93.05%), florfenicol (83.11%), and ampicillin (78.27%). More than 88.68% of the strains were MDR bacteria. A low AMR ratio to the "last-resort" antimicrobials tigecycline (0.75%), colistin (1.36%), and meropenem (0.75%) were found. The AMR of E. coli from pigs was higher than that of chickens. Eighteen strains among 31 MDR strains that were resistant to "last-resort" antimicrobials could transfer the AMR genes (mcr-1, tet(X), and blaNDM) to the recipient strain J53, which confer colistin, tigecycline, and carbapenem resistance, respectively. The homology among mcr-1-carrying isolates was relatively high, and the sequence types were mainly ST5529, ST101, and ST354, while the homology of isolates harboring tet(X4) and blaNDM-5 genes were different. The mcr-1, blaNDM-5, and tet(X4) genes in strains LS45, JH51, and TZ118 were identified on the Incl2, IncHI2, and IncX1 plasmids, respectively. Moreover, tet(A), sul2, floR, and blaTEM-1B were the most common ARGs in 31 strains. Additionally, the heavy metals copper and zinc had a significant correlation with amoxicillin/clavulanate and tetracycline resistance. Controlling the movement of animals between cities and reducing the use of antimicrobials are effective methods to reduce the threat of AMR bacteria. IMPORTANCE Pigs and chickens are the most common food animals that are the important vectors for spreading antimicrobial-resistant pathogens among animals and humans. Limited systematic AMR monitoring of these food animal origin bacteria had been reported, especially in developed areas of China. Our study provides a comprehensive and systematic study of AMR in Escherichia coli from eastern China. The AMR of E. coli strains among the animals or cities has statistically significant differences. Moreover, the mcr-1, tet(X4), and blaNDM-5 genes, considered resistant to the last line of AMR, were identified in part of farms. The transferability and the prevalence of these AMR strains were intensively studied. Our monitoring is comparable to human clinical research and has an essential reference for public health safety. These findings will provide early warning for AMR strains and guide the clinical use of antibiotics to control the spread of antibiotic resistance.

Clinical profiles and antimicrobial resistance patterns of invasive Salmonella infections in children in China

Invasive Salmonella infections result in a significant burden of disease including morbidity, mortality, and financial cost in many countries. Besides typhoid fever, the clinical impact of non-typhoid Salmonella infections is increasingly recognized with the improvement of laboratory detection capacity and techniques. A retrospective multicenter study was conducted to analyze the clinical profiles and antimicrobial resistance patterns of invasive Salmonella infections in hospitalized children in China during 2016–2018. A total of 130 children with invasive Salmonella infections were included with the median age of 12 months (range: 1–144 months). Seventy-nine percent of cases occurred between May and October. Pneumonia was the most common comorbidity in 33 (25.4%) patients. Meningitis and septic arthritis caused by nontyphoidal Salmonella (NTS) infections occurred in 12 (9.2%) patients and 5 (3.8%) patients. Patients < 12 months (OR: 16.04) and with septic shock (OR: 23.4), vomit (OR: 13.33), convulsion (OR: 15.86), C-reactive protein (CRP) ≥ 40 g/L (OR: 5.56), and a higher level of procalcitonin (PCT) (OR: 1.05) on admission were statistically associated to an increased risk of developing meningitis. Compared to 114 patients with NTS infections, 16 patients with typhoid fever presented with higher levels of CRP and PCT (P < 0.05). The rates of resistance to ampicillin, sulfamethoxazole/trimethoprim, ciprofloxacin, and ceftriaxone among Salmonella Typhi and NTS isolates were 50% vs 57.3%, 9.1% vs 24.8%, 0% vs 11.2%, and 0% vs 9.9%, respectively. NTS has been the major cause of invasive Salmonella infections in Chinese children and can result in severe diseases. Antimicrobial resistance among NTS was more common.

Paediatric Osteomyelitis and Septic Arthritis Pathogen Distribution and Antimicrobial Resistance in a Single Centre: A 15-Year Retrospective Analysis

BACKGROUND

The epidemiological characteristics of the common pathogens underlying acute haematogenous osteoarticular infection (AHOI) and their resistance to drugs have temporal and regional differences.

AIMS

To determine the antimicrobial treatment most effective for culture-negative AHOI patients and those without bacterial cultures.

METHODS

Retrospective analysis of clinical data of children with AHOI who were culture positive from January 2007 to December 2021. And the distribution of the main pathogens and the drug resistance Staphylococcus aureus were analysed in different time periods, age groups and infection types.

RESULTS

A total of 188 cases met the inclusion criteria, including 97 cases of acute haematogenous osteomyelitis (AHO), 75 cases of septic arthritis (SA) and 16 cases of AHO concomitant with SA. The commonest causative pathogen in local children was S. aureus of Gram-positive cocci, followed by Streptococcus, and occasionally Gram-negative bacilli. The distribution of S. aureus had no significant correlation with age or infection type. Staphylococcus aureus accounted for 81.82%, 90.91% and 96.15% of all pathogens, and methicillin-resistant S. aureus (MRSA) accounted for 24.22%, 53.33% and 76.00% of S. aureus in 2007-11, 2012-16 and 2017-21, respectively. The frequency of MRSA infection showed an increasing trend over time.

CONCLUSION

Staphylococcus aureus is still the main pathogen of AHOI in local children. The proportion of MRSA in S. aureus has also increased over time to 76% in the last 5 years, and the increased proportion of MRSA can affect the choice of initial empirical medication.

Stenotrophomonas maltophilia Infections in Pediatric Patients - Experience at a European Center for Pediatric Hematology and Oncology

Stenotrophomonas maltophilia is an important nosocomial pathogen in immunocom-promised individuals and characterized by intrinsic resistance to broad-spectrum antibacterial agents. Limited data exists on its clinical relevance in immunocompromised pediatric patients, particularly those with hematological or oncological disorders. In a retrospective single center cohort study in pediatric patients receiving care at a large european pediatric hematology and oncology department, ten cases of invasive S.maltophilia infections (blood stream infections (BSI), 4; BSI and pneumonia, 3, or soft tissue infection, 2; and pneumonia, 1) were identified between 2010 and 2020. Seven patients had lymphoblastic leukemia and/or were post allogeneic hematopoietic cell transplantation. Invasive S.maltophilia infections occurred in a setting of indwelling central venous catheters, granulocytopenia, defective mucocutaneous barriers, treatment with broad-spectrum antibacterial agents, and admission to the intensive care unit. Whole genome sequencing based typing revealed no genetic relationship among four individual S.maltophilia isolates. The case fatality rate and mortality at 100 days post diagnosis were 40 and 50%, respectively, and three patients died from pulmonary hemorrhage. Invasive S.maltophilia infections are an emerging cause of infectious morbidity in patients receiving care at departments of pediatric hematology and oncology and carry a high case fatality rate.

Genomic Epidemiology of Multidrug-Resistant Nontyphoidal Salmonella in Young Children Hospitalized for Gastroenteritis

Nontyphoidal Salmonella (NTS) gastroenteritis in children remains a significant burden on health care and constitutes a majority of all admissions for Salmonella infections in public hospitals in Hong Kong. In this prospective study, 41% of 241 children hospitalized with gastroenteritis from three public hospitals during 2019 were culture confirmed to have NTS infection. These Salmonella isolates were whole-genome sequenced and in silico predicted for their serovars/serotypes using the Salmonella In Silico Typing Resource (SISTR) and SeqSero1, and the antimicrobial resistance (AMR) genes were determined. Phylogenetic analysis revealed three major clades belonging to Salmonella enterica serovar Enteritidis sequence type 11 (ST11) (43%), multidrug-resistant (MDR) S. Typhimurium ST19 (12%) and its monophasic variant ST34 (25%), and mostly singletons of 15 other serovars. MDR S. Typhimurium and its variant were more common in infants <24 months of age and possessed genotypic resistance to five antimicrobial agents, including ampicillin (A), chloramphenicol (C), aminoglycosides (Am), sulfonamides (Su), and tetracyclines (T). Older children were more often infected with S. Enteritidis, which possessed distinct genotypic resistance to AAmSu and fluoroquinolones. In addition, 3% of the isolates possessed extended-spectrum beta-lactamase (ESBL) CTX-M genes, while one isolate (1%) harboring the carbapenemase gene blaNDM-1 was identified. Our findings provide a more complete genomic epidemiological insight into NTS causing gastroenteritis and identify a wider spectrum of determinants of resistance to third-generation beta-lactams and carbapenems, which are often not readily recognized. With high rates of multidrug-resistant NTS from studies in the Asia-Pacific region, the rapid and reliable determination of serovars and resistance determinants using whole-genome sequencing (WGS) is invaluable for enhancing public health interventions for infection prevention and control. IMPORTANCE Nontyphoidal Salmonella (NTS) gastroenteritis is a foodborne disease with a large global burden. Antimicrobial resistance (AMR) among foodborne pathogens is an important public health concern, and multidrug-resistant (MDR) Salmonella is prevalent in Southeast Asia and China. Using whole-genome sequencing, this study highlights the relationship of the MDR Salmonella serotypes and the diverse range of Salmonella genotypes that contaminate our food sources and contribute to disease in this locality. The findings update our understanding of Salmonella epidemiology and associated MDR determinants to enhance the tracking of foodborne pathogens for public health and food safety.

Invasive Klebsiella pneumoniae Infections in Community-Settings and Healthcare Settings

Objective

To assess clinical characteristics, outcomes and antimicrobial resistance of invasive Klebsiella pneumoniae (KP) infections in Chinese pediatric patients in hospital and community settings.

Methods

This retrospective study was conducted in the nine tertiary hospitals during 2016–2018. The 324 pediatric inpatients who had KP isolated from blood and cerebrospinal fluid and had complete medical records reviewed were included. We analyzed the risk factors, outcomes and antimicrobial resistance pattern of KP-infected patients based on comparison between healthcare-associated KP infections (HAI) and community-acquired infections.

Results

Of the 324 enrolled patients, 275 (84.9%) were clinically defined as HAI, including 175 (63.6%) neonates and 100 (36.4%) aged >28 days. The overall prevalence of CRKP was 38.2% (43.4% in HAI verse 8.7% in CAI, P <0.05). Prematurity (odds ratio (OR): 37.07, 95% CI: 8.29–165.84), hematologic malignancies (OR: 15.52, 95% CI: 1.89–127.14) and invasive mechanical ventilation (OR: 13.09, 95% CI: 1.66–103.56) were independent risk factors for HAI. Patients from rural area (OR: 1.94, 95% CI: 1.12–3.35), invasive mechanical ventilation (OR: 2.33, 95% CI: 1.25–4.33), antibiotic therapy prior to admission (OR: 2.33, 95% CI: 1.25–4.33) and prior hospital stay in the past 30 days (OR: 3.46, 95% CI: 1.87–6.41) were associated with healthcare-associated CRKP infections. Organ dysfunction was independently correlated with poor outcomes (OR: 2.92, 95% CI: 1.23–6.95).

Conclusion

Pediatric invasive KP infections and high prevalence of CRKP infections largely occurred in healthcare settings in China. The adequate and intensified infection control measures should be focused on high-risk hematologic patients, neonatal patients and intubated patients.