Intestinal Colonization of Preterm Neonates with Carbapenem Resistant Enterobacteria at Hospital Discharge

Clinical characteristics and mortality risk factors of premature infants with carbapenem-resistant Klebsiella pneumoniae bloodstream infection

Due to the resistance of carbapenem-resistant Klebsiella pneumoniae (CRKP) to most antibiotics, CRKP treatment is challenging, which results a high mortality rate. CRKP infection poses a significant challenge for infection management and treatment, especially among neonates and premature infants. Therefore, it is important to understand the clinical characteristics of CRKP bloodstream infection (BSI) in premature infants and identify the related risk factors for death. This study aims to explore and analyze the clinical characteristics and risk factors affecting mortality of BSI caused by CRKP in premature infants. A retrospective study was conducted in a Children's Hospital in Henan to analyze clinical data of premature infants with CRKP BSI admitted from January 2015 to December 2022. Univariate and multivariate logistic regression models were utilized to investigate risk factors affecting mortality. Receiver operating characteristic curves were employed to evaluate the predictive value of different indicators on mortality, and differences in area under the curve (AUC) were compared using Stata 17 SE. A total of 96 premature infants with CRKP BSI were enrolled, including 70 patients in the survival group and 26 in the death group. At the onset of infection, 69 (71.9%) patients exhibited persistent tachycardia (heart rate > 180 beats/min), 61 (63.5%) had fever, and 59 (61.4%) experienced apnea episodes. Concurrent meningitis (OR 9.588, 95% CI 1.401-57.613, P = 0.021), concurrent necrotizing enterocolitis (NEC) (OR 7.881, 95% CI 1.672-73.842, P = 0.032), and the maximum vasoactive-inotropic score (VIS) value within 48 h of onset (OR 1.467, 95% CI 1.021-1.782, P = 0.001) were identified as independent risk factors for mortality. The univariate analysis showed that ceftazidime-avibactam (CAZ/AVI) treatment and appropriate early antimicrobial treatment were significantly associated with survival (P < 0.05). The combined predictive AUC for mortality in premature infants with CRKP BSI using the maximum VIS value ≥ 52.5 points within 48 h of onset, concurrent NEC, and purulent meningitis was 0.931 (95% CI 0.856-1.000) with a sensitivity of 92% and specificity of 85.7%. CRKP BSI was a significant mortality risk in premature infants. It is crucial to administer proper antimicrobial therapy in order to increase survival rates of the patients. CAZ/AVI has the potential to improve outcomes in this particular population; however, further research is required to evaluate the effectiveness of specific treatment in premature infants.

Epidemiological and molecular characteristics of carbapenem-resistant Klebsiella pneumoniae from pediatric patients in Henan, China

PURPOSE

Carbapenem-resistant Klebsiella pneumoniae (CRKP) is an emerging global threat, whereas its epidemiological characteristics in children are rarely reported. This study aims to analyze clinical and epidemiological characteristics of CRKP from children in Henan, China.

METHODS

CRKP strains were isolated from pediatric patients, and the antimicrobial susceptibility of CRKP was determined using broth microdilution methods. The epidemiological characteristics of CRKP, including specimen sources, clinical data, carbapenemase types, virulence factors, MLST and PBRT typing were analyzed.

RESULTS

In total, 108 CRKP isolates were isolated from specimens including sputum, blood and urine, mainly from preterm pediatric department and internal medical intensive care unit (ICU). Newborns and staying in the ICU were risk factors for crude mortality. 107 isolates exhibited a multi-drug resistant (MDR) phenotype, and one isolate was extensively drug-resistant (XDR). Bacterial susceptibility to colistin, tigecycline and trimethoprim/sulfamethoxazole was 98.10%, 78.50% and 91.43%, respectively. Carbapenemase blaKPC (86.11%) was predominant, followed by blaNDM (5.56%) and blaIMP (2.78%). Two strains co-harbored blaKPC-blaNDM, one had blaKPC-blaIMP, whereas three isolates did not carry any of the analyzed carbapenemase genes. All strains possessed fimH, and 98% of the isolates possessed mrkD. Hypervirulent factors rmpA2 and iucA showed high positive rates (71.30% and 49.07%), with 48.15% of strains containing both genes. MLST analysis identified nine distinct sequence types (STs), with ST11 (82.41%) being the most common, followed by ST2154 (4.63%) and ST307 (3.70%). PBRT analysis revealed IncFII (85.19%) as the most prevalent plasmid.

CONCLUSION

In summary, this study reported the epidemiological features of CRKP in pediatric patients in Henan, China, highlighting the high prevalence of multi-drug-resistant and hypervirulent strains, and underscoring the significance of continuous surveillance.

Neonatal Colonization With Antibiotic-Resistant Pathogens in Low- and Middle-Income Countries: A Systematic Review and Meta-Analysis

Importance

In low- and middle-income countries (LMICs), neonatal bacterial infections are mainly caused by Enterobacterales species and Staphylococcus aureus, which are also the leading causes of mortality directly attributable to antimicrobial resistance. As bacterial colonization often precedes infection, better knowledge of colonization is crucial to prevent antibiotic-resistant neonatal sepsis.

Objective

To synthesize current evidence on the prevalence of and factors associated with colonization with third-generation cephalosporin-resistant Enterobacterales (3GCRE), carbapenem-resistant Enterobacterales (CRE), and methicillin-resistant S aureus (MRSA) during the first 3 months of life in LMICs.

Data Sources

PubMed, Scopus, Web of Science, and the World Health Organization Global Index Medicus were searched for articles published from January 1, 2000, through July 29, 2024.

Study Selection

Included studies were conducted in LMICs and reported prevalence rates or factors associated with colonization with 3GCRE, CRE, or MRSA in neonates and infants up to 3 months of age. Outbreak reports were excluded.

Data Extraction and Synthesis

Data extraction and risk-of-bias assessment using a Joanna Briggs Institute tool were performed by 2 independent reviewers. Pooled prevalence for each pathogen was computed using a random-effects model. Reporting followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guideline.

Main Outcomes and Measures

Prevalence of and factors associated with 3GCRE, CRE, and MRSA colonization.

Results

Of the 3147 articles identified in the search, 67 studies (51 for 3GCRE and CRE and 16 for MRSA) including 17 152 individuals were eligible. The pooled prevalence of 3GCRE colonization was 30.2% (95% CI, 21.4%-40.7%; τ2 = 1.48; I2 = 95.1%), varying from 18.2% (95% CI, 10.8%-29.1%) in nonhospitalized individuals to 48.2% (95% CI, 36.4%-60.2%) in hospitalized individuals. The prevalence of CRE colonization was 2.6% (95% CI, 0.7%-8.8%; τ2 = 7.79; I2 = 95.6%), while it was 2.7% (95% CI, 1.0%-6.7%; τ2 = 2.58; I2 = 93.5%) for MRSA. Increased risk of colonization with 3GCRE was associated with hospital birth (odds ratio [OR], 1.87; 95% CI, 1.33-2.64), neonatal antibiotic use (OR, 2.96; 95% CI, 1.43-6.11), and prolonged rupture of membranes (OR, 3.86; 95% CI, 2.19-6.84).

Conclusions and Relevance

In this systematic review and meta-analysis of antibiotic-resistant pathogen carriage in individuals aged 0 to 3 months, the pooled prevalence was substantial despite a limited exposure period. Although high heterogeneity between studies limited extrapolation of results, the findings highlight the need for further investigation to identify transmission routes and to design targeted and effective preventive measures.

Feeding cessation and antibiotics improve clinical symptoms and alleviate gut and systemic inflammation in preterm pigs sensitive to necrotizing enterocolitis

Necrotizing enterocolitis (NEC) is a microbiota- and feeding-related gut inflammatory disease in preterm infants. The standard of care (SOC) treatment for suspected NEC is antibiotic treatment and reduced enteral feeding, but how SOC treatment mitigates NEC remains unclear. We explored whether SOC treatment alone or combined with an anti-inflammatory protein (inter-alpha inhibitor protein, IAIP) supplementation improves outcomes in a preterm piglet model of formula-induced NEC. Seventy-one cesarean-delivered preterm piglets were initially fed formula, developing NEC symptoms by day 3, and then randomized into CON (continued feeding) or SOC groups (feeding cessation and antibiotics), each with or without human IAIP (2×2 factorial design). By day 5, IAIP treatment did not significantly influence outcomes, whereas SOC treatment effectively reduced NEC lesions, diarrhea, and bloody stools. Notably, SOC treatment improved gut morphology and function, dampened gut inflammatory responses, altered the colonic microbiota composition, and modulated systemic immune responses. Plasma proteomic analysis revealed the effects of SOC treatment on organ development and systemic inflammatory responses. Collectively, these findings suggest that SOC treatment significantly prevents NEC progression in preterm piglets via effects on gut structure, function, and microbiota, as well as systemic immune and inflammatory responses. Timely feeding cessation and antibiotics are critical factors in preventing NEC progression in preterm infants, while the benefits of additional human IAIP treatment remain to be established.

Carbapenem-Resistant Enterobacterales in the Western Balkans: Addressing Gaps in European AMR Surveillance Map

In the context of global efforts to combat antimicrobial resistance (AMR), the importance of comprehensive AMR data is more crucial than ever. AMR surveillance networks, such as the European Antimicrobial Resistance Surveillance Network (EARS-Net) and the Central Asian and European Surveillance of Antimicrobial Resistance (CAESAR), support member states in obtaining high-quality AMR data. Nevertheless, data gaps persist in some countries, including those in the Western Balkans (WBs), a region with high AMR rates. This review analyzed existing research on carbapenem-resistant Enterobacterales (CRE) to better understand the AMR landscape in the WB countries. The most prevalent CRE was Klebsiella pneumoniae, followed by Escherichia coli, Enterobacter cloacae, and Proteus mirabilis, with sporadic cases of Morganella morganii, Providencia spp., Klebsiella oxytoca, and Citrobacter sedlakii. Carbapenemase production was identified as the most common mechanism of carbapenem resistance, but other resistance mechanisms were not investigated. An increasing trend in carbapenem resistance has been observed over the last decade, alongside a shift in carbapenemase epidemiology from the NDM type in 2013-2014 to the OXA-48 type in recent years. Few studies have applied whole-genome sequencing for CRE analysis, which has demonstrated the spread of resistance determinants across different niches and over time, emphasizing the importance of molecular-based research. The overall low number of studies in the WB countries can be attributed to limited resources, highlighting the need for enhanced support in education, training, technology, and equipment to improve data collection and evaluation.

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.

Prevalence of intestinal colonization and nosocomial infection with carbapenem-resistant Enterobacteriales in children: a retrospective study

Objective

We investigated the epidemiological surveillance of the intestinal colonization and nosocomial infection of carbapenem-resistant Enterobacteriales (CRE) isolates from inpatients, which can provide the basis for developing effective prevention.

Methods

A total of 96 CRE strains were collected from 1,487 fecal samples of hospitalized children between January 2016 and June 2017, which were defined as the "CRE colonization" group. In total, 70 CRE clinical isolates were also randomly selected for the comparison analysis and defined as the "CRE infection" group. The antimicrobial susceptibility of all strains was determined by the microdilution broth method. Polymerase chain reaction (PCR) was used to analyze carbapenemase genes, plasmid typing, and integrons. Multilocus sequence typing was further used to determine clonal relatedness.

Results

In the "CRE colonization" group, Klebsiella pneumoniae was mostly detected with a rate of 42.7% (41/96), followed by Escherichia coli (34.4%, 33/96) and Enterobacter cloacae (15.6%, 15/96). The ST11 KPC-2 producer, ST8 NDM-5 producer, and ST45 NDM-1 producer were commonly present in carbapenem-resistant K. pneumoniae (CRKPN), carbapenem-resistant E. coli (CRECO), and carbapenem-resistant E. cloacae (CRECL) isolates, respectively. In the "CRE infection" group, 70% (49/70) of strains were K. pneumoniae, with 21.4% E. cloacae (15/70) and 5.7% E. coli (4/70). The ST15 OXA-232 producer and ST48 NDM-5 producer were frequently observed in CRKPN isolates, while the majority of NDM-1-producing CRECL isolates were assigned as ST45. Phylogenetic analysis showed that partial CRE isolates from intestinal colonization and nosocomial infection were closely related, especially for ST11 KPC-2-producing CRKPN and ST45 NDM-1-producing CRECL. Furthermore, plasmid typing demonstrated that IncF and IncFIB were the most prevalent plasmids in KPC-2 producers, while IncX3/IncX2 and ColE were widely spread in NDM producer and OXA-232 producer, respectively. Then, class 1 integron intergrase intI1 was positive in 74.0% (71/96) of the "CRE colonization" group and 52.9% (37/70) of the "CRE infection" group.

Conclusion

This study revealed that CRE strains from intestinal colonization and nosocomial infection showed a partial correlation in the prevalence of CRE, especially for ST11 KPC-2-producing CRKPN and ST45 NDM-1-producing CRECL. Therefore, before admission, long-term active screening of rectal colonization of CRE isolates should be emphasized.

Use of Newer and Repurposed Antibiotics against Gram-Negative Bacteria in Neonates

Antimicrobial resistance has become a significant public health problem globally with multidrug resistant Gram negative (MDR-GN) bacteria being the main representatives. The emergence of these pathogens in neonatal settings threatens the well-being of the vulnerable neonatal population given the dearth of safe and effective therapeutic options. Evidence from studies mainly in adults is now available for several novel antimicrobial compounds, such as new β-lactam/β-lactamase inhibitors (e.g., ceftazidime-avibactam, meropenem-vaborbactam, imipenem/cilastatin-relebactam), although old antibiotics such as colistin, tigecycline, and fosfomycin are also encompassed in the fight against MDR-GN infections that remain challenging. Data in the neonatal population are scarce, with few clinical trials enrolling neonates for the evaluation of the efficacy, safety, and dosing of new antibiotics, while the majority of old antibiotics are used off-label. In this article we review data about some novel and old antibiotics that are active against MDR-GN bacteria causing sepsis and are of interest to be used in the neonatal population.