C-reactive protein, interleukin-6, and procalcitonin in the immediate postnatal period: influence of illness severity, risk status, antenatal and perinatal complications, and infection

Understanding the Difficulties in Diagnosing Neonatal Sepsis: Assessing the Role of Sepsis Biomarkers

Background

Neonatal sepsis is a serious condition with high rates of morbidity and mortality, caused by the rapid growth of microorganisms that trigger a systemic reaction. Symptoms can range from mild to severe presentations. The causative microorganism is usually transmitted from mothers, especially from the urogenital tract, or can originate from the community or hospital.

Methods

Our retrospective study assessed 121 newborns, including both preterm and term infants, divided into three groups within the first 28 days of life: early-onset sepsis (35), late-onset sepsis (39), and a control group (47). Blood samples and cultures were obtained upon admission or at the onset of sepsis (at 24 and 72 hours). The study aimed to evaluate the limitations of commonly used biomarkers and new markers such as lactate dehydrogenase and ferritin in more accurately diagnosing neonatal sepsis.

Results

Our study revealed a significant difference between the initial and final measures of lactate dehydrogenase (LDH) and ferritin in the early-onset sepsis (EOS) and late-onset sepsis (LOS) groups.

Conclusion

Ferritin and LDH may serve as potential markers associated with systemic response and sepsis in cases of both early and late-onset sepsis. Monitoring these biomarkers can aid in the timely detection and management of sepsis, potentially improving patient outcomes.

A decade of neonatal sepsis in Stockholm, Sweden: Gram-positive pathogens were four times as common as Gram-negatives

PURPOSE

To assess Gram-positive bacterial (GPB) bloodstream infection (BSI) in neonates, covering incidence, morbidity, mortality, antimicrobial resistance patterns and biomarkers in Region Stockholm, Sweden between 2006 and 2016.

METHODS

A population-based retrospective epidemiological study including infants with GPB-BSI, admitted to the neonatal units at Karolinska University Hospital (KUH). Data were collected from patient records, the Swedish Neonatal Quality Register, the microbiological laboratory at KUH and the Swedish Public Health Agency.

RESULTS

We identified 357 infants with GPB-BSI, representing an incidence of 1.47/1000 live births (LB). Group B streptococcus (GBS) was the most common pathogen causing BSI in full-term infants and early-onset sepsis (EOS) (0.20/1000 LB), while coagulase-negative staphylococci (CoNS) were predominant in infants born very preterm and in late-onset sepsis (LOS) (0.79/1000 LB). There were no fatal GBS BSI cases, but 10.2% developed meningitis. The GPB case fatality rate was 9.5% and the sepsis fatality rate 2.8%. In GPB-BSI, 1/10 did not have an elevated C-reactive protein level. Staphylococcus aureus (S. aureus) BSI increased during the study period, but no methicillin or vancomycin resistant strains were found. The antimicrobial resistance (AMR) rate was highest in CoNS isolates.

CONCLUSION

GPB-BSI was four times more common than Gram-negative BSI in neonates but resulted in lower mortality rate. GBS was the most common pathogen in full-term infants and in EOS. CoNS was the most common pathogen in LOS and infants born very preterm, and the AMR rate was high in these isolates. The increasing trend of S. aureus BSI indicates a need of further investigation.

Incorporating anti-infective drugs into peripherally inserted catheters does not reduce infection rates in neonates

Purpose

This study assesses whether peripherally inserted central venous catheters (PICC), impregnated with anti-infective drugs, reduce the rate of infections in neonates compared with unimpregnated catheters.

Methods

A retrospective analysis was conducted on electronic patient records of neonates born between August 2014 and May 2020, who had PICCs inserted, either standard (S-PICC) or with anti-infective drugs (A-PICC). Catheter-related bloodstream infections (CRBSI) were diagnosed based on clinical symptoms, laboratory results, and mentioning of infection in the patient record. Data on dwell time, mechanical ventilation, insertion site, maximum C-reactive protein (CRP) concentration, and anti-infective drug use were analyzed.

Results

A total of 223 PICCs were included. The infection rates were A-PICC (18.9%) and S-PICC (12.5%), which were not significantly different (p = 0.257). A-PICCs had significantly longer dwell times than S-PICCs (median 372 vs. 219 h, p = 0.004). The time to infection was not different between the groups (p = 0.3). There were also no significant differences in maximum CRP, insertion site abnormalities, or anti-infective drug use between the groups.

Conclusion

This retrospective study did not find a significant reduction in infection rates by using PICCs containing anti-infective drugs in neonates. Current antibiotic impregnations do not seem to be effective in preventing blood stream infections.

Diagnostic Utility of Interleukin-6 in Early-Onset Sepsis among Term Newborns: Impact of Maternal Risk Factors and CRP Evaluation

(1) Background: Interleukin-6 (IL-6) levels act as an early infection marker preceding C-reactive protein (CRP) elevation. This study seeks to analyze IL-6 behavior in suspected early-onset sepsis (EOS) cases among term newborns, comparing it to that of CRP and evaluating IL-6's diagnostic utility. We also aim to assess the impact of maternal risk factors on EOS in term newborns, quantifying their influence for informed decision making. (2) Methods: The retrospective data analysis included 533 term newborns who were admitted to our hospital because of suspected EOS. IL-6, CRP, and the impact of maternal risk factors were analyzed in the context of EOS using binomial test, Chi-squared test, logistic and linear regression. (3) Results: In the cases of EOS, both IL-6 and CRP were elevated. The increase in CRP can be predicted by the initial increase in IL-6 levels. Among the assessed risk factors, intrapartum maternal fever (adjusted odds ratio 18.1; 95% CI (1.7-4.1)) was identified as the only risk factor significantly associated with EOS. (4) Conclusions: Employing IL-6 as an early infection marker enhanced EOS diagnostic precision due to its detectable early rise. However, caution is required, as elevations in IL-6 and CRP levels do not exclusively indicate EOS. Increased CRP levels in healthy newborns with maternal risk factors may be attributed to dynamics of vaginal labor.

Biomarkers of Neonatal Sepsis: Where We Are and Where We Are Going

Neonatal sepsis is a bacterial bloodstream infection leading to severe clinical manifestations frequently associated with death or irreversible long-term deficits. Antibiotics are the drug of choice to treat sepsis, regardless of age. In neonates, the lack of reliable criteria for a definite diagnosis and the supposition that an early antibiotic administration could reduce sepsis development in children at risk have led to a relevant antibiotic overuse for both prevention and therapy. The availability of biomarkers of neonatal sepsis that could alert the physician to an early diagnosis of neonatal sepsis could improve the short and long-term outcomes of true sepsis cases and reduce the indiscriminate and deleterious use of preventive antibiotics. The main aim of this narrative review is to summarize the main results in this regard and to detail the accuracy of currently used biomarkers for the early diagnosis of neonatal sepsis. Literature analysis showed that, despite intense research, the diagnosis of neonatal sepsis and the conduct of antibiotic therapy cannot be at present decided on the basis of a single biomarker. Given the importance of the problem and the need to reduce the abuse of antibiotics, further studies are urgently required. However, instead of looking for new biomarkers, it seems easier and more productive to test combinations of two or more of the presently available biomarkers. Moreover, studies based on omics technologies should be strongly boosted. However, while waiting for new information, the use of the clinical scores prepared by some scientific institutions could be suggested. Based on maternal risk factors and infant clinical indicators, sepsis risk can be calculated, and a significant reduction in antibiotic consumption can be obtained.

AACC Guidance Document on the Clinical Use of Procalcitonin

BACKGROUND

Procalcitonin (PCT), a peptide precursor of the hormone calcitonin, is a biomarker whose serum concentrations are elevated in response to systemic inflammation caused by bacterial infection and sepsis. Clinical adoption of PCT in the United States has only recently gained traction with an increasing number of Food and Drug Administration-approved assays and expanded indications for use. There is interest in the use of PCT as an outcomes predictor as well as an antibiotic stewardship tool. However, PCT has limitations in specificity, and conclusions surrounding its utility have been mixed. Further, there is a lack of consensus regarding appropriate timing of measurements and interpretation of results. There is also a lack of method harmonization for PCT assays, and questions remain regarding whether the same clinical decision points may be used across different methods.

CONTENT

This guidance document aims to address key questions related to the use of PCT to manage adult, pediatric, and neonatal patients with suspected sepsis and/or bacterial infections, particularly respiratory infections. The document explores the evidence for PCT utility for antimicrobial therapy decisions and outcomes prediction. Additionally, the document discusses analytical and preanalytical considerations for PCT analysis and confounding factors that may affect the interpretation of PCT results.

SUMMARY

While PCT has been studied widely in various clinical settings, there is considerable variability in study designs and study populations. Evidence to support the use of PCT to guide antibiotic cessation is compelling in the critically ill and in some lower respiratory tract infections but is lacking in other clinical scenarios, and evidence is also limited in the pediatric and neonatal populations. Interpretation of PCT results requires guidance from multidisciplinary care teams of clinicians, pharmacists, and clinical laboratorians.

Diagnostic Performance and Patient Outcomes With C-Reactive Protein Use in Early-Onset Sepsis Evaluations

OBJECTIVES

To determine performance of C-reactive protein (CRP) in the diagnosis of early-onset sepsis, and to assess patient outcomes with and without routine use of CRP.

STUDY DESIGN

This was a retrospective cohort study of infants admitted to 2 neonatal intensive care units. CRP was used routinely in early-onset sepsis evaluations during 2009-2014; this period was used to determine CRP performance at a cut-off of ≥10 mg/L in diagnosis of culture-confirmed early-onset sepsis. Routine CRP use was discontinued during 2018-2020; outcomes among infants admitted during this period were compared with those in 2012-2014.

RESULTS

From 2009 to 2014, 10 134 infants were admitted; 9103 (89.8%) had CRP and 7549 (74.5%) had blood culture obtained within 3 days of birth. CRP obtained ±4 hours from blood culture had a sensitivity of 41.7%, specificity 89.9%, and positive likelihood ratio 4.12 in diagnosis of early-onset sepsis. When obtained 24-72 hours after blood culture, sensitivity of CRP increased (89.5%), but specificity (55.7%) and positive likelihood ratio (2.02) decreased. Comparing the periods with (n = 4977) and without (n = 5135) routine use of CRP, we observed lower rates of early-onset sepsis evaluation (74.5% vs 50.5%), antibiotic initiation (65.0% vs 50.8%), and antibiotic prolongation in the absence of early-onset sepsis (17.3% vs 7.2%) in the later period. Rate and timing of early-onset sepsis detection, transfer to a greater level of care, and in-hospital mortality were not different between periods.

CONCLUSIONS

CRP diagnostic performance was not sufficient to guide decision-making in early-onset sepsis. Discontinuation of routine CRP use was not associated with differences in patient outcomes despite lower rates of antibiotic administration.

Discrimination of serum metabolomics profiles in infants with sepsis, based on liquid chromatography-mass spectrometer

Sepsis is one of the most important problems to be addressed in pediatrics, characterized by insidious onset, rapid progression, and high rates of severe infection and even mortality. Biomarkers with high sensitivity and robustness are urgently required for the early diagnosis of infant sepsis. Serum metabolomic approaches based on liquid chromatography-mass spectrometry were used to analyze the samples from 30 infants with sepsis at an early stage and 30 infants with noninfectious diseases. Multivariate statistical analysis was used to screen for differential metabolites and ROC curves were generated to find potential biomarkers. Six metabolites, including phosphatidic acid (PA (8:0/14:0)), phosphatidyl ethanolamine (PE (16:0/18:2(9Z,12Z))), cytidine 5'-diphosphocholine (CDP-CHO), sphingomyelin (SM (d18:0/16:1(9Z))), prolylhydroxyproline and phosphorylcholine (P-CHO), were identified between the two groups. ROC curve analysis showed that prolylhydroxyproline (AUC = 0.832) had potential diagnostic values for infant sepsis. The AUC value was 0.859 (CI: 0.764, 0.954) in the combined model. Prolylhydroxyproline were found to be correlated with CRP and PCT levels, while PE and CDP-CHO associated with PCT levels. Pathway analysis indicated that glycerophospholipid metabolism, aminoacyl-tRNA biosynthesis and necroptosis pathways played important roles in infant sepsis. Network analysis showed that the differential metabolites were linked to ERK/ MAPK, NF-κB, AMPK, mTOR, and other classical inflammatory and metabolic signaling pathways. This study identified serum metabolite profiles and three metabolites as potential biomarkers in infants with sepsis. The findings will help improve the early diagnosis of sepsis in infants.

The Value of Perinatal Factors, Blood Biomarkers and Microbiological Colonization Screening in Predicting Neonatal Sepsis

Background: Neonatal sepsis is one of the most important causes of elevated morbidity and mortality rates in neonatal intensive care units worldwide. While the clinical manifestations of neonatal sepsis tend to be nonspecific, its rapid development and life-threatening potential call for reliable markers for early detection. Methods: We conducted a retrospective single-center study including all neonates suspected of having developed neonatal sepsis from 2013 to 2016. Perinatal and clinical characteristics as well as microbiological and laboratory findings were evaluated. Neonatal sepsis was defined as either culture-proven sepsis (positive blood culture) or clinical sepsis (at least one symptom and elevated C-reactive protein (CRP) concentrations within 72 h with negative blood culture). We further differentiated between early-onset (EOS) and late-onset (LOS) sepsis. Results: Microbiological colonization screening by throat and rectal swabs frequently did not detect the organism that subsequently caused the sepsis. Depending on the age of the newborn with sepsis (EOS or LOS), associations between different anamnestic and clinical factors (prenatal or postnatal ones) were found. In particular, the central−peripheral temperature difference showed a strong association with LOS. Laboratory results useful for the early detection of neonatal sepsis included interleukin-6 (IL-6) and CRP concentrations. Conclusions: Elevated IL-6 >100 ng/L was a strong marker for neonatal sepsis. When choosing the antibiotics for treatment, data from microbiological colonization screening should be considered but not solely relied on. Some indicators of infection also depended on postnatal age.

Serial Measurement of Interleukin-6 Enhances Chance to Exclude Early-Onset Sepsis in Very Preterm Infants

The aim of this retrospective study was to evaluate the reliability of peak interleukin-6 (IL-6) level within 24 hours after delivery as a predictor for early-onset sepsis (EOS) in very preterm neonates. Interleukin-6 was assessed at 2 hours and at 12 to 24 hours after delivery. The highest level was considered a peak value. The definition of EOS was based on positive blood culture and clinical signs of infection or negative blood culture, clinical signs of infection, and C-reactive protein >10 mg/L. Among 445 enrolled infants, 53 developed EOS. A peak IL-6 level of more than 200 ng/L had a sensitivity of 89% and specificity of 77% for the presence of EOS. The negative predictive value was 98%. Receiver operating characteristics curve had area under the curve of 0.92. Peak IL-6 is a reliable marker of systemic inflammatory response and might be useful to exclude EOS within the first 24 hours.

Automated Complete Blood Cell Count Using Sysmex XN-9000® in the Diagnosis of Newborn Infection

The early identification of septically infected newborn infants is important for ensuring good outcomes. Blood cell differentiations are helpful, but they are often time consuming and inaccurate. In this study, we evaluated the use of automatic white blood cell differentiations by flow cytometry for the diagnosis of neonatal sepsis. Episodes of suspected infection in neonates were retrospectively classified into two groups, unlikely infection (UI, levels of Interleukin-6 < 400 pg/mL or CRP within 48 h < 10 mg/L), n = 101 and probable infection (PI, Interleukin-6 ≥ 400 pg/mL or CRP within 48 h ≥ 10 mg/L), n = 98. Complete blood cell counts were performed by Sysmex XN-9000® using flow cytometry. Relative and absolute proportions of immature granulocytes were evaluated. Unexpectedly, the absolute count of immature granulocytes was significantly lower in the group of PI compared to UI neonates. Similar results were found when analysing the relative proportion of immature granulocytes among all neutrophil granulocytes. On the other hand, manually counted immature to total (I/T) ratios of granulocytes were higher in PI than in UI infants. Therefore, we conclude that differentiations of granulocytes by Sysmex XN-9000® can be used to distinguish between infected and uninfected neonates if the results are interpreted according to our findings. A low count of immature granulocytes as determined by Sysmex XN-9000® may indicate neonatal infection.

Risk factors and postnatal biomarkers for acute placental inflammatory lesions and intrauterine infections in preterm infants

The purpose of this study is to explore risk factors of acute placental inflammatory lesions and the potential postnatal serum biomarkers for predicting the severity of intrauterine infection in preterm infants. We performed a retrospective analysis of premature infants with or without acute placental inflammatory lesions and their mothers by chart review for clinical data and placental histopathology. The preterm infants with acute placental inflammatory lesions had a higher rate of premature rupture of membranes (PROM), a longer duration of PROM, and a higher level of serum sialic acid (SIA) than those of the non-inflammation group (all p < 0.001). According to the different inflammatory histological structures, preterm infants with funisitis had a dominant longer duration of PROM than others (p < 0.05), and their gestational age was youngest among all the infants (p < 0.05). Furthermore, they had the highest content of serum SIA above other groups. The preterm infants in the acute histological chorioamnionitis group showed a similar trend of clinical manifestation and laboratory parameters with the funisitis group. Moreover, the closer the placental lesions were to the fetus, the lower the gestational age of preterm infants was, and the higher the serum SIA content was.

CONCLUSION

We utilized a simple and precise anatomically category method of placental inflammatory histopathology for pediatricians to distinguish the extent of fetal inflammatory response for representing early-onset infectious diseases of preterm infants. SIA might be one of the potential early-stage serum biomarkers to reflect the severe intrauterine infections and could guide the postnatal anti-infection treatment.

WHAT IS KNOWN

• Acute placental inflammatory lesion contributes to preterm birth and a series of complications in preterm infants. • C-reactive protein and interleukin-6 in neonatal blood can be used as biomarkers for potential early-onset sepsis, but they are influenced by the postnatal physiological changes of preterm infants.

WHAT IS NEW

• The value of serum sialic acids of preterm infants within 1-hour afterbirth may be one of the rapid postnatal biomarkers for evaluating the severity of intra-amniotic infection. • The closer the placental lesions are to the fetus, the higher the content of serum sialic acid is.

Presepsin for the Diagnosis of Neonatal Early-Onset Sepsis: A Systematic Review and Meta-analysis

Importance

Neonatal early-onset sepsis (EOS) is a severe disease, particularly in preterm infants. Timely diagnosis can be challenging owing to unspecific presentation and questionable performance of the common markers of infection. Presepsin was recently proven to be a promising biomarker for the diagnosis of EOS.

Objective

To assess presepsin accuracy for the diagnosis of EOS.

Data Sources

PubMed Medline, EMBASE, Web of Science, and Google Scholar. No publication date restrictions were applied. The literature search was limited to the English language. Articles were checked for duplication.

Study Selection

Inclusion criteria were studies that (1) included term or preterm newborns (defined as newborns with gestational age ≥37 weeks or <37 weeks, respectively); (2) included a diagnosis of EOS, defined as culture-proven sepsis for primary analysis and as either clinical or culture-proven sepsis for secondary analysis; and (3) assessed presepsin values during the initial workup for suspected EOS. Exclusion criteria were studies that (1) did not include EOS cases; (2) lacked data on presepsin sensitivity and/or specificity; and (3) were case reports, commentaries, or reviews. Two independent reviewers performed the study selection.

Data Extraction and Synthesis

Two independent reviewers performed data extraction and quality assessment. Quality assessment was performed using the Quality Assessment for Studies of Diagnostic Accuracy 2 tool, and data were reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Data were pooled using a random-effects model.

Main Outcomes and Measures

The outcomes of interest for both the primary and secondary analyses were presepsin sensitivity, specificity, and diagnostic odds ratio for the diagnosis of EOS.

Results

A total of 12 studies of 245 (4.9%) met inclusion criteria for the primary analysis. Twenty-three studies of 245 (9.4%) met the inclusion criteria for the secondary analysis. In the primary analysis, among 12 studies and 828 newborns of any gestational age, pooled sensitivity and specificity were 0.93 (95% CI, 0.86-0.95) and 0.91 (95% CI, 0.85-0.95), respectively; pooled diagnostic odds ratio was 131.69 (95% CI, 54.93-310.94). Subgroup analysis showed that presepsin specificity was associated with the inclusion of only EOS or all neonatal sepsis. Presepsin accuracy was not associated with gestational age, measurement with chemiluminescence enzyme immunoassay or enzyme-linked immunosorbent assay testing, country where the study was performed, or risk of bias judgment. In the secondary analysis, among 23 studies and 1866 newborns, accuracy was significantly associated with only test type.

Conclusions and Relevance

Results of this systematic review and meta-analysis suggest that presepsin was an accurate biomarker of EOS. Clinical trials are warranted to assess its usefulness and safety to reduce early antibiotic exposure, particularly in preterm newborns.

Cerebrospinal fluid and plasma procalcitonin for the diagnosis of neonatal bacterial meningitis

AIM

There is a paucity of data on cerebrospinal fluid (CSF) procalcitonin (PCT) to diagnose neonatal meningitis. We evaluated CSF PCT to diagnose bacterial meningitis among neonates with suspected sepsis.

METHODS

Neonates undergoing lumbar puncture (LP) as part of sepsis workup were included.

INDEX TESTS

CSF PCT, plasma PCT, CSF:plasma PCT ratio and CSF cytochemistry. Reference Standards: 'Definite meningitis' defined by positive CSF culture and/or gram stain and/or broad-based primer 16S rDNA polymerase chain reaction. 'Definite or probable' meningitis is defined as definite meningitis or abnormal cytochemistry.

RESULTS

Of 216 eligible neonates, 18 had 'definite meningitis' and 37 'definite or probable meningitis'. Median (Q₁ , Q₃ ) CSF PCT level was significantly higher in 'definite meningitis' compared to 'no definite meningitis' (0.429 (0.123, 1.300) vs. 0.181 (0.119, 0.286) ng/mL respectively, P = 0.028). Likewise, it was significantly higher in 'definite or probable meningitis' compared to no meningitis (0.245 (0.136, 0.675) vs. 0.170 (0.116, 0.28), P = 0.01). The area under the receiver operator characteristics curve of CSF PCT level for definite meningitis was 0.656 and for 'definite or probable meningitis' 0.635. Paired comparisons of area under the receiver operator characteristics curve of CSF PCT with the other index tests showed no significant differences. Based on a priori cut-off of 0.2 ng/mL, CSF PCT level had a sensitivity (95% confidence interval) of 67% (50, 80), specificity 58% (54, 61), LR⁺ 1.6 (1.1, 2.0) and LR^- 0.6 (0.3, 0.9).

CONCLUSIONS

Higher values of CSF PCT are associated with neonatal bacterial meningitis. However, the diagnostic performance of CSF PCT is modest and not significantly different from standard tests.

Neonatal Sequential Organ Failure Assessment (nSOFA) Score within 72 Hours after Birth Reliably Predicts Mortality and Serious Morbidity in Very Preterm Infants

The aim of this study was to assess the applicability of the neonatal sequential organ failure assessment score (nSOFA) within 72 h after delivery as a predictor for mortality and adverse outcome in very preterm neonates. Inborn neonates <32 weeks of gestation were evaluated. The nSOFA scores were calculated from medical records in the first 72 h after birth and the peak value was used for analysis. Death or composite morbidity at hospital discharge defined the adverse outcome. Composite morbidity consisted of chronic lung disease, intraventricular haemorrhage ≥grade III, periventricular leukomalacia and necrotizing enterocolitis. Among 423 enrolled infants (median birth weight 1070 g, median gestational age 29 weeks), 27 died and 91 developed composite morbidity. Death or composite morbidity was associated with organ dysfunction as assessed by nSOFA, systemic inflammatory response, and low birthweight. The score >2 was associated with OR 2.5 (CI 1.39−4.64, p = 0.002) for the adverse outcome. Area under the curve of ROC was 0.795 (95% CI = 0.763−0.827). The use of nSOFA seems to be reasonable for predicting mortality and morbidity in very preterm infants. It constitutes a suitable basis to measure the severity of organ dysfunction regardless of the cause.

The Correlation of Antibacterial Peptides Concentration in Umbilical Cord Blood and Early Onset Sepsis in Preterm Infants

Umbilical cord blood from singleton preterm infants was collected during delivery, and the concentration of LL37 was measured. C-reactive protein (CRP), white blood cell count (WBC), platelets (PLT), and mean platelet volume (MPV) were determined within 3 days after birth. The differences in LL37, CRP, WBC, PLT, and MPV levels between the two groups were compared. Pearson correlation method was used to analyze the correlation between these factors. The early individual value of each detected index for early onset sepsis was analyzed by ROC curve. The level of LL37 in umbilical cord blood of sepsis group was significantly higher than those in the control group (383.85 ± 46.71 vs. 252.37 ± 83.30 ng/ml). Meanwhile, the levels of CRP, WBC, and MPV in the sepsis group were significantly higher than those in the control group (CRP:5.73 ± 4.19 vs. 2.50 ± 2.77 mg/L; WBC: 13.47 ± 12.35 vs. 6.83 ± 3.55 × 109/L; MPV: 11.20 ± 1.11 vs. 8.90 ± 0.68 fL), the level of PLT was significantly lower than those in the control group (PLT: 161.00 ± 38.51 vs. 241.50 ± 49.85 × 109/L) (P < 0.05). Pearson correlation analysis showed that the expression of LL37 was negatively correlated with PLT level (r = -0.9347, P < 0.0001), and positively correlated with MPV level (r = 0.9463, P < 0.0001). ROC curve analysis showed that the area under curve of LL37 for diagnosis of early onset sepsis was 0.875, the prediction probability was 0.7, the sensitivity was 90.0% and the specificity was 80.0%.

Identifying Prokineticin2 as a Novel Immunomodulatory Factor in Diagnosis and Treatment of Sepsis

OBJECTIVES

Sepsis remains a highly lethal disease, whereas the precise reasons for death remain poorly understood. Prokineticin2 is a secreted protein that regulates diverse biological processes. Whether prokineticin2 is beneficial or deleterious to sepsis and the underlying mechanisms remain unknown.

DESIGN

Prospective randomized animal investigation and in vitro studies.

SETTING

Research laboratory at a medical university hospital.

SUBJECTS

Prokineticin2 deficiency and wild-type C57BL/6 mice were used for in vivo studies; sepsis patients by Sepsis-3 definitions, patient controls, and healthy controls were used to obtain blood for in vitro studies.

INTERVENTIONS

Prokineticin2 concentrations were measured and analyzed in human septic patients, patient controls, and healthy individuals. The effects of prokineticin2 on sepsis-related survival, bacterial burden, organ injury, and inflammation were assessed in an animal model of cecal ligation and puncture-induced polymicrobial sepsis. In vitro cell models were also used to study the role of prokineticin2 on antibacterial response of macrophages.

MEASUREMENTS AND MAIN RESULTS

Prokineticin2 concentration is dramatically decreased in the patients with sepsis and septic shock compared with those of patient controls and healthy controls. Furthermore, the prokineticin2 concentration in these patients died of sepsis or septic shock is significantly lower than those survival patients with sepsis or septic shock, indicating the potential value of prokineticin2 in the diagnosis of sepsis and septic shock, as well as the potential value in predicting mortality in adult patients with sepsis and septic shock. In animal model, recombinant prokineticin2 administration protected against sepsis-related deaths in both heterozygous prokineticin2 deficient mice and wild-type mice and alleviated sepsis-induced multiple organ damage. In in vitro cell models, prokineticin2 enhanced the phagocytic and bactericidal functions of macrophage through signal transducers and activators of transcription 3 pathway which could be abolished by signal transducers and activators of transcription 3 inhibitors S3I-201. Depletion of macrophages reversed prokineticin2-mediated protection against polymicrobial sepsis.

CONCLUSIONS

This study elucidated a previously unrecognized role of prokineticin2 in clinical diagnosis and treatment of sepsis. The proof-of-concept study determined a central role of prokineticin2 in alleviating sepsis-induced death by regulation of macrophage function, which presents a new strategy for sepsis immunotherapy.

Bacterial DNA detection in very preterm infants assessed for risk of early onset sepsis

OBJECTIVES

The aim of this study is to evaluate the diagnostic ability of multiplex real-time polymerase chain reaction (PCR) in very preterm infants assessed for risk of early onset neonatal sepsis (EOS).

METHODS

Prospective observational cohort study. Blood samples of preterm neonates ≤32 weeks of gestation were evaluated by commercial multiplex real-time PCR within 2 h after delivery. The definition of EOS was based on positive blood culture and clinical signs of infection or negative blood culture, clinical signs of infection and abnormal neonatal blood count and serum biomarkers.

RESULTS

Among 82 subjects analyzed in the study, 15 had clinical or confirmed EOS. PCR was positive in four of these infants (including the only one with a positive blood culture), as well as in 15 of the 67 infants without sepsis (sensitivity 27%, specificity 78%). Out of 19 PCR positive subjects, Escherichia coli was detected in 12 infants (63%). Statistically significant association was found between vaginal E. coli colonization of the mother and E. coli PCR positivity of the neonate (p=0.001). No relationship was found between neonatal E. coli swab results and assessment findings of bacterial DNA in neonatal blood stream.

CONCLUSIONS

Multiplex real-time PCR had insufficient diagnostic capability for EOS in high risk very preterm infants. The study revealed no significant association between PCR results and the diagnosis of clinical EOS. Correlation between maternal vaginal swab results and positive PCR in the newborn needs further investigation to fully understand the role of bacterial DNA analysis in preterm infants.

Diagnosis of Neonatal Sepsis: The Role of Inflammatory Markers

This is a narrative review on the role of biomarkers in the diagnosis of neonatal sepsis. We describe the difficulties to obtain standardized definitions in neonatal sepsis and discuss the limitations of published evidence of cut-off values and their sensitivities and specificities. Maternal risk factors influence the results of inflammatory markers as do gestational age, the time of sampling, the use of either cord blood or neonatal peripheral blood, and some non-infectious causes. Current evidence suggests that the use of promising diagnostic markers such as CD11b, CD64, IL-6, IL-8, PCT, and CRP, either alone or in combination, might enable clinicians discontinuing antibiotics confidently within 24-48 h. However, none of the current diagnostic markers is sensitive and specific enough to support the decision of withholding antibiotic treatment without considering clinical findings. It therefore seems to be justified that antibiotics are often initiated in ill term and especially preterm infants. Early markers like IL-6 and later markers like CRP are helpful in the diagnosis of neonatal sepsis considering the clinical aspect of the neonate, the gestational age, maternal risk factors and the time (age of the neonate regarding early-onset sepsis) of blood sampling.

Biomarkers of Neonatal Sepsis: From Being Mere Numbers to Becoming Guiding Diagnostics

Neonatal sepsis is a common cause of neonatal morbidity and mortality. The diagnosis of newborn sepsis is still difficult. Different early objective diagnostic tests or specific signs and symptoms, particularly in preterm infants, make it difficult to diagnose neonatal sepsis. This review article describes biomarkers and their role in the early diagnosis, treatment, and prognosis of neonatal sepsis. It also explores the possible advances and future prospects of these biomarkers. An ideal sepsis biomarker will not only help in the guidance of the use of antibiotics when not needed but also the duration of the course of antibiotics if sepsis is proven. It should also have high sensitivity, specificity, positive predictive value, and negative predictive value. These biomarkers hold a promising position in the management of neonatal sepsis and translate into use in clinical settings. Metabolomics, a diagnostic method based on detecting metabolites found in biological fluids, may open new possibilities in the management of critically ill newborns.

Noninfectious influencers of early-onset sepsis biomarkers

Diagnostic tests for sepsis aim to either detect the infectious agent (such as microbiological cultures) or detect host markers that commonly change in response to an infection (such as C-reactive protein). The latter category of tests has advantages compared to culture-based methods, including a quick turnaround time and in some cases lower requirements for blood samples. They also provide information on the immune response of the host, a critical determinant of clinical outcome. However, they do not always differentiate nonspecific host inflammation from true infection and can inadvertently lead to antibiotic overuse. Multiple noninfectious conditions unique to neonates in the first days after birth can lead to inflammatory marker profiles that mimic those seen among infected infants. Our goal was to review noninfectious conditions and patient characteristics that alter host inflammatory markers commonly used for the diagnosis of early-onset sepsis. Recognizing these conditions can focus the use of biomarkers on patients most likely to benefit while avoiding scenarios that promote false positives. We highlight approaches that may improve biomarker performance and emphasize the need to use patient outcomes, in addition to conventional diagnostic performance analysis, to establish clinical utility.

Reliability of Interleukin-6 Alone and in Combination for Diagnosis of Early Onset Neonatal Sepsis: Systematic Review

Neonatal sepsis is a major cause of morbidity and mortality in both preterm and term infants. Early-onset neonatal sepsis (EONS) presents within the first 72 h of life. Diagnosis is difficult as signs and symptoms are non-specific, and inflammatory markers are widely used to confirm or rule out neonatal sepsis. Interleukin-6 (IL-6) is part of the fetal inflammatory response syndrome (FIRS) and therefore an interesting early marker for neonatal sepsis. The main objective for this review was to assess the diagnostic potential of IL-6, alone and in combination, for diagnosis of early neonatal sepsis (EONS) in term and preterm infants, in cord and peripheral blood, and in dependence of timing of sample collection. IL-6 diagnostic accuracy studies for diagnosing EONS published between 1990 and 2020 were retrieved using the PubMed database. We included 31 out of 204 articles evaluating the potential of IL-6 for the diagnosis of EONS in a study population of newborns with culture-proven and/or clinically suspected sepsis. We excluded articles dealing with neonatal bacterial infections other than sepsis and biomarkers other than inflammatory markers, those written in languages other than English or German, studies that did not distinguish between EONS and late-onset sepsis, and animal and in vitro studies. Full-text articles were checked for other relevant studies according to the PRISMA criteria. We identified 31 studies on IL-6 diagnostic accuracy for EONS diagnosis between 1990 and 2020 including a total of 3,276 infants. Sensitivity and specificity were reported, and subgroup analysis was performed. A STARD checklist adapted for neonates with neonatal sepsis was used for quality assessment. The range of IL-6 sensitivity and specificity in neonatal samples was 42.1-100% and 43-100%; the median values were 83 and 83.3%, respectively. IL-6 accuracy was better in preterm infants than in mixed-study populations. Early sample collection at the time of sepsis suspicion had the highest sensitivity when compared to other time points. Cord blood IL-6 had higher diagnostic value compared to peripheral blood. The biomarker combination of IL-6 and CRP was found to be highly sensitive, but poorly specific. Limitations of this review include use of only one database and inclusion of a heterogeneous group of studies and a small number of studies looking at biomarker combinations; a strength of this review is its focus on early-onset sepsis, since type of sepsis was identified as a significant source of heterogeneity in IL-6 diagnostic accuracy studies. We concluded that IL-6 has a good performance as an early diagnostic marker of EONS within a study population of preterm infants, with best results for cord blood IL-6 using cutoff values above 30 pg/ml.

C-Reactive Protein, Procalcitonin, and White Blood Count to Rule Out Neonatal Early-onset Sepsis Within 36 Hours: A Secondary Analysis of the Neonatal Procalcitonin Intervention Study

BACKGROUND

Neonatal early-onset sepsis (EOS) is one of the main causes of global neonatal mortality and morbidity, and initiation of early antibiotic treatment is key. However, antibiotics may be harmful.

METHODS

We performed a secondary analysis of results from the Neonatal Procalcitonin Intervention Study, a prospective, multicenter, randomized, controlled intervention study. The primary outcome was the diagnostic accuracy of serial measurements of C-reactive protein (CRP), procalcitonin (PCT), and white blood count (WBC) within different time windows to rule out culture-positive EOS (proven sepsis).

RESULTS

We analyzed 1678 neonates with 10 899 biomarker measurements (4654 CRP, 2047 PCT, and 4198 WBC) obtained within the first 48 hours after the start of antibiotic therapy due to suspected EOS. The areas under the curve (AUC) comparing no sepsis vs proven sepsis for maximum values of CRP, PCT, and WBC within 36 hours were 0.986, 0.921, and 0.360, respectively. The AUCs for CRP and PCT increased with extended time frames up to 36 hours, but there was no further difference between start to 36 hours vs start to 48 hours. Cutoff values at 16 mg/L for CRP and 2.8 ng/L for PCT provided a sensitivity of 100% for discriminating no sepsis vs proven sepsis.

CONCLUSIONS

Normal serial CRP and PCT measurements within 36 hours after the start of empiric antibiotic therapy can exclude the presence of neonatal EOS with a high probability. The negative predictive values of CRP and PCT do not increase after 36 hours.

Serum amyloid A - A prime candidate for identification of neonatal sepsis

Neonatal sepsis is common, lethal, and hard to diagnose. In combination with clinical findings and blood culture, biomarkers are crucial to make the correct diagnose. A Swedish national inquiry indicated that neonatologists were not quite satisfied with the available biomarkers. We assessed the kinetics of 15 biomarkers simultaneously: ferritin, fibrinogen, granulocyte colony-stimulating factor (G-CSF), interferon (IFN)-γ, interleukin (IL)-1β, -6, -8, -10, macrophage inflammatory protein (MIP)-1β, procalcitonin, resistin, serum amyloid A (SAA), tumor necrosis factor (TNF)-α, tissue plasminogen activator-3 and visfatin. The goal was to observe how quickly they rise in response to infection, and for how long they remain elevated. From a neonatal intensive care unit, newborns ≥28 weeks gestational age were recruited. Sixty-eight newborns were recruited to the study group (SG), and fifty-one to the control group (CG). The study group subjects were divided into three subgroups depending on clinical findings: confirmed sepsis (CSG), suspected sepsis (SSG) and no sepsis. CSG and SSG were also merged into an entire sepsis group (ESG) for sub-analysis. Blood samples were collected at three time-points; 0 h, 12-24 h and 48-72 h, in order to mimic a "clinical setting". At 0 h, visfatin was elevated in SSG compared to CG; G-CSF, IFN-γ, IL-1β, -8 and - 10 were elevated in SSG and ESG compared to CG, whereas IL-6 and SAA were elevated in all groups compared to CG. At 12-24 h, IL-8 was elevated in ESG compared to CG, visfatin was elevated in ESG and SSG compared to CG, and SAA was elevated in all three groups compared to CG. At 48-72 h, fibrinogen was elevated in ESG compared to CG, IFN-γ and IL-1β were elevated in SSG and ESG compared to CG, whereas IL-8 and SAA were elevated in all three groups compared to CG. A function of time-formula is introduced as a tool for theoretical prediction of biomarker levels at any time-point. We conclude that SAA has the most favorable kinetics regarding diagnosing neonatal sepsis, of the biomarkers studied. It is also readily available methodologically, making it a prime candidate for clinical use.

Procalcitonin in Preterm Neonates: A Different Threshold and Prolonged Interpretation

Objectives: To evaluate the positive threshold of PCT for neonates of <32 weeks of gestation for the diagnosis of early-onset sepsis and to determine if the level of PCT collected within 6 h of life could be used. Design: Retrospective and bicentric study from May 2016 to April 2018. Setting: Two groups were established, neonates evaluated for PCT at birth (CordPCT) and within 6 h of life (delPCT). Patients: Two hundred and sixty neonates of <32 weeks of gestation born in Nice and South Paris (Bicêtre) University Hospitals, had been evaluated for PCT level. Main Outcomes Measures: The value of the PCT positive threshold was determined for the total population and each groups thanks ROC curves. Results: The threshold level of PCT for the total population was 0.98 ng/mL. The threshold value of cordPCT group was 1.00 vs. 0.98 ng/mL for delPCT group. The area under the Receiver Operating Characteristics curve for PCT sampled in delPCT group was significantly higher than in cordPCT group (0.94 compared to 0.75). Conclusions: The threshold level of PCT was higher in this cohort of neonates of <32 weeks of gestation compared to the value generally described for term neonates. The secondary sampling PCT level seems to be usable in screening algorithm for early-onset neonatal sepsis.

Sepsis Biomarkers

Biomarkers have been used in sepsis to assist with the diagnosis of disease as well as determining the severity of disease, that is, prognosis. These biomarkers are based on the presence of discrete molecules within the blood. Unfortunately, in 2020, a single biomarker does not have sufficient sensitivity and specificity to definitively rule in or rule out sepsis. Biomarkers have shown better performance in animal models of disease.

Relevance of Biomarkers Currently in Use or Research for Practical Diagnosis Approach of Neonatal Early-Onset Sepsis

Neonatal early-onset sepsis (EOS) is defined as an invasive infection that occurs in the first 72 h of life. The incidence of EOS varies from 0.5–2% live births in developed countries, up to 9.8% live births in low resource settings, generating a high mortality rate, especially in extremely low birth weight neonates. Clinical signs are nonspecific, leading to a late diagnosis and high mortality. Currently, there are several markers used for sepsis evaluation, such as hematological indices, acute phase reactants, cytokines, which by themselves do not show acceptable sensitivity and specificity for the diagnosis of EOS in neonates. Newer and more selective markers have surfaced recently, such as presepsin and endocan, but they are currently only in the experimental research stages. This comprehensive review article is based on the role of biomarkers currently in use or in the research phase from a basic, translational, and clinical viewpoint that helps us to improve the quality of neonatal early-onset sepsis diagnosis and management.

Procalcitonin Level at 24 Hours of Age May be Predictive for Transient Tachypnea of the Newborn

Objective It is an important problem to differentiate transient tachypnea of the newborn (TTN) from bacterial pneumonia or other conditions in patients admitted to Neonatal Intensive Care Unit. The aim of this study was to evaluate the predictive value of procalcitonin (PCT) for TTN.

Methods A total of 52 infants were contained in the study. The patients were divided into three groups. Group 1 consisted of patients with pronounced grunting at more than 2 hours postnatal age (n = 16). Group 2 consisted of patients whose grunt was reduced or gone at 2 hours postnatal age but in whom tachypnea persisted until 24 hours postnatal age (n = 18). Group 3 consisted of patients with minimal or no respiratory distress at 24 hours postnatal age (n = 18). In all groups, PCT concentrations were determined at birth and 24 hours postnatal age.

Results PCT concentrations at birth were significantly higher in Group 1 than other groups, but there was no difference between Groups 2 and 3. PCT concentrations at 24 hours postnatal age were significantly higher in Groups 1 and 2 than Group 3. No difference was found between Group 1 and Group 2 at 24 hours postnatal age. All PCT concentrations in Group 3 were significantly lower than other groups. PCT thresholds for the diagnosis of TTN were 0.44 ng/mL at birth (sensitivity 58%, specificity 50%) and 5.11 ng/mL at 24 hours postnatal age (sensitivity 79.4%, specificity 89.1%).

Conclusion Serial PCT measurements at birth and postnatal 24 hours may be helpful in differentiating between pneumonia and TTN. Further researches are needed to confirm this initial study.

Neonatal Sepsis

Neonatal sepsis is associated with severe morbidity and mortality in the neonatal period. Clinical manifestations range from subclinical infection to severe local or systemic infection. Neonatal sepsis is divided into three groups as early-onset neonatal sepsis, late-onset neonatal sepsis and very late-onset neonatal sepsis according to the time of the onset. It was observed that the incidence of early-onset neonatal sepsis decreased with intrapartum antibiotic treatment. However, the incidence of late-onset neonatal sepsis has increased with the increase in the survival rate of preterm and very low weight babies. The source of the causative pathogen may be acquisition from the intrauterine origin but may also acquisition from maternal flora, hospital or community. Prematurity, low birth weight, chorioamnionitis, premature prolonged rupture of membranes, resuscitation, low APGAR score, inability to breastfeed, prolonged hospital stay and invasive procedures are among the risk factors. This article reviews current information on the definition, classification, epidemiology, risk factors, pathogenesis, clinical symptoms, diagnostic methods and treatment of neonatal sepsis.

Reference ranges of Presepsin in preterm infants in the first 48 h of life: A multicenter observational study

BACKGROUND AND OBJECTIVES

Despite low incidence of early-onset sepsis, the majority of preterm newborns receive early antibiotic prophylaxis. Our aim was to assess reference ranges of Presepsin during the first 48 h of life in preterm infants and to evaluate the possible influence of neonatal and maternal factors on its values.

METHODS

This observational study consecutively enrolled newborns ≤ 32 weeks of GA at 0-6 h of life. Enrolled infants were sampled for blood culture, complete white blood cell (WBC) count, and P-SEP at 0-6 (T₀) h of life and for P-SEP at 12 ± 3 (T₁), 24 ± 3 (T₂), and 48 ± 6 (T₃) h of life. Cases of EOS were not considered for the statistical analysis.

RESULTS

Data analysis was performed for 183 patients. P-SEP median values were 583 ng/L at T₀ (IQR 405-800 ng/L, 5th and 95th percentiles 204 and 1200 ng/L), 614 ng/L at T₁ (IQR 450-812 ng/L, 5th and 95th percentiles 262 and 1171 ng/L), 604 ng/L at T₂ (IQR 445-825 ng/L, 5th and 95th percentiles 292 and 1302 ng/L) and 513 ng/L at T₃ (IQR 371-734 ng/L, 5th and 95th percentiles 249 and 1278 ng/L). P-SEP values are negatively associated to gestational age (GA) at T₀, T₁, and T₂.

CONCLUSIONS

We determined for the first time the reference ranges of P-SEP during the first 48 h of life in very preterm infants and provided its percentile distribution at T₀, T₁, T₂ and T₃. P-SEP measurement was affected by GA at T₀, T₁, T₂.

Cytokine Expression by Human Macrophage-Like Cells Derived from the Monocytic Cell Line THP-1 Differs Between Treatment With Milk from Preterm- and Term-Delivering Mothers and Pasteurized Donor Milk

Immunomodulatory proteins from human milk may enhance the protection and development of the infant’s gut. This study compared the immunomodulatory effects of treatment with milk from preterm-(PM) and term-delivering (TM) mothers and pasteurized donor milk (DM) on cytokine gene expression in human macrophage-like cells derived from the monocytic cell line THP-1. The gene expression of tumor necrosis factor-α (TNF-α), interleukin (IL)-6, IL-12 (p40), IL-10 and GAPDH in macrophages treated with PM, TM and DM at steady and activated (inflammatory) states were measured using real-time reverse transcription-polymerase chain reaction. TNF-α and IL-6 in macrophages (both states) with DM were higher than PM or TM. IL-10 in steady state macrophages with DM was higher than PM whereas DM increased IL-10 in activated macrophages compared with TM. TM increased IL-6 and IL-12 (p40) in steady state macrophages compared with PM. IL-12 (p40) in activated macrophages with TM was higher than PM. IL-10 in steady state macrophages with TM was higher than PM. These results suggest that DM induces higher gene expression of pro-inflammatory and anti-inflammatory cytokines in macrophages compared with PM or TM. PM reduced gene expression of pro-inflammatory cytokines compared with TM, which may decrease the development of necrotizing enterocolitis and systematic inflammation.

Use of procalcitonin, neopterin, haptoglobin, serum amyloid A and proinflammatory cytokines in diagnosis and prognosis of bovine respiratory disease in feedlot calves under field conditions

Bovine respiratory diseases (BRD) have long been considered a serious problem that causes major economic losses in feedlot calves (FC). This study aimed to determine the diagnostic and prognostic effect of selected biological markers including, procalcitonin (PCT), neopterin (NP), proinflammatory cytokines (IL-1β, IL-8, TNF-α, IF-γ), haptoglobin (HP) and serum amyloid A (SAA) on FC with BRD under field conditions. Sixty-nine FC that were identified to be infected with Mannheimia haemolytica and Histophilus somni and had different clinical respiratory signs (diseased group) were selected for this study. In addition, 20 healthy FC have been selected as a control group. We have detected higher serum levels of PCT, NP, HP, SAA, IL-1β, IL-8, TNF-α and IF-γ in diseased FC group compared with the control group. All tested markers revealed a high level of discrimination between BRD infected FC and healthy ones (AUC > 0.90). Moreover, the obtained data showed a high degree of prognostic accuracy for PCT, NP, IL-8, HP, IF-γ and IL-1β in predicting treatment response of FC with BRD at the selected thresholds (AUC = 0.99, 0.99, 0.97, 0.93, 0.88 and 0.82, respectively). Significant inhibition was observed for the selected biochemical markers in treated FC 7 days post-treatment. In conclusion, this study showed that BRD in FC was associated with significant alterations in serum APPs, proinflammatory cytokines, PCT and NPT levels. Furthermore, it demonstrated that these serum biomarkers are much higher in FC with BRD compared to recovered ones. Our data suggest that the measurement of PCT, NPT, APPs and cytokines together with the clinical examination may be a useful diagnostic and prognostic tool for assessment of FC naturally infected with M. haemolytica and H. somni.

The usefulness of C-reactive protein as a biomarker in predicting neonatal sepsis in a sub-Saharan African region

Objective

The early diagnosis of neonatal sepsis remains a challenge for physicians. The initiation or/and discontinuation of the empirical antibiotic therapy at neonates with sepsis is a dilemma due to the lack of definitive diagnosis and the fear of misdiagnosing a case with its serious outcomes, which can follow up. Therefore, this study aimed to assess the usefulness of C-reactive protein (CRP) as an inflammatory biomarker in the prediction of the neonatal sepsis diagnosis in Butembo, the Democratic Republic of the Congo, in sub-Saharan Africa. Blood culture and quantitative CRP measurements were performed for each neonate. Receiver operating characteristics (ROC) analyses were done in the assessment of CRP accuracy in diagnosing neonatal sepsis.

Results

Of the 228 neonates screened for sepsis, 69 (30.3%) had a positive blood culture. Of the 228 neonates with suspected sepsis, 94 (41.2%) had a positive CRP. Among the 69 cases with positive blood culture, CRP identified 66 cases. The sensitivity, specificity, positive and negative predictive values of CRP were 95.7%, 82.4%, 70.2%, and 97.8%, respectively. The area under the curve (AUC) for the CRP ROC analysis was 0.948. CRP showed its usefulness in the diagnosis of neonatal sepsis.

A Prospective Cohort Study of Factors Associated with Empiric Antibiotic De-escalation in Neonates Suspected with Early Onset Sepsis (EOS)

BACKGROUND

Prolonged empiric antibiotic use, resulting from diagnostic uncertainties, in suspected early onset sepsis (EOS) cases constitutes a significant problem. Unnecessary antibiotic use increases the risk of antibiotic resistance. Furthermore, prolonged antibiotic use increases the risk of mortality and morbidity in neonates. Proactive measures including empiric antibiotic de-escalation are crucial to overcome these problems.

METHODS

This was a prospective cohort study conducted in the neonatal intensive care units of two public hospitals in Malaysia. Neonates with a gestational age greater than 34 weeks who were started on empiric antibiotics within 72 h of life were screened. The data were then stratified according to de-escalation and non-de-escalation practices, where de-escalation practice was defined as narrowing down or discontinuation of empiric antibiotic within 72 h of treatment.

RESULTS

A total of 1045 neonates were screened, and 429 were included. The neonates were then divided based on de-escalation (n = 207) and non-de-escalation (n = 222) practices. Neonates under non-de-escalation practices showed significantly longer durations of antibiotic use compared to those under de-escalation practices (p < 0.05), with no difference in treatment outcomes. Five factors were found to be associated with de-escalation of antibiotics. They are cesarean section delivery, exposure to antenatal steroids, nil history of maternal pyrexia, absence of meconium-stained amniotic fluid, and normal C-reactive protein ≤ 0.5 mg/dL (p < 0.05).

CONCLUSIONS

Empiric antibiotic de-escalation appears feasible as a routine form of treatment for EOS in late preterm and term neonates.

The use of inflammatory markers as a diagnostic and prognostic approach in neonatal calves with septicaemia

The objective of this study was to evaluate the usefulness of inflammatory markers as a diagnostic and prognostic approach in neonatal calves with septicaemia. The study material consisted of 13 neonatal calves with septicaemia (septicaemic calves, SC) and ten healthy neonatal calves (control calves, CC). Blood samples were collected for biochemical, haematological and microbiological analyses. In addition, faecal samples were collected for microbiological and virological analyses. Three of neonatal calves with septicaemia were positive for E. coli (E. coli O157 serotype) by microbiological examination, but all neonatal calves with septicaemia were negative for rota- and coronaviruses. By haematological examination, there were no significant differences between SC and CC for white blood cell (WBC) and neutrophil (NEU) counts (P > 0.05). NEU counts were higher on day 0 than on day 15 in SC (P < 0.05). Red blood cell (RBC) counts and packed cell volume (PCV) values were higher on day 0 in the SC than in the CC (P < 0.05). By biochemical analyses, tumour necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), procalcitonin (PCT), haptoglobin (Hp), and fibrinogen (Fb) concentrations were higher on day 0 in the SC than in the CC (P < 0.05). After treatment (on day 15), the serum IL-6, PCT, Hp, and Fb concentrations were significantly decreased in the SC compared to the CC (P < 0.05). The serum iron (Fe) concentrations were lower on day 0 in the SC than in the CC (P < 0.05), and were higher on day 15 than on day 0 in the SC (P < 0.05). The study revealed that inflammatory markers could be used for determining the diagnosis and prognosis in neonatal calves with septicaemia.

Blood Procalcitonin Levels and Duration of Antibiotics in Neonatal Sepsis

OBJECTIVE

To determine the time to normalization of procalcitonin (PCT) levels and duration of antibiotics in neonatal sepsis.

METHODS

A prospective observational study design was used. The participants included were neonates with sepsis. The primary outcome measure was time to normalization of PCT levels and duration of antibiotics following clinical resolution.

RESULTS

Time to normalization of PCT levels was 9.6 ± 4.2 days in neonates with septic shock, 6.2 ± 2.5 days in neonates without shock, 9.6 ± 3.1 days in neonates with culture-positive sepsis and 6.4 ± 3.1 days in neonates with culture-negative sepsis. Time to normalization of PCT levels according to the stage of systemic inflammatory response syndrome was 5.8 ± 2.8 days in neonates with sepsis, 6.1 ± 3.1 days in those with sepsis syndrome, 6.3 ± 3.3 days in those with early septic shock and 9.4 ± 3.6 days in those with multiorgan dysfunction syndrome. There was no morbidity and mortality in any neonate in the 4-week follow-up.

CONCLUSION

The duration of antibiotics can be determined by observing the time to normalization of PCT following clinical resolution of sepsis.

Procalcitonin versus C-reactive protein: review of kinetics and performance for diagnosis of neonatal sepsis

Procalcitonin (PCT) and C-reactive protein (CRP) are commonly used biomarkers, but their diagnostic advantage for neonatal early-onset (EOS) or late-onset (LOS) sepsis is controversial. In a comprehensive literature review we found significant heterogeneity between studies in sample timing, cut-off values, consideration of blood culture results for sepsis classification, and definition of EOS versus LOS. We identified 39 studies directly comparing PCT with CRP, but only four in very low birth weight (VLBW) neonates. The mean sensitivity for EOS, LOS, and EOS + LOS was 73.6%, 88.9%, and 76.5% for PCT, compared to 65.6%, 77.4%, and 66.4% for CRP, respectively. Mean specificity of PCT and CRP was 82.8% versus 82.7% for EOS, 75.6% versus 81.7% for LOS, and 80.4% versus 91.3% for EOS + LOS. More studies directly comparing both biomarkers for EOS and LOS, especially in extremely and very-low-birth-weight infants, are needed to determine their clinical value for guidance of antibiotic therapy in neonatal sepsis.

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.

Diagnostic Significance of White Blood Cell Count and C-Reactive Protein in Neonatal Sepsis; Asella Referral Hospital, South East Ethiopia

Introduction

Nowadays various biochemical markers, such as C-Reactive Protein (CRP), Procalcitonin and tumor necrosis factor alpha, have been proposed as a potential marker for screening neonatal sepsis. In the current study, we tried to see the diagnostic significance of White Blood Cell (WBC) count and CRP in diagnostic screening of neonatal sepsis.

Methods

A prospective cross-sectional study was conducted from May 2016 to April 2017 in Asella Teaching and Referral Hospital. Data were entered into EPI-INFO version 3.5.1 for cleanup and then exported to SPSS version 17 for further analysis. Sensitivity, specificity, positive predictive value (PPV) and negative predictive values (NPV) were used to assess the accuracy of CRP and WBC count taking blood culture as gold standard.

Results

Data of 303 neonates with clinical sepsis were analyzed. Positive CRP and abnormal WBC were reported in 136(45%) and 99(32.7%) of study subjects respectively. Blood culture turned to be positive in 88(29.4%) of study subjects. The Sensitivity, Specificity, PPV and NPV of WBC count were 59.5 %, 79.6%, 52%, 64.5% respectively while the sensitivity, specificity, PPV and NPV of CRP were 65.6%, 78%, 42% and 91% respectively. By combining both WBC and CRP, the sensitivity, specificity, PPV and NPV improve to 78.5%, 83%, 60% and 93% respectively. CRP positivity rate was comparable across gram positive and gram negative bacteria while high WBC count were more reported among gram positive sepsis than gram negative ( OR 4.8, (95% CI 1.45-15.87, P 0.01).

Conclusion

Based on this study's finding, it can be concluded that CRP alone or in combination with WBC count showed better diagnostic accuracy in neonatal sepsis.

Intrauterine inflammation, infection, or both (Triple I): A new concept for chorioamnionitis

Chorioamnionitis is a common cause of preterm birth and may cause adverse neonatal outcomes, including neurodevelopmental sequelae. Chorioamnionitis has been marked to a heterogeneous setting of conditions characterized by infection or inflammation or both, followed by a great variety in clinical practice for mothers and their newborns. Recently, a descriptive term: "intrauterine inflammation or infection or both" abbreviated as "Triple I" has been proposed by a National Institute of Child Health and Human Development expert panel to replace the term chorioamnionitis. It is particularly important to recognize that an isolated maternal fever does not automatically equate to chorioamnionitis. This article will review the current literature on chorioamnionitis, and introduce the concept of Triple I, as well as recommendations for assessment and management of pregnant women and their newborns with a diagnosis of Triple I.

Presepsin as a predictor of early onset neonatal sepsis in the umbilical cord blood of premature infants with premature rupture of membranes

BACKGROUND

The aim of this study was to investigate whether presepsin level in umbilical cord blood can be used as a predictor of early onset neonatal sepsis (EONS) in preterm labor with premature rupture of membranes (PROM), allowing rational use of antibiotics.

METHODS

All preterm infants between 24 + 0 and 36 + 6 weeks of gestation born to pregnant women with PROM were enrolled in the study. Blood samples were obtained from clamped umbilical cords after delivery of the neonate and prior to the delivery of the placenta for C-reactive protein and presepsin measurement. A diagnosis or suspicion of EONS was based on clinical symptoms or laboratory results in the absence of positive blood culture.

RESULTS

A total of 288 women were included in the study and delivered at 31 + 4 weeks (range, 25-36 + 5 weeks). Microbial invasion of the amniotic cavity was identified in 62 women (81.6%) with EONS and in 31 (14.6%) without (P = 0.004). The prevalence of EONS was 26.4% (76/288). Median umbilical cord presepsin was significantly higher in neonates with EONS than in those without: 2,231 pg/mL (range, 1,442-3,988 pg/mL) versus 275 pg/mL (range, 116-326 pg/mL; P < 0.000). On logistic regression analysis the only independent predictor of EONS was umbilical cord blood presepsin (OR, 12.6; 95% CI: 2.5-28.1, P = 0.000).

CONCLUSIONS

Umbilical cord blood presepsin is a predictor for EONS in preterm infants with PROM and may help to reduce the unnecessary use of antibiotics.

Culture-Negative Early-Onset Neonatal Sepsis - At the Crossroad Between Efficient Sepsis Care and Antimicrobial Stewardship

Sepsis is a leading cause of mortality and morbidity in neonates. Presenting clinical symptoms are unspecific. Sensitivity and positive predictive value of biomarkers at onset of symptoms are suboptimal. Clinical suspicion therefore frequently leads to empirical antibiotic therapy in uninfected infants. The incidence of culture confirmed early-onset sepsis is rather low, around 0.4-0.8/1000 term infants in high-income countries. Six to 16 times more infants receive therapy for culture-negative sepsis in the absence of a positive blood culture. Thus, culture-negative sepsis contributes to high antibiotic consumption in neonatal units. Antibiotics may be life-saving for the few infants who are truly infected. However, overuse of broad-spectrum antibiotics increases colonization with antibiotic resistant bacteria. Antibiotic therapy also induces perturbations of the non-resilient early life microbiota with potentially long lasting negative impact on the individual's own health. Currently there is no uniform consensus definition for neonatal sepsis. This leads to variations in management. Two factors may reduce the number of culture-negative sepsis cases. First, obtaining adequate blood cultures (0.5-1 mL) at symptom onset is mandatory. Unless there is a strong clinical or biochemical indication to prolong antibiotics physician need to trust the culture results and to stop antibiotics for suspected sepsis within 36-48 h. Secondly, an international robust and pragmatic neonatal sepsis definition is urgently needed. Neonatal sepsis is a dynamic condition. Rigorous evaluation of clinical symptoms ("organ dysfunction") over 36-48 h in combination with appropriately selected biomarkers ("dysregulated host response") may be used to support or refute a sepsis diagnosis.

Procalcitonin: The marker of pediatric bacterial infection

Timely recognition of systemic bacterial infections in pediatric care setting is the basis for effective treatment and control. This review provides an overview of procalcitonin (PCT) as an early marker for the detection of severe, invasive bacterial infection in children. Almost all articles on biochemical property and clinical studies in PubMed and Scopus databases regarding their use in pediatric infections and the use of PCT as a marker of bacterial infections were examined. Various methods and analyzers are currently available for the evaluation of PCT. Employment of PCT in the identification of neonatal bacterial infection is a complex process in some conditions. Age specific cut-off, underlying syndrome, and maternal antibiotics usage should be considered when PCT is to be applied in neonates. PCT might be false-negative in these conditions. However, if used appropriately, it can lead to a higher specificity than other immunologic markers. Due to its correlation with the severity of infection, PCT can consequently be used as a prognostic indicator especially for sepsis and urinary tract infection. It is, therefore, a practical supplementary means for the identification of bacterial infections in pediatric health settings.

The role of interleukin-6 in the early diagnosis of sepsis in premature infants

Septicemia is one of the major causes of mortality and morbidity in newborns. The aim of this study was to investigate the role of interleukin-6 (IL-6) in the early diagnosis of Sepsis in premature newborns. This cross-sectional study was conducted on preterm infants admitted to NICU of Hospital Buali in Ardabil city, Iran. C-reactive protein (CRP), IL-6 and complete blood count tests have been done in baseline, third and seventh day. Collected data analyzed by one-sample t-test, repeated measures and ANOVA in SPSS.21. The mean of IL-6 in the first and third day after hospitalization was significantly more than normal value. The mean of CRP in the third and seventh day after hospitalization significantly more than normal value. We found that increasing in IL-6 level can occur earlier than CRP and it can be used as a good index in early sepsis diagnosis compare than CRP.

Diagnostics for neonatal sepsis: current approaches and future directions

Progress has been made in the reduction of morbidity and mortality from neonatal sepsis. However, diagnosis continues to rely primarily on conventional microbiologic techniques, which can be inaccurate. The objective of this review is to provide the clinician with an overview of the current information available on diagnosing this condition. We review currently available diagnostic approaches for documenting neonatal sepsis and also describe novel approaches for diagnosing infection in neonates who are under development and investigation. Substantial progress has been made with molecular approaches and further development of non-culture-based methods offer promise. The potential ability to incorporate antimicrobial resistance gene testing in addition to pathogen identification may provide a venue to incorporate a predominantly molecular platform into a larger program of neonatal care.

Procalcitonin-guided decision making for duration of antibiotic therapy in neonates with suspected early-onset sepsis: a multicentre, randomised controlled trial (NeoPIns)

BACKGROUND

Up to 7% of term and late-preterm neonates in high-income countries receive antibiotics during the first 3 days of life because of suspected early-onset sepsis. The prevalence of culture-proven early-onset sepsis is 0·1% or less in high-income countries, suggesting substantial overtreatment. We assess whether procalcitonin-guided decision making for suspected early-onset sepsis can safely reduce the duration of antibiotic treatment.

METHODS

We did this randomised controlled intervention trial in Dutch (n=11), Swiss (n=4), Canadian (n=2), and Czech (n=1) hospitals. Neonates of gestational age 34 weeks or older, with suspected early-onset sepsis requiring antibiotic treatment were stratified into four risk categories by their treating physicians and randomly assigned [1:1] using a computer-generated list stratified per centre to procalcitonin-guided decision making or standard care-based antibiotic treatment. Neonates who underwent surgery within the first week of life or had major congenital malformations that would have required hospital admission were excluded. Only principal investigators were masked for group assignment. Co-primary outcomes were non-inferiority for re-infection or death in the first month of life (margin 2·0%) and superiority for duration of antibiotic therapy. Intention-to-treat and per-protocol analyses were done. This trial was registered with ClinicalTrials.gov, number NCT00854932.

FINDINGS

Between May 21, 2009, and Feb 14, 2015, we screened 2440 neonates with suspected early-onset sepsis. 622 infants were excluded due to lack of parental consent, 93 were ineligible for reasons unknown (68), congenital malformation (22), or surgery in the first week of life (3). 14 neonates were excluded as 100% data monitoring or retrieval was not feasible, and one neonate was excluded because their procalcitonin measurements could not be taken. 1710 neonates were enrolled and randomly assigned to either procalcitonin-guided therapy (n=866) or standard therapy (n=844). 1408 neonates underwent per-protocol analysis (745 in the procalcitonin group and 663 standard group). For the procalcitonin group, the duration of antibiotic therapy was reduced (intention to treat: 55·1 vs 65·0 h, p<0·0001; per protocol: 51·8 vs 64·0 h; p<0·0001). No sepsis-related deaths occurred, and 9 (<1%) of 1710 neonates had possible re-infection. The risk difference for non-inferiority was 0·1% (95% CI -4·6 to 4·8) in the intention-to-treat analysis (5 [0·6%] of 866 neonates in the procalcitonin group vs 4 [0·5%] of 844 neonates in the standard group) and 0·1% (-5·2 to 5·3) in the per-protocol analysis (5 [0·7%] of 745 neonates in the procalcitonin group vs 4 [0·6%] of 663 neonates in the standard group).

INTERPRETATION

Procalcitonin-guided decision making was superior to standard care in reducing antibiotic therapy in neonates with suspected early-onset sepsis. Non-inferiority for re-infection or death could not be shown due to the low occurrence of re-infections and absence of study-related death.

FUNDING

The Thrasher Foundation, the NutsOhra Foundation, the Sophia Foundation for Scientific research.