Clinical characteristics and outcomes of carbapenem-resistant Enterobacterales bacteremia in pediatric patients

Pharmacokinetic/Pharmacodynamic Analysis of Extended/Two-Step Infusion Ceftazidime/Avibactam in Children With Gram-Negative Bacterial Infections

PURPOSE

To simulate the pharmacokinetic/pharmacodynamic (PK/PD) exposure of ceftazidime/avibactam (CZA) in children with gram-negative bacterial infections, and explore the appropriateness of the CZA standard dosing regimen (STD), further optimize the dosing regimen by extended/two-step infusion.

METHODS

Monte Carlo simulations were performed to calculate the probability of target attainment (PTA) and cumulative fraction of response (CFR) of CZA with varying weight in two age groups (≥6-12 and ≥12-18 years old, respectively), utilizing PK parameters and PD data (from the EUCAST as well as the published data on US children). The simulated dosing regimens included STD and extended/two-step infusion.

FINDINGS

When the PK/PD target for ceftazidime was set at 50% of time that free drug concentrations remain above the minimum inhibitory concentration of the pathogen during the dosing interval (50% fT > MIC), the CZA STD achieved PTAs of ≥90% at susceptibility breakpoint (MIC = 8 mg/L) for children in weighed 15-30 kg (≥6-12years old) and 35-45 kg (≥12-18 years old). However, when the PK/PD target for ceftazidime was set at 100% fT > MIC, none could achieve PTAs of ≥90%. The CFR results showed that the STD couldn't provide CFRs ≥90% in all children, but extended infusion or two-step infusion could achieve the target CFRs in all children based on the MIC distribution of US children, and improve the CFRs based on EUCAST's MIC distribution. Compared with extended infusion, two-step infusion could reduce total infusion time in partial patients.

IMPLICATIONS

The current STD of CZA may not adequately meet the therapeutic requirements in children, thus it is recommended to optimize the dosing regimen by extended/two-step infusion or increasing the daily dose, guided by therapeutic drug monitoring.

Bacteremia in the Gulf Cooperation Council Region: A Review of the Literature 2013-2023

Bloodstream infections (BSIs) are amongst the leading healthcare-associated infections (HCAIs), and their comprehensive evaluation and management are of global and regional importance. This narrative review examines and reports data on BSIs from the Gulf Cooperation Council (GCC) region covering the period between 2013 and 2023. The reviewed literature demonstrated that BSIs were frequently associated with critical care settings such as the Intensive Care Unit (ICU) and were often associated with invasive lines and devices [such as central-line associated BSI (CLABSI)]. Fever was the main presenting symptom, while diabetes mellitus and hypertension were the common associated comorbidities. High mortality rates were reported for BSIs, particularly when caused by multidrug-resistant (MDR) Gram-negative pathogens. There was a wide range of antimicrobial resistance rates reported across the region; however, carbapenem-resistance rates exceeding 30% were reported for Pseudomonas aeruginosa, Acinetobacter baumannii and Klebsiella pneumoniae. Few publications included molecular mechanisms of carbapenem resistance; however, when mechanisms were reported they were dominated by OXA-48. In conclusion, the lack of structured surveillance programs and networks to monitor microbiological phenotypic and genotypic patterns as well as clinical outcomes across the region means there is paucity of uniform data on BSIs across the GCC region. To bridge this gap, we recommend timely surveillance programs for the monitoring of resistance and outcomes.

Clinical outcomes of carbapenem-resistant gram-negative bacterial bloodstream infection in patients with end-stage renal disease in intensive care units: a multicenter retrospective observational study

BACKGROUND

Carbapenem-resistant gram-negative bacteria (CRGNB) present a considerable global threat due to their challenging treatment and increased mortality rates, with bloodstream infection (BSI) having the highest mortality rate. Patients with end-stage renal disease (ESRD) undergoing renal replacement therapy (RRT) face an increased risk of BSI. Limited data are available regarding the prognosis and treatment outcomes of CRGNB-BSI in patients with ESRD in intensive care units (ICUs).

METHODS

This multi-center retrospective observational study included a total of 149 ICU patients with ESRD and CRGNB-BSI in Taiwan from January 2015 to December 2019. Clinical and microbiological outcomes were assessed, and multivariable regression analysis was used to evaluate the independent risk factors for day-28 mortality and the impact of antimicrobial therapy regimen on treatment outcomes.

RESULTS

Among the 149 patients, a total of 127 patients (85.2%) acquired BSI in the ICU, with catheter-related infections (47.7%) and pneumonia (32.2%) being the most common etiologies. Acinetobacter baumannii (49.0%) and Klebsiella pneumoniae (31.5%) were the most frequently isolated pathogens. The day-28 mortality rate from BSI onset was 52.3%, and in-hospital mortality was 73.2%, with survivors experiencing prolonged hospital stays. A higher Sequential Organ Failure Assessment (SOFA) score (adjusted hazards ratio [aHR], 1.25; 95% confidence interval [CI] 1.17-1.35) and shock status (aHR, 2.12; 95% CI 1.14-3.94) independently predicted day-28 mortality. Colistin-based therapy reduced day-28 mortality in patients with shock, a SOFA score of ≥ 13, and Acinetobacter baumannii-related BSI.

CONCLUSIONS

CRGNB-BSI led to high mortality in critically ill patients with ESRD. Day-28 mortality was independently predicted by a higher SOFA score and shock status. In patients with higher disease severity and Acinetobacter baumannii-related BSI, colistin-based therapy improved treatment outcomes.

Geographic differences in susceptibility profiles of potential non-class B carbapenemase-producing Enterobacterales isolates against ceftazidime-avibactam, meropenem-vaborbactam, colistin, amikacin, gentamicin, and tigecycline: Data from the Antimicrobial Testing Leadership and Surveillance, 2018-2022

To evaluate the susceptibility profiles of regional meropenem-resistant potential non-class B carbapenemase-producing Enterobacterales (CPE) isolates (without confirmation by phenotypic tests) against important antibiotics, we extracted data from the 2018-2022 Antimicrobial Testing Leadership and Surveillance. This data included susceptibility information of meropenem-resistant potential non-class B CPE isolates against indicated antibiotics - amikacin, gentamicin, ceftazidime-avibactam, colistin, meropenem-vaborbactam, and tigecycline - from sepsis patients hospitalized in intensive care units across six major regions. Carbapenemase-encoding genes of the tested CPE isolates, determined by multiplex PCR and Sanger sequencing, were also analyzed. Susceptibility breakpoints recommended by Clinical and Laboratory Standards Institute 2024 and US FDA criteria (for tigecycline only) against Enterobacterales were employed. A total of 1500 potential non-class B CPE isolates (89% of which were Klebsiella pneumoniae) were tested globally. Resistance rates to amikacin and gentamicin against the evaluated isolates were statistically higher in Africa/the Middle East, Europe, and India compared to other regions. A similar pattern was observed in the susceptibility of these potential CPE isolates to ceftazidime-avibactam and meropenem-vaborbactam. High colistin resistance rates were noted in Asia, Latin America, and Europe (29%-35%). Furthermore, the proportions of potential CPE isolates carrying genes encoding blaOXA variants were notably higher among the tested CPE isolates in India, Europe, and Africa/the Middle East regions (99.2%, 53.3%, and 96.7%, respectively) compared to other regions. Trends in resistance to important antibiotics among potential non-class B CPE isolates warrant close monitoring.

Carbapenem-Resistant Enterobacteriaceae Bacteremia in Pediatric Patients in Latin America and the Caribbean: A Systematic Review and Meta-Analysis

Background: Data on the health impact of carbapenem-resistant Enterobacteriaceae bloodstream infections (CRE-BSIs) in pediatric populations from Latin America and the Caribbean (LAC) are limited. This systematic review aims to examine the demographic, clinical, and microbiological aspects and resource utilization of this infection in children from this region. Methods: This systematic review investigates the impact of CRE-BSIs in pediatric populations across LAC. Following the Cochrane methodology and PRISMA/MOOSE guidelines, we conducted an extensive search of different databases, including MEDLINE/PubMed, LILACS (SciELO), CENTRAL, CINAHL, Embase (Ovid), the Cochrane Library, and the World Health Organization (WHO) database, and relevant websites for published articles between January 2012 and September 2024. The review included studies on hospitalized patients under 19 years of age with CRE-BSIs. Results: Fourteen studies involving 189 patients were analyzed. Most cases were reported from Brazil, Argentina, Colombia, and Paraguay. The median age of the patients was 35 months. Key risk factors included immunocompromised status, invasive procedures, carbapenem use, and colonization. The infections were predominantly hospital-acquired, with Klebsiella pneumoniae and Serratia spp. being the most common pathogens. KPC and NDM were the primary resistance mechanisms. Most patients received combination antimicrobial therapy for a median of 17 days. An alarmingly high mortality rate at 34% was found. Conclusions: Our findings highlight that CRE-BSIs pose a significant threat to children with underlying conditions in LAC, leading to substantial morbidity and mortality. Implementing robust antimicrobial stewardship programs and effective infection control measures are crucial to curbing the spread of CRE-BSIs in the region. This review underscores the need for targeted interventions and further research to address this critical public health concern in pediatric populations across LAC.

The Effect of Gastrointestinal Mucositis Care Training Given to Pediatric Leukemic Patients and Caregivers on Mucosal Barrier Injury

BACKGROUND

Management of chemotherapy-induced mucosal barrier damage and oral/anal mucositis in leukemia is challenging.

OBJECTIVE

The aim of this study was to investigate the effect of mucositis care training given to children receiving leukemia treatment and their caregivers on caregiver knowledge and skills, the development of gastrointestinal mucositis in children, the mean oral mucositis area in children, and the mucosal barrier injury laboratory-confirmed bloodstream infection in the clinic.

METHODS

A stepped-wedge, quasi-experimental, unpaired control group design was used. The participants in the control group were given routine training, and the intervention group members were given mucositis care training in accordance with the guideline recommendations.

RESULTS

No significant difference was found between groups in developing anal mucositis, but a significant difference in developing oral mucositis was documented, with the mean mucositis area of children being 8.36 ± 3.97 cm2 in the control group and 4.66 ± 2.90 cm2 in the intervention group. The mucosal barrier injury laboratory-confirmed bloodstream infection ratio was 4 per 1000 catheter days in the control group and 3 per 1000 catheter days in the intervention group.

CONCLUSION

Mucositis care training had a significant positive effect on caregivers' knowledge and skills, the development of oral mucositis, and the mean oral mucositis area in children. However, the training had no effect on the development of anal mucositis or the infection rate in the clinic.

IMPLICATIONS FOR PRACTICE

Nurses might increase the knowledge and skill levels of caregivers with training on mucositis care, prevent the development of mucositis, and reduce the mean mucositis area. Training might also contribute to the reduction in the infection rate of the clinic.

Comparison of ERIC carbapenem-resistant Enterobacteriaceae test, BD Phoenix CPO detect panel, and NG-test CARBA 5 for the detection of main carbapenemase types of carbapenem-resistant Enterobacterales

BACKGROUND

This study aimed to assess the performance of three commercial panels, the ERIC Carbapenem-Resistant Enterobacteriaceae Test (ERIC CRE test), the NG-Test CARBA 5 (NG CARBA 5), and the BD Phoenix CPO Detect Panel (CPO panel), for the detection of main types of carbapenemases among carbapenem-resistant Enterobacterales (CRE).

METHODS

We collected 502 isolates of carbapenem-resistant Enterobacterales (CRE) demonstrating intermediate or resistant profiles to at least one carbapenem antibiotic (ertapenem, imipenem, meropenem, or doripenem). Carbapenemase genes and their specific types were identified through multiplex PCR and sequencing methods. Subsequently, the ERIC CRE test, CPO panel, and NG CARBA 5 assay were conducted on these isolates, and the results were compared with those obtained from multiplex PCR.

RESULTS

The results indicated that the ERIC CRE test exhibited an overall sensitivity and specificity of 98.1% and 93.6%, respectively, which were comparable to 99.1% and 90.6% for the NG CARBA 5. However, the CPO panel demonstrated a sensitivity of only 56.2% in identifying Ambler classes, exhibiting the poorest sensitivity for class A. Moreover, while the ERIC CRE test outperformed the NG CARBA 5 in identifying multi-gene isolates with multiple carbapenemase-encoding genes, the CPO panel failed to accurately classify these isolates.

CONCLUSIONS

Our findings support the utilization of the ERIC CRE test as one of the methods for detecting carbapenemases in clinical laboratories. Nonetheless, further optimization is imperative for the CPO panel to enhance its accuracy in determining carbapenemase classification and address limitations in detecting multi-gene isolates.

Epidemiology and antimicrobial susceptibility profiles of Enterobacterales causing bloodstream infections before and during COVID-19 pandemic: Results of the Study for Monitoring Antimicrobial Resistance Trends (SMART) in Taiwan, 2018-2021

BACKGROUND

The coronavirus disease 2019 (COVID-19) pandemic has contributed to the spread of antimicrobial resistance, including carbapenem-resistant Enterobacterales.

METHODS

This study utilized data from the Study for Monitoring Antimicrobial Resistance Trends (SMART) surveillance program in Taiwan. Enterobacterales from patients with bloodstream infections (BSIs) were collected and subjected to antimicrobial susceptibility testing and β-lactamase gene detection using a multiplex PCR assay. Statistical analysis was conducted to compare susceptibility rates and resistance genes between time periods before (2018-2019) and during the COVID-19 pandemic (2020-2021).

RESULTS

A total of 1231 Enterobacterales isolates were collected, predominantly Escherichia coli (55.6%) and Klebsiella pneumoniae (29.2%). The proportion of nosocomial BSIs increased during the COVID-19 pandemic (55.5% vs. 61.7%, p < 0.05). Overall, susceptibility rates for most antimicrobial agents decreased, with Enterobacterales from nosocomial BSIs showing significantly lower susceptibility rates than those from community-acquired BSIs. Among 123 Enterobacterales isolates that underwent molecular resistance mechanism detection, ESBL, AmpC β-lactamase, and carbapenemase genes were detected in 43.1%, 48.8% and 16.3% of the tested isolates, respectively. The prevalence of carbapenemase genes among carbapenem-resistant Enterobacterales increased during the pandemic, although the difference was not statistically significant. Two novel β-lactamase inhibitor combinations, imipenem-relebactam and meropenem-vaborbactam, preserved good efficacy against Enterobacterales. However, imipenem-relebactam showed lower in vitro activity against imipenem-non-susceptible Enterobacterales than that of meropenem-vaborbactam.

CONCLUSIONS

The COVID-19 pandemic appears to be associated with a general decrease in antimicrobial susceptibility rates among Enterobacterales causing BSIs in Taiwan. Continuous surveillance is crucial to monitor antimicrobial resistance during the pandemic and in the future.

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.

A Review of Carbapenem Resistance in Enterobacterales and Its Detection Techniques

Infectious disease outbreaks have caused thousands of deaths and hospitalizations, along with severe negative global economic impacts. Among these, infections caused by antimicrobial-resistant microorganisms are a major growing concern. The misuse and overuse of antimicrobials have resulted in the emergence of antimicrobial resistance (AMR) worldwide. Carbapenem-resistant Enterobacterales (CRE) are among the bacteria that need urgent attention globally. The emergence and spread of carbapenem-resistant bacteria are mainly due to the rapid dissemination of genes that encode carbapenemases through horizontal gene transfer (HGT). The rapid dissemination enables the development of host colonization and infection cases in humans who do not use the antibiotic (carbapenem) or those who are hospitalized but interacting with environments and hosts colonized with carbapenemase-producing (CP) bacteria. There are continuing efforts to characterize and differentiate carbapenem-resistant bacteria from susceptible bacteria to allow for the appropriate diagnosis, treatment, prevention, and control of infections. This review presents an overview of the factors that cause the emergence of AMR, particularly CRE, where they have been reported, and then, it outlines carbapenemases and how they are disseminated through humans, the environment, and food systems. Then, current and emerging techniques for the detection and surveillance of AMR, primarily CRE, and gaps in detection technologies are presented. This review can assist in developing prevention and control measures to minimize the spread of carbapenem resistance in the human ecosystem, including hospitals, food supply chains, and water treatment facilities. Furthermore, the development of rapid and affordable detection techniques is helpful in controlling the negative impact of infections caused by AMR/CRE. Since delays in diagnostics and appropriate antibiotic treatment for such infections lead to increased mortality rates and hospital costs, it is, therefore, imperative that rapid tests be a priority.