Intra-amniotic infection and/or inflammation (IAI) are important causes of preterm birth and early-onset neonatal sepsis (EONS). A prompt and accurate diagnosis of EONS is critical for improved neonatal outcomes. We sought to explore the cord blood proteome and identify biomarkers and functional protein networks characterizing EONS in preterm newborns.
We studied a prospective cohort of 180 premature newborns delivered May 2004-September 2009. A proteomics discovery phase employing two-dimensional differential gel electrophoresis (2D-DIGE) and mass spectrometry identified 19 differentially-expressed proteins in cord blood of newborns with culture-confirmed EONS (n = 3) versus GA-matched controls (n = 3). Ontological classifications of the proteins included transfer/carrier, immunity/defense, protease/extracellular matrix. The 1st-level external validation conducted in the remaining 174 samples confirmed elevated haptoglobin and haptoglobin-related protein immunoreactivity (Hp&HpRP) in newborns with EONS (presumed and culture-confirmed) independent of GA at birth and birthweight (P<0.001). Western blot concurred in determining that EONS babies had conspicuous Hp&HpRP bands in cord blood (“switch-on pattern”) as opposed to non-EONS newborns who had near-absent “switch-off pattern” (P<0.001). Fetal Hp phenotype independently impacted Hp&HpRP. A Bayesian latent-class analysis (LCA) was further used for unbiased classification of all 180 cases based on probability of “antenatal IAI exposure” as latent variable. This was then subjected to 2nd-level validation against indicators of adverse short-term neonatal outcome. The optimal LCA algorithm combined Hp&HpRP switch pattern (most input), interleukin-6 and neonatal hematological indices yielding two non-overlapping newborn clusters with low (≤20%) versus high (≥70%) probability of IAI exposure. This approach reclassified ∼30% of clinical EONS diagnoses lowering the number needed to harm and increasing the odds ratios for several adverse outcomes including intra-ventricular hemorrhage.
Antenatal exposure to IAI results in precocious switch-on of Hp&HpRP expression. As EONS biomarker, cord blood Hp&HpRP has potential to improve the selection of newborns for prompt and targeted treatment at birth.
To evaluate umbilical cord interleukin (IL)-6 and funisitis as independent predictors of early-onset neonatal sepsis (EONS) in preterm prelabor rupture of membranes (PPROM).
Prospective cohort study.
Evaluation of umbilical cord IL-6 and funisitis as predictors of early-onset neonatal sepsis in PPROM.
176 women with PPROM between 23+0−36+6 weeks of gestation.
Umbilical cord IL-6 was assayed by ELISA. Funisitis was defined according to the Salafia classification. Data was adjusted by gestational age at delivery and prenatal administration of corticosteroids and antibiotics.
Main Outcome Measures
Binary logistic regression was performed to assess the independence of umbilical cord IL-6 and funisitis to predict EONS in women complicated with PPROM.
The rate of EONS was 7%. Funisitis was present in 18% of women. Umbilical cord IL-6 was significantly higher in women complicated with EONS than without [median (range) 389.5 pg/mL (13.9–734.8) vs 5.2 (0.1–801–4), p<0.001]. Umbilical cord IL-6 was the only independent predictor of early-onset neonatal sepsis (odds ratio 13.6, p = 0.004).
Umbilical cord IL-6 was the only predictor of early-onset neonatal sepsis in PPROM. Contrary to what is reported, funisitis was not.
16S rRNA-based genomic analyses have revolutionized our understanding of infectious diseases. Many cases which were recognized as “idiopathic” are now known to have an infectious etiology. Here, we present a proof-of-concept study to examine the microbial link between intra-amniotic infection (IAI) and early-onset neonatal sepsis (EONS).
Using culture independent methods, we analyzed paired amniotic fluid (AF) and cord blood (CB) samples from 36 singleton pregnancies complicated by preterm birth (PTB), IAI, and/or EONS. PTB cases were grouped as 1) Group 1– neonatal blood culture-positive EONS (n = 6). 2) Group 2– neonatal blood culture-negative presumed EONS with positive IAI (n = 16). 3) Group 3– neonatal blood culture-negative presumed EONS with no IAI (n = 7); 4) Group 4– no EONS or IAI (n = 7). In addition, samples from term healthy deliveries (n = 8) served as technical controls. A total of 31 species (15 non-redundant) were identified in AF, of which only 1/3 were cultivated. Significantly fewer microorganisms were detected in CB, with a total of 18 species (7 non-redundant) identified, of which only 2 (Escherichia coli, Streptococcus agalactiae) were cultivated. Of those, Bergeyella, Fusobacterium nucleatum, and Sneathia sanguinegens had not been detected in EONS before. The novel species identified in AF by PCR include Peptoniphilus harei and Lachnospiraceae sp. The majority (72%) of CB species were also detected in the matching AF, with E. coli and F. nucleatum as the most prevalent. The 16S rRNA sequences of paired AF and CB were 99.9–100% identical, while no identical sequences were found between different pregnancies.
Previously unrecognized, uncultivated or difficult-to-cultivate species are implicated in EONS. Microbial species in paired AF and CB likely share the same infectious origin. Given its prevalence in EONS, F. nucleatum should be placed on the same importance scale as E. coli.
To identify the frequency of bacterial isolates in early-onset neonatal sepsis (EONS) and their antimicrobial resistance pattern.
A retrospective study of EONS was conducted at the Beni Suef University Hospital from September 2008 to September 2012. A case of EONS was defined as an infant who had clinical signs of infection or who was born to a mother with risk factors for infection, and in whom blood culture obtained within 72 hours of life grew a bacterial pathogen.
Of 673 neonates screened, there were 138 positive blood cultures (20.5%) (confirmed EONS). Of the recovered isolates, 86.2% were gram-negative pathogens. Klebsiella pneumoniae (42.8%), Enterobacter cloacae (22.5%), and Escherichia coli (13.8%) were the commonest isolated organisms. The most common gram-positive microorganism was Staphylococcus aureus accounting for only 12 isolates (8.7%). All Klebsiella isolates and 93% of Enterobacter isolates were resistant to ampicillin. Gram-negative pathogens had the maximum overall sensitivity to imipenem, cefepime, and ciprofloxacin; whereas, gram-positive isolates were most susceptible to vancomycin, imipenem, and piperacillin.
K. pneumoniae was the predominant causative bacteria of EONS followed by E. cloacae and E. coli. There was a high resistance to ampicillin. Imipenem had the maximum overall activity against the causative bacteria. Continuous surveillance is needed to monitor the changing epidemiology of pathogens and antibiotic sensitivity.
Drug Resistance; Newborn; Sepsis
Epidemiology and surveillance of neonatal sepsis helps in implementation of rational empirical antibiotic strategy.
To study the frequency of bacterial isolates of early onset neonatal sepsis (EONS) and their sensitivity pattern.
In this retrospective study, a case of EONS was defined as an infant who had clinical signs or born to mothers with potential risk factors for infection, in whom blood culture obtained within 72 hours of life, grew a bacterial pathogen. Blood culture sample included a single sample from peripheral vein or artery. Relevant data was obtained from the unit register or neonatal case records.
Of 2182 neonates screened, there were 389 (17.8%) positive blood cultures. After excluding coagulase-negative Staphylococci (160), we identified 229 EONS cases. Preterm neonates were 40.6% and small for gestational age, 18.3%. Mean birth weight and male to female ratio were 2344.5 (696.9) g and 1.16:1 respectively. Gram negative species represented 90.8% of culture isolates. Pseudomonas (33.2%) and Klebsiella (31.4%) were common among them. Other pathogens included Acinetobacter (14.4%), Staphylococcus aureus (9.2%), E.coli (4.4%), Enterobacter (2.2%), Citrobacter (3.1%) and Enterococci (2.2%). In Gram negative group, best susceptibility was to Amikacin (74.5%), followed by other aminoglycosides, ciprofloxacin and cefotaxime. The susceptibility was remarkably low to ampicillin (8.4%). Gram positive group had susceptibility of 42.9% to erythromycin, 47.6% to ciprofloxacin and above 50% to aminoglycosides. Of all isolates, 83.8% were susceptible to either cefotaxime or amikacin
Gram-negative species especially Pseudomonas and Klebsiella were the predominant causative organisms. Initial empirical choice of cefotaxime in combination with amikacin appeared to be rational choice for a given cohort.
Early onset sepsis; neonates; blood culture isolates; antibiotic susceptibility
The aim of this study was to determine whether maternal serum C-reactive protein (CRP) is of value in predicting funisitis and early-onset neonatal sepsis (EONS) in women with preterm labor or preterm premature rupture of membranes (PROM). This retrospective cohort study included 306 consecutive women with preterm labor or preterm PROM who delivered preterm singleton neonates (23-35 weeks gestation) within 72 hr of CRP measurement. The CRP level was measured with a highly sensitive immunoassay. The sensitivity, specificity, positive predictive value, and negative predictive value of an elevated serum CRP level (≥ 8 mg/L) were 74.1%, 67.5%, 32.8%, and 92.4% for funisitis, and 67.7%, 63.3%, 17.2%, and 94.6% for EONS, respectively. Logistic regression analysis demonstrated that elevated levels of serum CRP were significantly associated with funisitis and EONS, even after adjusting gestational age. The maternal serum CRP level obtained up to 72 hr before delivery is an independent predictor of funisitis and EONS in women with preterm labor or preterm PROM. A low serum CRP level (< 8 mg/L) has good negative predictive value in excluding funisitis and EONS, and may therefore be used as a non-invasive adjunct to clinical judgment to identify low-risk patients.
C-Reactive Protein; Early-Onset Neonatal Sepsis; Funisitis; Preterm Labor; Preterm Premature Rupture of Membrane
Neonatal sepsis can be classified into two subtypes depending upon whether the onset of symptoms is before 72 hours of life (early-onset neonatal sepsis—EONS) or later (late-onset neonatal sepsis—LONS). These definitions have contributed greatly to diagnosis and treatment by identifying which microorganisms are likely to be responsible for sepsis during these periods and the expected outcomes of infection. This paper focuses on the tools that microbiologist can offer to diagnose and eventually prevent neonatal sepsis. Here, we discuss the advantages and limitation of the blood culture, the actual gold standard for sepsis diagnosis. In addition, we examine the utility of molecular techniques in the diagnosis and management of neonatal sepsis.
Intra-uterine infection is viewed as a unique pathological process which raises considerably the risk for early onset neonatal sepsis (EONS). By acting synergistically with prematurity, EONS increases the risk for adverse neonatal outcomes including intraventricular hemorrhage (IVH) and cerebral palsy which are often encountered as sequelae of sepsis. Although several distinct pathways for the pathogenesis of fetal damage have been proposed, the basic molecular mechanisms that modulate these events remain incompletely understood. Therefore, discovery of clinically and biologically relevant biomarkers able to reveal key pathogenic pathways and predict pregnancies at risk for antenatal fetal damage is a priority. Proteomics provides a unique opportunity to fill this gap. In the short run proteomic biomarkers may aid with medical decision-making including timing of delivery and steroid administration In the long run proteomic biomarkers may lead to development of targeted therapies against pathogenic variants of EONS. Herein, we aimed to illustrate the richness of the topic and set the stage for the argument that discovery of novel proteomic biomarkers is a critical step in improving outcomes and preventing long-term disability.
newborn; sepsis; biomarkers; proteomics; DAMPs; RAGE
We hypothesized that abnormal fetal heart rate monitoring patterns (FHR-MP) occur more often in pregnancies complicated by intra-amniotic inflammation. Therefore, our objective was to examine the relationships between FHR-MP abnormalities, intra-amniotic inflammation and/or infection, acute histological chorioamnionitis and early-onset neonatal sepsis (EONS) in pregnancies complicated by preterm birth. Additionally, the ability of various FHR-MPs to predict EONS was investigated. FHR-MP from 87 singleton premature neonates delivered within 48 hours from amniocentesis [gestational age: 28.9 ± 3.3 weeks] were analyzed blindly using strict NICHD criteria. Strips were evaluated at three time points: at admission, at amniocentesis and prior to delivery. Intra-amniotic inflammation was established based on a previously validated proteomic fingerprint (MR score). Diagnoses of histological chorioamnionitis and EONS were based on well-recognized pathological, clinical and laboratory criteria. We determined that fetuses of women with severe intra-amniotic inflammation had a higher FHR baseline throughout the entire monitoring period and an increased frequency of a non-reactive FHR-MP at admission. Of all FHR-MP, a non-reassuring test at admission had 32% sensitivity, 95% specificity, 73% positive predictive value, 77% negative predictive value, and 76% accuracy in predicting EONS. Although a non-reassuring FHR-MP at admission was significantly associated with EONS after correcting for gestational age (OR: 5.6 [95%CI: 1.2–26.2], p=0.030), the majority of the neonates that developed EONS had an overall reassuring FHR-MP. Non-reassuring FHR-MPs at either amniocentesis or delivery had no association with EONS. We conclude that in cases complicated by preterm birth, a non-reassuring FHR-MP at the initial evaluation is a specific but not a sensitive predictor of EONS. An abnormal FHR-MP can thus raise the level of awareness that a fetus with EONS may be born, but is not a useful clinical indicator of the need for antibiotic treatment of the neonate.
To evaluate cord blood erythropoietin (EPO) and interleukin-6 (IL-6) levels to predict preterm infants at risk of developing intraventricular hemorrhage (IVH).
Levels of umbilical cord EPO, acid–base status and IL-6 were analyzed in 116 consecutive, preterm newborns (GA at delivery: 29 [23–34] weeks) born to mothers who had a clinically indicated amniocentesis to rule out infection. Early-onset neonatal sepsis (EONS) was diagnosed using symptoms, hematological criteria and blood cultures.
IVH was diagnosed by cranial ultrasounds. The prevalence of IVH in our population was 25% (29/116). There was a direct relationship between cord blood EPO and cord blood IL-6 concentration (r = 0.225, p = 0.014), independent of GA at birth. Elevated cord blood EPO levels (r = 0.182, p = 0.016) and GA birth at birth (r = –0.236, p = 0.004) remained significant independent factors associated with the risk of IVH, when evaluated with stepwise logistic regression analyses. Cord blood IL-6, pH, and EONS were not associated with IVH. These relationships remained following correction for GA at birth (p = 0.027).
Our results suggest that elevation in cord blood EPO may predict newborns at risk for IVH, independent of fetal inflammatory status. Further studies are warranted to confirm this association.
Erythropoietin; IL-6; premature; newborn; IVH
Early diagnosis and treatment of the newborn infant with suspected sepsis are essential to prevent severe and life threatening complications. Diagnosis of neonatal sepsis is difficult because of the variable and nonspecific clinical presentation. Therefore, many newborns with nonspecific symptoms are started on antibiotic treatment before the presence of sepsis has been proven. With our recently published single-centre intervention study we were able to show that Procalcitonin determinations allowed to shorten the duration of antibiotic therapy in newborns with suspected early-onset sepsis.
The study is designed as randomized controlled international multicenter intervention trial on the efficacy and safety of Procalcitonin guided treatment. Term and near-term infants (gestational age ≥ 34 0/7 weeks) with suspected sepsis in the first 3 days of life requiring empiric antibiotic therapy will be included. The duration of antibiotic therapy in the standard group is based on the attending physician's assessment of the likelihood of infection (infection unlikely, possible, probable or proven). In the Procalcitonin group, if infection is considered to be unlikely or possible, antibiotic therapy is discontinued when two consecutive Procalcitonin values are within the normal range. Co-primary outcome measures are the duration of antibiotic therapy (superiority aspect of the trial) and the proportion of infants with a recurrence of infection requiring additional courses of antibiotic therapy and/or death in the first month of life (safety of study intervention, non-inferiority aspect of the trial). The number of infants to be included equals 800 per arm. With these numbers the power of the study to demonstrate superiority for duration of antibiotic therapy as well as non-inferiority regarding safety, i.e. excluding a disadvantage difference larger than 2% for the experimental arm, will both be greater than 80%.
Benefit of the study is a possible limitation of unnecessary use of antibiotics. The results of our first study suggest that there is a low risk on discontinuing antibiotic treatment too early, resulting in the development of a neonatal infection with its morbidity and mortality.
This trial is registered in the U.S. National Institutes of Health's register, located at http://www.clinicaltrials.gov. (NCT00854932).
The incidence of neonatal early-onset sepsis has declined with the widespread use of intrapartum antibiotic therapies, yet early-onset sepsis remains a potentially fatal condition, particularly among very low-birth weight infants. Clinical signs of neonatal infection are non-specific and may be absent in the immediate postnatal period. Maternal and infant clinical characteristics, as well as infant laboratory values, have been used to identify newborns at risk, and to administer empiric antibiotic therapy to prevent progression to more severe illness. Such approaches result in the evaluation of approximately 15% of asymptomatic term and late preterm infants and of nearly all preterm infants. The development of multivariate predictive models may provide more accurate methods of identifying newborns at highest risk and allow for more limited newborn antibiotic exposures.
Early onset bacterial sepsis is a feared complication of the newborn. A large proportion of infants admitted to the Neonatal Intensive Care Unit (NICU) for suspected sepsis receive treatment with potent systemic antibiotics while a diagnostic workup is in progress. The gold standard for detecting bacterial sepsis is blood culture. However, as pathogens in blood cultures are only detected in approximately 25% of patients, the sensitivity of blood culture is suspected to be low. Therefore, the diagnosis of sepsis is often based on the development of clinical signs, in combination with laboratory tests such as a rise in C – reactive protein (CRP). Molecular assays for the detection of bacterial DNA in the blood represent possible new diagnostic tools for early identification of a bacterial cause.
A broad range 16S rDNA polymerase chain reaction (PCR) without preincubation was compared to conventional diagnostic work up for clinical sepsis, including BACTEC blood culture, for early determination of bacterial sepsis in the newborn. In addition, the relationship between known risk factors, clinical signs, and laboratory parameters considered in clinical sepsis in the newborn were explored.
Forty-eight infants with suspected sepsis were included in this study. Thirty-one patients were diagnosed with sepsis, only 6 of these had a positive blood culture. 16S rDNA PCR analysis of blinded blood samples from the 48 infants revealed 10 samples positive for the presence of bacterial DNA. PCR failed to be positive in 2 samples from blood culture positive infants, and was positive in 1 sample where a diagnosis of a non-septic condition was established. Compared to blood culture the diagnosis of bacterial proven sepsis by PCR revealed a 66.7% sensitivity, 87.5% specificity, 95.4% positive and 75% negative predictive value. PCR combined with blood culture revealed bacteria in 35.1% of the patients diagnosed with sepsis. Irritability and feeding difficulties were the clinical signs most often observed in sepsis. CRP increased in the presence of bacterial infection.
There is a need for PCR as a method to quickly point out the infants with sepsis. However, uncertainty about a bacterial cause of sepsis was not reduced by the PCR result, reflecting that methodological improvements are required in order for DNA detection to replace or supplement traditional blood culture in diagnosis of bacterial sepsis.
Group B streptococcus (GBS) remains the most common cause of early-onset sepsis in newborns. Laboratory gold-standard, broth culture methods are highly specific, but lack sensitivity. The aim of this study was to validate a nested-PCR and to determine whether residue volumes of urine samples obtained by non invasive, non sterile methods could be used to confirm neonatal GBS sepsis. The nested-PCR was performed with primers of the major GBS surface antigen. Unavailability of biological samples to perform life supporting exams, as well as others to elucidate the etiology of infections is a frequent problem concerning newborn patients. Nevertheless, we decided to include cases according to strict criteria: newborns had to present with signs and symptoms compatible with GBS infection; at least one of the following biological samples had to be sent for culture: blood, urine, or cerebrospinal fluid; availability of residue volumes of the samples sent for cultures, or of others collected on the day of hospitalization, prior to antibiotic therapy prescription, to be analyzed by PCR; favorable outcome after GBS empiric treatment. In only one newborn GBS infection was confirmed by cultures, while infection was only presumptive in the other three patients (they fulfilled inclusion criteria but were GBS-culture negative). From a total of 12 biological samples (5 blood, 3 CSF and 4 urine specimen), eight were tested by culture methods (2/8 were positive), and 8 were tested by PCR (7/8 were positive), and only 4 samples were simultaneously tested by both methods (1 positive by culture and 3 by PCR). In conclusion, although based on a restricted number of neonates and samples, our results suggest that the proposed nested-PCR might be used to diagnose GBS sepsis as it has successfully amplified the three types of biological samples analyzed (blood, urine and cerebrospinal fluid), and was more sensitive than culture methods as PCR in urine confirmed diagnosis in all four patients. Moreover, PCR has enabled us to use residue volumes of urine samples collected by non invasive, non sterile methods, what is technically adequate as GBS is not part of the normal urine flora, thus avoiding invasive procedures such as suprapubic bladder punction or transurethral catheterization. At the same time, the use of urine instead of blood samples could help preventing newborns blood spoliation.
GBS; neonatal sepsis; early-onset neonatal sepsis; neonatal infection; PCR; nested-PCR
Neonatal sepsis is a worldwide public health issue in which, depending on the studied population, marked variations concerning its risk and prognostic factors have been reported. The aim of this study was to assess risk and prognostic factors for neonatal sepsis prevailing at a medical unit in southeastern Mexico. Thus, we used a historic cohort design to assess the association between a series of neonates and their mothers, in addition to hospital evolution features and the risk and prognosis of neonatal sepsis (defined by Pediatric Sepsis Consensus [PSC] criteria) in 11,790 newborns consecutively admitted to a Neonatology Service in Mérida, Mexico, between 2004 and 2007.
Sepsis was found in 514 of 11,790 (4.3 %) newborns; 387 of these cases were categorized as early-onset (<72 h) (75.3 %) and 127, as late-onset (>72 h) (24.7 %). After logistic regression, risk factors for sepsis included the following: low birth weight; prematurity; abnormal amniotic fluid; premature membrane rupture (PMR) at >24 h; respiratory complications, and the requirement of assisted ventilation, O2 Inspiration fraction (IF) >60 %, or a surgical procedure. Some of these factors were differentially associated with early- or late-onset neonatal sepsis. The overall mortality rate of sepsis was 9.5 %. A marked difference in the mortality rate was found between early- and late-onset sepsis (p >0.0001). After Cox analysis, factors associated with mortality in newborns with sepsis comprised the following: prematurity; low birth weight; low Apgar score; perinatal asphyxia, and the requirement of any invasive medical or surgical procedure.
The incidence of neonatal sepsis in southeastern Mexico was 4.3 %. A different risk and prognostic profile between early- and late-onset neonatal sepsis was found.
Neonatal sepsis; Early-onset neonatal sepsis; Late-onset neonatal sepsis; Risk factors; Prognostic factors; Mortality
We present a methodology and database mediator tool for integrating modern knowledge-based systems, such as the Stanford EON architecture for automated guideline-based decision-support, with legacy databases, such as the Veterans Health Information Systems & Technology Architecture (VISTA) systems, which are used nation-wide. Specifically, we discuss designs for database integration in ATHENA, a system for hypertension care based on EON, at the VA Palo Alto Health Care System. We describe a new database mediator that affords the EON system both physical and logical data independence from the legacy VA database. We found that to achieve our design goals, the mediator requires two separate mapping levels and must itself involve a knowledge-based component.
National newborn screening programmes based on tandem-mass spectrometry (MS/MS) and other newborn screening (NBS) technologies show a substantial variation in number and types of disorders included in the screening panel. Once established, these methods offer the opportunity to extend newborn screening panels without significant investment and cost. However, systematic evaluations of newborn screening programmes are rare, most often only describing parts of the whole process from taking blood samples to long-term evaluation of outcome.
In a prospective single screening centre observational study 373 cases with confirmed diagnosis of a metabolic disorder from a total cohort of 1,084,195 neonates screened in one newborn screening laboratory between January 1, 1999, and June 30, 2009 and subsequently treated and monitored in five specialised centres for inborn errors of metabolism were examined. Process times for taking screening samples, obtaining results, initiating diagnostic confirmation and starting treatment as well as the outcome variables metabolic decompensations, clinical status, and intellectual development at a mean age of 3.3 years were evaluated.
Optimal outcome is achieved especially for the large subgroup of patients with medium-chain acyl-CoA dehydrogenase deficiency. Kaplan-Meier-analysis revealed disorder related patterns of decompensation. Urea cycle disorders, organic acid disorders, and amino acid disorders show an early high and continuous risk, medium-chain acyl-CoA dehydrogenase deficiency a continuous but much lower risk for decompensation, other fatty acid oxidation disorders an intermediate risk increasing towards the end of the first year. Clinical symptoms seem inevitable in a small subgroup of patients with very early disease onset. Later decompensation can not be completely prevented despite pre-symptomatic start of treatment. Metabolic decompensation does not necessarily result in impairment of intellectual development, but there is a definite association between the two.
Physical and cognitive outcome in patients with presymptomatic diagnosis of metabolic disorders included in the current German screening panel is equally good as in phenylketonuria, used as a gold standard for NBS. Extended NBS entails many different interrelated variables which need to be carefully evaluated and optimized. More reports from different parts of the world are needed to allow a comprehensive assessment of the likely benefits, harms and costs in different populations.
newborn screening; tandem-mass spectrometry
The use of the lumbar puncture in the diagnosis of central nervous system infection in acutely ill children is controversial. Recommendations have been published but it is unclear whether they are being followed.
The medical case notes of 415 acute medical admissions in a children's hospital were examined to identify children with suspected central nervous system infection and suspected meningococcal septicaemia. We determined whether lumbar punctures were indicated or contraindicated, whether they had been performed, and whether the results contributed to the patients' management.
Fifty-two children with suspected central nervous system infections, and 43 with suspected meningococcal septicaemia were identified. No lumbar punctures were performed in patients with contraindications, but only 25 (53%) of 47 children with suspected central nervous system infection and no contraindications received a lumbar puncture. Lumbar puncture findings contributed to the management in 18 (72%) of these patients, by identifying a causative organism or excluding bacterial meningitis.
The recommendations for undertaking lumbar punctures in children with suspected central nervous system infection are not being followed because many children that should receive lumbar punctures are not getting them. When they are performed, lumbar puncture findings make a useful contribution to the patients' management.
Ten percent of infants born in the United States are admitted to neonatal intensive care units (NICU) annually. Approximately one-half of these admissions are from term infants (>34 weeks of gestation) at risk for systemic infection. Most of the term infants are not infected but rather have symptoms consistent with other medical conditions that mimic sepsis. The current standard of care for evaluating bacterial sepsis in the newborn is performing blood culturing and providing antibiotic therapy while awaiting the 48-h preliminary result of culture. Implementing a more rapid means of ruling out sepsis in term newborns could result in shorter NICU stays and less antibiotic usage. The purpose of this feasibility study was to compare the utility of PCR to that of conventional culture. To this end, a total of 548 paired blood samples collected from infants admitted to the NICU for suspected sepsis were analyzed for bacterial growth using the BACTEC 9240 instrument and for the bacterial 16S rRNA gene using a PCR assay which included a 5-h preamplification culturing step. The positivity rates by culture and PCR were 25 (4.6%) and 27 (4.9%) positive specimens out of a total of 548 specimens, respectively. The comparison revealed sensitivity, specificity, and positive and negative predictive values of 96.0, 99.4, 88.9, and 99.8%, respectively, for PCR. In summary, this PCR-based approach, requiring as little as 9 h of turnaround time and blood volumes as small as 200 μl, correlated well with conventional blood culture results obtained for neonates suspected of having bacterial sepsis.
Neonatal sepsis is a common cause of morbidity and mortality among newborns in the developing world. We have investigated the causative agents and their antimicrobial susceptibility of late-onset sepsis (>72 h post-delivery), and determined the possible association between various risk factors and the mortality due to neonatal sepsis in 2008. To view the changes in years, we compared them with the data which we gained in 2004.
Medical records of all neonates with late-onset sepsis were reviewed for demographic characteristics (birth weight, gestational age, gender, type of delivery, and mortality rate), positive cultures and risk factors of mortality.
One hundred and forty-seven and 227 neonates had been diagnosed as late-onset sepsis in 2004 and 2008, respectively. Coagulase-negative staphylococcus was the most frequent microorganisms. Gram-negative bacilli, particularly Pseudomonas aeruginosa showed a significant increase in years. The mortality rate was 11.5% and 19% in 2004 and 2008, respectively. Birth weight, gestational age, and infection with Klebsiella spp. isolates were found to have significant association with sepsis mortality in our neonatal intensive care unit (NICU).
The present study emphasizes the importance of periodic surveys of sepsis encountered in particular neonatal setting to recognize the trend. Increased Gram-negative bacilli rate was possibly related to the widespread use of antibiotics in our NICU.
Sepsis; Risk factors; Neonatal intensive care unit; Neonate; Infection; Antibiotics
We evaluated the recent prevalence of serologic markers of hepatitis A virus (HAV) in South Korea.
The study data were the results of 60 126 anti-HAV (total) tests and 30 786 anti-HAV IgM tests that were performed during April 2009 through March 2010 by the Eone Reference Laboratory at the request of 1935 institutions throughout Korea.
The overall positivity rate was 51.06% on the anti-HAV (total) test and 11.20% on the anti-HAV IgM test. As compared with the other age groups the rate of anti-HAV (total) positivity was significantly lower (P < 0.001), and the rate of anti-HAV IgM positivity was significantly higher (P < 0.001), among Koreans aged 11 to 40 years. The seroprevalence of anti-HAV IgM significantly differed according to region but not by referral date.
This was the largest nationwide study in South Korea by 1 laboratory, and it provides useful recent baseline data on hepatitis A in Asia. The findings suggest that active immunization of younger Koreans should be made a priority.
hepatitis A virus; South Korea; immunization
Objectives: Many groups are developing computer-interpretable clinical guidelines (CIGs) for use during clinical encounters. CIGs use “Task-Network Models” for representation but differ in their approaches to addressing particular modeling challenges. We have studied similarities and differences between CIGs in order to identify issues that must be resolved before a consensus on a set of common components can be developed.
Design: We compared six models: Asbru, EON, GLIF, GUIDE, PRODIGY, and PROforma. Collaborators from groups that created these models represented, in their own formalisms, portions of two guidelines: the American College of Physicians–American Society of Internal Medicine’s guideline for managing chronic cough and the Sixth Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure.
Measurements: We compared the models according to eight components that capture the structure of CIGs. The components enable modelers to encode guidelines as plans that organize decision and action tasks in networks. They also enable the encoded guidelines to be linked with patient data—a key requirement for enabling patient-specific decision support.
Results: We found consensus on many components, including plan organization, expression language, conceptual medical record model, medical concept model, and data abstractions. Differences were most apparent in underlying decision models, goal representation, use of scenarios, and structured medical actions.
Conclusion: We identified guideline components that the CIG community could adopt as standards. Some of the participants are pursuing standardization of these components under the auspices of HL7.
Early identification of neonatal sepsis is a global issue because of limitations in diagnostic procedures. The objective of this study was to compare the diagnostic accuracy of neutrophil CD64 and C-reactive protein (CRP) as a single test for the early detection of neonatal sepsis.
A prospective study enrolled newborns with documented sepsis (n=11), clinical sepsis (n=12) and control newborns (n=14). CRP, neutrophil CD64, complete blood counts and blood culture were taken at the time of the suspected sepsis for the documented or clinical group and at the time of venipuncture for laboratory tests in control newborns. Neutrophil CD64 was analyzed by flow cytometry.
CD64 was significantly elevated in the groups with documented or clinical sepsis, whereas CRP was not significantly increased compared with controls. For documented sepsis, CD64 and CRP had a sensitivity of 91% and 9%, a specificity of 83% and 83%, a positive predictive value of 83% and 33% and a negative predictive value of 91% and 50%, respectively, with a cutoff value of 3.0 mg/dL for CD64 and 1.0 mg/dL for CRP. The area under the receiver-operating characteristic curves for CD64 index and CRP were 0.955 and 0.527 (P<0.01), respectively.
These preliminary data show that diagnostic accuracy of CD64 is superior to CRP when measured at the time of suspected sepsis, which implies that CD64 is a more reliable marker for the early identification of neonatal sepsis as a single determination compared with CRP.
Neutrophil CD64; C-reactive protein; Neonatal sepsis
The objective was to describe the characteristics of pediatric discharges associated with long-term mechanical ventilation (LTMV) compared with those with complex chronic conditions (CCCs), and evaluate trends over time in health care utilization for the discharges associated with LTMV.
The Kids' Inpatient Database, compiled by the Agency for Healthcare Research and Quality, was used. Routine newborn care was excluded. Discharges associated with LTMV were identified by using the International Classification of Diseases, Ninth Revision, code v46.1x and compared with discharges associated with CCCs in 2006 using simple regression and χ2 analyses. Trends in LTMV-associated discharges from 2000 to 2006 were assessed using variance-weighted least squares regression.
In 2006, there were an estimated 7812 discharges associated with LTMV. Compared with discharges for children with CCCs, LTMV discharges had significantly higher mortality, longer lengths of stay, higher mean charges, more emergency department admissions, and more discharges to long-term care. From 2000 to 2006, there was a 55% increase in the number of LTMV discharges and a concurrent 70% increase in aggregate hospital charges. The majority of LTMV discharges occurred in children 4 years old and younger, and ∼50% of the aggregate charges were for children younger than 1 year.
Discharges for children associated with LTMV require substantively greater inpatient resource use than other children with CCCs. As the number of discharges and associated aggregate charges increase over time, additional research must examine patterns of care for specific clinical subgroups of LTMV, especially children aged 4 years and younger.
mechanical ventilation; respiratory failure; utilization; hospitalization; Kids' Inpatient Database
The banded iron formation deposited during the first 2 billion years of Earth's history holds the key to understanding the interplay between the geosphere and the early biosphere at large geological timescales. The earliest ore-scale phosphorite depositions formed almost at ∼2.0–2.2 billion years ago bear evidence for the earliest bloom of aerobic life. The cycling of nutrient phosphorus and how it constrained primary productivity in the anaerobic world of Archean–Palaeoproterozoic eons are still open questions. The controversy centers about whether the precipitation of ultrafine ferric oxyhydroxide due to the microbial Fe(II) oxidation in oceans earlier than 1.9 billion years substantially sequestrated phosphate, and whether this process significantly limited the primary productivity of the early biosphere. In this study, we report apatite radial flowers of a few micrometers in the 2728 million-year-old Abitibi banded iron formation and the 2460 million-year-old Kuruman banded iron formation and their similarities to those in the 535 million-year-old Lower Cambrian phosphorite. The lithology of the 535 Million-year-old phosphorite as a biosignature bears abundant biomarkers that reveal the possible similar biogeochemical cycling of phosphorus in the Later Archean and Palaeoproterozoic oceans. These apatite radial flowers represent the primary precipitation of phosphate derived from the phytoplankton blooms in the euphotic zones of Neoarchean and Palaoeproterozoic oceans. The unbiased distributions of the apatite radial flowers within sub-millimeter bands do not support the idea of an Archean Crisis of Phosphate. This is the first report of the microbial mediated mineralization of phosphorus before the Great Oxidation Event when the whole biosphere was still dominated by anaerobic microorganisms.
Banded iron formation; great oxidation event; iron oxide; phosphate; Precambrian; primary productivity