Presepsin and fetuin-A dyad for the diagnosis of proven sepsis in preterm neonates

Reliability of IL-6 Alone and in Combination for Diagnosis of Late Onset Sepsis: A Systematic Review

Diagnosis of neonatal sepsis is difficult due to nonspecific signs and symptoms. Interleukin-6 (IL-6) is a promising marker for neonatal sepsis. We aimed to test the accuracy of IL-6 in neonates after 72 h of life in case of late onset sepsis (LOS). We searched for studies regarding IL-6 accuracy for the diagnosis of LOS between 1990 and 2020 using the PubMed database. Following study selection, the reported IL-6 sensitivities and specificities ranged between 68% and 100% and 28% and 100%, with median values of 85.7% and 82% and pooled values of 88% and 78% (respectively) in the 15 studies including 1306 infants. Subgroup analysis revealed a better sensitivity (87% vs. 82%), but not specificity (both 86%), in preterm infants compared to term infants or mixed populations. Early sample collection revealed the highest sensitivity (84%), but had the lowest specificity (86%). To assess quality, we used a STARD checklist adapted for septic neonates and the QUADAS criteria. Limitations of this review include the heterogeneous group of studies on the one side and the small number of studies on the other side that analyzed different combinations of biomarkers. We concluded that IL-6 demonstrated good performance especially in the preterm infant population and the best results were achieved by measurements at the time of LOS suspicion.

Advances of presepsin in sepsis-associated ARDS

This article reviews the correlation between presepsin and sepsis and the resulting acute respiratory distress syndrome (ARDS). ARDS is a severe complication of sepsis. Despite the successful application of protective mechanical ventilation, restrictive fluid therapy, and neuromuscular blockade, which have effectively reduced the morbidity and mortality associated with ARDS, the mortality rate among patients with sepsis-associated ARDS remains notably high. The challenge lies in the prediction of ARDS onset and the timely implementation of intervention strategies. Recent studies have demonstrated significant variations in presepsin (PSEP) levels between patients with sepsis and those without, particularly in the context of ARDS. Moreover, these studies have revealed substantially elevated PSEP levels in patients with sepsis-associated ARDS compared to those with nonsepsis-associated ARDS. Consequently, PSEP emerges as a valuable biomarker for identifying patients with an increased risk of sepsis-associated ARDS and to predict in-hospital mortality.

Proteomic Profiling of Early Secreted Proteins in Response to Lipopolysaccharide-Induced Vascular Endothelial Cell EA.hy926 Injury

Sepsis is a crucial public health problem with a high mortality rate caused by a dysregulated host immune response to infection. Vascular endothelial cell injury is an important hallmark of sepsis, which leads to multiple organ failure and death. Early biomarkers to diagnose sepsis may provide early intervention and reduce risk of death. Damage-associated molecular patterns (DAMPs) are host nuclear or cytoplasmic molecules released from cells following tissue damage. We postulated that DAMPs could potentially be a novel sepsis biomarker. We used an in vitro model to determine suitable protein-DAMPs biomarkers for early sepsis diagnosis. Low and high lipopolysaccharide (LPS) doses were used to stimulate the human umbilical vein endothelial cell line EA.hy926 for 24, 48, and 72 h. Results showed that cell viability was reduced in both dose-dependent and time-dependent manners. Cell injury was corroborated by a significant increase in lactate dehydrogenase (LDH) activity within 24 h in cell-conditioned medium. Secreted protein-DAMPs in the supernatant, collected at different time points within 24 h, were characterized using shotgun proteomics LC-MS/MS analysis. Results showed that there were 2233 proteins. Among these, 181 proteins from the LPS-stimulated EA.hy926 at 1, 12, and 24 h were significantly different from those of the control. Twelve proteins were up-regulated at all three time points. Furthermore, a potential interaction analysis of predominant DAMPs-related proteins using STITCH 5.0 revealed the following associations with pathways: response to stress; bacterium; and LPS (GO:0080134; 0009617; 0032496). Markedly, alpha-2-HS-glycoprotein (AHSG or fetuin-A) and lactotransferrin (LTF) potentially presented since the first hour of LPS stimulation, and were highly up-regulated at 24 h. Taken together, we reported proteomic profiling of vascular endothelial cell-specific DAMPs in response to early an in vitro LPS stimulation, suggesting that these early damage-response protein candidates could be novel early biomarkers associated with sepsis.

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.

Decreased plasma fetuin-A level as a novel bioindicator of poor prognosis in community-acquired pneumonia: A multi-center cohort study

Background

Community-acquired pneumonia (CAP) is a respiratory disease that frequently requires hospital admission, and is a significant cause of death worldwide. Plasma fetuin-A levels were significantly lower in patients with sepsis, but data regarding CAP are scarce. This study aimed to evaluate the usefulness of fetuin-A as a prognostic biomarker of CAP.

Methods

A multicenter cohort study on CAP was conducted between January 2017 and December 2018. Demographic and clinical data were recorded for all enrolled patients. Plasma fetuin-A levels were determined using a quantitative enzyme-linked immunosorbent assay. A Cox proportional hazards regression analysis was used to analyse the effect of variables on 30-day mortality. A logistic regression analysis was performed to assess risk factors associated with severe CAP (SCAP) and 30-day mortality. A receiver operating characteristic (ROC) curve was used to verify the association between variables and CAP prognosis. Correlations were assessed using Spearman's test. Survival curves were constructed and compared using the log-rank test.

Results

A total of 283 patients with CAP were enrolled in this study. Fetuin-A levels were decreased in patients with CAP, especially in SCAP and non-survivors. A cox regression analysis showed that CURB-65 and fetuin-A levels were independent prognostic indicators of 30-day mortality. Via a multiple logistic regression analysis, plasma level of fetuin-A (<202.86 mg/L) was determined to be the strongest independent predictor of 30-day mortality considered (odds ratio, 57.365), and also was also determined to be an independent predictor of SCAP. The area under the curve (AUC) of fetuin-A for predicting 30-day mortality was 0.871, and accuracy was high (P < 0.05). Plasma fetuin-A levels were negatively correlated with WBC, NE%, Glu, CRP, PCT, CURB-65, and pneumonia severity index scores and positively correlated with albumin level. Kaplan–Meier curves showed that lower plasma levels of fetuin-A levels were associated with increased 30-day mortality levels (P < 0.0001).

Conclusion

Plasma fetuin-A levels were decreased in patients with CAP. Fetuin-A can reliably predict mortality in patients with CAP, and is a useful diagnostic indicator of SCAP.

Perinatal presepsin assessment: a new sepsis diagnostic tool?

Perinatal sepsis constitutes a medical emergency and is still one of the major causes of mortality and morbidity. The possibility of an early diagnosis of sepsis is still debated and controversial. In particular, clinical symptoms can be hidden by the association of sepsis with other perinatal diseases and/or by therapeutic strategies performed. In this context, there is evidence that the accuracy of standard of care diagnostic parameters (i.e. blood culture, C-reactive protein, procalcitonin) can be biased by additional confounding factors (gestational age, birth-weight, acute-chronic hypoxia). Therefore, the inclusion in clinical daily practice of new biomarkers of sepsis is of utmost importance. Of a panel of biomarkers, Presepsin (P-SEP) plays an important role in the development and response of the immune system and as an early marker of sepsis both in adult and pediatric patients. Therefore, in the present review we aim to offer an overview of the role of P-SEP in the early detection of perinatal sepsis as a trustworthy marker according to actual statements of official international institutions. Future perspectives regard the possibility of a longitudinal non-invasive biological fluids P-SEP assessment thus limiting the sample stress in high risk newborns.

The Role and Validity of Diagnostic Biomarkers in Late-Onset Neonatal Sepsis

Sepsis remains a leading cause of mortality in the neonatal population, and currently, there is still no consensus on an accurate biomarker that can aid prompt diagnosis. This review focuses on studies investigating biomarkers for late-onset neonatal sepsis specifically. We discuss the current evidence for traditionally used biomarkers and present recent developments on more novel markers.  Suitable articles were selected from PubMed, Embase, Medline, Cochrane Handbook of Systematic Reviews, and ScienceDirect. Inclusion criteria were studies published from 2010 to 2020. Exclusion criteria were animal model-based studies. Keywords in search strategy were late-onset neonatal sepsis + biomarkers + diagnosis.  Evidence is growing increasingly weak for commonly studied biomarkers such as C-reactive protein (CRP) and procalcitonin (PCT). Levels of markers such as Serum Amyloid A and Neutrophil CD64 increase more rapidly post-onset of infection compared to CRP. Moreover, this review found that the more novel biomarkers discussed such as presepsin and endocan may show superior and more promising potential as diagnostic markers. However, larger studies over multicenters are deemed essential to ascertain the ideal biomarker.

Biomarkers as point of care tests (POCT) in neonatal sepsis: A state of science review

Lack of a standard definition of neonatal sepsis and a swift diagnostic method has proven detrimental in the management of this serious condition. Biomarkers have emerged as a beacon that might help us detect neonatal sepsis more effectively. The use of point-of-care biomarkers can aid in early diagnosis and timely initiation of treatment. Procalcitonin, presepsin, interleukin-6, highly specific C-reactive protein, and neutrophil gelatinase-associated lipocalin have been proven to aid in early diagnosis and timely initiation of treatment, thereby reducing sepsis-induced morbidity and mortality. These biomarkers have been found to be useful in reducing the duration of hospital stay and monitoring the response to therapy. When used in combination with each other, or with clinical scores, they have been proven to be advantageous over the gold standard by eliminating the waiting time for blood culture results. The use of biomarkers as a point of care investigation holds a future over the traditional method. We present a state of science review of literature summarizing the current status of these biomarkers in neonatal sepsis.

Biomarkers for Point-of-Care Diagnosis of Sepsis

Sepsis is defined as a life-threatening organ dysfunction caused by a dysregulated host response to infection. In 2017, almost 50 million cases of sepsis were recorded worldwide and 11 million sepsis-related deaths were reported. Therefore, sepsis is the focus of intense research to better understand the complexities of sepsis response, particularly the twin underlying concepts of an initial hyper-immune response and a counter-immunological state of immunosuppression triggered by an invading pathogen. Diagnosis of sepsis remains a significant challenge. Prompt diagnosis is essential so that treatment can be instigated as early as possible to ensure the best outcome, as delay in treatment is associated with higher mortality. In order to address this diagnostic problem, use of a panel of biomarkers has been proposed as, due to the complexity of the sepsis response, no single marker is sufficient. This review provides background on the current understanding of sepsis in terms of its epidemiology, the evolution of the definition of sepsis, pathobiology and diagnosis and management. Candidate biomarkers of interest and how current and developing point-of-care testing approaches could be used to measure such biomarkers is discussed.