Combination of C-reactive protein, procalcitonin and sepsis-related organ failure score for the diagnosis of sepsis in critical patients

Decoy receptor 3 as a prognostic biomarker for sepsis and septic shock according to the Sepsis-3 definitions

Objectives

The present study was conducted to reappraise the prognostic value of decoy receptor 3 (DcR3) for patients with sepsis and septic shock according to the latest Sepsis-3 definitions.

Methods

Subjects suffering from sepsis or septic shock were enrolled within 6 h of admission. The Sequential Organ Failure Assessment (SOFA) score and the plasma levels of DcR3, C-reactive protein, procalcitonin, and interleukin-6 were measured. Group comparisons were made based on the survival status on day 28 after onset. Predictors of mortality were assessed using the Cox proportional hazard models, and survival curves were plotted with the Kaplan-Meier method. Discriminative performances of single and combined indicators were evaluated via the areas under receiver operating characteristic curves.

Results

Among 143 eligible sepsis cases, 77 developed septic shock, and the 28-day mortality rates were 32.2% and 45.5%, respectively. Regardless of the population (all sepsis or septic shock), non-survivors exhibited significantly higher DcR3 levels compared to survivors (median 4.19 vs. 2.64 ng/mL and 4.37 vs. 3.18 ng/mL, respectively; p < 0.001 and p = 0.002, respectively). DcR3 levels were most correlated with organ dysfunction presented by SOFA scores (correlation coefficient = 0.347 and 0.308, respectively; p = 0.001 and 0.016, respectively) but did not differ among the various pathogenic microbes of infection. Multivariate Cox regression identified DcR3 as an independent predictor of mortality [hazard ratio (95% confidence interval): 1.570 (1.048-2.352) and 1.828 (1.047-3.194), respectively; p = 0.029 and 0.034, respectively]. Kaplan-Meier analysis showed that elevated DcR3 concentrations were associated with significantly lower survival rates (p = 0.001 and 0.013, respectively). The areas under receiver operating characteristic curves of DcR3 alone for predicting outcome were superior to that of the other three biomarkers (0.731 and 0.711, respectively) and could be further improved when coupled with SOFA scores (0.803 and 0.784, respectively).

Conclusions

DcR3 is a valuable prognostic biomarker for sepsis and septic shock, offering the potential to predict 28-day mortality in clinical settings.

Thrombocytopenia in Sepsis

Platelets, traditionally known for their role in hemostasis, have emerged as key players in immune response and inflammation. Sepsis, a life-threatening condition characterized by systemic inflammation, often presents with thrombocytopenia, which at times, can be significant. Platelets contribute to the inflammatory response by interacting with leukocytes, endothelial cells, and the innate immune system. However, excessive platelet activation and consumption can lead to thrombocytopenia and exacerbate the severity of sepsis. Understanding the multifaceted roles of platelets in sepsis is crucial for developing effective therapeutic strategies. Targeting platelet-mediated inflammatory responses and promoting platelet production may offer potential avenues for improving outcomes in septic patients with thrombocytopenia. Future research should focus on elucidating the mechanisms underlying platelet dysfunction in sepsis and exploring novel therapeutic approaches to optimize platelet function and mitigate inflammation. This review explores the intricate relationship between platelets, inflammation, and thrombosis in the context of sepsis.

Decoding Inflammation: Predicting Sepsis in the ICU

BACKGROUND

Sepsis is a life-threatening condition arising from a dysregulated host response to infection leading to organ dysfunction. Traditional clinical signs are often unreliable for detecting sepsis, necessitating the exploration of more accurate biomarkers. Furthermore, currently, recommended screening scores perform poorly, necessitating more effective biomarkers to identify sepsis. Therefore, in this study, we evaluated the predictive capabilities of six inflammatory biomarkers - C-reactive protein (CRP), red cell distribution width (RDW), neutrophil-lymphocyte ratio (NLR), monocyte distribution width (MDW), mean neutrophil volume (MNV), and mean monocyte volume (MMV) - measured from samples taken for complete blood count (CBC) for the development of sepsis in ICU patients.

METHODS

We conducted a prospective observational study involving ICU patients at a tertiary-care hospital in Hyderabad, India, over a one-year period to primarily assess the predictability of these six biomarkers for sepsis. As a secondary outcome, we also analyzed the predictiveness of the biomarkers with respect to mortality, the need for vasopressors, invasive mechanical ventilation or renal replacement therapy (RRT), the presence of organ failure, and hospital length of stay. Blood samples were collected for CRP and CBC on the first day of admission, from which RDW, NLR, MDW, MNV, and MMV were measured. Demographic data, including Acute Physiology and Chronic Health Evaluation II (APACHE II) and Sequential Organ Failure Assessment (SOFA) scores, clinical progression (recovery or mortality), requirement for vasopressors, invasive mechanical ventilation, RRT, presence of organ failure, and overall length of hospital stay, were documented.

RESULTS

We analyzed data from 84 patients after one patient withdrew consent. The study sample had a mean age of 65.83 years, with 60 (71.4%) patients >60 years of age and a male predominance (n = 50; 59.5%). About 57 (67.85%) patients had three or more comorbidities. About 71 (84.5%) patients met the sepsis-3 criteria. Mean APACHE II and SOFA scores were 18.73 and 5.36, respectively. Primary outcome analysis showed that CRP and MDW were the most sensitive, with sensitivities of 81.75% and 81.7%, respectively, whereas MDW, MNV, and MMV had the highest specificity at 100% each. Correlation analysis revealed that MDW had the best area under the curve (AUC) of 0.932 in predicting sepsis. Multivariate logistic regression identified both MDW and MMV to have a significant positive correlation in the prediction of sepsis. The overall mortality rate was 9.5%. About 82 (97.6%) patients had organ failure, 35 (41.7%) required vasopressors, 20 (23.8%) required invasive mechanical ventilation, 16 (19%) required RRT, and 59 (70.2%) had a hospital stay exceeding five days, with an average length of hospital stay of eight days. No biomarkers showed strong AUC or specificity compared to the SOFA score (0.710, 94.74% specificity in predicting mortality). However, among the six biomarkers, MDW was the most specific (86.84%). A CRP of >65 mg/L was the best indicator for prolonged hospital stay, vasopressor use, and RRT. An MMV of >179 and MDW of >21.86 U were the most sensitive markers for vasopressor requirements.

CONCLUSION

Our findings suggest that easily accessible biomarkers derived from routine CBC tests, particularly MDW and MMV, may serve as valuable tools for early sepsis diagnosis in resource-limited settings.

Unveiling shared diagnostic biomarkers and molecular mechanisms between T2DM and sepsis: Insights from bioinformatics to experimental assays

Septic patients with T2DM were prone to prolonged recovery and unfavorable prognoses. Thus, this study aimed to pinpoint potential genes related to sepsis with T2DM and develop a predictive model for the disease. The candidate genes were screened using protein-protein interaction networks (PPI) and machine learning algorithms. The nomogram and receiver operating characteristic curve were developed to assess the diagnostic efficiency of the biomarkers. The relationship between sepsis and immune cells was analyzed using the CIBERSORT algorithm. The biomarkers were validated by qPCR and western blotting in basic experiments, and differences in organ damage in mice were studied. Three genes (MMP8, CD177, and S100A12) were identified using PPI and machine learning algorithms, demonstrating strong predictive capabilities. These biomarkers presented significant differences in gene expression patterns between diseased and healthy conditions. Additionally, the expression levels of biomarkers in mouse models and blood samples were consistent with the findings of the bioinformatics analysis. The study elucidated the common molecular mechanisms associated with the pathogenesis of T2DM and sepsis and developed a gene signature-based prediction model for sepsis. These findings provide new targets for the diagnosis and intervention of sepsis complicated with T2DM.

Can We Improve Mortality Prediction in Patients with Sepsis in the Emergency Department?

Background and Objectives: Sepsis represents a global health challenge and requires advanced diagnostic and prognostic approaches due to its elevated rate of morbidity and fatality. Our study aimed to assess the value of a novel set of six biomarkers combined with severity scores in predicting 28 day mortality among patients presenting with sepsis in the Emergency Department (ED). Materials and Methods: This single-center, observational, prospective cohort included sixty-seven consecutive patients with septic shock and sepsis enrolled from November 2020 to December 2022, categorized into survival and non-survival groups based on outcomes. The following were assessed: procalcitonin (PCT), soluble Triggering Receptor Expressed on Myeloid Cells-1 (sTREM-1), the soluble form of the urokinase plasminogen activator receptor (suPAR), high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), and azurocidin 1 (AZU1), alongside clinical scores such as the Quick Sequential Organ Failure Assessment (qSOFA), Systemic Inflammatory Response Syndrome (SIRS), the Sequential Organ Failure Assessment (SOFA), the Acute Physiology and Chronic Health Evaluation II (APACHE II), the Simplified Acute Physiology Score II and III (SAPS II/III), the National Early Warning Score (NEWS), Mortality in Emergency Department Sepsis (MEDS), the Charlson Comorbidity Index (CCI), and the Glasgow Coma Scale (GCS). The ability of each biomarker and clinical score and their combinations to predict 28 day mortality were evaluated. Results: The overall mortality was 49.25%. Mechanical ventilation was associated with a higher mortality rate. The levels of IL-6 were significantly higher in the non-survival group and had higher AUC values compared to the other biomarkers. The GCS, SOFA, APACHEII, and SAPS II/III showed superior predictive ability. Combining IL-6 with suPAR, AZU1, and clinical scores SOFA, APACHE II, and SAPS II enhanced prediction accuracy compared with individual biomarkers. Conclusion: In our study, IL-6 and SAPS II/III were the most accurate predictors of 28 day mortality for sepsis patients in the ED.

Electrochemiluminescence Aptasensor with Dual Signal Amplification by Silica Nanochannel-Based Confinement Effect on Nanocatalyst and Efficient Emitter Enrichment for Highly Sensitive Detection of C-Reactive Protein

The rapid and sensitive detection of the important biomarker C-reactive protein (CRP) is of great significance for monitoring inflammation and tissue damage. In this work, an electrochemiluminescence (ECL) aptasensor was fabricated based on dual signal amplification for the sensitive detection of CRP in serum samples. The sensor was constructed by modifying a silica nanochannel array film (SNF) on a cost-effective indium tin oxide (ITO) electrode using the Stöber solution growth method. Gold nanoparticles (AuNPs) were grown in situ within the nanochannels using a simple electrodeposition method as a nanocatalyst to enhance the active electrode area as well as the ECL signal. The negatively charged nanochannels also significantly enriched the positively charged ECL emitters, further amplifying the signal. The recognition aptamer was covalently immobilized on the outer surface of SNF after modification with epoxy groups, constructing the aptasensor. In the presence of CRP, the formation of complexes on the recognitive interface led to a decrease in the diffusion of ECL emitters and co-reactants to the supporting electrode, resulting in a reduction in the ECL signal. Based on this mechanism, ECL detection of CRP was achieved with a linear range of 10 pg/mL to 1 μg/mL and a low limit of detection (7.4 pg/mL). The ECL aptasensor developed in this study offers advantages such as simple fabrication and high sensitivity, making promising applications in biomarker detection.

Effects of C-reactive protein trajectories of critically ill patients with sepsis on in-hospital mortality rate

Sepsis, a life-threatening condition caused by an inflammatory response to systemic infection, results in a significant social burden and healthcare costs. This study aimed to investigate the relationship between the C-reactive protein (CRP) trajectories of patients with sepsis in the intensive care unit (ICU) and the in-hospital mortality rate. We reviewed 1464 patients with sepsis treated in the ICU of Dongyang People's Hospital from 2010 to 2020 and used latent growth mixture modeling to divide the patients into four classes according to CRP trajectory (intermediate, gradually increasing, persistently high, and persistently low CRP levels). We found that patients with intermediate and persistently high CRP levels had the lowest (18.1%) and highest (32.6%) in-hospital mortality rates, respectively. Multiple logistic regression analysis showed that patients with persistently high (odds ratio [OR] = 2.19, 95% confidence interval [CI] = 1.55-3.11) and persistently low (OR = 1.41, 95% CI = 1.03-1.94) CRP levels had a higher risk of in-hospital mortality than patients with intermediate CRP levels. In conclusion, in-hospital mortality rates among patients with sepsis differ according to the CRP trajectory, with patients with intermediate CRP levels having the lowest mortality rate. Further research on the underlying mechanisms is warranted.

Prognostic value of APTT combined with fibrinogen and creatinine in predicting 28-Day mortality in patients with septic shock caused by acute enteric perforation

BACKGROUND

Septic shock is one of the leading causes of mortality in intensive care units. This retrospective study was carried out to evaluate the association of clinical available factors with 28-day mortality.

PATIENTS AND METHOD

In this observational study, patients with perioperative septic shocks secondary to intra-abdominal infection caused by enteric perforation were included. A total of 328 sepsis patients were admitted to the surgical intensive care units from January 2012 to December 2016. A total of 138 patients met the enrolment criteria and were included in the study. The data of demographic, clinical and laboratory were all recorded.

RESULT

All these 138 patients received abdominal surgery prior to surgical intensive care units caused by acute enteric perforation. These patients were all met the diagnostic criteria of septic shock according to Sepsis-3. Statistical analysis showed that lactic acid, blood platelet, fibrinogen, creatinine and activated partial thromboplastin time were found to be associated with 28-day mortality. A combination of serum activated partial thromboplastin time combined with fibrinogen and creatinine could predict in-hospital 28-day mortality. The area under the curve of serum activated partial thromboplastin time combined with fibrinogen and creatinine is 0.875 (0.806-0.944).

CONCLUSION

In conclusion, this pilot study demonstrated that these factors can predict the prognosis of septic shock caused by enteric perforation. In order to reduce the mortality, surgeons and intensive care units physician may consider these data in perioperative period.

Significance of sTREM-1 and sST2 combined diagnosis for sepsis detection and prognosis prediction

The diagnosis of sepsis still lacks a practical and reliable gold standard. The purpose of this study was to confirm the effect of soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) combined with soluble suppression of tumorigenicity 2 (sST2) in the diagnosis of sepsis through the correlation between sTREM-1, sST2, and sequential organ failure assessment (SOFA) scores. Baseline data of 91 patients with sepsis in the intensive care unit were collected, sTREM-1 and sST2 were detected, and the correlation between markers and SOFA score was analyzed. Besides, the prognostic value of baseline and postadmission indicators for sepsis was analyzed with death as the outcome. The results showed that the expressions of sST2 and sTREM-1 in death group and survival group were higher than those in the survival group (p < 0.05). Correlation analysis showed that sST2, sTREM-1, and the joint diagnosis model had a high correlation with SOFA score (p < 0.05), but poor correlation with Acute Physiology and Chronic Health Evaluation Ⅱ score (p > 0.05). Among them, joint diagnosis model has the highest correlation. Receiver operating characteristic curve analysis showed that combined diagnosis had higher area under curve values. sTREM-1/sST2 can be better used in the diagnosis of sepsis than the single biomarker detection, and the combination of the above two biomarkers has potential application value in the detection and prognosis prediction of sepsis.

The Contribution of Procalcitonin, C-Reactive Protein and Interleukin-6 in the Diagnosis and Prognosis of Surgical Sepsis: An Observational and Statistical Study

Background

Sepsis affects over 30 million people worldwide each year, causing approximately 6 million deaths. Challenges in clinical diagnosis and the need for an early diagnosis to prevent mortality due to sepsis have led to dependence on inflammatory biomarkers like Procalcitonin (PCT), C-reactive protein (CRP), and Interleukin-6 (IL-6).

Objective

This study was performed to observe the contribution of inflammatory biomarkers in the diagnosis and prognosis of patients with surgical sepsis.

Methods

We performed a retrospective observational study in a Clinical Emergency Hospital, which included a number of 125 patients with surgical sepsis admitted between January 2020 and December 2021. The patients were included in the study based on the Sepsis-3 definition. PCT, CRP, IL-6, Sepsis-related Organ Failure Assessment (SOFA) score, Charlson Comorbidity Index (CCI), the time up to surgery, the days of treatment in Intensive Care Unit (ICU) and the total days of hospitalization had been statistically analyzed.

Results

The mean age of all patients was 65.14 years. The mean value in all patients for PCT was 20.08 ng/mL, for CRP was 175.42 mg/l, and for IL-6 was 799.6 pg/mL. The strongest correlation between biomarkers was between CRP and IL-6 (r = 0.425; p < 0.0001). Of all biomarkers, the CRP correlated the strongest with patient outcomes (r = 0.544; p < 0.0001). The area under curve (AUC) for the mean values of the inflammatory biomarkers was calculated and the best diagnostic performance was for CRP with 0.816 (95% CI: 0.744-0.887).

Conclusion

CRP and IL-6 were the most efficient in sepsis diagnosis. The association of PCT, CRP and IL-6 has increased the range of certainty in sepsis diagnosis. CRP was the most efficient biomarker in the prognosis of sepsis.

One biomarker does not fit all: tailoring anti-infective therapy through utilization of procalcitonin and other specific biomarkers

INTRODUCTION

Considering the ongoing increase in antibiotic resistance, the importance of judicious use of antibiotics through reduction of exposure is crucial. Adding procalcitonin (PCT) and other biomarkers to pathogen-specific tests may help to further improve antibiotic therapy algorithms and advance antibiotic stewardship programs to achieve these goals.

AREAS COVERED

In recent years, several trials have investigated the inclusion of biomarkers such as PCT into clinical decision-making algorithms. For adult patients, findings demonstrated improvements in the individualization of antibiotic treatment, particularly for patients with respiratory tract infections and sepsis. While most trials were performed in hospitals with central laboratories, point-of-care testing might further advance the field by providing a cost-effective and rapid diagnostic tool in upcoming years. Furthermore, novel biomarkers including CD-64, presepsin, Pancreatic stone and sTREM-1, have all shown promising results for increased accuracy of sepsis diagnosis. Availability of these markers however is currently still limited and there is insufficient evidence for their routine use in clinical care.

EXPERT OPINION

In addition to new host-response markers, combining such biomarkers with pathogen-directed diagnostics present a promising strategy to increase algorithm accuracy in differentiating between bacterial and viral infections. Recent advances in microbiologic testing using PCR or nucleic amplification tests may further improve the diagnostic yield and promote more targeted pathogen-specific antibiotic therapy.

Bioinformatics Analysis of Gene Expression Profiles for Diagnosing Sepsis and Risk Prediction in Patients with Sepsis

: Although early recognition of sepsis is essential for timely treatment and can improve sepsis outcomes, no marker has demonstrated sufficient discriminatory power to diagnose sepsis. This study aimed to compare gene expression profiles between patients with sepsis and healthy volunteers to determine the accuracy of these profiles in diagnosing sepsis and to predict sepsis outcomes by combining bioinformatics data with molecular experiments and clinical information. We identified 422 differentially expressed genes (DEGs) between the sepsis and control groups, of which 93 immune-related DEGs were considered for further studies due to immune-related pathways being the most highly enriched. Key genes upregulated during sepsis, including S100A8, S100A9, and CR1, are responsible for cell cycle regulation and immune responses. Key downregulated genes, including CD79A, HLA-DQB2, PLD4, and CCR7, are responsible for immune responses. Furthermore, the key upregulated genes showed excellent to fair accuracy in diagnosing sepsis (area under the curve 0.747-0.931) and predicting in-hospital mortality (0.863-0.966) of patients with sepsis. In contrast, the key downregulated genes showed excellent accuracy in predicting mortality of patients with sepsis (0.918-0.961) but failed to effectively diagnosis sepsis.In conclusion, bioinformatics analysis identified key genes that may serve as biomarkers for diagnosing sepsis and predicting outcomes among patients with sepsis.

Combining C-reactive protein and quick sequential organ failure assessment (qSOFA) to improve prognostic accuracy for sepsis and mortality in adult inpatients: A systematic review

Background and Aims

Infections are common in hospitals, and if mismanaged can develop into sepsis, a leading cause of death and disability worldwide. This study aimed to examine whether combining C-reactive protein (CRP) with the quick sequential organ failure assessment (qSOFA) improves its accuracy for predicting mortality and sepsis in adult inpatients.

Methods

PubMed, MEDLINE, EMBASE, Scopus, Web of Science, Science Direct, CINAHL, Open Grey, Grey Literature Report, and the Clinical Trials registry were searched using CRP and qSOFA search terms. Title, abstract, and full-text screening were performed by two independent reviewers using pre-determined eligibility criteria, followed by data extraction and a risk of bias assessment using the Quality Assessment tool for Diagnostic Accuracy Studies 2 (QUADAS-2). Disagreements were settled through discussion and consultation with a third reviewer.

Results

Four retrospective studies with a total of 2070 patients were included in this review. Adding CRP to qSOFA improved the Area Under the Receiver Operating Characteristic Curve up to 9.7% for predicting mortality and by 14.9% for identifying sepsis. The sensitivity and specificity of the combined score for mortality prediction were available in two studies. CRP improved the sensitivity of qSOFA by 43% and 71% while only decreasing the specificity by 12% and 7%, respectively. A meta-analysis was not performed due to study heterogeneity.

Conclusion

This comprehensive review provided initial evidence that combining CRP with qSOFA may improve the accuracy of qSOFA alone in identifying sepsis or patients at risk of dying in hospital. The combined tool demonstrated the potential to improve patient outcomes, with implications for low-resource settings given its simplicity and low-cost.

Whetting the Rapid Diagnostic Tools for Sepsis

How to cite this article: Krishna B. Whetting the Rapid Diagnostic Tools for Sepsis. Indian J Crit Care Med 2023;27(3):159-160.

Combination of Interleukin-6, C-Reactive Protein and Procalcitonin Values as Predictive Index of Sepsis in Course of Fever Episode in Adult Haematological Patients: Observational and Statistical Study

Haematological patients represent a vulnerable population to opportunistic infections, mainly due to the disease itself and chemotherapy-induced neutropenia. The level of immune suppression strongly increases the importance of timely antibiotic treatment in order to prevent sepsis-related mortality. During the initial fever episode, serum biomarkers are usually used to estimate the probability of blood stream infection prior to the results of microbial diagnosis. A new serum biomarker combination study on a febrile haematological population, including C-reactive protein (CRP), interleukin-6 (IL-6) and procalcitonin (PCT), is proposed in order to improve their predictive accuracy. In our prospective study, CRP, IL-6 and PCT were evaluated in 34 immunosuppressed haematological patients immediately after the onset of 51 fever episodes, either during the course of standard chemotherapy or high-dose chemotherapy and autologous stem cell transplant. The fever episodes were divided into documented infections and fever alone. Receiver operating characteristic analysis (ROC) was performed for each biomarker and a combination of all three biomarkers (multiROC) to define a new predictive index. Significant differences were evidenced between the two groups (documented infection and no infection) for both PCT and IL-6 (p = 0.03 and p = 0.035, respectively), but none for CRP (p = 0.1). The composite parameter is more reliable than any single biomarker alone, with an area under the curve (AUC) of 79% and with high sensitivity and specificity. IL-6 gave the closest response compared to the composite index. Composite parameters of serum biomarkers could be used for an early diagnosis of infection at fever onset in haematological patients.

Diagnostic and prognostic value of new bioscore in critically ill septic patients

OBJECTIVE

To evaluate the diagnostic and prognostic value of biomarkers and new bioscore in septic patients in intensive care unit (ICU).

MATERIALS AND METHODS

A study was conducted on septic and non-septic patients in ICU. Diagnostic and prognostic values of C-reactive protein (CRP), procalcitonin (PCT), Sequential Organ Failure Assessments (SOFA) score and new bioscore were analysed statistically.

RESULTS

A total of 226 patients were enrolled in the study. In septic patients, PCT, SOFA and bioscore were found significantly increased (p = .007, p = .001 and p = .001, respectively). The AUC value of bioscore was higher than PCT and SOFA in septic patients. SOFA was found to be more significant prognostic marker than bioscore in predicting 28-day mortality. The prognostic value of bioscore and SOFA was similar for predicting 90-day mortality.

CONCLUSIONS

The new bioscore formed by combination of CRP, PCT and SOFA score may be useful in early diagnosis of sepsis.

Two New Neutrophil Subsets Define a Discriminating Sepsis Signature

Rationale: Sepsis is the leading cause of death in adult ICUs. At present, sepsis diagnosis relies on nonspecific clinical features. It could transform clinical care to have immune-cell biomarkers that could predict sepsis diagnosis and guide treatment. For decades, neutrophil phenotypes have been studied in sepsis, but a diagnostic cell subset has yet to be identified. Objectives: To identify an early, specific immune signature of sepsis severity that does not overlap with other inflammatory biomarkers and that distinguishes patients with sepsis from those with noninfectious inflammatory syndrome. Methods: Mass cytometry combined with computational high-dimensional data analysis was used to measure 42 markers on whole-blood immune cells from patients with sepsis and control subjects and to automatically and comprehensively characterize circulating immune cells, which enables identification of novel, disease-specific cellular signatures. Measurements and Main Results: Unsupervised analysis of high-dimensional mass cytometry data characterized previously unappreciated heterogeneity within the CD64+ immature neutrophils and revealed two new subsets distinguished by CD123 and PD-L1 (programmed death ligand 1) expression. These immature neutrophils exhibited diminished activation and phagocytosis functions. The proportion of CD123-expressing neutrophils correlated with clinical severity. Conclusions: This study showed that these two new neutrophil subsets were specific to sepsis and detectable through routine flow cytometry by using seven markers. The demonstration here that a simple blood test distinguishes sepsis from other inflammatory conditions represents a key biological milestone that can be immediately translated into improvements in patient care.

Lentinan Attenuates Damage of the Small Intestinal Mucosa, Liver, and Lung in Mice with Gut-Origin Sepsis

This study is aimed at exploring the effects of lentinan on small intestinal mucosa as well as lung and liver injury in mice with gut-origin sepsis. Cecal ligation and perforation (CLP) were used to construct a mouse model of gut-origin sepsis. The mice were randomly divided into six groups: sham operation group (sham), gut-origin sepsis model group (CLP), ulinastatin-positive drug control group (UTI), lentinan low concentration group (LTN-L, 5 mg/kg), lentinan medium concentration group (LTN-M, 10 mg/kg), and lentinan high concentration group (LTN-H, 20 mg/kg). H&E staining was used to detect the pathological damage of the small intestine, liver, and lung. The serum of mice in each group was collected to detect the expression changes of inflammatory cytokines, oxidative stress biomarkers, and liver function indexes. In vitro assessment of bacterial translocation was achieved through inoculated culture media. Western blot and RT-qPCR were used to detect the expression of molecules related to the NF-κB signaling pathway in the small intestine tissues of mice. The results showed that compared with the CLP group, the injury degree of the small intestine, liver, and lung in mice with gut-origin sepsis was improved with the increase of lentinan concentration. In addition, TNF-α, IL-1β, IL-6, and HMGB1 were decreased with the increase of lentinan concentration, but the expression of IL-10 was increased. Lentinan could also reduce the expression of oxidative stress injury indexes and liver function indexes and inhibit bacterial translocation to liver and lung tissues. Further mechanism investigation revealed that lentinan downregulated the expression of the NF-κB signaling pathway molecules (NF-κB, TLR4, and Bax) and upregulated the expression of occludin and Bcl-2. In conclusion, lentinan inhibits the activity of the NF-κB signaling pathway, thus attenuating injuries of small intestinal mucosa and liver and lung in mice with gut-origin sepsis and reducing the inflammatory response in the process of sepsis.

C-Reactive protein and SOFA scale: A simple score as early predictor of critical care requirement in patients with COVID-19 pneumonia in Spain

OBJECTIVE

To identify potential markers at admission predicting the need for critical care in patients with COVID-19 pneumonia.

MATERIAL AND METHODS

An approved, observational, retrospective study was conducted between March 15 to April 15, 2020. 150 adult patients aged less than 75 with Charlson comorbidity index ≤6 diagnosed with COVID-19 pneumonia were included. Seventy-five patients were randomly selected from those admitted to the critical care units (critical care group [CG]) and seventy-five hospitalized patients who did not require critical care (non-critical care group [nCG]) represent the control group. One additional cohort of hospitalized patients with COVID-19 were used to validate the score.

MEASUREMENTS AND MAIN RESULTS

Multivariable regression showed increasing odds of in-hospital critical care associated with increased C-reactive protein (CRP) (odds ratio 1.052 [1.009-1.101]; P = 0.0043) and higher Sequential Organ Failure Assessment (SOFA) score (1.968 [1.389-2.590]; P < 0.0001), both at the time of hospital admission. The AUC-ROC for the combined model was 0.83 (0.76-0.90) (vs AUC-ROC SOFA P < 0.05). The AUC-ROC for the validation cohort was 0.89 (0.82-0.95) (P > 0.05 vs AUC-ROC development).

CONCLUSION

Patients COVID-19 presenting at admission SOFA score ≥ 2 combined with CRP ≥ 9.1 mg/mL could be at high risk to require critical care.

Procalcitonin as a biomarker of bacterial infection in critically ill patients admitted with suspected Sepsis in Intensive Care Unit of a tertiary care hospital

OBJECTIVE

To compare the diagnostic accuracy of procalcitonin (PCT), C- reactive protein (CRP), total leukocyte count (TLC) and lactate in critically ill patients admitted with suspicion of sepsis.

METHODS

It was a cross sectional study conducted at the department of Chemical Pathology and Endocrinology AFIP, Rawalpindi, in collaboration with Medical and surgical intensive care units (ICU) of CMH Rawalpindi from January 2019 to December 2019. A total of 126 patients of both genders with age above 18 years and fulfilling the inclusion criteria of systemic inflammatory response syndrome (SIRS) were inducted in the study.

RESULTS

Out of 126 patients 82 (65%) patients have positive blood culture results. Male predominance was noted in patients with positive blood culture. Out of 82 patients with positive blood culture results 69(84%) patients have positive PCT results as well whereas 13(15%) patients with positive blood culture results have negative PCT values. 57(69%) patients had Gram negative bacterial infection and 25(30%) patients had Gram positive bacterial infection. Significant difference was noted between the medians of PCT in blood culture positive and blood culture negative group (p value< 0.05) whereas no significant difference was found between medians of CRP, TLC and lactate between blood culture positive and blood culture negative patients (p value > 0.05). ROC curve analysis of PCT, CRP and TLC were done, keeping blood culture as reference standard, PCT showed largest area under the curve (AUC) and clearly outperformed TLC and CRP. PCT showed AUC of 0.781 as compared to CRP and TLC, which was 0.568 and 0.617 respectively. PCT showed sensitivity of 93.9%, specificity of 47.7%, positive predictive value (PPV) of 77% and negative predictive value (NPV) of 80.8%.

CONCLUSION

Higher NPV makes it a reliable marker for screening out sepsis in suspected cases.

Survival Outcome of Sepsis in Recipients of Solid Organ Transplant

Sepsis is a complex disease stemming from a dysregulated immune response toward an infectious agent. In transplantation, sepsis remains one of the leading causes of morbidity and mortality. Solid organ transplant recipients have impaired adaptive immunity due to immunosuppression required to prevent rejection. Immunosuppression has unintended consequences, such as increasing the risk of infections and sepsis. Due to its high morbidity and mortality, early detection of sepsis is paramount to start aggressive treatment. Several biomarkers or combination of biomarkers of sepsis have emerged in the last decade, but they are not dependable for early diagnosis or for outcome prognosis.

Combined analysis of C-reactive protein in pleural fluid and serum is effective in the differential diagnosis of exudative pleural effusions

Background

Exudative pleural effusion (EPE) is one of the common pleural manifestations of various diseases. Differential diagnosis of EPE is imperative clinically as it identifies different causes of EPE, thereby, enabling effective treatments. Thoracoscopy is a useful tool for differential diagnosis of EPE; however, some patients refuse thoracoscopic examination due to its invasive nature. In addition, the specificity and sensitivity of existing routine tests of EPE are unsatisfactory. Therefore, there is a great need to establish an effective method for the differential diagnosis of EPE.

Methods

This study was a single-institution retrospective analysis of diagnostic efficiency of C-reactive protein (CRP) and procalcitonin (PCT) between March 2018 and September 2018. A total of 87 patients diagnosed with EPE were enrolled. All participants underwent diagnostic thoracentesis. The EPE was examined using biochemical, routine, microbiological, and cytological methods. Pathological cytology detection was necessary for those suspected of malignant PE. Benign PE originates in patients with pneumonia, empyema, and tuberculosis. The levels of CRP and PCT in EPE and serum were measured before treatment. Correlation analysis and receiver-operating characteristic (ROC) curve analysis were conducted to determine the underlying relationship between levels of CRP and PCT, and for differential diagnosis.

Results

The ROC analysis showed that the sensitivity and specificity for the analysis of pleural fluid CRP (p-CRP) were higher (cut-off: 17.55 pg/mL; sensitivity: 75.00%, specificity: 83.90%) than that of serum CRP (s-CRP, cut-off: 23.90 pg/mL; sensitivity: 71.00%, specificity: 80.4%) in the differential diagnosis for EPE. However, the analysis of pleural fluid PCT (p-PCT) and serum PCT (s-PCT) did not demonstrate correlations with EPE. Combined analysis of p-CRP (cut-off: 17.55 mg/dL) with s-CRP (cut-off: 23.9 pg/mL) showed the highest diagnostic accuracy (88.4%) in diagnosing infectious EPE.

Conclusions

The data support the close relationship between combined analysis of p-CRP with s-CRP and effective and accurate differential diagnosis of EPE, due to its higher sensitivity and specificity. However, as a highly sensitive marker for diagnosing bacterial infections, neither s-PCT nor p-PCT, showed correlations with the differential diagnosis of EPE.

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2020 (J-SSCG 2020)

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2020 (J-SSCG 2020), a Japanese-specific set of clinical practice guidelines for sepsis and septic shock created as revised from J-SSCG 2016 jointly by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine, was first released in September 2020 and published in February 2021. An English-language version of these guidelines was created based on the contents of the original Japanese-language version. The purpose of this guideline is to assist medical staff in making appropriate decisions to improve the prognosis of patients undergoing treatment for sepsis and septic shock. We aimed to provide high-quality guidelines that are easy to use and understand for specialists, general clinicians, and multidisciplinary medical professionals. J-SSCG 2016 took up new subjects that were not present in SSCG 2016 (e.g., ICU-acquired weakness [ICU-AW], post-intensive care syndrome [PICS], and body temperature management). The J-SSCG 2020 covered a total of 22 areas with four additional new areas (patient- and family-centered care, sepsis treatment system, neuro-intensive treatment, and stress ulcers). A total of 118 important clinical issues (clinical questions, CQs) were extracted regardless of the presence or absence of evidence. These CQs also include those that have been given particular focus within Japan. This is a large-scale guideline covering multiple fields; thus, in addition to the 25 committee members, we had the participation and support of a total of 226 members who are professionals (physicians, nurses, physiotherapists, clinical engineers, and pharmacists) and medical workers with a history of sepsis or critical illness. The GRADE method was adopted for making recommendations, and the modified Delphi method was used to determine recommendations by voting from all committee members.As a result, 79 GRADE-based recommendations, 5 Good Practice Statements (GPS), 18 expert consensuses, 27 answers to background questions (BQs), and summaries of definitions and diagnosis of sepsis were created as responses to 118 CQs. We also incorporated visual information for each CQ according to the time course of treatment, and we will also distribute this as an app. The J-SSCG 2020 is expected to be widely used as a useful bedside guideline in the field of sepsis treatment both in Japan and overseas involving multiple disciplines.

Assessment of the diagnostic value of CEA, CA125, and CRP and their cut-off point for discrimination of exudative pleural effusions

Pleural effusion is divided into exudative and transudative effusion, and the distinction between exudate and transudate requires multiple investigations of biochemical parameters and their comparison in pleural fluid and serum. This study aimed to assess the diagnostic value of CEA, CA125, and CRP and their cut-off point for discrimination of exudative pleural effusions. This epidemiological and cross-sectional study was performed on 50 patients aged between 18 to 90 years with the diagnosis of exudative pleural effusion referred to Imam Khomeini Hospital in Ahvaz in 2018 and 2019. Demographic and clinical information of patients were collected. The pleural effusion was diagnosed based on physical examination and chest radiography. Pleural effusion was confirmed by thoracentesis. A pleural fluid sample was taken from all patients, and the levels of CEA, CA125, and CRP markers were measured in the pleural fluid. Differentiation of transudate and exudate pleural effusions was performed using Light criteria. The mean CEA and CA125 level of pleural fluid were significantly higher, and the mean CRP level of pleural fluid was significantly lower in patients with malignant diagnoses (P <0.05). Cut-off value with highest sensitivity and specificity in differentiating types of exudative pleural effusions was obtained for CEA tumor marker (greater than 49.8), CA125 tumor marker (greater than 814.02), and CRP marker (less than 7.56). Also, in differentiating types of exudative pleural effusions, CEA tumor marker had sensitivity (89.03%) and specificity (78.42%); CA125 tumor marker had sensitivity (53.18%) and specificity (62.44%), and CRP marker had sensitivity (82.16%), and specificity (89.05%) were. Although the tumor markers had high specificity in the present study, the low sensitivity of some of these tumor markers reduced their diagnostic value. On the other hand, given the numerous advantages of tumor markers, such as low cost and non-invasive, combining them with another can increase the diagnostic value and accuracy.

Changes in plasma HDL and its subcomponents HDL2b and HDL3 regulate inflammatory response by modulating SOCS1 signaling to affect severity degree and prognosis of sepsis

OBJECTIVES

To explore if SOCS1 is regulated by plasma HDL and its subcomponents HDL2b and HDL3 to affect inflammatory reaction then to influence the severity degree and prognosis of sepsis.

METHODS

One hundred sepsis patients in ICU and 85 normal control persons from October 2018 to October 2019 in our hospital were enrolled. Adult male C57BL/6 mice were used to establish sepsis model by CLP method. HDL, CRP, and WBC count of human were measured using an auto-analyzer. Plasma HDL, IL-1β, and TNF-α proteins levels of mice were measured with ELISA. Microfluidic chip was used for plasma HDL2b and HDL3 detections. SOCS1 in liver and spleen of mice were measured by qRT-PCR. The relationship between plasma HDL//HDL2b and inflammatory indices/SOCS1 in liver/spleen was analyzed with spearman correlation coefficient method. The sepsis patients/mice were divided into non-survival and survival groups. The sepsis patients were divided into severe and mild sepsis patients based on the SOFA score or divided into high and low score groups according to the APACHE II score. The sepsis mice were divided into high and low score group based on the modified sepsis severity score criterion.

RESULTS

Plasma HDL and HDL2b levels were significantly declined (P < 0.01), while HDL3 was normal in both sepsis patients and mice (P > 0.05). Plasma HDL and HDL2b were negatively associated with the serum CRP concentration and positively correlated with the prognosis and severity in sepsis patients (P < 0.05). Moreover, the downregulated plasma HDL but not HDL2b was negatively related to increased SOCS1 mRNA levels in liver and spleen of mice, which were positively connected with TNF-α and IL-1β protein levels (P < 0.05).

CONCLUSIONS

Plasma HDL is downregulated in sepsis, which may facilitate inflammatory reaction then activate the SOCS1 signaling to regulate the severity and affect prognosis of sepsis. The decline of plasma HDL2b content could aggravate the severity and poor prognosis of sepsis through facilitating inflammatory reaction. The plasma HDL3 is not involved in sepsis. The more and further explorations may be needed.

Optimal combination of early biomarkers for infection and sepsis diagnosis in the emergency department: The BIPS study

OBJECTIVE

To define the best combination of biomarkers for the diagnosis of infection and sepsis in the emergency room.

METHODS

In this prospective study, consecutive patients with a suspicion of infection in the emergency room were included. Eighteen different biomarkers measured in plasma, and twelve biomarkers measured on monocytes, neutrophils, B and T-lymphocytes were studied and the best combinations determined by a gradient tree boosting approach.

RESULTS

Overall, 291 patients were included and analysed, 148 with bacterial infection, and 47 with viral infection. The best biomarker combination which first allowed the diagnosis of bacterial infection, included HLA-DR (human leukocyte antigen DR) on monocytes, MerTk (Myeloid-epithelial-reproductive tyrosine kinase) on neutrophils and plasma metaloproteinase-8 (MMP8) with an area under the curve (AUC) = 0.94 [95% confidence interval (IC95): 0.91;0.97]. Among patients in whom a bacterial infection was excluded, the combination of CD64 expression, and CD24 on neutrophils and CX3CR1 on monocytes ended to an AUC = 0.98 [0.96;1] to define those with a viral infection.

CONCLUSION

In a convenient cohort of patients admitted with a suspicion of infection, two different combinations of plasma and cell surface biomarkers were performant to identify bacterial and viral infection.

A novel procalcitonin-based score for detecting sepsis among critically ill patients

Background

Procalcitonin (PCT) has been widely investigated as an infection biomarker. The study aimed to prove that serum PCT, combining with other relevant variables, has an even better sepsis-detecting ability in critically ill patients.

Methods

We conducted a retrospective cohort study in a regional teaching hospital enrolling eligible patients admitted to intensive care units (ICU) between July 1, 2016, and December 31, 2016, and followed them until March 31, 2017. The primary outcome measurement was the occurrence of sepsis. We used multivariate logistic regression analysis to determine the independent factors for sepsis and constructed a novel PCT-based score containing these factors. The area under the receiver operating characteristics curve (AUROC) was applied to evaluate sepsis-detecting abilities. Finally, we validated the score using a validation cohort.

Results

A total of 258 critically ill patients (70.9±16.3 years; 55.4% man) were enrolled in the derivation cohort and further subgrouped into the sepsis group (n = 115) and the non-sepsis group (n = 143). By using the multivariate logistic regression analysis, we disclosed five independent factors for detecting sepsis, namely, “serum PCT level,” “albumin level” and “neutrophil-lymphocyte ratio” at ICU admission, along with “diabetes mellitus,” and “with vasopressor.” We subsequently constructed a PCT-based score containing the five weighted factors. The PCT-based score performed well in detecting sepsis with the cut-points of 8 points (AUROC 0.80; 95% confidence interval (CI) 0.74–0.85; sensitivity 0.70; specificity 0.76), which was better than PCT alone, C-reactive protein and infection probability score. The findings were confirmed using an independent validation cohort (n = 72, 69.2±16.7 years, 62.5% men) (cut-point: 8 points; AUROC, 0.79; 95% CI 0.69–0.90; sensitivity 0.64; specificity 0.87).

Conclusions

We proposed a novel PCT-based score that performs better in detecting sepsis than serum PCT levels alone, C-reactive protein, and infection probability score.

C-Reactive protein and SOFA scale: A simple score as early predictor of critical care requirement in patients with COVID-19 pneumonia in Spain

OBJECTIVE

To identify potential markers at admission predicting the need for critical care in patients with COVID-19 pneumonia.

MATERIAL AND METHODS

An approved, observational, retrospective study was conducted between March 15 to April 15, 2020. 150 adult patients aged less than 75 with Charlson comorbidity index ≤6 diagnosed with COVID-19 pneumonia were included. Seventy-five patients were randomly selected from those admitted to the critical care units (critical care group [CG]) and seventy-five hospitalized patients who did not require critical care (non-critical care group [nCG]) represent the control group. One additional cohort of hospitalized patients with COVID-19 were used to validate the score.

MEASUREMENTS AND MAIN RESULTS

Multivariable regression showed increasing odds of in-hospital critical care associated with increased C-reactive protein (CRP) (odds ratio 1.052 [1.009-1.101]; P=.0043) and higher Sequential Organ Failure Assessment (SOFA) score (1.968 [1.389-2.590]; P<.0001), both at the time of hospital admission. The AUC-ROC for the combined model was 0.83 (0.76-0.90) (vs AUC-ROC SOFA P<.05). The AUC-ROC for the validation cohort was 0.89 (0.82-0.95) (P>0.05 vs AUC-ROC development).

CONCLUSION

Patients COVID-19 presenting at admission SOFA score ≥2 combined with CRP ≥9,1mg/mL could be at high risk to require critical care.

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2020 (J-SSCG 2020)

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2020 (J-SSCG 2020), a Japanese-specific set of clinical practice guidelines for sepsis and septic shock created as revised from J-SSCG 2016 jointly by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine, was first released in September 2020 and published in February 2021. An English-language version of these guidelines was created based on the contents of the original Japanese-language version. The purpose of this guideline is to assist medical staff in making appropriate decisions to improve the prognosis of patients undergoing treatment for sepsis and septic shock. We aimed to provide high-quality guidelines that are easy to use and understand for specialists, general clinicians, and multidisciplinary medical professionals. J-SSCG 2016 took up new subjects that were not present in SSCG 2016 (e.g., ICU-acquired weakness [ICU-AW], post-intensive care syndrome [PICS], and body temperature management). The J-SSCG 2020 covered a total of 22 areas with four additional new areas (patient- and family-centered care, sepsis treatment system, neuro-intensive treatment, and stress ulcers). A total of 118 important clinical issues (clinical questions, CQs) were extracted regardless of the presence or absence of evidence. These CQs also include those that have been given particular focus within Japan. This is a large-scale guideline covering multiple fields; thus, in addition to the 25 committee members, we had the participation and support of a total of 226 members who are professionals (physicians, nurses, physiotherapists, clinical engineers, and pharmacists) and medical workers with a history of sepsis or critical illness. The GRADE method was adopted for making recommendations, and the modified Delphi method was used to determine recommendations by voting from all committee members. As a result, 79 GRADE-based recommendations, 5 Good Practice Statements (GPS), 18 expert consensuses, 27 answers to background questions (BQs), and summaries of definitions and diagnosis of sepsis were created as responses to 118 CQs. We also incorporated visual information for each CQ according to the time course of treatment, and we will also distribute this as an app. The J-SSCG 2020 is expected to be widely used as a useful bedside guideline in the field of sepsis treatment both in Japan and overseas involving multiple disciplines.

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.

Current Evidence and Limitation of Biomarkers for Detecting Sepsis and Systemic Infection

Sepsis was recently redefined as a life-threatening disease involving organ dysfunction caused by a dysregulated host response to infection. Biomarkers play an important role in early detection, diagnosis, and prognostication. We reviewed six promising biomarkers for detecting sepsis and systemic infection, including C-reactive protein (CRP), procalcitonin (PCT), interleukin-6 (IL-6), CD64, presepsin, and sTREM-1. Among the recent studies, we found the following risks of bias: only a few studies adopted the random or consecutive sampling strategy; extensive case-control analysis, which worsened the over-estimated performance; most of the studies used post hoc cutoff values; and heterogeneity with respect to the inclusion criteria, small sample sizes, and different quantitative synthesis methods applied in meta-analyses. We recommend that CD64 and presepsin should be considered as the most promising biomarkers for diagnosing sepsis. Future studies should enroll a larger sample size with a cohort rather than a case-control study design. A random or consecutive study design with a pre-specified laboratory threshold, consistent sampling timing, and an updated definition of sepsis will also increase the reliability of the studies. Further investigations of appropriate specimens, testing assays, and cutoff levels for specific biomarkers are also warranted.

Duplex Shiny app quantification of the sepsis biomarkers C-reactive protein and interleukin-6 in a fast quantum dot labeled lateral flow assay

Fast point-of-care (POC) diagnostics represent an unmet medical need and include applications such as lateral flow assays (LFAs) for the diagnosis of sepsis and consequences of cytokine storms and for the treatment of COVID-19 and other systemic, inflammatory events not caused by infection. Because of the complex pathophysiology of sepsis, multiple biomarkers must be analyzed to compensate for the low sensitivity and specificity of single biomarker targets. Conventional LFAs, such as gold nanoparticle dyed assays, are limited to approximately five targets-the maximum number of test lines on an assay. To increase the information obtainable from each test line, we combined green and red emitting quantum dots (QDs) as labels for C-reactive protein (CRP) and interleukin-6 (IL-6) antibodies in an optical duplex immunoassay. CdSe-QDs with sharp and tunable emission bands were used to simultaneously quantify CRP and IL-6 in a single test line, by using a single UV-light source and two suitable emission filters for readout through a widely available BioImager device. For image and data processing, a customized software tool, the MultiFlow-Shiny app was used to accelerate and simplify the readout process. The app software provides advanced tools for image processing, including assisted extraction of line intensities, advanced background correction and an easy workflow for creation and handling of experimental data in quantitative LFAs. The results generated with our MultiFlow-Shiny app were superior to those generated with the popular software ImageJ and resulted in lower detection limits. Our assay is applicable for detecting clinically relevant ranges of both target proteins and therefore may serve as a powerful tool for POC diagnosis of inflammation and infectious events.

The plasma peptides of sepsis

Background

A practical strategy to discover sepsis specific proteins may be to compare the plasma peptides and proteins from patients in the intensive care unit with and without sepsis. The aim was to discover proteins and/or peptides that show greater observation frequency and/or precursor intensity in sepsis. The endogenous tryptic peptides of ICU-Sepsis were compared to ICU Control, ovarian cancer, breast cancer, female normal, sepsis, heart attack, Alzheimer’s and multiple sclerosis along with their institution-matched controls, female normals and normal samples collected directly onto ice.

Methods

Endogenous tryptic peptides were extracted from individual sepsis and control EDTA plasma samples in a step gradient of acetonitrile for random and independent sampling by LC–ESI–MS/MS with a set of robust and sensitive linear quadrupole ion traps. The MS/MS spectra were fit to fully tryptic peptides within proteins using the X!TANDEM algorithm. The protein observation frequency was counted using the SEQUEST algorithm after selecting the single best charge state and peptide sequence for each MS/MS spectra. The protein observation frequency of ICU-sepsis versus ICU Control was subsequently tested by Chi square analysis. The average protein or peptide log₁₀ precursor intensity was compared across disease and control treatments by ANOVA in the R statistical system.

Results

Peptides and/or phosphopeptides of common plasma proteins such as ITIH3, SAA2, SAA1, and FN1 showed increased observation frequency by Chi square (χ² > 9, p < 0.003) and/or precursor intensity in sepsis. Cellular gene symbols with large Chi square values from tryptic peptides included POTEB, CTNNA1, U2SURP, KIF24, NLGN2, KSR1, GTF2H1, KIT, RPS6KL1, VAV2, HSPA7, SMC2, TCEB3B, ZNF300, SUPV3L1, ADAMTS20, LAMB4, MCCC1, SUPT6H, SCN9A, SBNO1, EPHA1, ABLIM2, cB5E3.2, EPHA10, GRIN2B, HIVEP2, CCL16, TKT, LRP2 and TMF1 amongst others showed increased observation frequency. Similarly, increased frequency of tryptic phosphopeptides were observed from POM121C, SCN8A, TMED8, NSUN7, SLX4, MADD, DNLZ, PDE3B, UTY, DEPDC7, MTX1, MYO1E, RXRB, SYDE1, FN1, PUS7L, FYCO1, USP26, ACAP2, AHI1, KSR2, LMAN1, ZNF280D and SLC8A2 amongst others. Increases in mean precursor intensity in peptides from common plasma proteins such as ITIH3, SAA2, SAA1, and FN1 as well as cellular proteins such as COL24A1, POTEB, KANK1, SDCBP2, DNAH11, ADAMTS7, MLLT1, TTC21A, TSHR, SLX4, MTCH1, and PUS7L among others were associated with sepsis. The processing of SAA1 included the cleavage of the terminal peptide D/PNHFRPAGLPEKY from the most hydrophilic point of SAA1 on the COOH side of the cystatin C binding that was most apparent in ICU-Sepsis patients compared to all other diseases and controls. Additional cleavage of SAA1 on the NH2 terminus side of the cystatin binding site were observed in ICU-Sepsis. Thus there was disease associated variation in the processing of SAA1 in ICU-Sepsis versus ICU controls or other diseases and controls.

Conclusion

Specific proteins and peptides that vary between diseases might be discovered by the random and independent sampling of multiple disease and control plasma from different hospital and clinics by LC–ESI–MS/MS for storage in a relational SQL Server database and analysis with the R statistical system that will be a powerful tool for clinical research. The processing of SAA1 may play an unappreciated role in the inflammatory response to Sepsis.

Association of Plasma Level of TNF-Related Apoptosis-Inducing Ligand with Severity and Outcome of Sepsis

Recent studies have suggested that TNF-related apoptosis-inducing ligand (TRAIL) is associated with mortality in sepsis, possibly through necroptosis. The objective of this study was to analyze the association between the plasma level of TRAIL and sepsis severity and outcomes. Furthermore, the plasma level of TRAIL was compared to that of receptor-interacting protein kinase-3 (RIPK3), a key executor of necroptosis, to identify any correlation between TRAIL and necroptosis. Plasma levels of TRAIL and RIPK3 from consecutively enrolled critically ill patients were measured by ELISA. Of 190 study patients, 59 (31.1%) and 84 (44.2%) patients were diagnosed with sepsis and septic shock, respectively. There was a trend of decreased plasma level of TRAIL across the control, sepsis, and septic shock groups. For 143 patients with sepsis, patients with low plasma TRAIL were more likely to have septic shock and higher SAPS3 and SOFA scores. However, no difference in 28-day and 90-day mortalities was observed between the two groups. The plasma level of TRAIL was inversely associated with RIPK3 in patients with sepsis. Plasma levels of TRAIL increased over time on days three and seven, and were inversely associated with sepsis severity and RIPK3 level, but not with mortality.

A 2020 review on the role of procalcitonin in different clinical settings: an update conducted with the tools of the Evidence Based Laboratory Medicine

Biomarkers to guide antibiotic treatment decisions have been proposed as an effective way to enhancing a more appropriate use of antibiotics. As a biomarker, procalcitonin (PCT) has been found to have good specificity to distinguish bacterial from non-bacterial inflammations. Decisions regarding antibiotic use in an individual patient are complex and should be based on the pre-test probability for bacterial infection, the severity of presentation and the results of PCT serum concentration. In the context of a high pre-test probability for bacterial infections and/or a high-risk patient with sepsis, monitoring of PCT over time helps to track the resolution of infection and decisions regarding early stop of antibiotic treatment. As outlined by the Evidence Based Laboratory Medicine (EBLM), not only the pre-test probability but also the positive likelihood ratio influence the performance of a test do be really diagnostic. This aspect should be taken into account in the interpretation of the results of clinical trials evaluating the performance of PCT in guiding antibiotic therapy.

Risk factors and outcomes of sepsis-associated delirium in intensive care unit patients: A secondary data analysis

OBJECTIVE

To identify the risk factors of sepsis-associated delirium and determine their effect on intensive care unit adult patient outcomes.

DESIGN

A secondary analysis of data from system development studies.

SETTING

Korean intensive care unit patients in a university hospital who were diagnosed with sepsis.

METHODS

The risk factors for sepsis-associated delirium were classified into patient factors and sepsis clinical features and were analysed using hierarchical logistic regression analysis. Outcomes included in-hospital mortality, 30-day in-hospital mortality, duration of mechanical ventilation, length of stay in the intensive care unit, length of hospital stay, total medical expenses, discharge placement, re-hospitalisation and visits to the emergency department after discharge.

RESULTS

The risk factor for sepsis-associated delirium including patients aged 65 ≥years, dependent activity and high nursing needs (patient factors), low level of consciousness, tachypnoea, and thrombocytopaenia (clinical features of sepsis). Use of vasopressors/inotropes and albumin decreased the risk of sepsis-associated delirium. Mechanical ventilation duration was prolonged and discharge to skilled nursing facilities was increased by sepsis-associated delirium.

CONCLUSIONS

The risk factors for sepsis-associated delirium increased as the severity of condition for patients with sepsis increased. Early identification of risk factors associated with sepsis-associated delirium may improve patient outcomes.

Inflammatory biomarkers to predict adverse outcomes in postoperative patients with acute type A aortic dissection

Objectives. The present study aimed to evaluate prognostic value of inflammatory markers for in-hospital mortality and renal complication in patients undergoing surgery for acute type A aortic dissection (ATAAD). Design. Serum concentration of C-reactive protein, leukocyte counts, procalcitonin (PCT), tumor necrosis factor (TNF)-α, interleukin-2 receptor (IL-2R), IL-6 and IL-8 were measured on the day of admission to the hospital (T0) and on 1st (T1), 2nd (T2), and 7th (T3) day after surgery. Results. 328 patients were included. There were significant differences between survivor group and non-survivor group in PCT, IL-2R, and IL-6 (p = .001, p = .015, and p = .005). There were significant differences between patients with different AKI stage in PCT and IL-2R (p = .001, p < .001). The area under receiver operating characteristics (ROC) curve on 30-day death was 0.686 for PCT, 0.718 for IL-2R, 0.694 for IL-6 and 0.627 for IL-8. The area under ROC curve on stage III AKI was 0.852 for PCT, 0.749 for IL-2R, 0.626 for IL-8, and 0.636 for TNF-α. IL-2 > 1438 U/ml and IL-6 > 45.5 pg/ml were independently associated with 30-day mortality (p = .014 and p < .001). The area under ROC curve was 0.849 on score 2 (using 1 point for PCT > 4.58 ng/ml, 1 point for IL-2R > 1438 U/ml, 1 point for APACHE II score >15.5, and 1 point for IL-6 > 45.5 pg/ml). Conclusions. PCT and cytokines may be considered as predictors for adverse renal outcomes and mortality in patients with ATAAD patients after surgery. They are earlier than traditional biomarkers and combination of these biomarkers will improve the accuracy.

Determination of Melatonin Deprivation Impact on Sepsis With Acute Phase Reactants

BACKGROUND

The aim of the present study is to determine the association of melatonin hormone level on CRP, Total Antioxidant Status, Leukocyte, Procalcitonin, and Malondialdehyde, all acute phase reactants in the dark and light cycle of rats with sepsis model.

MATERIALS AND METHODS

In this study, 54 rats were divided into three groups. Whereas the first and third groups had a 12 h dark-light cycle, the second group was exposed to light for 24 h at 21°C-22°C for 10 d without any water and food restrictions. In the second and third groups, sepsis model was formed by cecal ligation and puncture (CLP) method at the end of 10th day, and blood samples were taken at the end of the 10th day. C-reactive protein, Malondialdehyde, Procalcitonin in the blood samples were analyzed by ELISA, and the levels of Total Antioxidant Status and leukocyte were determined by colorimetric method in the subsequent 12 and 24 h.

RESULTS

CRP values increased in the second group rats, which were kept continuously under light and had undergone CLP, from 288.8 mg/L to 584.0 mg/L at the end of the 12 h and the end of the 24 h, approximately, two times. In rats, which were kept under 12 h of light, 12 h of darkness, and applied CLP (group 3), these values increased from 416.9 to 619.1; an increase of 1.5 times. When assessed for MDA, it was determined that the differences between Group 2 and Group 3 were more prominent between 0 h and 12 h. While the MDA values in group 2 increased from 16.53 nmol/mL at the 12 h to 17.66 nmol/mL at the 24 h. However, MDA values did not yield statistically significant changes in the third group. Changes in the in PCT values were similar to the MDA values obtained. Increase coefficient of the PCT values between 0 h and 12 h in the second group 2 was 1.26; however, in the third group, it was negligible.

CONCLUSIONS

An increase in the oxidative stress was observed in the rats that underwent CLP and melatonin deprivation via continuous 24 h light exposure for 10 d. Accordingly, deprivation of light is considered to be effective in sepsis treatment due to the increase in melatonin levels in intensive care unit patients.

Plasma interleukin-6 concentration for the diagnosis of sepsis in critically ill adults

BACKGROUND

The definition of sepsis has evolved over time, along with the clinical and scientific knowledge behind it. For years, sepsis was defined as a systemic inflammatory response syndrome (SIRS) in the presence of a documented or suspected infection. At present, sepsis is defined as a life-threatening organ dysfunction resulting from a dysregulated host response to infection. Even though sepsis is one of the leading causes of mortality in critically ill patients, and the World Health Organization (WHO) recognizes it as a healthcare priority, it still lacks an accurate diagnostic test. Determining the accuracy of interleukin-6 (IL-6) concentrations in plasma, which is proposed as a new biomarker for the diagnosis of sepsis, might be helpful to provide adequate and timely management of critically ill patients, and thus reduce the morbidity and mortality associated with this condition.

OBJECTIVES

To determine the diagnostic accuracy of plasma interleukin-6 (IL-6) concentration for the diagnosis of bacterial sepsis in critically ill adults.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, LILACS, and Web of Science on 25 January 2019. We screened references in the included studies to identify additional studies. We did not apply any language restriction to the electronic searches.

SELECTION CRITERIA

We included diagnostic accuracy studies enrolling critically ill adults aged 18 years or older under suspicion of sepsis during their hospitalization, where IL-6 concentrations were evaluated by serological measurement.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the references to identify relevant studies and extracted data. We assessed the methodological quality of studies using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. We estimated a summary receiver operating characteristic (SROC) curve by fitting a hierarchical summary ROC (HSROC) non-linear mixed model. We explored sources of heterogeneity using the HSROC model parameters. We conducted all analyses in the SAS statistical software package and R software.

MAIN RESULTS

We included 23 studies (n = 4192) assessing the accuracy of IL-6 for the diagnosis of sepsis in critically ill adults. Twenty studies that were available as conference proceedings only are awaiting classification. The included participants were heterogeneous in terms of their distribution of age, gender, main diagnosis, setting, country, positivity threshold, sepsis criteria, year of publication, and origin of infection, among other factors. Prevalence of sepsis greatly varied across studies, ranging from 12% to 78%. We considered all studies to be at high risk of bias due to issues related to the index test domain in QUADAS-2. The SROC curve showed a great dispersion in individual studies accuracy estimates (21 studies, 3650 adult patients), therefore the considerable heterogeneity in the collected data prevented us from calculating formal accuracy estimates. Using a fixed prevalence of sepsis of 50% and a fixed specificity of 74%, we found a sensitivity of 66% (95% confidence interval 60 to 72). If we test a cohort 1000 adult patients under suspicion of sepsis with IL-6, we will find that 330 patients would receive appropriate and timely antibiotic therapy, while 130 patients would be wrongly considered to have sepsis. In addition, 370 out of 1000 patients would avoid unnecessary antibiotic therapy, and 170 patients would have been undiagnosed of sepsis. This numerical approach should be interpreted with caution due to the limitations described above.

AUTHORS' CONCLUSIONS

Our evidence assessment of plasma interleukin-6 concentrations for the diagnosis of sepsis in critically ill adults reveals several limitations. High heterogeneity of collected evidence regarding the main diagnosis, setting, country, positivity threshold, sepsis criteria, year of publication, and the origin of infection, among other factors, along with the potential number of misclassifications, remain significant constraints for its implementation. The 20 conference proceedings assessed as studies awaiting classification may alter the conclusions of the review once they are fully published and evaluated. Further studies about the accuracy of interleukin-6 for the diagnosis of sepsis in adults that apply rigorous methodology for conducting diagnostic test accuracy studies are needed. The conclusions of the review will likely change once the 20 studies pending publication are fully published and included.

Biomarkers in Pneumonia-Beyond Procalcitonin

Pneumonia is the leading infectious cause of mortality worldwide and one of the most common lower respiratory tract infections that is contributing significantly to the burden of antibiotic consumption. Due to the complexity of its pathophysiology, it is widely accepted that clinical diagnosis and prognosis are inadequate for the accurate assessment of the severity of the disease. The most challenging task for a physician is the risk stratification of patients with community-acquired pneumonia. Herein, early diagnosis is essential in order to reduce hospitalization and mortality. Procalcitonin and C-reactive protein remain the most widely used biomarkers, while interleukin 6 has been of particular interest in the literature. However, none of them appear to be ideal, and the search for novel biomarkers that will most sufficiently predict the severity and treatment response in pneumonia has lately intensified. Although our insight has significantly increased over the last years, a translational approach with the application of genomics, metabolomics, microbiomics, and proteomics is required to better understand the disease. In this review, we discuss this rapidly evolving area and summarize the application of novel biomarkers that appear to be promising for the accurate diagnosis and risk stratification of pneumonia.

Diagnostic value of procalcitonin and presepsin for sepsis in critically ill adult patients: a systematic review and meta-analysis

Background

Early and accurate diagnosis of sepsis is challenging. Although procalcitonin and presepsin have been identified as potential biomarkers to differentiate between sepsis and other non-infectious causes of systemic inflammation, the diagnostic accuracy of these biomarkers remains controversial. Herein, we performed a comprehensive meta-analysis to assess the overall diagnostic value of procalcitonin and presepsin for the diagnosis of sepsis.

Methods

We searched three electronic databases (MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials) for relevant studies. Two authors independently screened articles on the basis of inclusion and exclusion criteria. The pooled sensitivity, specificity, and summary receiver operating characteristic curves were estimated. The quality of evidence for diagnostic accuracy in absolute effects, i.e., the number of true or false positives and true or false negatives, gave a particular pre-test probability.

Results

We included 19 studies (19 observational studies and no randomized controlled trials) that had enrolled 3012 patients. Analyses of summary receiver operating characteristic curves revealed areas under the receiver operating characteristic curves of 0.84 for procalcitonin and 0.87 for presepsin. The pooled sensitivities and specificities were 0.80 (95% confidence interval 0.75 to 0.84) and 0.75 (95% confidence interval 0.67 to 0.81) for procalcitonin. For presepsin, these values were 0.84 (95% confidence interval 0.80 to 0.88) and 0.73 (95% confidence interval 0.61 to 0.82), respectively. There were no statistically significant differences in both pooled sensitivities (p = 0.48) and specificities (p = 0.57) between procalcitonin and presepsin.

Conclusion

Our meta-analysis provided evidence that the diagnostic accuracy of procalcitonin and presepsin in detecting infection was similar and that both are useful for early diagnosis of sepsis and subsequent reduction of mortality in critically ill adult patients.

Systematic review registration

The study was registered in PROSPERO under the registration number CRD42016035784.

Electronic supplementary material

The online version of this article (10.1186/s40560-019-0374-4) contains supplementary material, which is available to authorized users.

Early Blood Biomarkers to Improve Sepsis/Bacteremia Diagnostics in Pediatric Emergency Settings

Background: Sepsis is the leading cause of death in children worldwide. Early recognition and treatment are essential for preventing progression to lethal outcomes. CRP and Complete Blood Count (CBC) are the initial preferred tests to distinguish between bacterial and viral infections. Specific early diagnostic markers are still missing. Aim: To investigate diagnostic value of Neutrophil-Lymphocyte Ratio (NLR), Mean Platelet Volume (MPV) and Platelet-MPV ratio (PLT/MPV) to distinguish sepsis/bacteremia and viral infection. Methods: We conducted a retrospective data analysis of case records of 115 children from 1 month to 5 years of age. All cases were divided into two groups-sepsis/bacteremia (n = 68) and viral (n = 47) patients, and further subdivided according to the time of arrival into early or late (≤12 or 12-48 h post the onset of fever, respectively). Analysis of CBC and CRP results was performed. NLR and PLT/MPV were calculated. Results: Sepsis/bacteremia group demonstrated higher absolute platelets count (370.15 ± 134.65 × 10⁸/L versus 288.91 ± 107.14 × 10⁸/L; p = 0.001), NLR (2.69 ± 2.03 versus 1.83 ± 1.70; p = 0.006), and PLT/MPV (41.42 ± 15.86 versus 33.45 ± 17.97; p = 0.001). PLT/MPV was increased in early arrival sepsis/bacteremia infants (42.70 ± 8.57 versus 31.01 ± 8.21; p = 0.008). NLR and MPV were significantly lower in infants (≤12 months) with viral infection on late arrival (1.16 ± 1.06 versus 1.90 ± 1.25, p = 0.025 for NLR and 8.94 ± 0.95fl versus 9.44 ± 0.85fl, p = 0.046 for MPV). Conclusion: Together with standard blood biomarkers, such as CRP, neutrophils, or platelets count, PLT/MPV is a promising biomarker for clinical practice to help discriminate between viral disease or sepsis/bacteremia in all children, especially in early onset of symptoms. NLR and MPV could support exclusion of sepsis/bacteremia in late arrival cases.

A Novel Combination of Biomarkers to Herald the Onset of Sepsis Prior to the Manifestation of Symptoms

Sepsis, which kills over 200,000 patients and costs over $20 billion in the United States alone, presents a constant but preventable challenge in the healthcare system. Among the more challenging problems that it presents is misdiagnosis due to conflation with other inflammatory processes, as its mechanisms are identical to those of other inflammatory states. Unfortunately, current biomarker tests can only assess the severity and mortality risk of each case, whereas no single test exists that can predict sepsis prior to the onset of symptoms for the purpose of pre-emptive care and monitoring. We propose that a single test utilizing three, rather than two, biomarkers that appear most quickly in the blood and are the most specific for sepsis rather than trauma, may improve diagnostic accuracy and lead to lessened patient morbidity and mortality. Such a test would vastly improve patient outcomes and quality of life, prevent complications for sepsis survivors, and prevent hospital readmissions, saving the American healthcare system money. This review summarizes the current use of sepsis biomarkers to prognosticate morbidity and mortality, and rejects the current single-biomarker and even combination biomarker tests as non-specific and inaccurate for current patient needs/pro-inflammatory cytokines, general markers of inflammation, and proteins specific to myeloid cells (and therefore to infection) are discussed. Ultimately, the review suggests a three-biomarker test of procalcitonin (PCT), interleukin-6 (IL-6), and soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) to diagnose sepsis before the onset of symptoms.

Management of Acute Respiratory Failure Due to Community-Acquired Pneumonia: A Systematic Review

Community-acquired pneumonia (CAP) is a leading cause of mortality worldwide. CAP mortality is driven by the development of sepsis and acute respiratory failure (ARF). We performed a systematic review of the available English literature published in the period 1 January 1997 to 31 August 2017 and focused on ARF in CAP. The database searches identified 189 articles—of these, only 29 were retained for data extraction. Of these 29 articles, 12 addressed ARF in CAP without discussing its ventilatory management, while 17 evaluated the ventilatory management of ARF in CAP. In the studies assessing the ventilatory management, the specific treatments addressed were: high-flow nasal cannula (HFNC) (n = 1), continuous positive airway pressure (n = 2), non-invasive ventilation (n = 9), and invasive mechanical ventilation (n = 5). When analyzed, non-invasive ventilation (NIV) success rates ranged from 20% to 76% and they strongly predicted survival, while NIV failure led to an increased risk of adverse outcome. In conclusion, ARF in CAP patients may require both ventilatory and non-ventilatory management. Further research is needed to better evaluate the use of NIV and HFNC in those patients. Alongside the prompt administration of antimicrobials, the potential use of steroids and the implementation of severity scores should also be considered.

Combination of procalcitonin, C-reaction protein and carcinoembryonic antigens for discriminating between benign and malignant pleural effusions

Pleural effusion (PE) is a common manifestation associated with certain chest diseases. However, there is no effective diagnostic marker with high sensitivity and specificity. The aim of the present study was to evaluate the diagnostic performance of several biomarkers in the use of detecting malignant pleural disorder. One hundred and fifty patients with a specific diagnosis of exudative PE were enrolled in this study and were divided into the benign PE group (n=93) and the malignant PE group (n=57). Thoracoscopy was conducted to identify the reasons for the PE. Biomarkers in pleural fluid and in sera were determined either by microparticle enzyme immunoassay [carcinoembryonic antigen (CEA)], fluorescence immunoassay [procalcitonin (PCT)] or light-scattering turbidimetric immunoassay [C-reaction protein (CRP)]. Then, correlation analysis and receiver-operating characteristic (ROC) curve analysis individually or in combination were performed. The CRP and PCT levels were higher in benign PE than they were in malignant PE (PCT: P=0.017, P=0.032; CRP: P=0.001, P<0.001, respectively), while CEA levels were lower in benign PE than in malignant PE (CEA: P=0.001, P=0.001, respectively). During the ROC curve analysis, an optimal discrimination was identified by combining pleural CRP, pleural CEA and serum (s)PCT with an area under the curve of 0.973 (sensitivity, 98.9%; specificity, 89.5%). In the diagnosis of PE, there was no single biomarker that appeared to be adequately accurate. The combination of pleural CRP, pleural CEA and sPCT may represent an efficient diagnostic procedure for guiding the patient towards follow-up clinical treatment.