Neonatal Sepsis: The Impact of Carbapenem-Resistant and Hypervirulent Klebsiella pneumoniae

Changing Landscape of Antimicrobial Resistance in Neonatal Sepsis: An in silico Analyses of Multidrug Resistance in Klebsiella pneumoniae

BACKGROUND

Neonatal sepsis poses a critical healthcare concern, as multidrug-resistant Klebsiella pneumoniae ( K. pneumoniae ) infections are on the rise. Understanding the antimicrobial susceptibility patterns and underlying resistance mechanism is crucial for effective treatment.

OBJECTIVES

This study aimed to comprehensively investigate the antimicrobial susceptibility patterns of K. pneumoniae strains responsible for neonatal sepsis using in silico tools. We sought to identify trends and explore reasons for varying resistance levels, particularly for β-lactams and fluoroquinolone.

METHODS

K. pneumoniae isolated from neonates at Kanchi Kamakoti CHILDS Trust Hospital (2017-2020) were analyzed for antimicrobial resistance. Elevated resistance to β-lactam and fluoroquinolone antibiotics was further investigated through molecular docking and interaction analysis. β-lactam affinity with penicillin-binding proteins and β-lactamases was examined. Mutations in ParC and GyrA responsible for quinolone resistance were introduced to investigate ciprofloxacin interactions.

RESULTS

Of 111 K. pneumoniae blood sepsis isolates in neonates, high resistance was detected to β-lactams such as cefixime (85.91%, n = 71), ceftriaxone (84.9%, n = 106), cefotaxime (84.9%, n = 82) and fluoroquinolone (ciprofloxacin- 79.44%, n = 107). Molecular docking revealed low β-lactam binding toward penicillin-binding proteins and higher affinities for β-lactamases, attributing to the reduced β-lactam efficiency. Additionally, ciprofloxacin showed decreased affinity toward mutant ParC and GyrA in comparison to their corresponding wild-type proteins.

CONCLUSION

Our study elucidates altered resistance profiles in neonatal sepsis caused by K. pneumoniae , highlighting mechanisms of β-lactam and fluoroquinolone resistance. It underscores the urgent need for the development of sustainable therapeutic alternatives to address the rising antimicrobial resistance in neonatal sepsis.

Shift in the dominant sequence type of carbapenem-resistant Klebsiella pneumonia infection from ST278-NDM-1 to ST11-KPC-2 in neonatal patients in a children's hospital in Shanghai, China, 2017-2021

OBJECTIVES

To investigate the clinical characteristics and molecular epidemiology of CRKP infection in neonatal patients in a children's hospital in China from 2017 to 2021.

METHODS

Species identification and antibiotic susceptibilities were tested with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and VITEK 2 systems. The clinical data were collected from medical records. Carbapenem-resistant Klebsiella pneumoniae (CRKP) isolates were investigated by antimicrobial susceptibility testing, carbapenemase genes and multilocus sequence typing.

RESULTS

Six kinds of resistant genes and 23 STs were detected. BlaNDM-1 (n=83, 55.3%) was the predominant carbapenemase gene, followed by blaKPC-2 (n=45, 30.0%), blaNDM-5 (n=7, 4.7%), blaIMP-38 (n=6, 4.0%). BlaNDM-1 was predominant in 2017 and 2018, whereas blaKPC-2 increased in 2019 and became the predominant gene from 2020 to 2021. ST11 accounted for most infections (n=35, 23.3%), followed by ST278 (n=23, 15.3%), ST17 (n=17, 11. 3%) and ST2735 (n=16, 10.7%). ST278 and ST17 were predominant in 2017 and 2018, whereas ST11 increased in 2019 and became the predominant sequence type from 2020 to 2021. Compared with blaNDM-1, the CRKP strains producing blaKPC-2 were characterized by high resistance to gentamicin, amikacin and levofloxacin and the change trend of drug resistance rate before and after COVID-19 was consistent with that of blaNDM-1 and blaKPC-2.

CONCLUSIONS

The main sequence type of CRKP infection changed dynamically from ST278-NDM-1 to ST11-KPC-2 during the years 2017-2021 in the newborns. Antibiotic exposure and the prevalence of COVID-19 since 2020 may have led to changes in hospital population and lead to the changes.

Microbial Pattern of Neonatal Sepsis in the Neonatal Intensive Care Unit of dr. Ramelan Navy Central Hospital

Background

The morbidity and mortality rates from neonatal sepsis remain high. However, there is limited information about the microbial pattern of neonatal sepsis in Indonesia. Microbial patterns can give an overview of the hygiene of an environment and act as a determinant for choosing definitive antibiotic treatment in neonatal sepsis patients. The organisms that cause neonatal sepsis differ from unit to unit and from time to time within the same unit.

Objectives

This study is aimed at discovering the microbial pattern of neonatal sepsis in the Neonatal Intensive Care Unit (NICU), dr. Ramelan Navy Central Hospital, in 2021-2022.

Methods

This is a retrospective, cross-sectional study that takes secondary data from the NICU and clinical microbiology department of dr. Ramelan Navy Central Hospital. Data that met the inclusion and exclusion criteria available between January 1, 2021, and December 31, 2022, were collected. Patients whose blood cultures were positive for bacterial growth and diagnosed with sepsis were selected as the study sample.

Results

Out of 174 samples, 93 (53.4%) were found positive for bacterial infection and diagnosed as neonatal sepsis. Gram-negative isolates (96.8%) were predominant. Sixty-point-two percent of Klebsiella pneumoniae XDR, 19.4% of Klebsiella pneumoniae ESBL, and 8.6% of Burkholderia cepacia XDR were identified. The gram-positive isolates found in this study were only 3 samples (3.2%). Two-point-one percent of MRSA and 1.1% of Staphylococcus haemolyticus MDR were identified.

Conclusion

The most common microorganisms causing neonatal sepsis in our NICU were gram-negative bacteria, particularly Klebsiella pneumoniae XDR. Following the recommended infection control procedures, practicing good hand hygiene, and having access to basic supplies and equipment are important to prevent and reduce the incidence of sepsis.

Hypervirulent Klebsiella pneumoniae in a South African tertiary hospital-Clinical profile, genetic determinants, and virulence in Caenorhabditis elegans

Introduction

A distinct strain of Klebsiella pneumoniae (K. pneumoniae) referred to as hypervirulent (hvKp) is associated with invasive infections such as pyogenic liver abscess in young and healthy individuals. In South Africa, limited information about the prevalence and virulence of this hvKp strain is available. The aim of this study was to determine the prevalence of hvKp and virulence-associated factors in K. pneumoniae isolates from one of the largest tertiary hospitals in a South African province.

Methods

A total of 74 K. pneumoniae isolates were received from Pelonomi Tertiary Hospital National Health Laboratory Service (NHLS), Bloemfontein. Virulence-associated genes (rmpA, capsule serotype K1/K2, iroB and irp2) were screened using Polymerase Chain Reaction (PCR). The iutA (aerobactin transporter) gene was used as a primary biomarker of hvKp. The extracted DNAs were sequenced using the next-generation sequencing pipeline and the curated sequences were used for phylogeny analyses using appropriate bioinformatic tools. The virulence of hvKp vs. classical Klebsiella pneumoniae (cKp) was investigated using the Caenorhabditis elegans nematode model.

Results

Nine (12.2%) isolates were identified as hvKp. Moreover, hvKp was significantly (p < 0.05) more virulent in vivo in Caenorhabditis elegans relative to cKp. The virulence-associated genes [rmpA, iroB, hypermucoviscous phenotype (hmv) phenotype and capsule K1/K2] were significantly (p < 0.05) associated with hvKp. A homology search of the curated sequences revealed a high percentage of identity between 99.8 and 100% with other homologous iutA gene sequences of other hvKp in the GenBank.

Conclusion

Findings from this study confirm the presence of hvKp in a large tertiary hospital in central South Africa. However, the low prevalence and mild to moderate clinical presentation of infected patients suggest a marginal threat to public health. Further studies in different settings are required to establish the true potential impact of hvKp in developing countries.

Changing Patterns of Organisms Causing Neonatal Sepsis and Their Antimicrobial Sensitivity Profile in a Tertiary Center - A Prospective Study

OBJECTIVE

To identify the profile of organisms causing neonatal sepsis and their antibiotic susceptibility pattern in recent years.

METHODS

In this prospective study, authors included neonates with blood culture proven sepsis. Antibiotic resistance patterns that were identified were extended spectrum β-lactamase, AmpC β-lactamase and possible carbapenamase producer. Xpert CARBA-R test was performed to identify genes causing carbapenem resistance.

RESULTS

There were 210 neonates with 216 episodes of blood culture proven sepsis. Klebsiella pneumoniae (n = 85) and Escherichia coli (n = 19) were the most common gram-negative organisms. Coagulase negative Staphylococcus (n = 11) and Staphylococcus aureus (n = 7) were the most common gram positive organisms. There were 17 episodes of fungal sepsis with Candida albicans (n = 6) being the most common. Sixty-five out of 216 (30%) organisms were multidrug resistant. Among the Klebsiella isolates, 32/85 (37.6%) were possible carbapenamase producers. Xpert CARBA-R performed for 13 infants showed that all were positive for New Delhi metallo-β-lactamase. Among the 19 Escherichia coli, 10/19 (37.6%) were multidrug resistant and 1/19 (5.3%) was a possible carbapenamase producer.

CONCLUSIONS

The authors found a significant increase in New Delhi metallo-β-lactamase positive Klebsiella pneumoniae causing neonatal sepsis in last three years. Regular monitoring of resistance patterns and prudent use of antimicrobials are imperative in regulating the shadow pandemic of multi-drug resistant neonatal sepsis.

[A cross-sectional study on the pathogen composition and antimicrobial resistance in neonates with sepsis in Hebei Province, China]

OBJECTIVES

To study the pathogen composition and antimicrobial resistance characteristics in neonates with sepsis in the Hebei area, providing a basis for optimizing the management strategies for neonatal sepsis in the region.

METHODS

The medical data of neonates with sepsis confirmed by blood culture from 23 hospitals in Hebei Province were collected prospectively from November 1, 2021 to December 31, 2022. The pathogen composition and antimicrobial resistance characteristics were analyzed in early-onset sepsis (EOS), community-acquired late-onset sepsis (CALOS), and hospital-acquired late-onset sepsis (HALOS) cases.

RESULTS

A total of 289 neonates were included, accounting for 292 infection episodes, with 117 (40.1%) EOS, 95 (32.5%) CALOS, and 80 (27.4%) HALOS cases. A total of 294 pathogens were isolated, with 118 (40.1%) from the EOS group, where Escherichia coli (39 strains, 33.0%) and coagulase-negative staphylococci (13 strains, 11.0%) were the most common. In the CALOS group, 95 pathogens were isolated (32.3%), with Escherichia coli (35 strains, 36.8%) and group B Streptococcus (14 strains, 14.7%) being predominant. The HALOS group yielded 81 isolates (27.6%), with Klebsiella pneumoniae (24 strains, 29.6%) and Escherichia coli (21 strains, 25.9%) as the most frequent. Coagulase-negative staphylococci showed over 80% resistance to penicillin antibiotics. Escherichia coli and Klebsiella pneumoniae showed a resistance rate of 2.2% to 75.0% to common β-lactam antibiotics. The resistance rates of predominant Gram-negative bacteria in the HALOS group to common β-lactam antibiotics were higher than those in the CALOS group.

CONCLUSIONS

In the Hebei region, Escherichia coli is the most common pathogen in both EOS and LOS. There are differences in the composition and antimicrobial resistance of pathogens among different types of neonatal sepsis. The choice of empirical antimicrobial drugs should be based on the latest surveillance data from the region.

Colonisation of hospital surfaces from low- and middle-income countries by extended spectrum β-lactamase- and carbapenemase-producing bacteria

Hospital surfaces can harbour bacterial pathogens, which may disseminate and cause nosocomial infections, contributing towards mortality in low- and middle-income countries (LMICs). During the BARNARDS study, hospital surfaces from neonatal wards were sampled to assess the degree of environmental surface and patient care equipment colonisation by Gram-negative bacteria (GNB) carrying antibiotic resistance genes (ARGs). Here, we perform PCR screening for extended-spectrum β-lactamases (blaCTX-M-15) and carbapenemases (blaNDM, blaOXA-48-like and blaKPC), MALDI-TOF MS identification of GNB carrying ARGs, and further analysis by whole genome sequencing of bacterial isolates. We determine presence of consistently dominant clones and their relatedness to strains causing neonatal sepsis. Higher prevalence of carbapenemases is observed in Pakistan, Bangladesh, and Ethiopia, compared to other countries, and are mostly found in surfaces near the sink drain. Klebsiella pneumoniae, Enterobacter hormaechei, Acinetobacter baumannii, Serratia marcescens and Leclercia adecarboxylata are dominant; ST15 K. pneumoniae is identified from the same ward on multiple occasions suggesting clonal persistence within the same environment, and is found to be identical to isolates causing neonatal sepsis in Pakistan over similar time periods. Our data suggests persistence of dominant clones across multiple time points, highlighting the need for assessment of Infection Prevention and Control guidelines.

Nanomaterial-based methods for sepsis management

Sepsis is a serious disease caused by an impaired host immune response to infection, resulting in organ dysfunction, tissue damage and is responsible for high in-hospital mortality (approximately 20%). Recently, WHO documented sepsis as a global health priority. Nevertheless, there is still no effective and specific therapy for clinically detecting sepsis. Nanomaterial-based approaches have appeared as promising tools for identifying bacterial infections. In this review, recent biosensors are introduced and summarized as nanomaterial-based platforms for sepsis management and severe complications. Biosensors can be used as tools for the diagnosis and treatment of sepsis and as nanocarriers for drug delivery. In general, diagnostic methods for sepsis-associated bacteria, biosensors developed for this purpose are presented in detail, and their strengths and weaknesses are discussed. In other words, readers of this article will gain a comprehensive understanding of biosensors and their applications in sepsis management.

[Clinical practice guidelines for meropenem therapy in neonatal sepsis (2024)]

Meropenem is one of the most widely used special-grade antimicrobial agents in the treatment of neonatal sepsis. However, its irrational use has led to an increasingly severe problem of bacterial multidrug resistance. The guideline was developed following standardized methods and procedures, and provides 12 recommendations specifically addressing 9 clinical issues. The recommendations cover various aspects of meropenem use in neonates, including timing of administration, recommended dosage, extended infusion, monitoring and assessment, antimicrobial adjustment strategies, treatment duration, and treatment strategies for carbapenem-resistant Enterobacteriaceae infections. The aim of the guideline is to provide evidence-based recommendations and guidance for the rational use of meropenem in neonates with sepsis.

Intense Intestinal Carriage of Carbapenemase-Producing Klebsiella pneumoniae Co-harboring OXA-48, KPC, VIM, and NDM Among Preterm Neonates in a Moroccan Neonatal Intensive Care Unit

INTRODUCTION

This study aimed to investigate the prevalence and the carbapenemase production ability of Klebsiella pneumoniae isolates from premature neonates' intestinal tracts in a Moroccan neonatal intensive care unit Methodology: Active rectal screening was performed among 339 preterm infants. The collected isolates were subjected to antibiotic susceptibility testing, phenotypic analysis of carbapenemase production, and molecular detection of carbapenemase genes.

RESULTS

Out of 293 K. pneumoniae isolates collected, 31.05% (91) were resistant to carbapenem and produced carbapenemase, resulting in a 22.12% rate of intestinal carriage. Among the carbapenem-resistant K. pneumoniae isolates, 40.65% (37) had co-harbored carbapenemase genes. All isolates contained the blaOXA-48 gene, and the blaNDM, blaVIM, and blaKPC genes were detected in 30.76%, 9.89%, and 2.19% of the isolates, respectively. Out of 30.76% of these isolates had both the blaOXA-48 and blaNDM genes, 8.79% had both blaOXA-48 and blaVIM, and only 2.20% had both blaOXA-48 and blaKPC genes. Furthermore, 88.57% of carbapenem-resistantK. pneumoniae isolates co-harboring carbapenemase genes were genetically related strains.

CONCLUSIONS

This study revealed a high prevalence of intestinal carriage of carbapenem-resistant K. pneumoniae. Therefore, implementing effective screening and diagnostic measures, and focusing on antimicrobial stewardship are essential to preventing the spread of these resistant strains and minimizing the risk they pose to premature infants.

Carbapenem-resistant Klebsiella pneumoniae Osteoarthritis in Two Preterm Infants Treated With Ceftazidime-avibactam

BACKGROUND

The emergence of carbapenem-resistant Klebsiella pneumoniae (CRKP) poses a major threat to global public health. CRKP infections are challenging to treat owing to the limited number of antibiotic species, especially in preterm infants. Ceftazidime-avibactam (CAZ-AVI) is a novel antibiotic with activity against CRKP. At present, there have been no reports of using CAZ-AVI to treat osteoarthritis in premature infants.

METHODS

We describe 2 preterm infants with CRKP osteoarthritis treated with CAZ-AVI in a tertiary children's hospital in China. Clinical characteristics, laboratory and microbiologic data, treatment and follow-up information were retrospectively collected and analyzed.

RESULTS

The 2 cases were both premature infants who contracted sepsis and CRKP osteoarthritis. Meropenem and polymyxin B were initially chosen for the first infant. CAZ-AVI was then used due to persistent infection. The second infant was commenced immediately on CAZ-AVI after receipt of antimicrobial susceptibility on the 4th day after admission. Both recovered with CAZ-AVI (50 mg/kg q8h) and surgical incision and drainage. Neither had a joint deformity or limb length discrepancy at 36 and 34 months, respectively.

CONCLUSIONS

This is the first report on the use of CAZ-AVI to treat CRKP osteoarthritis in premature infants. Successful treatment depends on prompt recognition of the pathogen and treatment with a combination of antibiotics with or without surgery. Further study is needed to determine the pharmacokinetics and pharmacodynamics of CAZ-AVI for treating preterm infants with serious CRKP osteoarthritis.

Crippling of Klebsiella pneumoniae virulence by metformin, N-acetylcysteine and secnidazole

INTRODUCTION

The emergence of multidrug-resistant Klebsiella pneumoniae in hospitals represents a serious threat to public health. Infections caused by Klebsiella pneumoniae are widespread in healthcare institutions, mainly pneumonia, bloodstream infections, and infections affecting neonates in intensive care units; so, it is necessary to combat this pathogen with new strategies. Targeting virulence factors necessary to induce host damage and disease is a new paradigm for antimicrobial therapy with several potential benefits that could lead to decreased resistance.

BACKGROUND

The influence of metformin, N-acetylcysteine, and secnidazole on Klebsiella pneumoniae virulence factors production was tested. The production of Klebsiella pneumoniae virulence factors such as biofilm formation, urease, proteases, hemolysins, and tolerance to oxidative stress was evaluated phenotypically using sub-inhibitory concentration (1/8 MIC) of metformin, N-acetylcysteine, and secnidazole. For more confirmation, qRT-PCR was used to assess the relative expression level of rmpA, wcaG, fimH-1, mrkD, ureA, and khe genes regulating virulence factors production.

RESULTS

Metformin, N-acetylcysteine, and secnidazole were all found to have a powerful inhibitory effect on the production of virulence factors phenotypically. Our results showed a significant reduction in the expression level of rmpA, wcaG, fimH-1, mrkD, ureA, and khe genes. Furthermore, the tested drugs were investigated in vivo to inform their ability to protect mice against Klebsiella pneumoniae pathogenesis.

CONCLUSIONS

Metformin, N-acetylcysteine, and secnidazole inhibited the virulence of Klebsiella pneumoniae. Besides combating resistant Klebsiella pneumoniae, the tested drugs could also serve as an adjuvant to traditional antibiotics.

Prevalence of gram-negative bacteria and their antibiotic resistance in neonatal sepsis in Iran: a systematic review and meta-analysis

BACKGROUND

Neonatal sepsis, particularly gram-negative (GN) bacteria-induced, is a significant cause of morbidity and mortality in newborns. Healthcare professionals find this issue challenging because of antibiotic resistance. This study aims to combine findings to identify the prevalence of GN bacteria and their antibiotic resistance in Iranian neonates with sepsis.

METHODS

This systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). The literature search was performed through international databases, including (PubMed/MEDLINE, EMBASE, Scopus, and Web of Science), Iranian local databases (Magiran, Iranmedex, Irandoc, Scimed, and SID), and the first 100 records of Google Scholar. Analytical cross-sectional study checklist from the Joanna Briggs Institute (JBI) was used for the quality assessment of included studies. Comprehensive Meta-Analysis Software Version 2 was used to conduct the meta-analysis. The between-study heterogeneity was investigated by I2 statistics.

RESULTS

The prevalence of GN bacteria was estimated to be 53.6% [95% CI: 45.9- 61.1: P = 0.362] in Iranian neonates with sepsis, based on 31 studies with a sample size of 104,566. klebsiella pneumoniae (K.pneumonia) (23.2% [95% CI: 17.5-30.0, P < 0.001]) followed by Escherichia coli (E.coli) (13.5% [95% CI: 9.4-18.9, P < 0.001]) were more prevalent among GN bacteria. The highest resistance in K.pneumoniae was observed in Cefixime (80.6%, [95% CI: 56.3-93.1, P = 0.018]). E.coli showed greater resistance to Ampicillin (61.8%, [95% CI: 44.2-76.5, P = 0.188]. The prevalence of GN bacteria in Iranian neonates with sepsis has a decreasing trend based on the year, as shown by a meta-regression model (P < 0.0004).

CONCLUSION

GN pathogens, particularly K.pneumoniae, and E.coli, are the leading cause of neonatal sepsis in Iran. GN bacteria showed the highest resistance to Third-generation cephalosporin and Aminoglycosides.

Bacteriological profiles and antibiotic susceptibility of neonatal sepsis in a university hospital of Northern India

Context

Knowledge of epidemiology of bacterial isolates and their anti-biograms in hospital settings is necessary for prompt empirical anti-microbial therapy of neonatal sepsis.

Aims

To study risk factors, bacteriological profiles, and anti-biograms of blood culture isolates of both early and late onset neonatal sepsis.

Settings and Design

It is a prospective observational study conducted from January 2020 till July 2021 at our tertiary care center.

Material and Methods

Neonates (0-28 days) admitted to this neonatal intensive care unit clinically suspected with sepsis were subjected to blood cultures, and the isolates were identified both biochemically and by the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry system. Antibiotic susceptibility testing (AST) was performed as per CLSI guidelines.

Statistical Analysis

Chi-square test was used.

Results

Out of 280 suspected cases of neonatal sepsis, 43 (15.3%) cases showed positive blood culture. Of these, the majority (30, 69.8%) had late-onset neonatal sepsis. Major pre-disposing risk factors were pre-term birth and a low birth weight (26, 60.5%). Gram-negative bacteria and Gram-positive bacteria were isolated in 25 (58.1%) and 18 (41.9%) blood cultures, respectively. Klebsiella pneumoniae (37.5%) was the most predominant pathogen in both early-onset (23.1%) and late-onset (46.7%) sepsis. Coagulase negative Staphylococcus (34.8%) was the second most common organism and was more common in late onset (23.2%) neonatal sepsis. A high level of antibiotic resistance was noted in Klebsiella pneumoniae isolates, even to amikacin (76.5%) and carbapenems (66.7%).

Conclusion

Increased resistance in bacterial isolates of neonatal sepsis emphasizes the need of AST of bacterial isolates for proper antibiotic administration.

Hypervirulent Klebsiella pneumoniae Causing Neonatal Bloodstream Infections: Emergence of NDM-1-Producing Hypervirulent ST11-K2 and ST15-K54 Strains Possessing pLVPK-Associated Markers

Klebsiella pneumoniae is a major cause of neonatal sepsis. Hypervirulent Klebsiella pneumoniae (hvKP) that cause invasive infections and/or carbapenem-resistant hvKP (CR-hvKP) limit therapeutic options. Such strains causing neonatal sepsis have rarely been studied. Characterization of neonatal septicemic hvKP/CR-hvKP strains in terms of resistance and virulence was carried out. Antibiotic susceptibility, molecular characterization, evaluation of clonality, in vitro virulence, and transmissibility of carbapenemase genes were evaluated. Whole-genome sequencing (WGS) and mouse lethality assays were performed on strains harboring pLVPK-associated markers. About one-fourth (26%, 28/107) of the studied strains, leading to mortality in 39% (11/28) of the infected neonates, were categorized as hvKP. hvKP-K2 was the prevalent pathotype (64.2%, 18/28), but K54 and K57 were also identified. Most strains were clonally diverse belonging to 12 sequence types, of which ST14 was most common. Majority of hvKPs possessed virulence determinants, strong biofilm-forming, and high serum resistance ability. Nine hvKPs were carbapenem-resistant, harboring blaNDM-1/blaNDM-5 on conjugative plasmids of different replicon types. Two NDM-1-producing high-risk clones, ST11 and ST15, had pLVPK-associated markers (rmpA, rmpA2, iroBCDEN, iucABCDiutA, and peg-344), of which one co-transferred the markers along with blaNDM-1. The 2 strains revealed high inter-genomic resemblance with the other hvKP reference genomes, and were lethal in mouse model. To the best of our knowledge, this study is the first to report on the NDM-1-producing hvKP ST11-K2 and ST15-K54 strains causing fatal neonatal sepsis. The presence of pLVPK-associated markers and blaNDM-1 in high-risk clones, and the co-transmission of these genes via conjugation calls for surveillance of these strains. IMPORTANCE Klebsiella pneumoniae is a leading cause of sepsis in newborns and adults. Among the 2 major pathotypes of K. pneumoniae, classical (cKP) and hypervirulent (hvKP), hvKP causes community-acquired severe fatal invasive infections in even healthy individuals, as it possesses several virulence factors. The lack of comprehensive studies on neonatal septicemic hvKPs prompted this work. Nearly 26% diverse hvKP strains were recovered possessing several resistance and virulence determinants. The majority of them exhibited strong biofilm-forming and high serum resistance ability. Nine of these strains were also carbapenem (last-resort antibiotic)-resistant, of which 2 high-risk clones (ST11-K2 and ST15-K54) harbored markers (pLVPK) noted for their virulence, and were lethal in the mouse model. Genome-level characterization of the high-risk clones showed resemblance with the other hvKP reference genomes. The presence of transmissible carbapenem-resistant gene, blaNDM, along with pLVPK-markers calls for vigilance, as most clinical microbiology laboratories do not test for them.

Horizontal Gene Transfer of Antibiotic Resistance Genes in Biofilms

Most bacteria attach to biotic or abiotic surfaces and are embedded in a complex matrix which is known as biofilm. Biofilm formation is especially worrisome in clinical settings as it hinders the treatment of infections with antibiotics due to the facilitated acquisition of antibiotic resistance genes (ARGs). Environmental settings are now considered as pivotal for driving biofilm formation, biofilm-mediated antibiotic resistance development and dissemination. Several studies have demonstrated that environmental biofilms can be hotspots for the dissemination of ARGs. These genes can be encoded on mobile genetic elements (MGEs) such as conjugative and mobilizable plasmids or integrative and conjugative elements (ICEs). ARGs can be rapidly transferred through horizontal gene transfer (HGT) which has been shown to occur more frequently in biofilms than in planktonic cultures. Biofilm models are promising tools to mimic natural biofilms to study the dissemination of ARGs via HGT. This review summarizes the state-of-the-art of biofilm studies and the techniques that visualize the three main HGT mechanisms in biofilms: transformation, transduction, and conjugation.

Amp-CKlebsiella-Induced Chorioamnionitis and Associated Abnormalities in Cardiotocography: A Case Report with a Narrative Review

Introduction. Infections caused by multidrug-resistant organisms are on the rise in obstetric patients. Chorioamnionitis is associated with adverse pregnancy outcomes. If caused by multidrug-resistant organisms, chorioamnionitis is associated with high maternal and fetal morbidity. Due to the paucity of the literature and the challenges associated with their diagnosis, the diagnosis is usually delayed. This often leads to delays in management, and hence, adverse maternal and neonatal outcomes are noted. Important Clinical Findings. The patient presented with prelabour rupture of membranes for three days. She developed chorioamnionitis in labour, which was refractory to broad spectrum antibiotics. Persistent tachycardia with variable decelerations followed by prolonged fetal deceleration was observed in cardiotocography. Delivery of baby was done by cesarean section in the view of pathological findings in cardiotocography. The primary diagnoses, interventions, and outcomes. Based on the placental culture results, Amp-C Klebsiella-induced chorioamnionitis was diagnosed. Ertapenem was commenced after the sensitivity results. Good feto-maternal outcomes were observed. The neonate was admitted to the neonatal intensive care unit and discharged home in stable condition. Conclusions. Cases of multidrug-resistant organisms-induced chorioamnionitis are rarely reported, though they are associated with maternal morbidity and poor neonatal outcome. In cases of chorioamnionitis, caution should be taken in cases that are refractory to broad-spectrum antibiotics, and multidrug-resistant organisms should be suspected and managed to improve pregnancy outcome.

Successful Control of an Outbreak by Phenotypically Identified Extended-Spectrum Beta-Lactamase–Producing Klebsiella pneumoniae in a Neonatal Intensive Care Unit

Background: Premature newborns represent a vulnerable population, at high risk of acquiring nosocomial infections during neonatal intensive care unit (NICU) admission. Multidrug-resistant organisms represent the greatest concern due to their intrinsic virulence and the limited therapeutic options. Resistant Enterobacterales are a growing threat for critically ill neonates, with increasing numbers of NICU outbreaks caused by extended-spectrum beta-lactamase (ESBL)-producing Enterobacterales being described. This study reports the early detection and successful control of an outbreak caused by ESBL-producing Klebsiella pneumoniae (ESBL-KP) in an Italian NICU in February 2021. Results: A total of 13 newborns tested positive for ESBL-KP between 2–9 February 2021, of whom four (31%) had a bloodstream infection. Two were critically ill, extremely premature newborns who died because of multiple comorbidities, and two were cured after treatment with meropenem. All other patients survived and were either discharged home or moved to other hospitals/wards in good clinical condition. ESBL-KP ST45 was found in all isolates by multilocus sequence typing (MLST) analysis. An outbreak control plan was set, including surveillance cultures for all neonates, NICU environments, and medical devices, along with the extended use of contact precautions and cohorting. In addition, the infection control plan was carried out through reinforcement and enhancement measures to guarantee maximal compliance. The outbreak was successfully controlled in seven days, given that no further cases were identified after 9 February. The source of the ESBL-KP outbreak was not identified through environmental sampling. Conclusions: Thanks to multidisciplinary management, a threatening outbreak of ESBL-KP in a NICU was controlled in few days. The prompt recognition of the event onset and the adoption of infection control interventions helped contain the bacteria spread on the ward.

Molecular epidemiology and mechanism of Klebsiella pneumoniae resistance to ertapenem but not to other carbapenems in China

Resistance to only ertapenem is an unusual phenotype of carbapenem-resistant Klebsiella pneumoniae (CRKP). This study aimed to investigate the molecular epidemiology and underlying mechanism involved in ertapenem resistance of K. pneumoniae strains that are susceptible to meropenem and imipenem. Among the 697 K. pneumoniae strains isolated from 11 grade A hospitals in China, 245 were CRKP strains, of which 18 strains resistant only to ertapenem were isolated. The genotypes, phenotypes, drug resistance homology, and drug sensitivity were analyzed; moreover, the expressions of efflux pump components and outer membrane proteins were assessed. The whole genomes of these 18 strains were sequenced and analyzed for mutations leading to drug resistance. The results revealed that ertapenem resistance may be related to ramR mutation. The function of ramR was confirmed using gene complementation to the original strain to determine the mechanism underlying ertapenem resistance of K. pneumoniae strains. In total, 7.4% of the tested CRKP strains were resistant only to ertapenem. None of these strains contained carbapenemase genes. Of the 18 ertapenem-resistant strains, 17 expressed the efflux pump, and outer membrane protein expression was reduced or absent in 4 strains. Whole-genome sequencing revealed the presence of mutations that introduced premature ramR codons stop in 14 strains (77.78%). When a functional copy of ramR was restored in the 14 strains, the minimum inhibitory concentration of ertapenem decreased, inhibition of efflux pumps was not detected, and the expression of outer membrane protein OmpK35 was either increased or was restored. These findings reveal the existence of ertapenem-resistant K. pneumoniae exhibiting no clonal transmission between strains. Mutations in ramR were demonstrated to cause efflux pump inhibition and over-expression of outer membrane protein OmpK35 in some strains, which is implicated in ertapenem resistance only in K. pneumoniae.

The Role of C-reactive Protein Estimation in Determining the Duration of Antibiotic Therapy in Neonatal Sepsis

INTRODUCTION

Septicemia is globally considered the most important cause of neonatal morbidity and fatality. Serum C-Reactive Protein (CRP) is an acute phase reactant, which is brought out in response to the inflammatory reaction. It is prophesied to drop down speedily after the coherent weeding out of microbial incitation due to the short half-life of CRP. CRP levels reflect the individual's association between microbial infection and defensive mechanisms.  Methods: This hospital-based cross-sectional study included 150 admitted patients with suspected sepsis in the Department of Pediatrics, Rajendra Institute Medical Sciences (RIMS), Ranchi, India, over a study period of one year (2020 to 2021). CRP was estimated on the day of admission and repeated after 72 hours, on the fifth day, and on the seventh day for serial values of CRP, and the findings were compared by making three groups. Further, the research participants were designated to three different groups according to the CRP estimation levels.

RESULTS

Out of the 150 assumed neonatal septicemia patients, antibiotics were paused in 42 neonates (28%) within 72 hours. In group 2, 8% of neonates' antibiotics were stopped in five days, and a total of 102 neonates (68%) could be discharged on the seventh day of antibiotic therapy as their CRPs became negative on the third day and seventh day consecutively, along with negative blood culture reports. In group 3, antibiotics of 48 neonates (32%) were continued beyond seven days.

CONCLUSION

CRP has a skyscraping specificity and negative predictive values (NPV); thus, by estimating serial CRPs, the antibiotic therapy duration can be determined, which further helps determine the period of hospitalization.

Epidemiology and clinical characteristics of infection/colonization due to carbapenemase-producing Enterobacterales in neonatal patients

Background

The aim of this study was to elucidate the epidemiological features of carbapenemase-producing Enterobacterales (CPE) in the pediatric and neonatal patients, to describe clinical characteristics of neonatal patients with CPE infections, and to assess risk factors for neonatal rectal colonization with CPE.

Results

A total of 439 carbapenem-resistant Enterobacterales (CRE) isolates recovered from 367 infant patients were characterised, including 397 isolates of Klebsiella pneumoniae (KP) and 42 isolates of Escherichia coli (EC). Carbapenemase gene blaNDM-1 was the most commonly detected, accounting for 86.56% (n = 380), followed by blaKPC-2 (9.11%, 40) and blaIMP-4 (4.33%, 19). MLST analysis showed 17 different STs detected within CPKP isolates, with ST20, ST2068, ST36 and ST17 being the most frequently isolated types. Eleven STs were identified within CPEC isolates, with ST325 being the dominant types. Eight isolates of NDM-1 producing KP, belonging to ST23, were identified as having hypervirulent traits. The main infections caused by CPE were pneumonia (n = 90) and sepsis (n = 16). All infected patients received monotherapy, with meropenem and ciprofloxacin being the most commonly used antibiotics. All pneumonia patients were cured or improved after treatment. Of the 16 patients with sepsis, 9 were cured or improved, 3 died, and 4 abandoned treatment without any clinical improvement. The rectal prevalences of CPE in the 0–3 days old (DO), the 4–28 DO, and the 29 DO-1 year old groups were decreased from 15.31%, 27.37% and 14.29% in the first stool screening period to 11.78%, 19.59% and 4.07% in the second stool screening period, respectively. Multivariate analysis showed that cesarean section, acidosis, respiration failure, gastric lavage and enema were independent risk factors for rectal colonization in the 0–3 DO group, whereas cesarean section, cephalosporins, gastric lavage and residence in rural area were independently associated with rectal colonization in the 4–28 DO group. The implementation of a series of evidence-based control measures eventually contained the CPE transmission.

Conclusions

Continued vigilance, epidemiological studies, and multimodal infection prevention strategies are urgently needed due to frequent importations.

Hematological Abnormalities in Culture Positive Neonatal Sepsis

Background

In neonatal sepsis, anemia, leukocytosis, thrombocytopenia, and a shortened coagulation time are the most common hematologic abnormalities. However, there is inadequate information regarding the hematological abnormalities in neonatal sepsis. Thus, we aimed to determine the magnitude of hematological abnormalities in neonatal sepsis.

Methods

This is a cross-sectional study that included 143 neonates with culture proven sepsis aged 1–28 days from September 2020 to November 2021 at the University of Gondar Specialized Referral Hospital. The sociodemographic data was collected using a pre-tested structured questionnaire, and the clinical and laboratory data was collected using a data collection sheet. A total of 2 mL of venous blood was taken using a vacutainer collection device for the complete blood count (CBC) and blood culture analysis. A univariate and multivariate logistic regression model was used to investigate factors associated with hematological abnormalities in neonatal sepsis. Statistical significance was declared when a p-value was less than 0.05.

Results

The prevalence of anemia, thrombocytopenia, and leucopenia in neonatal sepsis was 49% (95% CI: 40.89–57.06), 44.7% (95% CI: 36.8–52.9), and 26.6% (95% CI: 22.01–29.40), respectively. On the other hand, leukocytosis and thrombocytosis were found in 7.7% (95% CI: 4.35–13.25) and 11.9% (95% CI: 7.56–18.21), respectively. Being female (AOR: 3.3; 95% CI: 1.20–3.82) and being aged less than 7 days (AOR: 2.44; 95% CI: 1.6–6.9) were found to be significant predictors of anemia.

Conclusion

The magnitude of anemia, leucopenia, and thrombocytopenia is high in neonatal sepsis. Furthermore, being female and being younger than 7 days were risk factors for anemia. Thus, the diagnosis and treatment of anemia, leucopenia, and thrombocytopenia prevents further complications in neonatal sepsis.

COVID-19 Clinical Profiles and Fatality Rates in Hospitalized Patients Reveal Case Aggravation and Selective Co-Infection by Limited Gram-Negative Bacteria

Bacterial co-infections may aggravate COVID-19 disease, and therefore being cognizant of other pathogens is imperative. We studied the types, frequency, antibiogram, case fatality rates (CFR), and clinical profiles of co-infecting-pathogens in 301 COVID-19 patients. Co-infection was 36% (n = 109), while CFR was 31.2% compared to 9.9% in non-co-infected patients (z-value = 3.1). Four bacterial species dominated, namely, multidrug-resistant Klebsiella pneumoniae (37%, n = 48), extremely drug-resistant Acinetobacter baumannii (26%, n = 34), multidrug-resistant Eschericia. coli (18.6%, n = 24), and extremely drug-resistant Pseudomonas aeruginosa (8.5%, n = 11), in addition to other bacterial species (9.3%, n = 12). Increased co-infection of K. pneumoniae and A. baumannii was associated with increased death rates of 29% (n = 14) and 32% (n = 11), respectively. Klebsiella pneumoniae was equally frequent in respiratory and urinary tract infections (UTI), while E. coli mostly caused UTI (67%), and A. baumannii and P. aeruginosa dominated respiratory infections (38% and 45%, respectively). Co-infections correlated with advance in age: seniors ≥ 50 years (71%), young adults 21–49 years (25.6%), and children 0–20 years (3%). These findings have significant clinical implications in the successful COVID-19 therapies, particularly in geriatric management. Future studies would reveal insights into the potential selective mechanism(s) of Gram-negative bacterial co-infection in COVID-19 patients.

Early-Onset Neonatal Sepsis in Low- and Middle-Income Countries: Current Challenges and Future Opportunities

Neonatal sepsis is defined as a systemic infection within the first 28 days of life, with early-onset sepsis (EOS) occurring within the first 72h, although the definition of EOS varies in literature. Whilst the global incidence has dramatically reduced over the last decade, neonatal sepsis remains an important cause of neonatal mortality, highest in low- and middle-income countries (LMICs). Symptoms at the onset of neonatal sepsis can be subtle, and therefore EOS is often difficult to diagnose from clinical presentation and laboratory testing and blood cultures are not always conclusive or accessible, especially in resource limited countries. Although the World Health Organisation (WHO) currently advocates a ß-lactam, and gentamicin for first line treatment, availability and cost influence the empirical antibiotic therapy administered. Antibiotic treatment of neonatal sepsis in LMICs is highly variable, partially caused by factors such as cost of antibiotics (and who pays for them) and access to certain antibiotics. Antimicrobial resistance (AMR) has increased considerably over the past decade and this review discusses current microbiology data available in the context of the diagnosis, and treatment for EOS. Importantly, this review highlights a large variability in data availability, methodology, availability of diagnostics, and aetiology of sepsis pathogens.

Two Phenotypes of Klebsiella pneumoniae ST147 Outbreak from Neonatal Sepsis with a Slight Increase in Virulence

Purpose

Severe infection has been the leading causes of neonatal death, especially the emergency of multidrug-resistant bacteria such as carbapenem-resistant Enterobacteriaceae. This study aimed to investigate the outbreak of carbapenem-resistant Klebsiella pneumoniae (CR-KP) in neonatal wards and to explore the possible pathogenesis of Klebsiella pneumoniae.

Materials and Methods

CR-KP were collected from neonatal ward of Chongqing Health Center for Women and Children between 2017 and 2019. Broth microdilution method was used to evaluate the antimicrobial activities in vitro, at the same time, the virulence of the strain was evaluated by in vitro and in vivo experiments. At last, prokaryotic chain specific transcriptome sequencing was conducted to explore the possible pathogenesis of CR-KP.

Results

In this study, a total of 14 carbapenem-resistant-Klebsiella pneumoniae (CR-KP) strains were isolated from Chongqing Health Center for Women and Children, among which all CR-KP isolates were identified as NDM-1-producers. Molecular epidemiological studies revealed ST147 being the most common sequence type (ST). Moreover, we first found two phenotypes of K. pneumoniae with different virulence from the same specimen. Type I, which was a white and sticky colony had a slight increase in virulence with higher biofilm formation, serum resistance and virulence than Type II with gray colony. Compared with the Type II, 10 pathways were obviously changed in Type I especially amino acid metabolism, such as arginine and proline metabolism.

Conclusion

Our findings revealed a new potential threat of NDM-1-positive CR-KP with higher virulence in neonatal ICU ward. We found two phenotypes of K. pneumoniae with different virulent, which may be due to the difference expression of arginine and proline metabolism.