Neonatal sepsis: an old problem with new insights

Neonatal Sepsis

Purpose of Review

Neonatal sepsis is a diagnosis made in infants less than 28 days of life and consists of a clinical syndrome that may include systemic signs of infection, circulatory shock, and multisystem organ failure.

Recent Findings

Commonly involved bacteria include Staphylococcus aureus and Escherichia coli. Risk factors include central venous catheter use and prolonged hospitalization. Neonates are at significant risk of delayed recognition of sepsis until more ominous clinical findings and vital sign abnormalities develop. Blood culture remains the gold standard for diagnosis.

Summary

Neonatal sepsis remains an important diagnosis requiring a high index of suspicion. Immediate treatment with antibiotics is imperative.

The liver as a nursery for leukocytes

Leukocytes are a large population of cells spread within most tissues in the body. These cells may be either sessile (called as resident cells) or circulating leukocytes, which travel long journeys inside the vessels during their lifespan. Although production and maturation of these leukocytes in adults primarily occur in the bone marrow, it is well known that this process-called hematopoiesis-started in the embryonic life in different sites, including the yolk sac, placenta, and the liver. In this review, we will discuss how the liver acts as a pivotal site for leukocyte maturation during the embryo phase, and also how the most frequent liver-resident immune cell populations-namely Kupffer cells, dendritic cells, and lymphocytes-play a vital role in both tolerance and inflammatory responses to antigens from food, microbiota, and pathogens.

Validation of Risk Stratification Criteria to Identify Febrile Neonates at Low Risk of Serious Bacterial Infection

Our objective was to evaluate the accuracy of risk stratification criteria for febrile neonates in the emergency department. This was a retrospective study of febrile neonates ≤56 days of age. Patients were low risk for serious bacterial infection (SBI) if all test results were within normal ranges. Three hundred thirty-eight patients were enrolled with a mean age of 32 (±14) days, and 78 (23%) had SBI: 26 (8%) with bacteremia, 48 (14%) with urinary tract infection, 3 (1%) with meningitis, and 11 (3%) with pneumonia. Risk stratification criteria identified 47 (14%) as low risk, 2 of whom had SBI (both with Group B Streptococcus bacteremia). The sensitivity was 97.4% (95% confidence interval = 91.0% to 99.7%), and the negative predictive value was 95.7% (95% confidence interval = 84.8% to 98.9%). The risk stratification criteria have high sensitivity and high negative predictive value for identifying infants at low risk for SBI. Care must be taken to assure reliable follow-up.

Epidemiology of infections and antimicrobial use in Greek Neonatal Units

OBJECTIVE

To describe the epidemiology of neonatal infections and of antimicrobial use in Greek Neonatal Units (NNUs) in order to develop national, evidence-based guidelines on empiric antimicrobial use for neonatal sepsis in Greece.

DESIGN

Retrospective analysis of prospectively collected infection surveillance data from 2012 to 2015, together with a Point Prevalence Survey (PPS) on antimicrobial use and the collection of data on local empiric antimicrobial policies.

SETTING

16 NNUs in Greece participating in the neonIN infection surveillance network PATIENTS: Newborns in participating NNUs who had a positive blood, cerebrospinal fluid or urine culture and were treated with at least 5 days of antibiotics.

RESULTS

459 episodes were recorded in 418 infants. The overall incidence of infection was 50/1000 NNU-admissions. The majority of episodes were late-onset sepsis (LOS) (413, 90%). Coagulase-negative Staphylococci (80%) were the most common Gram-positive organisms causing LOS and Klebsiella spp (39%) the most common Gram-negative. Nearly half (45%) of the Klebsiella spp were resistant to at least one aminoglycoside. The PPS revealed that 196 of 484 (40%) neonates were on antimicrobials. The survey revealed wide variation in empiric antimicrobial policies for LOS.

CONCLUSIONS

This is the largest collection of data on the epidemiology of neonatal infections in Greece and on neonatal antimicrobial use. It provides the background for the development of national evidence-based guidelines. Continuous surveillance, the introduction of antimicrobial stewardship interventions and evidence-based guidelines are urgently required.

A sensitive scoring system for the longitudinal clinical evaluation and prediction of lethal disease outcomes in newborn mice

Neonatal animal models are increasingly employed in order to unravel age-specific disease mechanisms. Appropriate tools objectifying the clinical condition of murine neonates are lacking. In this study, we tested a scoring system specifically designed for newborn mice that relies on clinical observation and examination. Both, in a neonatal sepsis model and an endotoxic shock model, the scoring results strongly correlated with disease-induced death rates. Full as well as observation-restricted scoring, reliably predicted fatality and the remaining time until death. Clinical scores even proved as more sensitive biomarker than 6 traditionally used plasma cytokine levels in detecting sepsis at an early disease stage. In conclusion, we propose a simple scoring system that detects health impairments of newborn mice in a non-invasive longitudinal and highly sensitive manner. Its usage will help to meet animal welfare requirements and might improve the understanding of neonatal disease mechanisms.

Determinants and Outcome of Community-Acquired Late-Onset Neonatal Sepsis in Rural Bangladesh

Background. This study examined the sociodemographic as well as other determinants and outcome of community-acquired late-onset neonatal sepsis (LONS) in rural Bangladesh at Matlab. Methods. In this retrospective chart review, we used an unmatched case-control design (1:2 ratio) to evaluate the factors associated with LONS and their outcomes among babies admitted to the neonatal ward of Matlab Hospital of icddr,b, from January 2012 to December 2014. Neonates presenting with any of the clinical signs of serious bacterial infection during 3 to 28 days of life constituted the cases (LONS), and those without LONS constituted the controls. All the data were retrieved from the electronic databases of Matlab Hospital and Matlab Health and Demographic Surveillance System. Results. Among 1482 admitted neonates, 202 were cases and 404 were randomly selected controls. In babies with LONS, case fatality rate (1% vs 0%, P = .037), duration of inpatient stay (4 days vs 2 days, P < .001), and referral to higher center (9% vs 5%, P = .020) were higher. In an adjusted model, undernutrition (weight for length Z score < −2; odds ratio [OR] = 1.8, 95% confidence interval [CI] = 1.2-2.94), admission in winter season (OR = 1.62, 95% CI = 1.09-2.41), mother’s schooling <10 years (OR = 1.76, 95% CI = 1.09-2.85), primiparity (OR = 1.55, 95% CI = 1.05-2.29), home delivery (OR = 1.87, 95% CI = 1.07-3.26), and household food insecurity (OR = 2.78, 95% CI = 1.31-5.88) were found to be independently associated with LONS. Conclusion. LONS posed considerable socioeconomic burden to the rural community. Further studies are required to consolidate our findings.

Clinical features and antimicrobial susceptibility profiles of culture-proven neonatal sepsis in a tertiary children's hospital, 2013 to 2017

Neonatal sepsis (NS) remains a major cause of morbidity and mortality in neonates, but data on the etiology and antibiotic susceptibility patterns of pathogens are limited. The aim of this study was to analyze the clinical characteristics, risk factors, and the antibiotic susceptibility patterns of pathogenic microbes associated with NS at a tertiary children's hospital in Shanghai, China.Episodes of blood culture-proven sepsis in the neonatal intensive care unit (NICU) of Children's Hospital of Fudan University from January 2013 to August 2017 were retrospectively reviewed. Collected data included demographics, perinatal risk factors, clinical symptoms, laboratory values, microbiology results and their antimicrobial susceptibility. Data for early-onset neonatal sepsis (EONS) and late-onset neonatal sepsis (LONS) were compared.The 341 of 976 culture-positive cases were selected, including 161 EONS cases (47.21% of 341) and 180 LONS cases (52.79% of 341). 635 incomplete cases were excluded. There was significant difference in risk factors between the EONS group and LONS group including birth weight, gestational age, 1-minute Apgar score, respiratory support, and the use of peripherally insertion central catheter (PICC). Clinical symptoms such as fever, feeding intolerance, abdominal distension, and neonatal jaundice, and laboratory results such as hemoglobin and lymphocyte counts also showed between-group differences. Staphylococcus epidermidis (22.87%), Escherichia coli (9.68%), Alcaligenes xylosoxidans (9.38%) and Klebsiella pneumoniae (9.09%) remain the principal organisms responsible for neonatal sepsis. Most isolates of Gram-positive bacteria were sensitive to vancomycin, linezolid, minocycline and tigecycline, of which more than 90% were resistant to penicillin. Most isolates of Gram-negative bacteria were sensitive to amikacin and imipenem and resistant to ampicillin. Fungus was sensitive to antifungal agents. Better medical decisions, especially early detection and appropriate initial antimicrobial therapy can be made after understanding the different clinical features and pathogens of EONS and LONS.

Neonatal Vitamin D status and the risk of neonatal sepsis

Objective:

To evaluate the maternal and neonatal 25-hydroxyvitamin D [25(OH)D] levels and the effect of 25(OH)D levels on the development of neonatal sepsis.

Methods:

This prospective study was performed in the neonatal intensive care unit of Medicine Hospital/Biruni University between November 2017 and September 2018. Fifty one term infants with sepsis group and 56 term infants with control group were included in this study. Blood samples for whole blood count, CRP, Ca, P, ALP, 25(OH)D and culture were obtained from all neonates.

Results:

Mean vitamin D levels for the neonates and their mothers were found to be 12.4±8.5 ng/ml and 13±8.7 ng/ml, respectively. There was a significant correlation between maternal and newborn 25(OH)D levels (r=0.72, p<0.01). The number of the newborns with vitamin D deficiency was significantly higher in the sepsis group (n=31, 60.8%) than in the control group (n=30, 53.6%; p=0.00), corresponding to significantly lower levels of vitamin D in the sepsis group (11±5.5 ng/ml vs. 13.8±10.6 ng/ml; p=0.012). Similarly, maternal vitamin D levels was significantly lower in the sepsis group than in the control group (10.8±5.6 ng/ml vs. 14.9±10 ng/ml; p=0.001).

Conclusion:

Our findings suggest that there may be an association between vitamin D deficiency and neonatal sepsis

Systematic Review of the Effectiveness of the Neonatal Early-Onset Sepsis Calculator

Neonatal early-onset sepsis is a serious health concern for term and late preterm infants. Screening for early-onset sepsis is often challenging due to variation in practice, nonspecific laboratory markers, and clinical findings that mimic immaturity. This systematic review evaluates the evidence for the effectiveness of the Neonatal Early-Onset Sepsis Calculator (EOScalc) as a screening tool to appropriately identify neonatal early-onset sepsis and the ability to decrease unnecessary antibiotic use in late preterm and term infants. A comprehensive search of retrospective cohort and retrospective case-control studies was conducted using 5 databases. Studies were included if they evaluated the EOScalc within the defined parameters of use and excluded if they were not published. Six studies were identified and included from 2014 to 2017. Study comparisons varied on the basis of differing clinical practice and use of the EOScalc. Findings included in this review suggest that utilization of the EOScalc can reduce empiric antibiotic therapy, unnecessary laboratory testing, and separation of infants and mothers without increasing infant mortality.

Use of Mannose-Binding Lectin Gene Polymorphisms and the Serum MBL Level for the Early Detection of Neonatal Sepsis

Background  Mannose-binding lectin (MBL) is a component of innate immunity and is particularly important in neonates, in whom adaptive immunity has not yet completely developed. MBL deficiency and MBL2 gene polymorphisms are associated with an opsonization defect and have been associated with neonatal sepsis. Aim  The aim of our study was to assess serum MBL levels and genotype MBL2 genes to determine whether they can serve as markers for predicting neonatal sepsis in neonatal intensive care units. Patients and Methods  A case-control study was conducted with 114 neonates classified into two groups: the septic group included 64 neonates (41 preterm and 23 full-term infants), and the non-septic control group included 50 neonates (29 preterm and 21 full-term infants). Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis was used to genotype MBL2 gene exon 1 (rs1800450) and (rs1800451) SNPs. Enzyme-linked immunosorbent assay (ELISA) was used to measure MBL serum concentrations. Results  The polymorphic genotypes BB and AC at codons 54 and 57, respectively, showed higher frequencies than the wild-type genotype (AA) (14.1% versus 12.9% and 28.1% versus 19.4% respectively) in both groups, and this difference was greater in the septic group than in the non-septic group; however, the differences did not reach statistical significance. The B and C allele frequencies were also higher in the septic group than in the non-septic group, but the differences did not reach statistical significance ( p  = 0.282 and 0.394, respectively). The serum levels of MBL were significantly lower in the septic group than in the non-septic group ( p  = 0.028). Conclusion  This study found no association between MBL levels or MBL2 exon 1 genotypes or alleles and neonatal sepsis risk. Further studies with larger sample sizes are needed to determine the role of the MBL2 gene as a risk factor and early predictor of neonatal sepsis.

Epidemiology of UK neonatal infections: the neonIN infection surveillance network

OBJECTIVE

To describe the epidemiology of neonatal infection over the past decade in UK neonatal units.

DESIGN

Retrospective analysis of prospectively collected infection surveillance network data from 2005 to 2014.

SETTING

30 neonatal units in the UK.

PATIENTS

Newborns on participating neonatal units who had a positive blood, cerebrospinal fluid or urine culture and were treated with at least 5 days of appropriate antibiotics.

RESULTS

2171 episodes of neonatal infection in 1922 infants were recorded. The incidence of infection was 6.1/1000 live births and 48.8/1000 neonatal admissions (2.9 and 23.5 respectively if coagulase-negative staphylococci (CoNS) cultures excluded). The incidence of infection showed a statistically significant reduction over time with reductions in the rates of both early-onset sepsis (EOS) and late-onset sepsis (LOS).The majority of episodes (76%) represented LOS (diagnosed > 48 hours after birth), and infection was more common in premature (<37 weeks gestation) and low birth weight (<2500 g) neonates (84% and 81%, respectively). Commonly identified pathogens included group B streptococci (43%) and Escherichia coli (18%) for EOS, while E. coli (15%), Staphylococcus aureus (14%) and CoNS were prominent causes of LOS.

CONCLUSIONS

This paper describes the epidemiology of neonatal infection in the UK over the past decade. These data enable benchmarking of practice and inform areas of future research and guideline development. The results support the hypothesis that the introduction of infection prevention care bundles and antibiotic stewardship programmes in the UK has reduced the burden of LOS.

Vitamin D and associated perinatal-neonatal outcomes among extremely low-birth-weight infants

OBJECTIVE

To evaluate vitamin D inadequacy among extremely low-birth-weight (ELBW, <1000 g) infants and the association between circulating vitamin D concentrations and perinatal-neonatal outcomes.

STUDY DESIGN

Prospective cohort study of ELBW infants in the neonatal ICU. Blood was collected within the first 3 days after birth after obtaining informed consent. Circulating 25-hydroxyvitamin D concentrations (25(OH)D) were quantified using liquid chromatography-tandem mass spectroscopy and classified as vitamin D deficient, insufficient, or adequate ( < 20, 20-30, or > 30 ng/mL, respectively). Associations between 25(OH)D and perinatal-neonatal outcomes were determined by multivariable regression, adjusted for covariates that differ in the bivariate analysis.

RESULTS

Of the 60 ELBW infants enrolled, 13 (22%) were vitamin D deficient, 15 (25%) were insufficient, and 32 (53%) were adequate. 25(OH)D levels were positively associated with fetal growth restriction and prolonged rupture of the membranes.

CONCLUSIONS

Vitamin D inadequacy was frequent among ELBW infants. Circulating vitamin D concentrations were significantly associated with perinatal outcomes in this contemporary cohort.

Beyond sepsis: Staphylococcus epidermidis is an underestimated but significant contributor to neonatal morbidity

Staphylococcus epidermidis accounts for the majority of cases of neonatal sepsis. Moreover, it has been demonstrated to be associated with neonatal morbidities, such as bronchopulmonary dysplasia (BPD), white matter injury (WMI), necrotizing enterocolitis (NEC) and retinopathy of prematurity (ROP), which affect short-term and long-term neonatal outcome. Imbalanced inflammation has been considered to be a major underlying mechanism of each entity. Conventionally regarded as a harmless commensal on human skin, S. epidermidis has received less attention than its more virulent relative Staphylococcus aureus. Particularities of neonatal innate immunity and nosocomial environmental factors, however, may contribute to the emergence of S. epidermidis as a significant nosocomial pathogen. Neonatal host response to S. epidermidis sepsis has not been fully elucidated. Evidence is emerging regarding the implication of S. epidermidis sepsis in the pathogenesis of neonatal inflammatory diseases. This review focuses on the interplay among S. epidermidis, neonatal innate immunity and inflammation-driven organ injury.

Antimicrobial resistance in UK neonatal units: neonIN infection surveillance network

OBJECTIVE

To define the susceptibilities of the common causative pathogens of neonatal sepsis in the UK.

DESIGN

Retrospective analysis of the prospectively collected neonIN infection surveillance network data between 2005 and 2014.

SETTING

30 neonatal units in the UK.

PATIENTS

Newborns admitted to participating neonatal units who return a positive blood, cerebrospinal fluid or urine culture and are treated with at least 5 days of appropriate antibiotics.

RESULTS

1568 isolates with recorded antimicrobial data were collected including 328 early-onset sepsis (EOS) isolates and 1240 late-onset sepsis (LOS) isolates. The majority of EOS pathogens (>92%) were susceptible to the four empirical commonly used antimicrobial combinations (eg, 93% for benzylpenicillin/gentamicin), while LOS pathogens demonstrated higher levels of resistance (eg, 89% for flucloxacillin/gentamicin). Among infants<1500 g and <32 weeks gestation, an amoxicillin/gentamicin combination demonstrated a trend towards improved coverage of EOS isolates than benzylpenicillin/gentamicin (93% vs 86%, p=0.211).

CONCLUSIONS

This analysis provides insights into the patterns of antimicrobial resistance among UK neonatal pathogens. These data will inform areas of future research and can be used to update national evidence-based guidelines on antimicrobial usage.

Evaluate the diagnosis of neonatal sepsis by measuring interleukins: A systematic review

Neonatal sepsis is a dangerous and common disease among infants which is associated with high morbidity and mortality. Interleukins may be helpful for diagnosis of neonatal sepsis. Therefore, this study is conducted to investigate the role of interleukins in the diagnosis of neonatal sepsis. In this study, databases including PubMed, Cochrane Library, ISI and Google Scholar were searched up to 2016. Keywords were: Sepsis, neonatal, interleukins, prediction and diagnosis. Study inclusion criteria were: Articles about the relationship between the diagnosis of neonatal sepsis and interleukins; studies on babies; English and Persian articles and enough information from test results. Articles that had focused on adult sepsis or had used other markers except ILs or just their abstracts were available were excluded from the study. Of 100 searched studies, eventually, 16 articles were considered including 12 prospective studies, 3 cross-sectional studies and 1 retrospective study. IL6 has been studied more than other interleukins (50% of articles). ILs 6, 8 and 10 are among the initial markers of neonatal sepsis diagnosis. IL6 above 68 pg/ml had 85% sensitivity and 80% specificity, IL8 above 269.51 pg/ml had 80% sensitivity and 50% specificity, IL10 above 27 pg/ml had 60% sensitivity and 87% specificity and combined interleukins above 186.83 pg/ml had 75.63% sensitivity and 71.49% specificity in sepsis diagnosis. Interleukins can be helpful in the diagnosis of neonatal sepsis based on the results of this study. IL6 had the most sensitivity and IL10 had the most specificity for diagnosis of sepsis.

Children with Chronic Disease Bear the Highest Burden of Pediatric Sepsis

OBJECTIVE

To describe the contemporary epidemiology of pediatric sepsis in children with chronic disease, and the contribution of chronic diseases to mortality. We examined the incidence and hospital mortality of pediatric sepsis in a nationally representative sample and described the contribution of chronic diseases to hospital mortality.

STUDY DESIGN

We analyzed the 2013 Nationwide Readmissions Database using a retrospective cohort design. We included non-neonatal patients <19 years of age hospitalized with sepsis. We examined patient characteristics, the distribution of chronic disease, and the estimated national incidence, and described hospital mortality. We used mixed effects logistic regression to explore the association between chronic diseases and hospital mortality.

RESULTS

A total of 16 387 admissions, representing 14 243 unique patients, were for sepsis. The national incidence was 0.72 cases per 1000 per year (54 060 cases annually). Most (68.6%) had a chronic disease. The in-hospital mortality was 3.7% overall-0.7% for previously healthy patients and 5.1% for patients with chronic disease. In multivariable analysis, oncologic, hematologic, metabolic, neurologic, cardiac and renal disease, and solid organ transplantation were associated with increased in-hospital mortality.

CONCLUSIONS

More than 2 of 3 children admitted with sepsis have ≥1 chronic disease and these patients have a higher in-hospital mortality than previously healthy patients. The burden of sepsis in hospitalized children is greatest in pediatric patients with chronic disease.

Etiologic and Pathogenic Perinatal Factors for the Development of Intrauterine Infections in Newborns (Review)

For many decades, the world community’s efforts have been aimed at reducing the neonatal and infant mortality from intrauterine infections. In 1990, the United Nations and the World Health Organization set out the priority of decreasing children mortality by 2015 году. In spite of impressive success in newborn treatment, mortality due to sepsis decreases slowly; when survive, postnatal children develop central nervous system impairments of different level of severity. In the recent decade, new data have emerged concerning the methods of intrauterine infections prophylaxis, diagnosis, and treatment. The purpose of the review is to present data concerning specifics of pregnancy course when infections develop, contemporary diagnostic methods including studies of interleukins, placenta morphology, allelic genes, and to reflect the current approach to the treatment of intrauterine infections in newborns. 

Comparison between presepsin and procalcitonin in early diagnosis of neonatal sepsis

Background: Neonatal sepsis remains worldwide one of the leading causes of morbidity and mortality in both term and preterm infants. Lower mortality rates are related to timely diagnostic evaluation and prompt initiation of empiric antibiotic therapy. Blood culture, as gold standard examination for sepsis, has several limitations for early diagnosis, so that sepsis biomarkers could play an important role in this regard. This study was aimed to compare the value of the two biomarkers presepsin and procalcitonin in early diagnosis of neonatal sepsis. Methods: This was a prospective cross-sectional study performed in Saiful Anwar General Hospital Malang, Indonesia, in 51 neonates that fulfill the criteria of systemic inflammatory response syndrome (SIRS) with blood culture as diagnostic gold standard for sepsis. Results: At reviewer operating characteristic (ROC) curve analyses, using a presepsin cutoff of 706.5 pg/mL, the obtained area under the curve (AUCs) were sensitivity = 85.7%, specificity = 68.8%, positive predictive value = 85.7%, negative predictive value = 68.8%, positive likelihood ratio = 2.75, negative likelihood ratio = 0.21, and accuracy = 80.4%. On the other hand, with a procalcitonin cutoff value of 161.33 pg/mL the obtained AUCs showed: sensitivity = 68.6%, specificity = 62.5%, positive predictive value = 80%, negative predictive value = 47.6%, positive likelihood ratio = 1.83, the odds ratio negative = 0.5, and accuracy = 66.7%. Conclusions: In early diagnosis of neonatal sepsis, compared with procalcitonin, presepsin seems to provide better early diagnostic value with consequent possible faster therapeutical decision making and possible positive impact on outcome of neonates.

A novel model to study neonatal Escherichia coli sepsis and the effect of treatment on the human immune system using humanized mice

PROBLEM

Neonatal sepsis is a serious threat especially for preterm infants. As existing in vitro and in vivo models have limitations, we generated a novel neonatal sepsis model using humanized mice and tested the effect of Betamethasone and Indomethacin which are used in the clinic in case of premature birth.

METHOD OF STUDY

Humanized mice were infected with Escherichia coli (E. coli). Subsequently, the effect of the infection itself, and treatment with Betamethasone and Indomethacin on survival, recovery, bacterial burden, leukocyte populations, and cytokine production, was analyzed.

RESULTS

The human immune system in the animals responded with leukocyte trafficking to the site of infection and granulopoiesis in the bone marrow. Treatment with Indomethacin had no pronounced effect on the immune system or bacterial burden. Betamethasone induced a decline of splenocytes.

CONCLUSION

The human immune system in humanized mice responds to the infection, making them a suitable model to study neonatal E. coli sepsis and the immune response of the neonatal immune system. Treatment with Betamethasone could have potential negative long-term effects for the immune system of the child.

Thromboelastometry for diagnosis of neonatal sepsis-associated coagulopathy: an observational study

Our aim was to evaluate the potential role of standard extrinsically activated thromboelastometry (EXTEM) assay in the early detection of neonatal sepsis. We studied 91 hospitalized neonates categorized in two groups: group A included 35 neonates with confirmed sepsis, while group B included 56 neonates with suspected sepsis; 274 healthy neonates served as controls. Whenever sepsis was suspected, EXTEM assay was performed, Score for Neonatal Acute Physiology Perinatal Extension (SNAPPE) and Tοllner score were calculated, and clinical findings and laboratory results were recorded. Septic neonates had significantly prolonged clotting time (CT) and clot formation time (CFT), and reduced maximum clot firmness (MCF), compared to neonates with suspected sepsis (p values 0.001, 0.001, and 0.009, respectively) or healthy neonates (p values 0.001, 0.001, and 0.021, respectively). EXTEM parameters (CT, CFT, MCF) demonstrated a more intense hypocoagulable profile in septic neonates with hemorrhagic diathesis than those without (p values 0.021, 0.007, and 0.033, respectively). In septic neonates, CFT was correlated with platelet count, SNAPPE, Tollner score, and day of full enteral feeding (p values 0.01, 0.02, 0.05, and 0.03, respectively).

CONCLUSIONS

A ROTEM hypocoagulable profile at admission seems promising for the early detection of sepsis in neonates while the degree of hypocoagulation may be associated with sepsis severity. What is Known: • The early phase of septicemia might be difficult to be recognized in neonates. In adult septic patients, the diagnostic and prognostic role of thromboelastometry (ROTEM) have been extensively investigated. • Limited data are available on the role of ROTEM as an indicator of early neonatal sepsis. What is New: • ROTEM measurements indicate an early appearance of hypocoagulability in neonatal sepsis, while the degree of hypocoagulation might be associated with severity of sepsis. • ROTEM could be a useful tool in the early detection of sepsis in neonates.

C reactive protein in healthy term newborns during the first 48 hours of life

BACKGROUND

Early-onset neonatal sepsis (EOS) is a serious and potentially life-threatening disease in newborns. C reactive protein (CRP) is the most used laboratory biomarker for the detection of EOS. Little is known about normal reference values of CRP during the perinatal period as several factors are able to influence it.

OBJECTIVES

To identify an appropriate range of CRP values in healthy term newborns during the first 48 hours of life.

DESIGN

CRP determination was performed in 859 term newborns at 12, 24 and 48 hours of life. Mode of delivery, maternal vaginal culture results, intrapartum antimicrobial prophylaxis (IAP) and other perinatal variables were recorded.

RESULTS

CRP mean values were significantly higher at 48 hours (4.10 mg/L) than at both 24 (2.30 mg/L) and 12 hours of life (0.80 mg/L). CRP levels were affected by a number of perinatal proinflammatory variables. In particular, CRP mean values were significantly higher in babies born by vaginal delivery (3.80 mg/L) and emergency caesarean section (3.60 mg/L) than in babies born by elective caesarean section (2.10 mg/L). Completed course of IAP led to lower CRP mean values (2.90 mg/L) than IAP not completed (3.80 mg/L) or not performed (4.70 mg/L).

CONCLUSIONS

Postnatal age and mode of delivery significantly influence CRP values. Reliable reference values are crucial in order to obtain an adequate diagnostic accuracy.

Presepsin as a predictor of positive blood culture in suspected neonatal sepsis

BACKGROUND

Although the incidence of neonatal sepsis is decreasing, neonatal sepsis remains a severe life-threatening disease. No current biochemical marker can provide perfect diagnostic accuracy for neonatal sepsis. The aim of this study was therefore to evaluate the accuracy of presepsin (P-SEP) as a novel biomarker of bacterial infection for neonatal sepsis diagnosis.

METHODS

We prospectively studied newborns with sepsis (sepsis group; n = 13) during the first 30 days after birth and compared them with control preterm newborns (control group; n = 18). In addition, we evaluated term newborns with some clinical signs of early onset sepsis (non-sepsis term group; n = 35).

RESULTS

P-SEP in the sepsis group was significantly higher than in the control group (P < 0.001) The area under the curve for P-SEP was 0.868 (95%CI: 0.71-1.00). A P-SEP cut-off of 795 pg/mL was established, with 85% sensitivity and 89% specificity. The positive and negative predictive values were 85% and 89%, respectively. In the non-sepsis term group, P-SEP had better stability than white blood cells and C-reactive protein for 3 days after birth.

CONCLUSIONS

P-SEP can better discriminate between infections and non-infectious inflammatory conditions than the currently used biomarkers.

Sepsis-Induced Immunosuppression in Neonates

Neonates, especially those born preterm, are at increased risk of sepsis and adverse long-term effects associated with infection-related inflammation. Distinct neonatal immune responses and dysregulated inflammation are central to this unique susceptibility. The traditional separation of sepsis into an initial hyper-inflammatory response followed by hypo-inflammation is continually under review with new developments in this area of research. There is evidence to support the association of mortality in the early acute phase of sepsis with an overwhelming hyper-inflammatory immune response. Emerging evidence from adults suggests that hypo- and hyper-inflammation can occur during any phase of sepsis and that sepsis-immunosuppression is associated with increased mortality, morbidity, and risk to subsequent infection. In adults, sepsis-induced immunosuppression (SII) is characterised by alterations of innate and adaptive immune responses, including, but not limited to, a prominent bias toward anti-inflammatory cytokine secretion, diminished antigen presentation to T cells, and reduced activation and proliferation of T cells. It is unclear if sepsis-immunosuppression also plays a role in the adverse outcomes associated with neonatal sepsis. This review will focus on exploring if key characteristics associated with SII in adults are observed in neonates with sepsis.

Using newborn screening analytes to identify cases of neonatal sepsis

Neonatal sepsis is associated with high mortality and morbidity, yet challenges with available diagnostic approaches can lead to delays in therapy. Our study assessed whether newborn screening analytes could be utilized to identify associations with neonatal sepsis. We linked a newborn screening registry with health databases to identify cases of sepsis among infants born in Ontario from 2010-2015. Correlations between sepsis and screening analytes were examined within three gestational age groups (early preterm: <34 weeks; late preterm: 34-36 weeks; term: ≥37 weeks), using multivariable logistic regression models. We started with a model containing only clinical factors, then added groups of screening analytes. Among 793,128 infants, 4,794 were diagnosed with sepsis during the neonatal period. Clinical variables alone or in combination with hemoglobin values were not strongly predictive of neonatal sepsis among infants born at term or late preterm. However, model fit improved considerably after adding markers of thyroid and adrenal function, acyl-carnitines, and amino acids. Among infants born at early preterm gestation, neither clinical variables alone nor models incorporating screening analytes adequately predicted neonatal sepsis. The combination of clinical variables and newborn screening analytes may have utility in identifying term or late preterm infants at risk for neonatal sepsis.

Codevelopment of Microbiota and Innate Immunity and the Risk for Group B Streptococcal Disease

The pathogenesis of neonatal late-onset sepsis (LOD), which manifests between the third day and the third month of life, remains poorly understood. Group B Streptococcus (GBS) is the most important cause of LOD in infants without underlying diseases or prematurity and the third most frequent cause of meningitis in the Western world. On the other hand, GBS is a common intestinal colonizer in infants. Accordingly, despite its adaption to the human lower gastrointestinal tract, GBS has retained its potential virulence and its transition from a commensal to a dangerous pathogen is unpredictable in the individual. Several cellular innate immune mechanisms, in particular Toll-like receptors, the inflammasome and the cGAS pathway, are engaged by GBS effectors like nucleic acids. These are likely to impact on the GBS-specific host resistance. Given the long evolution of streptococci as a normal constituent of the human microbiota, the emergence of GBS as the dominant neonatal sepsis cause just about 50 years ago is remarkable. It appears that intensive usage of tetracycline starting in the 1940s has been a selection advantage for the currently dominant GBS clones with superior adhesive and invasive properties. The historical replacement of Group A by Group B streptococci as a leading neonatal pathogen and the higher frequency of other β-hemolytic streptococci in areas with low GBS prevalence suggests the existence of a confined streptococcal niche, where locally competing streptococcal species are subject to environmental and immunological selection pressure. Thus, it seems pivotal to resolve neonatal innate immunity at mucous surfaces and its impact on microbiome composition and quality, i.e., genetic heterogeneity and metabolism, at the microanatomical level. Then, designer pro- and prebiotics, such as attenuated strains of GBS, and oligonucleotide priming of mucosal immunity may unfold their potential and facilitate adaptation of potentially hazardous streptococci as part of a beneficial local microbiome, which is stabilized by mucocutaneous innate immunity.

Nurses' Early Recognition of Neonatal Sepsis

OBJECTIVE

To determine nurses' perceptions of the most common physiologic and behavioral indicators of neonatal sepsis.

DESIGN

Descriptive correlational study.

SETTING

A women's and children's hospital in an academic medical center in the southwestern United States.

PARTICIPANTS

Nurses (N = 181) who cared for neonates in the mother-infant and NICU settings.

METHODS

Participants completed an e-mail survey developed from the literature to ascertain their perceptions of which physiologic and behavioral indicators were most often associated with neonatal sepsis. Descriptive and inferential statistics were used to analyze the data.

RESULTS

Participants identified six signs and symptoms as indicators most often associated with sepsis: two were physiologic and four were behavioral. Recognition of these indicators was not related to level of nursing education but was associated with working in the NICU. Seventy-three percent of participants reported that they suspected that newborns were septic before evaluation and diagnosis of septicemia.

CONCLUSION

Nurses can identify the physiologic and behavioral indicators related to neonatal sepsis. Early recognition, expressed as their intuitive knowing, should be considered a valuable clinical tool. Understanding that different practice settings influence identification of signs and symptoms is important. Integration of this knowledge into formal care surveillance could potentially lower the threshold for early evaluation and treatment and thereby improve outcomes.

Effects of cord blood vitamin D levels on the risk of neonatal sepsis in premature infants

Purpose

Vitamin D plays a key role in immune function. Vitamin D deficiency may play a role in the pathogenesis of infections, and low levels of circulating vitamin D are strongly associated with infectious diseases. In this study, we aimed to evaluate the effects of low vitamin D levels in cord blood on neonatal sepsis in preterm infants.

Methods

One hundred seventeen premature infants with gestational age of <37 weeks were enrolled. In the present study, severe vitamin D deficiency (group 1) was defined as a 25-hydroxyvitamin D (25(OH)D) concentration <5 ng/mL; vitamin D insufficiency (group 2), 25(OH)D concentration ≥5 ng/mL and <15 ng/mL; and vitamin D sufficiency (group 3), 25(OH)D concentration ≥15 ng/mL.

Results

Sixty-three percent of the infants had deficient levels of cord blood vitamin D (group 1), 24% had insufficient levels (group 2), and 13% were found to have sufficient levels (group 3). The rate of neonatal sepsis was higher in group 2 than in groups 1 and 3.

Conclusion

There was no significant relationship between the cord blood vitamin D levels and the risk of neonatal sepsis in premature infants.

Clinical outcome and risk factors of neonatal sepsis among neonates in Felege Hiwot referral Hospital, Bahir Dar, Amhara Regional State, North West Ethiopia 2016: a retrospective chart review

BACKGROUND

Sepsis remains a major cause of morbidity and mortality among neonates. The risk factors and clinical outcomes of sepsis are poorly understood. Most cases of sepsis occurred mostly within the first week of newborns life related to perinatal risk factors. Late onset sepsis is related to hospital acquired infections which is seen after seven days of age. The purpose of this study was to assess clinical outcome and risk factors of neonatal sepsis in Felege Hiwot referral hospital Bahir Dar, North West Ethiopia.

RESULTS

Among the total 225 neonatal charts reviewed; 164 (72.9%) were age less than or equal to 7 days, and 144 (64%) were males. About 29 (12.9%) neonates were with irregular respiratory signs and 40 (17.8%) had meconium aspiration syndrome. Regarding the clinical outcome of neonatal sepsis: 189 (84%) were improved after treatment, 9 (4%) were died and 13 (5.8%) referred to other organizations for further treatment. Respiratory distress syndrome [AOR = 0.258 (0.072-0.930)] and meconium aspiration syndrome [AOR = 0.1989 (0.059-0.664)] were the determinant factors for poor outcome of neonatal sepsis.

CONCLUSION

The clinical outcome of neonatal sepsis in Felege Hiwot referral hospital was not satisfactory. The significant risk factors for poor outcome of neonatal sepsis were respiratory distress syndrome and meconium aspiration syndrome. Recommendations to improve neonatal outcome are: performing essential newborn care for all newborns and arranging appropriate follow up until the end of neonatal period, increasing antenatal care and early detection and management of neonatal infections or problems.

Relationship between blood lactic acid, blood procalcitonin, C-reactive protein and neonatal sepsis and corresponding prognostic significance in sick children

The study was conducted to evaluate the relationship between the blood lactic acid (BLA) level, serum procalcitonin (PCT), C-reactive protein (CRP) and the severity and prognosis of neonatal sepsis. A retrospective analysis was conducted on 90 children with sepsis admitted into the Intensive Care Unit (ICU) of the Hubei Institute for Nationalities Af liated Hospital hospital. Patients were divided into the non-survival group and the survival group. Severity of the 90 patients was evaluated according to Neonatal Critical Illness Score (NCIS). Observations were made on changes of the levels of BLA, PCT and CRP, correlation between BLA, PCT, CRP and NCIS as well as the association of the levels of these proteins with the prognosis of the patients. The 90 sick children were divided into the survival group (61 cases, 67.7%) and the non-survival group (29 cases, 32.2%). They were further stratified into the extremely severe group (n=20), severe group (n=39) and non-severe group (n=31) according to NCIS scoring standard. The BLA and NCIS scores of the non-survival group were significantly greater than those of the survival group. The difference was statistically significant (P<0.05). We found that there was a significant negative correlation between the BLA values and NCIS scores of the two groups. We also demonstrated significant positive correlation between the BLA value, PCT and CR (P<0.05). We observed a significant negative correlation between PCT, CRP and NCIS scores (P<0.05). The PCT level of the non-survival group was significantly higher than that of the survival group (P<0.05), while the NCIS score was significantly lower than that of the survival group (P<0.05). The CRP and PCT protein expression results of the sepsis patients were higher than those of the control group. Therefore, there is a significant correlation between BLA, CRP, PCT and NCIS. The lower the NCIS score is, the more significant the increase of BLA, PCT and CRP. Thus, the combined detection of levels of BLA, PCT and CRP may predict the severity of neonatal sepsis patients and their prognosis.

Unique aspects of the perinatal immune system

The early stages of life are associated with increased susceptibility to infection, which is in part due to an ineffective immune system. In the context of infection, the immune system must be stimulated to provide efficient protection while avoiding insufficient or excessive activation. Yet, in early life, age-dependent immune regulation at molecular and cellular levels contributes to a reduced immunological fitness in terms of pathogen clearance and response to vaccines. To enable microbial colonization to be tolerated at birth, epigenetic immune cell programming and early life-specific immune regulatory and effector mechanisms ensure that vital functions and organ development are supported and that tissue damage is avoided. Advancement in our understanding of age-related remodelling of immune networks and the consequent tuning of immune responsiveness will open up new possibilities for immune intervention and vaccine strategies that are designed specifically for early life.

Bacterial etiologic agents causing neonatal sepsis and associated risk factors in Gondar, Northwest Ethiopia

Background

Neonatal sepsis is a blood stream infection which is seen in the first month of life of the neonate. Bacterial profile of neonatal septicemia is constantly changing thus, current knowledge on the patterns of bacterial isolates, its antibiotic resistance profile, and associated factors, are essential to design and implement appropriate interventions. Therefore, the aim of this study was to identify bacterial etiologic agents, their antimicrobial susceptibility pattern and associated risk factors of neonatal sepsis among neonates.

Methods

A cross- sectional study was conducted among neonates suspected to sepsis attending University of Gondar Hospital from September/2015 to May/2016. A total of 251 consecutive neonates with clinical sign and symptoms of sepsis were included in the study. Blood sample was collected and directly inoculated into Trypton soya broth bottle and incubated at 37 °C. After 24 h of incubation it was sub- cultured in to blood agar plate, chocolate agar plate, manitol salt agar and Macconkey. The bacterial pathogens and antimicrobial susceptibility tests were identified using standard microbiological methods. Bivariate and multivariate logistic regressions were used to identify possible associated risk factors. Prior to the study ethical clearance was obtained from the School of Biomedical and Laboratory Sciences, University of Gondar.

Results

Of the 251 study participants suspected of neonatal sepsis, 117 (46.6%) showed bacterial growths, of them 120 bacteria were isolated. Gram positive bacteria were commonly isolated 81 (67.5%).The commonly isolated bacterial species were S. aureus 49 (40.8%) followed by coagulase negative Staphylococci 26 (21.6%) and K. pneumoniae19 (15.8%). The overall rate of multidrug resistance isolates was 78 (65%: CI 95%: 56.7–72.5%). Multidrug resistant (MDR) among Gram positive and negative bacteria were 56 (69.1%) and 22 (56.4%), respectively. Independent risk factors for the occurrence of neonatal sepsis were; Apgar score < 7/5 min (Adjusted odds ratio [AOR] =0.5), birth weight < 1.5 kg (AOR = 12.37), birth weight, 1.5–2.5 kg (AOR = 2.6), gestational week <37 weeks (AOR = 9) and caesarian section delivery (AOR = 5.2).

Conclusion

The isolation rate of bacterial pathogens in neonatal sepsis was considerably high. In addition, nearly 70% of isolates were MDR strains. Low birth weight, low Apgar score, preterm delivery and caesarian section modes of delivery were associated risk factors. Therefore, appropriate antenatal care follow up, and health education should be encouraged, especially on the importance of natural way of delivery.

Electronic supplementary material

The online version of this article (doi:10.1186/s12887-017-0892-y) contains supplementary material, which is available to authorized users.

Multidrug-resistant organisms in neonatal sepsis in two tertiary neonatal ICUs, Egypt

BACKGROUND

Neonatal sepsis remains a serious problem in any neonatal intensive care unit (NICU). Bacterial organisms have developed increased resistance to commonly used antibiotics. Because not enough data are available from Egypt, the aim of the present study was to determine the causative bacteria and the level of their resistance to commonly used antibiotics in tertiary NICUs in Cairo, Egypt.

MATERIALS AND METHODS

A 3.5-year retrospective study was carried out at NICUs of the Children's Hospital of Ain Shams University and that of El-Hussein Hospital, Al-Azhar University, Egypt. Records of neonates were reviewed. All neonates with culture-proven sepsis were included in the study.

RESULTS

Almost one-third of the admitted neonates (33.4%) were diagnosed as having neonatal sepsis, 32.25% of them culture-proven. Early/late onset sepsis was found in 35.4 and 64.6%, respectively. Gram-negative/gram-positive bacteria was found in 68 to 25.6%. Fungal infection was detected in 9% of the isolates. Escherichia coli was the main pathogen isolated in both early-onset sepsis (41.2%) and late-onset sepsis (24.5%). Overall, 77% of the isolates were multidrug-resistant (60% of gram-positive bacteria and 83.4% of gram-negative bacteria). Nearly 80% (79%) of mortality was caused by multidrug-resistant organisms. Gram-positive and gram-negative bacteria showed high resistance against commonly used antibiotics such as ampicillin, amoxicillin, cefotaxime, ceftriaxone, and gentamicin.

CONCLUSION AND RECOMMENDATIONS

There is an alarming increase in antibiotic resistance to the commonly used antibiotics. Continuous surveillance for antibiotic susceptibility is needed to ensure proper empirical therapy. Improvement of infection control practices, avoidance of irrational use of antibiotics, and revision of the protocols are mandatory in the prevention of neonatal sepsis.

Potential biomarkers for effective screening of neonatal sepsis infections: An overview

Neonatal sepsis, a clinical disorder developed by bacterial blood stream infections (BSI) in neonates, is one of the serious global public health problems that must be addressed. More than one million of the estimated global newborn deaths per year are occurred due to severe infections. The genesis of the infection is divided into early-onset sepsis (EOS) and late-onset sepsis (LOS) of the disease. The clinical complications of neonatal sepsis may be associated with bronchopulmonary dysplasia, ductus arteriosus and necrotizing enterocolitis. The clinical diagnosis and treatment of neonatal sepsis is highly complicated. Over the past few years distinct biomarkers have been identified. Most widely used biomarkers are C-reactive protein, Procalcitonin (PCT) and Serum amyloid A (SAA). Until recently, many potential biomarkers including Cell Surface antigens and Bacterial surface antigens and genetic biomarkers are being investigated. Protein biomarkers, cytokines and chemokines are getting much interest for identification of neonatal sepsis infection.

The Determination of Procalcitonin Concentration in Early-Onset Neonatal Infection

The aim of this study was to assess the clinical usefulness of blood procalcitonin (PCT) levels for the diagnosis and therapeutic monitoring of early-onset neonatal sepsis (EONS). PCT as well as C-reactive protein (CRP) levels and white blood cell (WBC) count were measured in venous blood from 57 infected and 72 uninfected neonates. Differences between groups for PCT, CRP, and WBC levels were significant. The threshold value on the receiver operating characteristic curve in the prediction of EONS was 5.33 ng/mL for PCT, 9.3 mg/L for CRP, and 14.9 × 10⁹/L for WBC. There was no effect of antibiotic administered to the mother on PCT, CRP, and WBC levels in neonatal blood sampled before treatment of EONS. Evidently reduced PCT levels are observed after 2 days of treatment. The authors conclude that prenatal antibiotic therapy does not reduce the value of PCT levels in blood for the diagnosis of EONS.

Copper to Zinc Ratio as Disease Biomarker in Neonates with Early-Onset Congenital Infections

Copper (Cu) and zinc (Zn) are essential trace elements for regular development. Acute infections alter their metabolism, while deficiencies increase infection risks. A prospective observational case-control study was conducted with infected (n = 21) and control (n = 23) term and preterm newborns. We analyzed trace element concentrations by X-ray fluorescence, and ceruloplasmin (CP) by Western blot. Median concentration of Cu at birth (day 1) was 522.8 [387.1-679.7] μg/L, and Zn was 1642.4 ± 438.1 μg/L. Cu and Zn correlated positively with gestational age in control newborns. Cu increased in infected newborns from day 1 to day 3. CP correlated positively to Cu levels at birth in both groups and on day 3 in the group of infected neonates. The Cu/Zn ratio was relatively high in infected newborns. Interleukin (IL)-6 concentrations on day 1 were unrelated to Cu, Zn, or the Cu/Zn ratio, whereas C-reactive protein (CRP) levels on day 3 correlated positively to the Cu/Zn -ratio at both day 1 and day 3. We conclude that infections affect the trace element homeostasis in newborns: serum Zn is reduced, while Cu and CP are increased. The Cu/Zn ratio combines both alterations, independent of gestational age. It may, thus, constitute a meaningful diagnostic biomarker for early-onset infections.

Impact of Latency Duration on the Prognosis of Preterm Infants after Preterm Premature Rupture of Membranes at 24 to 32 Weeks' Gestation: A National Population-Based Cohort Study

OBJECTIVE

To assess the impact of latency duration on survival, survival without severe morbidity, and early-onset sepsis in infants born after preterm premature rupture of membranes (PPROM) at 24-32 weeks' gestation.

STUDY DESIGN

This study was based on the prospective national population-based Etude Épidémiologique sur les Petits Ȃges Gestationnels 2 cohort of preterm births and included 702 singletons delivered in France after PPROM at 24-32 weeks' gestation. Latency duration was defined as the time from spontaneous rupture of membranes to delivery, divided into 4 periods (12 hours to 2 days [reference], 3-7 days, 8-14 days, and >14 days). Multivariable logistic regression was used to assess the relationship between latency duration and survival, survival without severe morbidity at discharge, or early-onset sepsis.

RESULTS

Latency duration ranged from 12 hours to 2 days (18%), 3-7 days (38%), 8-14 days (24%), and >14 days (20%). Rates of survival, survival without severe morbidity, and early-onset sepsis were 93.5% (95% CI 91.8-94.8), 85.4% (82.4-87.9), and 3.4% (2.0-5.7), respectively. A crude association found between prolonged latency duration and improved survival disappeared on adjusting for gestational age at birth (aOR 1.0 [reference], 1.6 [95% CI 0.8-3.2], 1.2 [0.5-2.9], and 1.0 [0.3-3.2] for latency durations from 12 hours to 2 days, 3-7 days, 8-14 days, and >14 days, respectively). Prolonged latency duration was not associated with survival without severe morbidity or early-onset sepsis.

CONCLUSION

For a given gestational age at birth, prolonged latency duration after PPROM does not worsen neonatal prognosis.

Pathogenic bacteria distributions and drug resistance analysis in 96 cases of neonatal sepsis

Background

This study aimed to summarize common pathogens and associated drug resistance in neonatal sepsis (NS).

Methods

Blood culture and drug sensitivity results from 96 NS cases treated from January 2010 to August 2014 were retrospectively analyzed.

Results

A total of 97 pathogenic bacteria were detected from these 96 NS cases; Gram-positive cocci accounted for 76.3% of the cases, among which 70.1% involved coagulase-negative staphylococcus (CONS), whereas Gram-negative bacilli and fungi accounted for 19.6% and fungi 4.1% of cases, respectively. Gram-positive cocci exhibited a higher penicillin resistance rate and full vancomycin sensitivity, whereas Gram-negative bacilli exhibited a higher cephalosporin resistance rate, low meropenem resistance rate (6.7%), and no resistance to amikacin.

Conclusions

The main causative pathogens of NS in our hospital were Gram-positive cocci, among which coagulase-negative Staphylococcus spp such as S. epidermidis and S. haemolyticus were the main conditional pathogens; among Gram-negative pathogens, Klebsiella pneumoniae were most frequently isolated and showed widespread resistance to penicillins and cephalosporins.

Immunoregulation effects of different γδT cells and toll-like receptor signaling pathways in neonatal necrotizing enterocolitis

The aim of the study was to observe cytokine and T-cell-related toll-like-receptor (TLR) changes in intestinal samples of neonatal necrotizing enterocolitis patients.Four necrotic bowels were collected from neonatal NEC patients with gestational ages of 28 to 29 weeks in our hospital, whereas 4 neonatal patients who underwent intestinal atresia surgery served as the controls. Intestinal flora was examined and IL-1, IL-2, IL-4, IL-6, IL-8, IL-10, TNF-α, IFN-γ, and IL-17 expressions in resected intestine samples, as well as in isolated gamma delta T (γδT) cells, were analyzed immunohistochemically and via quantitative RT-PCR. γδT cells were isolated from the intestinal intraepithelial lymphocytes (IELs) and their TLR4/TLR9 distribution in the intestinal tissues was determined by flow cytometry.The bacterial flora of the neonatal NEC patients' contained significantly higher amounts of Gram-negative Enterobacteriaceae, Klebsiella, and Bacteroides but anaerobic Gram-positive Bifidobacteria occurred significantly less in the NEC than the control group. IL-1, IL-2, IL-4, IL-6, IL-8, IL-10, TNF-α, IFN-γ, and IL-17 expressions in the resected intestine samples and in isolated γδT cells were enhanced in NEC samples compared to the controls. γδT cells were less prevalent in NEC-derived intestinal tissues, but their TLR4/TLR9 expressions were significantly enhanced.The changed bacterial flora in preterm neonatal NEC patients led to an obvious inflammation of the intestines, which was accompanied by reductions of γδT cell localizations to the intestine and a shift of their surface expressions to TLR4 and TLR9.

From Immunologically Archaic to Neoteric Glycovaccines

Polysaccharides (PS) are present in the outermost surface of bacteria and readily come in contact with immune cells. They interact with specific antibodies, which in turn confer protection from infections. Vaccines with PS from pneumococci, meningococci, Haemophilus influenzae type b, and Salmonella typhi may be protective, although with the important constraint of failing to generate permanent immunological memory. This limitation has in part been circumvented by conjugating glycovaccines to proteins that stimulate T helper cells and facilitate the establishment of immunological memory. Currently, protection evoked by conjugated PS vaccines lasts for a few years. The same approach failed with PS from staphylococci, Streptococcus agalactiae, and Klebsiella. All those germs cause severe infections in humans and often develop resistance to antibiotic therapy. Thereby, prevention is of increasing importance to better control outbreaks. As only 23 of more than 90 pneumococcal serotypes and 4 of 13 clinically relevant Neisseria meningitidis serogroups are covered by available vaccines there is still tremendous clinical need for PS vaccines. This review focuses on glycovaccines and the immunological mechanisms for their success or failure. We discuss recent advances that may facilitate generation of high affinity anti-PS antibodies and confer specific immunity and long-lasting protection.

Blood Level of Inter-Alpha Inhibitor Proteins Distinguishes Necrotizing Enterocolitis From Spontaneous Intestinal Perforation

OBJECTIVE

To examine circulating levels of inter-alpha inhibitor protein (IaIp) in infants with necrotizing enterocolitis (NEC), spontaneous intestinal perforation (SIP), and matched controls to assess the diagnostic accuracy of IaIp to differentiate NEC from SIP and to compare receiver operating characteristics of IaIp for NEC with C-reactive protein (CRP).

STUDY DESIGN

A prospective, nested case-control study of infants with feeding intolerance was carried out. Blood and clinical data were collected from 27 infants diagnosed with NEC or SIP and from 26 matched controls admitted to our unit. Infants with modified Bell criteria stage 2 or greater were included as NEC. Clinical, radiologic, and/or surgical findings were used to identify infants with SIP. Controls were matched for gestational age, postnatal age, sex, and birth weight.

RESULTS

Mean ± SD IaIp blood levels were 147 ± 38 mg/L, 276 ± 67 mg/L, and 330 ± 100 mg/L in infants with NEC, SIP, and matched controls, respectively (P < .004 and P < .01). Receiver operating characteristics analysis to establish the predictive value of NEC demonstrated areas under curve of 0.98 and 0.63 for IaIp and CRP, respectively.

CONCLUSIONS

IaIp levels were significantly decreased in infants with NEC compared with SIP and matched controls. The diagnostic accuracy of IaIp for NEC was superior to that of CRP.

Maternal Immunization With an Investigational Trivalent Group B Streptococcal Vaccine: A Randomized Controlled Trial

OBJECTIVE

To evaluate the safety and immunogenicity of an investigational trivalent group B streptococcal vaccine in pregnant women and antibody transfer to their newborns.

METHODS

The primary outcome of this observer-blind, randomized study was to estimate placental antibody transfer rates at birth. Secondary outcomes included measurement of serotype-specific antibodies at screening, 30 days postvaccination, at delivery, and 91 days postpartum, infant antibody levels at 3 months of age, the potential effect on routine infant diphtheria vaccination at 1 month after the third infant series dose, and safety in mother and infant participants through at least 5 months postpartum. Sample size was based on 60 participants in the vaccine group giving a probability of observing at least one adverse event of 90% if the actual rate of the event was 3.8%.

RESULTS

From September 2011 to October 2013, 86 pregnant women were allocated in a 3:2 ratio to receive an investigational group B streptococcal vaccine containing glycoconjugates of serotypes Ia, Ib, and III or placebo. Demographics were similar across groups. Transfer ratios were 66-79% and maternal geometric mean concentrations increased 16-, 23-, and 20-fold by delivery against serotypes Ia, Ib, and III, respectively, Women with no detectable antibodies at inclusion had lower responses than those with detectable antibodies. Three months after birth, infant antibody concentrations were 22-25% of birth levels. Antidiphtheria geometric mean concentrations were similar across groups. In the vaccine and placebo groups, 32 of 51 women (63%) and 26 of 35 women (74%) reported adverse effects, respectively.

CONCLUSION

The investigational vaccine was well-tolerated without safety signals in recipients and their infants or interference with routine infant diphtheria vaccination, although further studies on safety and effectiveness are needed. The investigational vaccine was immunogenic for all serotypes, particularly among women with detectable antibody levels at baseline. Antibody transfer to neonates was at similar levels to other maternally administered polysaccharide vaccines.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, www.clinicaltrials.gov, NCT01446289.

Flow cytometric white blood differential using CytoDiff™ in the diagnosis of neonatal early-onset infection

OBJECTIVE

Neonatal early-onset infection is a life-threatening disease, requiring early diagnosis and treatment. Newborns at risk are identified by a combination of risk factors, clinical signs of infection and laboratory parameters such as white blood cell count and C-reactive protein (CRP). This method is labor-intensive, time consuming and has a variable reproducibility. New reliable diagnostic markers are needed to identify neonatal infection. This study presents additional leukocyte differential parameters produced by the automated flow cytometry and processing software using CytoDiff™ reagent (Beckman Coulter) in newborns suspected for early-onset infection.

METHODS

An analytic prospective observational case-control study was performed in which 185 newborns were included and retrospectively allocated into two groups, "infection likely" and "infection unlikely". Leukocyte parameters of the CytoDiff™ technique were compared with microscopic slide differentiation and routine tests.

RESULTS

We showed significant lower numbers of monocytes, CD16(-) monocytes and lymphocytes (including T+/NK-lymphocytes) in neonates suspected for early-onset infection using CytoDiff™ technique. The manual counting did not demonstrate changes with respect to the number of monocytes in these neonates.

CONCLUSIONS

The automated routine CytoDiff™ leukocyte differential provides an interesting additional diagnostic tool, next to routine laboratory diagnostics, in the diagnosis of neonatal early-onset infection.