Whole Genome Sequencing of Extended-Spectrum Beta-Lactamase-Producing Klebsiella pneumoniae Isolated from Neonatal Bloodstream Infections at a Neonatal Care Unit, Algeria

Aims: Neonatal bloodstream infections (BSIs) are an important cause of mortality among neonates. Besides, extended-spectrum beta-lactamase-producing Klebsiella pneumoniae (ESBL-Kp) is one of the most frequent pathogens causing neonatal BSIs. This study aimed to characterize ESBL-Kp strains recovered from neonatal BSI and to investigate risk factors associated with ESBL-Kp BSI at the neonatal care unit of Elmeki Hospital, Bejaia, Algeria. Methodology: After isolation, identification, and antibiotic susceptibility testing, the ESBL-Kp strains were characterized by whole genome sequencing. The genomes were then analyzed using bioinformatic tools to determine the resistome, virulome, and phylogenetic relatedness. Results: From September 2019 to May 2020, 27 (8.2%) out of 328 neonates were infected by ESBL-Kp strains. These strains displayed a multidrug-resistant phenotype, and on further investigation, were found to carry an array of antibiotic resistance genes. All ESBL-Kp strains harbored the bla_CTX-M-15 gene. Using in silico multilocus sequence typing analysis, six sequence types (STs) were detected with ST268 being the most frequent (56%, n = 15) indicating a local outbreak, confirmed by single nucleotide polymorphism analysis. The yersiniabactin and colibactin gene clusters were identified in six and two ESBL-Kp strains, respectively. Conclusion: This study showed a high prevalence of CTX-M-15-producing K. pneumoniae strains coharboring different antibiotic resistance mechanisms from neonatal BSIs in Algeria. Screening of health care personnel and mothers for ESBL carriage before delivery, isolation of carriers, barrier precautions, antimicrobial usage, and control of hygiene are needed to prevent the dissemination of these pathogens.

Clinical and immunological aspects of microRNAs in neonatal sepsis

Neonatal sepsis constitutes a highly relevant public health challenge and is the most common cause of infant morbidity and mortality worldwide. Recent studies have demonstrated that during infection epigenetic changes may occur leading to reprogramming of gene expression. Post-transcriptional regulation by short non-coding RNAs (e.g., microRNAs) have recently acquired special relevance because of their role in the regulation of the pathophysiology of sepsis and their potential clinical use as biomarkers. ~22-nucleotide of microRNAs are not only involved in regulating multiple relevant cellular and molecular functions, such as immune cell function and inflammatory response, but have also been proposed as good candidates as biomarkers in sepsis. Nevertheless, establishing clinical practice guidelines based on microRNA patterns as biomarkers for diagnosis and prognosis in neonatal sepsis has yet to be achieved. Given their differential expression across tissues in neonates, the release of specific microRNAs to blood and their expression pattern can differ compared to sepsis in adult patients. Further in-depth research is necessary to fully understand the biological relevance of microRNAs and assess their potential use in clinical settings. This review provides a general overview of microRNAs, their structure, function and biogenesis before exploring their potential clinical interest as diagnostic and prognostic biomarkers of neonatal sepsis. An important part of the review is focused on immune and inflammatory aspects of selected microRNAs that may become biomarkers for clinical use and therapeutic intervention.

miRNA-23b as a biomarker of culture-positive neonatal sepsis

BACKGROUND

Neonatal sepsis remains an important cause of morbidity and mortality. The ability to quickly and accurately diagnose neonatal sepsis based on clinical assessments and laboratory blood tests remains difficult, where haemoculture is the gold standard for detecting bacterial sepsis in blood culture. It is also very difficult to study because neonatal samples are lacking.

METHODS

Forty-eight newborns suspected of sepsis admitted to the Neonatology Department of the Mother-Child Specialized Hospital of Tlemcen. From each newborn, a minimum of 1-2 ml of blood was drawn by standard sterile procedures for blood culture. The miRNA-23b level in haemoculture was evaluated by RT-qPCR.

RESULTS

miR-23b levels increased in premature and full-term newborns in early onset sepsis (p < 0.001 and p < 0.005 respectively), but lowered in late onset sepsis in full-term neonates (p < 0.05) compared to the respective negative controls. miR-23b levels also increased in late sepsis in the negative versus early sepsis negative controls (p < 0.05). miR-23b levels significantly lowered in the newborns who died from both sepsis types (p < 0.0001 and p < 0.05 respectively). In early sepsis, miR-23b and death strongly and negatively correlated (correlation coefficient = - 0.96, p = 0.0019). In late sepsis, miRNA-23b and number of survivors (correlation coefficient = 0.70, p = 0.506) positively correlated.

CONCLUSIONS

Lowering miR-23b levels is an important factor that favours sepsis development, which would confirm their vital protective role, and strongly suggest that they act as a good marker in molecular diagnosis and patient monitoring.

Length of stay, cost, and mortality of healthcare-acquired bloodstream infections in children and neonates: A systematic review and meta-analysis

OBJECTIVE

To estimate the attributable mortality, length of stay (LOS), and healthcare cost of pediatric and neonatal healthcare-acquired bloodstream infections (HA-BSIs).

DESIGN

A systematic review and meta-analysis.

METHODS

A systematic search (January 2000-September 2018) was conducted in PubMed, Cochrane, and CINAHL databases. Reference lists of selected articles were screened to identify additional studies. Case-control or cohort studies were eligible for inclusion when full text was available in English and data for at least 1 of the following criteria were provided: attributable or excess LOS, healthcare cost, or mortality rate due to HA-BSI. Study quality was evaluated using the Critical Appraisal Skills Programme Tool (CASP). Study selection and quality assessment were conducted by 2 independent researchers, and a third researcher was consulted to resolve any disagreements. Fixed- or random-effect models, as appropriate, were used to synthesize data. Heterogeneity and publication bias were evaluated.

RESULTS

In total, 21 studies were included in the systematic review and 13 studies were included in the meta-analysis. Attributable mean LOS ranged between 4 and 27.8 days; healthcare cost ranged between $1,642.16 and $160,804 (2019 USD) per patient with HA-BSI; and mortality rate ranged between 1.43% and 24%. The pooled mean attributable hospital LOS was 16.91 days (95% confidence interval [CI], 13.70-20.11) and the pooled attributable mortality rate was 8% (95% CI, 6-9). A meta-analysis was not conducted for cost due to lack of eligible studies.

CONCLUSIONS

Pediatric HA-BSIs have a significant impact on mortality, LOS, and healthcare cost, further highlighting the need for implementation of HA-BSI prevention strategies.

Systematic Review on the Acute Cost-of-illness of Sepsis and Meningitis in Neonates and Infants

BACKGROUND

Sepsis and meningitis in neonates and infants are a source of substantial morbidity, mortality and economic loss. The objective of this review is to estimate the acute costs associated with treating sepsis, meningitis and meningococcal septicemia, in neonates and infants, worldwide.

METHODS

The electronic databases Medline, Embase and EconLit were searched and exported on November 24, 2018. Studies that reported an average hospitalization cost for confirmed cases of sepsis, meningitis or meningococcal septicemia were eligible for our review. Descriptive data were extracted and reported costs were inflated and converted. A narrative synthesis of the costs was conducted.

RESULTS

Our review identified 20 studies reporting costs of sepsis, meningitis and/or meningococcal septicemia. Costs ranged from $55 to $129,632 for sepsis and from $222 to $33,635 for meningitis (in 2017 US dollars). One study estimated the cost of meningococcal septicemia to be $56,286. All reported costs were estimated from the perspective of the healthcare provider or payer. Most studies were from the United States, which also had the highest costs. Only a few studies were identified for low- and middle-income countries, which reported lower costs than high-income countries for both sepsis and meningitis.

CONCLUSIONS

Sepsis and meningitis in neonates and infants are associated with substantial costs to the healthcare system and showed a marked difference across global income groups. However, more research is needed to inform costs in low- and middle-income settings and to understand the economic costs borne by families and wider society.

Healthcare associated infections in Paediatric Intensive Care Unit of a tertiary care hospital in India: Hospital stay & extra costs

BACKGROUND & OBJECTIVES

Healthcare associated infections (HAIs) increase the length of stay in the hospital and consequently costs as reported from studies done in developed countries. The current study was undertaken to evaluate the impact of HAIs on length of stay and costs of health care in children admitted to Paediatric Intensive Care Unit (PICU) of a tertiary care hospital in north India.

METHODS

This prospective study was done in the seven bedded PICU of a large multi-specialty tertiary care hospital in New Delhi, India. A total of 20 children with HAI (cases) and 35 children without HAI (controls), admitted to the PICU during the study period (January 2012 to June 2012), were matched for gender, age, and average severity of illness score. Each patient's length of stay was obtained prospectively. Costs of healthcare were estimated according to traditional and time driven activity based costing methods approach.

RESULTS

The median extra length of PICU stay for children with HAI (cases), compared with children with no HAI (controls), was seven days (IQR 3-16). The mean total costs of patients with and without HAI were ' 2,04,787 (US$ 3,413) and ' 56,587 (US$ 943), respectively and the mean difference in the total cost between cases and controls was ' 1,48,200 (95% CI 55,716 to 2,40,685, p<0.01).

INTERPRETATION & CONCLUSIONS

This study highlights the effect of HAI on costs for PICU patients, especially costs due to prolongation of hospital stay, and suggests the need to develop effective strategies for prevention of HAI to reduce costs of health care.

Infectious Complications and Morbidities After Neonatal Bloodstream Infections: An Observational Cohort Study

Few data are available on the clinical characteristics of complications and morbidities after neonatal bloodstream infections (BSIs), understood as any newly infectious focus or organ dysfunction directly related to BSIs but not occur concurrently. However, these bloodstream-associated infectious complications (BSICs) contribute significantly to increased hospital stay, cost, and final mortality. We performed an observational cohort study of unselected neonatal intensive care unit (NICU) patients based on records in a large clinical database. All neonates hospitalized in our NICU with BSI between 2006 and 2013 were reviewed, and those who developed BSICs were analyzed to identify the clinical characteristics and outcomes. Multivariate logistic regression was used to identify independent risk factors for BSICs. Of 975 episodes of neonatal BSI, 101 (10.4%) BSICs occurred in 93 neonates with a median interval of 3 days (range, 0-17 days) after onset of BSI and included newly infectious focuses in 40 episodes (39.6%), major organ dysfunctions after septic shock in 36 episodes (35.6%), and neurological complications after meningitis or septic shock in 34 episodes (33.7%). All patients with BSICs encountered various morbidities, which subsequently resulted in in-hospital death in 30 (32.3%) neonates, critical discharge in 4 (4.3%), and persistent sequelae in 17 (18.3%). After multivariate logistic regression analysis, independent risk factors for BSICs included initial inappropriate antibiotics (odds ratio [OR], 5.54; 95% confidence interval [CI], 3.40-9.01), BSI with septic shock (OR, 5.75; 95% CI, 3.51-9.40), and BSI concurrent with meningitis (OR, 9.20; 95% CI, 4.33-19.56). It is worth noting that a percentage of neonates with BSI encountered subsequent sequelae or died of infections complications, which were significantly associated with initial inappropriate antibiotic therapy, septic shock, and the occurrence of meningitis. Further investigation is warranted to decrease the occurrence of BSICs due to their significant contribution toward final mortality.

Update on infection control challenges in special pediatric populations

PURPOSE OF REVIEW

Compared with adults, neonatal and pediatric populations are especially vulnerable patients who have specific diagnostic and therapeutic differences; therefore, the standard infection control practices designed for adults are sometimes not effective or need modifications to work. This review focuses on the recent literature addressing the challenges and successes in preventing healthcare-associated infections (HAIs) in children.

RECENT FINDINGS

Improving the implementation of pediatric versions of preventive bundles focusing on proper catheter insertion and maintenance, mainly as a part of a larger multimodal strategy, is effective in reducing the central-line-associated bloodstream infections in neonatal and pediatric populations including oncology patients. Appropriate feeding, antimicrobial stewardship, and infection control measures should be combined in reducing necrotizing enterocolitis in preterm neonates. Implementing a multimodal bundle strategy adapted for pediatric population is successful in preventing ventilator-associated pneumonia. Appropriate use of antimicrobial prophylaxis remains the cornerstone for preventing surgical-site infections irrespective of age, with few additional effective adjuvant preventive practices in specific pediatric patients.

SUMMARY

Several evidence-based practices are effective in reducing the incidence and the impact of HAIs in children; however, proper implementation remains a challenge. Additionally, several adult preventive practices are still unestablished in children and need further thorough examination.

Repositioning of Memantine as a Potential Novel Therapeutic Agent against Meningitic E. coli-Induced Pathogenicities through Disease-Associated Alpha7 Cholinergic Pathway and RNA Sequencing-Based Transcriptome Analysis of Host Inflammatory Responses

Neonatal sepsis and meningitis (NSM) remains a leading cause worldwide of mortality and morbidity in newborn infants despite the availability of antibiotics over the last several decades. E. coli is the most common gram-negative pathogen causing NSM. Our previous studies show that α7 nicotinic receptor (α7 nAChR), an essential regulator of inflammation, plays a detrimental role in the host defense against NSM. Despite notable successes, there still exists an unmet need for new effective therapeutic approaches to treat this disease. Using the in vitro/in vivo models of the blood-brain barrier (BBB) and RNA-seq, we undertook a drug repositioning study to identify unknown antimicrobial activities for known drugs. We have demonstrated for the first time that memantine (MEM), a FDA-approved drug for treatment of Alzheimer’s disease, could very efficiently block E. coli-caused bacteremia and meningitis in a mouse model of NSM in a manner dependent on α7 nAChR. MEM was able to synergistically enhance the antibacterial activity of ampicillin in HBMEC infected with E. coli K1 (E44) and in neonatal mice with E44-caused bacteremia and meningitis. Differential gene expression analysis of RNA-Seq data from mouse BMEC infected with E. coli K1 showed that several E44-increased inflammatory factors, including IL33, IL18rap, MMP10 and Irs1, were significantly reduced by MEM compared to the infected cells without drug treatment. MEM could also significantly up-regulate anti-inflammatory factors, including Tnfaip3, CISH, Ptgds and Zfp36. Most interestingly, these factors may positively and negatively contribute to regulation of NF-κB, which is a hallmark feature of bacterial meningitis. Furthermore, we have demonstrated that circulating BMEC (cBMEC) are the potential novel biomarkers for NSM. MEM could significantly reduce E44-increased blood level of cBMEC in mice. Taken together, our data suggest that memantine can efficiently block host inflammatory responses to bacterial infection through modulation of both inflammatory and anti-inflammatory pathways.

Bloodstream infections: epidemiology and resistance

Bloodstream infections in the neonatal intensive care unit (NICU) are associated with many adverse outcomes in infants, including increased length of stay and cost, poor neurodevelopmental outcomes, and death. Attention to the insertion and maintenance of central lines, along with careful review of when the catheters can be safely discontinued, can minimize central-line-associated bloodstream infections rates. Good antibiotic stewardship can further decrease the incidence of bloodstream infections, minimize the emergence of drug-resistant organisms or Candida as pathogens in the NICU, and safeguard the use of currently available antibiotics for future infants.

Neurological complications after neonatal bacteremia: the clinical characteristics, risk factors, and outcomes

Background

Neonates with bacteremia are at risk of neurologic complications. Relevant information warrants further elucidation.

Study Design

This was a retrospective cohort study of neonates with bacteremia-related neurologic complications (BNCs) in a tertiary-level neonatal intensive care unit (NICU). A systemic chart review was performed conducted to identify clinical characteristics and outcomes. A cohort of related conditions was constructed as the control group. Logistic regression analysis was used to identify independent risk factors for BNC.

Results

Of 1037 bacteremia episodes, 36 (3.5%) had BNCs. Twenty-four cases of BNCs were related to meningitis, five were presumed meningitis, and seven occurred after septic shock. The most common causative pathogens were Group B streptococcus (41.7%) and E. coli (16.7%). The major BNCs consisted of seizures (28), hydrocephalus (20), encephalomalacia (11), cerebral infarction (7), subdural empyema (6), ventriculitis (8), and abscess (4). Eight (22.8%) neonates died and six (16.7%) were discharged in critical condition when the family withdrew life-sustaining treatment. Among the 22 survivors, eight had neurologic sequelae upon discharge. After multivariate logistic regression analysis, neonates with meningitis caused by Group B streptococcus (adjusted odds ratio [OR]: 8.90, 95% confidence interval [CI]: 2.20–36.08; p = 0.002) and combined meningitis and septic shock (OR, 5.94; 95% CI: 1.53–23.15; p = 0.010) were independently associated with BNCs.

Conclusions

Neonates with bacteremia-related neurologic complications are associated with adverse outcomes or sequelae. Better strategies aimed at early detection and reducing the emergence of neurologic complications and aggressive treatment of Group B streptococcus sepsis are needed in neonates with meningitis and septic shock.

Risk factors and outcomes for multidrug-resistant Gram-negative bacteremia in the NICU

OBJECTIVES

To assess the risk factors antibiotic therapy and outcomes of multidrug-resistant (MDR) Gram-negative bacilli (GNB) bacteremia in NICU patients.

METHODS

Episodes of MDR GNB bacteremia were compared with a non-MDR GNB bacteremia group in an 8-year cohort study.

RESULTS

Of 1106 bacteremias, 393 (35.5%) were caused by GNB. Seventy (18.6%) were caused by an MDR strain. The most frequent mechanism of resistance was extended-spectrum β-lactamase production (67.1%), mainly by Klebsiella pneumoniae (59.6%). Previous antibiotic exposure to third-generation cephalosporin (odds ratio [OR]: 5.97; 95% confidence interval [CI]: 2.37-15.08; P < .001) and carbapenem (OR: 3.60; 95% CI: 1.26-10.29; P = .017) and underlying renal disease (OR: 7.08; 95% CI: 1.74-28.83; P = .006) were identified as independent risk factors for MDR GNB acquisition. Patients with MDR GNB bacteremia more likely received inadequate initial antibiotic therapy (72.9% vs 7.8%; P < .001) had higher rates of infectious complication (21.4% vs 10.5%; P = .011) and overall case fatality +rate (28.6% vs 10.5%; P < .001). Independent risk factors for overall mortality were presence of infectious complications after bacteremia (OR: 3.16; 95% CI: 1.41-7.08; P = .005) and underlying secondary pulmonary hypertension with or without cor pulmonale (OR: 6.19; 95% CI: 1.88-20.31; P = .003).

CONCLUSIONS

MDR GNB accounted for 18.6% of all neonatal GNB bacteremia in the NICU, especially in those with previous broad-spectrum antibiotic therapy and underlying renal disease. The most frequent mechanism of resistance was extended-spectrum β-lactamase (ESBL) production. Neonates with MDR GNB were more likely to develop infectious complications, which were independently associated with a higher overall case-fatality rate.

Incidence, clinical characteristics and risk factors for adverse outcome in neonates with late-onset sepsis

BACKGROUND

Late-onset sepsis (LOS) is a common complication in the neonatal intensive care unit. We aimed to describe the epidemiology, clinical characteristics and risk factors for adverse outcome in neonates with LOS.

METHODS

We conducted a cohort study of all neonates with LOS at the neonatal intensive care unit of a Tertiary Taiwan Medical Center from January 2004 through December 2011 and used multivariate logistic regression to identify risk factors for final adverse outcome.

RESULTS

Among 5010 neonates over 253,644 neonate-days, 713 (14.2%) experienced a total of 942 episodes of LOS (incidence rate, 3.71 episodes per 1000 neonate-days). Although the rates of LOS were inversely proportional to birth weight and gestational age, the incidence rates were comparable among extremely preterm, late preterm and full term neonates. Fungemia was found to have significantly higher rate of infectious complication (30.8%), persistent bloodstream infection (19.2%) and sepsis attributable mortality (23.1%). The overall mortality rate was 12.6% (90/713), and sepsis attributable mortality rate was 7.2% (68/942 episodes). Independent predictors of in-hospital mortality were Pseudomonas LOS (adjusted odds ratio [OR], 14.31; 95% confidence interval [CI]: 3.87-53.0), fungemia (OR, 5.69; 95% CI: 2.48-13.01), presence of congenital anomalies (OR, 4.12; 95% CI: 1.60-10.60), neuromuscular comorbidities (OR, 3.34; 95% CI: 1.66-6.73) and secondary pulmonary hypertension with/without cor pulmonale (OR, 23.48; 95% CI: 5.96-92.49).

CONCLUSIONS

LOS predisposes hospitalized neonates to increased risk of mortality or morbidity, especially caused by Pseudomonas aeruginosa or Candida spp. More aggressive treatment strategy is worth consideration in neonates with presumed LOS, particularly those with certain underlying chronic conditions.