Applications of peptides in nanosystems for diagnosing and managing bacterial sepsis.

Sepsis represents a critical medical condition stemming from an imbalanced host immune response to infections, which is linked to a significant burden of disease. Despite substantial efforts in laboratory and clinical research, sepsis remains a prominent contributor to mortality worldwide. Nanotechnology presents innovative opportunities for the advancement of sepsis diagnosis and treatment. Due to their unique properties, including diversity, ease of synthesis, biocompatibility, high specificity, and excellent pharmacological efficacy, peptides hold great potential as part of nanotechnology approaches against sepsis. Herein, we present a comprehensive and up-to-date review of the applications of peptides in nanosystems for combating sepsis, with the potential to expedite diagnosis and enhance management outcomes. Firstly, sepsis pathophysiology, antisepsis drug targets, current modalities in management and diagnosis with their limitations, and the potential of peptides to advance the diagnosis and management of sepsis have been adequately addressed. The applications have been organized into diagnostic or managing applications, with the last one being further sub-organized into nano-delivered bioactive peptides with antimicrobial or anti-inflammatory activity, peptides as targeting moieties on the surface of nanosystems against sepsis, and peptides as nanocarriers for antisepsis agents. The studies have been grouped thematically and discussed, emphasizing the constructed nanosystem, physicochemical properties, and peptide-imparted enhancement in diagnostic and therapeutic efficacy. The strengths, limitations, and research gaps in each section have been elaborated. Finally, current challenges and potential future paths to enhance the use of peptides in nanosystems for combating sepsis have been deliberately spotlighted. This review reaffirms peptides' potential as promising biomaterials within nanotechnology strategies aimed at improving sepsis diagnosis and management.

Dual Functional Ultrasensitive Point-of-Care Clinical Diagnosis Using Metal-Organic Frameworks-Based Immunobeads.

Sepsis is an acute systemic infectious syndrome with high fatality. Fast and accurate diagnosis, monitoring, and medication of sepsis are essential. We exploited the fluorescent metal-AIEgen frameworks (MAFs) and demonstrated the dual functions of protein detection and bacteria identification: (i) ultrasensitive point-of-care (POC) detection of sepsis biomarkers (100 times enhanced sensitivity); (ii) rapid POC identification of Gram-negative/positive bacteria (selective aggregation within 20 min). Fluorescent lateral flow immunoassays (LFAs) are convenient and inexpensive for POC tests. MAFs possess a large surface area, excellent photostability, high quantum yield (∼80%), and multiple active sites serving as protein binding domains for ultrasensitive detection of sepsis biomarkers (IL-6/PCT) on LFAs. The limit of detection (LOD) for IL-6/PCT is 0.252/0.333 pg/mL. Rapid appraisal of infectious bacteria is vital to guide the use of medicines. The dual-functional fluorescent MAFs have great potential in POC tests for the clinical diagnosis of bacterial infections.

Paper-Based Biosensor for the Detection of Sepsis Using MMP-9 Biomarker in FIP Mice Model.

Sepsis is an immune response to a microbial invasion that causes organ injury and dysfunction due to a systemic inflammatory response. Sepsis is a serious, life-threatening condition and a widely recognized global health challenge. Given its high death rate, it is critical to diagnose sepsis and start treatment as early as possible. There is an urgent need for a sensitive and rapid screening method for detecting sepsis. In this study, we investigated the use of MMP-9 as a biomarker for sepsis. A colorimetric paper-based biosensor was used for the detection of MMP-9 utilizing peptide-magnetic nanoparticle conjugates. The method is based on the cleavage of the MMP-9-specific peptide by the protease leading to the detaching of the magnetic beads from the sensor surface and changing of color. A fecal intraperitoneal (FIP) challenge was used to induce sepsis in mice, and an MMP-9 secretion was measured by taking blood and Bronchoalveolar Lavage (BAL) fluid samples at 1 h, 2 h, 4 h, and 20 h (early sepsis) post-challenge intervals. The results of the paper-based sensor for the detection of MMP-9 levels in blood samples and BAL samples were compared with ELISA and Western Blot. We found that both blood and BAL levels of MMP-9 increased immediately and could be detected as early as 1 h in FIP mice post-challenge. Our work adds evidence to the assertion that MMP-9 is a reliable biomarker for the detection of sepsis at early stages.

A culture-free biphasic approach for sensitive and rapid detection of pathogens in dried whole-blood matrix.

Blood stream infections (BSIs) cause high mortality, and their rapid detection remains a significant diagnostic challenge. Timely and informed administration of antibiotics can significantly improve patient outcomes. However, blood culture, which takes up to 5 d for a negative result, followed by PCR remains the gold standard in diagnosing BSI. Here, we introduce a new approach to blood-based diagnostics where large blood volumes can be rapidly dried, resulting in inactivation of the inhibitory components in blood. Further thermal treatments then generate a physical microscale and nanoscale fluidic network inside the dried matrix to allow access to target nucleic acid. The amplification enzymes and primers initiate the reaction within the dried blood matrix through these networks, precluding any need for conventional nucleic acid purification. High heme background is confined to the solid phase, while amplicons are enriched in the clear supernatant (liquid phase), giving fluorescence change comparable to purified DNA reactions. We demonstrate single-molecule sensitivity using a loop-mediated isothermal amplification reaction in our platform and detect a broad spectrum of pathogens, including gram-positive methicillin-resistant and methicillin-susceptible Staphylococcus aureus bacteria, gram-negative Escherichia coli bacteria, and Candida albicans (fungus) from whole blood with a limit of detection (LOD) of 1.2 colony-forming units (CFU)/mL from 0.8 to 1 mL of starting blood volume. We validated our assay using 63 clinical samples (100% sensitivity and specificity) and significantly reduced sample-to-result time from over 20 h to <2.5 h. The reduction in instrumentation complexity and costs compared to blood culture and alternate molecular diagnostic platforms can have broad applications in healthcare systems in developed world and resource-limited settings.

Coagulation factor protein abundance in the pre-septic state predicts coagulopathic activities that arise during late-stage murine sepsis.

BACKGROUND: Although sepsis accounts for 1 in 5 deaths globally, few molecular therapies exist for this condition. The development of effective biomarkers and treatments for sepsis requires a more complete understanding of host responses and pathogenic mechanisms at early stages of disease to minimize host-driven pathology. METHODS: An alternative to the current symptom-based approach used to diagnose sepsis is a precise assessment of blood proteomic changes during the onset and progression of Salmonella Typhimurium (ST) murine sepsis. FINDINGS: A distinct pattern of coagulation factor protein abundance was identified in the pre-septic state- prior to overt disease symptoms or bacteremia- that was predictive of the dysregulation of fibrinolytic and anti-coagulant activities and resultant consumptive coagulopathy during ST murine sepsis. Moreover, the changes in protein abundance observed generally have the same directionality (increased or decreased abundance) reported for human sepsis. Significant overlap of ST coagulopathic activities was observed in Gram-negative Escherichia coli- but not in Gram-positive staphylococcal or pneumococcal murine sepsis models. Treatment with matrix metalloprotease inhibitors prevented aberrant inflammatory and coagulopathic activities post-ST infection and increased survival. Antibiotic treatment regimens initiated after specific changes arise in the plasma proteome post-ST infection were predictive of an increase in disease relapse and death after cessation of antibiotic treatment. INTERPRETATION: Altered blood proteomics provides a platform to develop rapid and easy-to-perform tests to predict sepsis for early intervention via biomarker incorporation into existing blood tests prompted by patient presentation with general malaise, and to stratify Gram-negative and Gram-positive infections for appropriate treatment. Antibiotics are less effective in microbial clearance when initiated after the onset of altered blood proteomics as evidenced by increased disease relapse and death after termination of antibiotic therapy. Treatment failure is potentially due to altered bacterial / host-responses and associated increased host-driven pathology, providing insight into why delays in antibiotic administration in human sepsis are associated with increased risk for death. Delayed treatment may thus require prolonged therapy for microbial clearance despite the prevailing notion of antibiotic de-escalation and shortened courses of antibiotics to improve drug stewardship. FUNDING: National Institutes of Health, U.S. Army.

Accuracy and Impact on Patient Management of New Tools for Diagnosis of Sepsis: Experience with the T2 Magnetic Resonance Bacteria Panel.

The rapid and accurate identification of pathogens responsible for sepsis is essential for prompt and effective antimicrobial therapy. Molecular technologies have been developed to detect the most common causative agents, with high sensitivity and short time to result (TTR). T2 Bacteria Panel (T2), based on a combination of PCR and T2 magnetic resonance, can identify directly in blood samples Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, Enterococcus faecium, and Acinetobacter baumannii pathogens. This study evaluates the role of T2 in the diagnosis of sepsis and its impact on patient management, specifically in terms of TTR and the switch from empirical to directed therapy, comparing results of blood culture (BC) and T2 assay in 82 patients with sepsis. T2 significantly improved the detection of the causative agents of sepsis. For pathogens included in the panel, T2 sensitivity was 100% (95% CI 86.3-100.0), significantly higher than that of BC (54.8%, 95% CI 36.0-72.7). The TTR (median, IQR) of positive T2 (3.66 h, 3.59-4.31) was significantly shorter than that of the positive BC (37.58 h, 20.10-47.32). A significant reduction in the duration of empiric therapy and an increase in the percentage of patients with switched therapy was observed in patients with a positive T2 result. In conclusion, T2 can shorten and improve the etiological diagnosis of sepsis with a positive impact on patient management.

Sepsis scoring systems and use of the Sepsis six care bundle in maternity hospitals.

BACKGROUND: This study aimed to assess the predictive power of three different Sepsis Scoring Systems (SSSs), namely maternity Systematic Inflammatory Response Syndrome (mSIRS), quick Sepsis-related Organ Failure Assessment (qSOFA) and Modified Early Warning System (MEWS) in identifying sepsis by comparing them with positive culture. This study also sought to evaluate compliance with using the Sepsis Six Care Bundle (SSCB) operated in an individual health board. METHODS: A retrospective cohort study was conducted in 3 maternity hospitals of a single Scottish health board that admitted 2690 pregnancies in a 12 weeks period in 2016. Data for study was obtained from medical notes, handheld and electronic health records for women who were prescribed antibiotics with a confirmed or suspected diagnosis of sepsis. Data on clinical parameters was used to classify women according to mSIRS, qSOFA and MEWS as having sepsis or not and this was compared to results of positive culture to obtain sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and area under Receiver Operating Characteristic curve (AUROC) along with their 95% confidence intervals. Data was also obtained on SSCB compliance. RESULTS: A total of 89 women were diagnosed with sepsis, of which 14 had missing data, leaving 75 for final analysis. Sensitivity, specificity, PPV, NPV and AUROC of mSIRS and MEWS were almost similar with AUROC of both being around 50%. Only 33 (37.1%) had identifiable sepsis six sticker displayed on medical notes and only 2 (2.2%) had all elements of SSCB delivered within the recommended one-hour post-diagnosis period. Blood culture and full blood count with other lab tests had been performed for most women (97%) followed by intravenous antibiotics and fluids (93.9%). CONCLUSIONS: mSIRS and MEWS were quite similar in detecting sepsis when compared to positive culture, with their ability to detect sepsis being close to chance. This underlines the need for creating a valid SSS with high sensitivity and specificity for clinical use in obstetric settings. Clinical use of SSCB was limited despite it being a health board policy, although there is considerable possibility of improvement following detailed audits and removal of barriers for implementing SSCB.

Assessment of a Cellular Host Response Test as a Sepsis Diagnostic for Those With Suspected Infection in the Emergency Department.

OBJECTIVES: Sepsis is a common cause of morbidity and mortality. A reliable, rapid, and early indicator can help improve efficiency of care and outcomes. To assess the IntelliSep test, a novel in vitro diagnostic that quantifies the state of immune activation by measuring the biophysical properties of leukocytes, as a rapid diagnostic for sepsis and a measure of severity of illness, as defined by Sequential Organ Failure Assessment and Acute Physiology and Chronic Health Evaluation-II scores and the need for hospitalization. DESIGN SETTING SUBJECTS: Adult patients presenting to two emergency departments in Baton Rouge, LA, with signs of infection (two of four systemic inflammatory response syndrome criteria, with at least one being aberration of temperature or WBC count) or suspicion of infection (a clinician order for culture of a body fluid), were prospectively enrolled. Sepsis status, per Sepsis-3 criteria, was determined through a 3-tiered retrospective and blinded adjudication process consisting of objective review, site-level clinician review, and final determination by independent physician adjudicators. MEASUREMENTS AND MAIN RESULTS: Of 266 patients in the final analysis, those with sepsis had higher IntelliSep Index (median = 6.9; interquartile range, 6.1-7.6) than those adjudicated as not septic (median = 4.7; interquartile range, 3.7-5.9; p < 0.001), with an area under the receiver operating characteristic curve of 0.89 and 0.83 when compared with unanimous and forced adjudication standards, respectively. Patients with higher IntelliSep Index had higher Sequential Organ Failure Assessment (3 [interquartile range, 1-5] vs 1 [interquartile range, 0-2]; p < 0.001) and Acute Physiology and Chronic Health Evaluation-II (7 [interquartile range, 3.5-11.5] vs 5 [interquartile range, 2-9]; p < 0.05) and were more likely to be admitted to the hospital (83.6% vs 48.3%; p < 0.001) compared with those with lower IntelliSep Index. CONCLUSIONS: In patients presenting to the emergency department with signs or suspicion of infection, the IntelliSep Index is a promising tool for the rapid diagnosis and risk stratification for sepsis.

Leukocyte Activation Profile Assessed by Raman Spectroscopy Helps Diagnosing Infection and Sepsis.

OBJECTIVES: Leukocytes are first responders to infection. Their activation state can reveal information about specific host immune response and identify dysregulation in sepsis. This study aims to use the Raman spectroscopic fingerprints of blood-derived leukocytes to differentiate inflammation, infection, and sepsis in hospitalized patients. Diagnostic sensitivity and specificity shall demonstrate the added value of the direct characterization of leukocyte's phenotype. DESIGN: Prospective nonrandomized, single-center, observational phase-II study (DRKS00006265). SETTING: Jena University Hospital, Germany. PATIENTS: Sixty-one hospitalized patients (19 with sterile inflammation, 23 with infection without organ dysfunction, 18 with sepsis according to Sepsis-3 definition). INTERVENTIONS: None (blood withdrawal). MEASUREMENTS AND MAIN RESULTS: Individual peripheral blood leukocytes were characterized by Raman spectroscopy. Reference diagnostics included established clinical scores, blood count, and biomarkers (C-reactive protein, procalcitonin and interleukin-6). Binary classification models using Raman data were able to distinguish patients with infection from patients without infection, as well as sepsis patients from patients without sepsis, with accuracies achieved with established biomarkers. Compared with biomarker information alone, an increase of 10% (to 93%) accuracy for the detection of infection and an increase of 18% (to 92%) for detection of sepsis were reached by adding the Raman information. Leukocytes from sepsis patients showed different Raman spectral features in comparison to the patients with infection that point to the special immune phenotype of sepsis patients. CONCLUSIONS: Raman spectroscopy can extract information on leukocyte's activation state in a nondestructive, label-free manner to differentiate sterile inflammation, infection, and sepsis.

Microfluidic Chips for Sepsis Diagnosis.

This chapter discusses two microfluidic-based approaches for early sepsis detection that achieve a higher accuracy than traditional blood culture analysis. Patient blood samples were included in this work to validate the performance of our chips in diagnosing sepsis. The single-parameter chip demonstrated the increased accuracy if using CD64 as a biomarker for sepsis detection compared with C-reactive protein (CRP) and procalcitonin (PCT) when applied alone. In addition, a multiparameter chip measuring a combined panel of CD25, CD64, and CD69, and achieved a high accuracy with an Area Under the Receiver Operating Characteristic Curve (AUROC) of 0.978. The combined panel was also able to detect culture-negative patients and provided a faster diagnosis. Besides, microfluidics has advantages of less time consuming, easier to manufacture, less sample loading, less complex, and portable. Therefore, our approach is of great potential to become a bedside sepsis detection method.

2,4-Dinitrophenol: 'diet' drug death following major trauma.

There has been a resurgence in the illicit use of 2,4-dinitrophenol by people wishing to achieve rapid weight loss. Despite its availability, the drug is banned for human consumption as it is toxic and can have fatal consequences. We present the case of a 23-year-old man who regularly consumed 2,4-dinitrophenol to generate fat loss without apparent ill effect. He was involved in a high-speed road traffic collision and sustained limb-threatening injuries. The combination of emergency surgery, trauma and 2,4-dinitrophenol consumption culminated in deterioration under anaesthesia, with subsequent death from multiorgan failure in the intensive care unit 48 h later. Previous cases have reported death from 2,4-dinitrophenol toxicity alone. We believe this is the first reported case of 2,4-dinitrophenol toxicity triggered by the additional physiological stress of polytrauma and emergency surgery.

The potential of FT-IR spectroscopy for improving healthcare in sepsis - An animal model study.

Fourier Transform-Infrared (FT-IR) absorption spectroscopy has been used to investigate pathophysiological changes caused by sepsis. Sepsis has been defined as a potentially fatal organic dysfunction caused by a dysregulated host response to infection and can lead a patient to risk of death. This study used samples consisting of the blood plasma of mice which were induced to sepsis state, compared to a healthy group using FT-IR associated with attenuated total reflectance (ATR) spectroscopy. For statistical analysis, principal components analysis (PCA) and linear discriminant analysis (LDA) were applied, independently, to the second derivative spectra of both the fingerprint (900-1800 cm-1) and the high wavenumber (2800-3100 cm-1) regions. The technique efficiently differentiated the blood plasma of the two groups, sepsis and healthy mice, the analysis indicating that fatty acids and lipids in the blood samples could be an important biomarker of sepsis.

Post-Mortem Investigations for the Diagnosis of Sepsis: A Review of Literature.

To date, sepsis is still one of the most important causes of death due to the difficulties concerning the achievement of a correct diagnosis. As well as in a clinical context, also in a medico-legal setting the diagnosis of sepsis can reveal challenging due to the unspecificity of the signs detected during autopsies, especially when no ante-mortem clinical data, laboratory, and cultural results are available. Thus, a systematic review of literature was performed to provide an overview of the main available and updated forensic tools for the post-mortem diagnosis of sepsis. Moreover, the aim of this review was to evaluate whether a marker or a combination of markers exist, specific enough to allow a correct and definite post-mortem diagnosis. The review was conducted searching in PubMed and Scopus databases, and using variable combinations of the keywords "post mortem sepsis diagnosis", "macroscopic signs", "morphology", "histology", "immunohistochemical markers", "biochemical markers", and "forensic microbiology". The article selection was carried out following specific inclusion and exclusion criteria. A total of 44 works was identified, providing data on morphological aspects of the organs examined, histological findings, immunohistochemical and biochemical markers, and cultural assays. The review findings suggested that the post-mortem diagnosis of sepsis can be achieved by a combination of data obtained from macroscopic and microscopic analysis and microbial investigations, associated with the increased levels of at least two of three biochemical and/or immunohistochemical markers evaluated simultaneously on blood samples.

Indwelling medical device use and sepsis risk at a health professional shortage area hospital: Possible interaction with length of hospitalization.

BACKGROUND: We aimed to identify risk factors for sepsis diagnosis and possible interaction with length of hospital stay (LOS) among inpatients at a rural Health Professional Shortage Area hospital. METHODS: This case-control study examined 600 adult patients (300 cases and 300 controls) admitted to a rural health system in North Carolina between 2012 and 2018. Case selection was based on assignment of ICD-9-CM diagnostic codes for sepsis. Controls were patients with a medical diagnosis other than sepsis during the observational period. Logistic regression was used to model sepsis diagnosis as a function of indwelling medical device use and stratified by LOS. RESULTS: Indwelling medical device use preadmission and postadmission were significantly associated with increased risk of sepsis diagnosis among patients with extended hospital stays (LOS ≥ 5 days) (odds ratio [OR] = 5.51; 95% confidence interval [CI] = 1.95-15.62; P = .001 and OR = 3.28; 95% CI = 1.24-8.68; P = .017, respectively). Among patients with LOS <5 days, association with sepsis diagnosis was only significant for indwelling medical device use preadmission (OR = 9.61; 95% CI = 3.68-25.08; P < .0001). CONCLUSIONS: Indwelling medical device use was significantly associated with increased risk of sepsis diagnosis and the risk was higher with longer hospitalization.

Neonatal sepsis in low-income countries: epidemiology, diagnosis and prevention.

Introduction: Sepsis accounts for up to one-third of neonatal deaths in the world each year. The World Health Organization acknowledges neonatal sepsis as a major global health concern, and that the highest burden occurs in low- and middle-income countries (LMICs). Despite major research and clinical progress in this area, we still lack accurate diagnostic tools for neonatal sepsis, complicating the management of this condition.Areas covered: The purpose here is to review the latest data on the incidence, diagnosis, prevention, and management of neonatal sepsis in LMIC. We discuss the limitations of current diagnostic tests - including their lack of availability - and how this may influence global estimates of cases. We review the benefits of antenatal, intrapartum, and post-natal preventive measures. We briefly discuss the management, highlighting the emergence of antimicrobial resistance. Finally, we expose some high priority areas.Expert opinion: Neonatal sepsis is a challenging condition requiring a multifaceted approach to address the major diagnostic issues, but also the underlying socio-economic causes that nourish epidemic cases in LMIC. Focusing on antibiotics as a main pillar of intervention is likely to engender antimicrobial resistance, eventually hindering the appreciable gains LMICs have achieved in neonatal health outcomes.

Prehospital Antibiotics Improve Morbidity and Mortality of Emergency Medical Service Patients with Sepsis.

Background: Severe sepsis is a major cause of mortality in patients evaluated in the Emergency Department (ED). Early initiation of antibiotic therapy and IV fluids in the ED is associated with improved outcomes. We investigated whether early administration of antibiotics in the prehospital setting improves outcomes in these patients with sepsis. Methods: This is a retrospective study comparing outcomes of patients meeting sepsis criteria in the field by EMS, who were treated with IV fluids and antibiotics. Their outcomes were compared with controls where fluids were administered prehospital and antibiotics were initiated in the ED. We compared morbidity and mortality between these groups. Results: Early antibiotics and fluids were demonstrated to show significant improvement in outcomes in the patients meeting sepsis criteria treated in the pre-hospital setting. The average age for sepsis patients receiving antibiotics in the prehospital setting was statistically higher than that for patients in the historical control group, 73.23 years and 67.67, respectively (p < 0.036), and there was no statistically significant difference of Charlson Comorbidity Index between the groups (p two-tail = 0.28). Average intensive care unit length of stay was 2.51 days in the in the prehospital group and 5.18 days in the historical controls, and the prehospital group received fewer blood products than the historical controls (p = 0.0003). Conclusions: Early IV administration of antibiotics in the field significantly improves outcome in EMS patients who meet sepsis criteria based on a modified qSOFA score.

Vascular Endothelium in Neonatal Sepsis: Basic Mechanisms and Translational Opportunities.

Neonatal sepsis remains a major health issue worldwide, especially for low-birth weight and premature infants, with a high risk of death and devastating sequelae. Apart from antibiotics and supportive care, there is an unmet need for adjunctive treatments to improve the outcomes of neonatal sepsis. Strong and long-standing research on adult patients has shown that vascular endothelium is a key player in the pathophysiology of sepsis and sepsis-associated organ failure, through a direct interaction with pathogens, leukocytes, platelets, and the effect of soluble circulating mediators, in part produced by endothelial cells themselves. Despite abundant evidence that the neonatal immune response to sepsis is distinct from that of adults, comparable knowledge on neonatal vascular endothelium is much more limited. Neonatal endothelial cells express lower amounts of adhesion molecules compared to adult ones, and present a reduced capacity to neutralize reactive oxygen species. Conversely, available evidence on biomarkers of endothelial damage in neonates is not as robust as in adult patients, and endothelium-targeted therapeutic opportunities for neonatal sepsis are almost unexplored. Here, we summarize current knowledge on the structure of neonatal vascular endothelium, its interactions with neonatal immune system and possible endothelium-targeted diagnostic and therapeutic tools for neonatal sepsis. Furthermore, we outline areas of basic and translational research worthy of further study, to shed light on the role of vascular endothelium in the context of neonatal sepsis.

Detection of culture-negative sepsis in clinical blood samples using a microfluidic assay for combined CD64 and CD69 cell capture.

Sepsis is a life-threatening disease that affects millions of people every year. Rapid detection of sepsis assists clinicians to initiate timely antibiotic therapy and to reduce mortality. At the same time, accurate point-of-care detection is needed to reduce unnecessary use of antibiotics. One of the principal challenges in sepsis diagnosis is that many sepsis cases do not result in positive blood cultures. These so-called culture-negative cases present a significant health threat. In this work, we present a microfluidic cells separation system for the detection of sepsis in both culture-positive and culture-negative cases. Leukocytes were captured in several affinity separation zones of a microchip based on CD64, CD69, and CD25 expression. To validate this assay 40 septic patients and 10 healthy volunteers were enrolled in this study. Septic patients were divided into culture-positive (n = 12) and culture-negative cases (n = 21). CD64 + cell capture demonstrated excellent accuracy for sepsis detection with an area under the receiver operating characteristic curves (AUC) of 0.962. A combined panel of CD64 + and CD69 + cell counts was constructed, and the new panel outperformed each of these two biomarkers alone with the AUC of 0.978. Our affinity microfluidic devices were validated by conventional flow cytometry analysis. Results showed that the cell capture number of specific affinity region increased along with the increase of its corresponding antigen expression. This clinical validation confirms that CD64 and CD69 cell separations are a powerful sepsis assay with the potential for point-of-care analysis in culture-positive and culture-negative cases.

Razão neutrófilo-linfócito no diagnóstico precoce de sepse em unidade de terapia intensiva: um estudo de caso-controle / Neutrophil-lymphocyte ratio in the early diagnosis of sepsis in an intensive care unit: a case-control study

RESUMO Objetivo: Avaliar a razão neutrófilo-linfócito na predição de sepse e mortalidade em pacientes admitidos em uma unidade de terapia intensiva. Métodos: Estudo de caso-controle de pacientes adultos admitidos em terapia intensiva. Foram incluídos como casos pacientes que tiveram sepse como razão de admissão e possuíam exame laboratorial de hemograma prévio. As análises estatísticas realizadas foram curva ROC, regressão logística binária, Mann Whitney e qui-quadrado de Pearson. Foi considerado significativo valor de p < 0,05. Resultados: Os valores de curva ROC foram 0,62 para razão neutrófilo-linfócito, 0,98 para neutrófilos bastonados e 0,51 para leucócitos totais. A presença de razão neutrófilo-linfócito superior a 5,0, o número de leucócitos acima de 12.000mm3/mL e número de neutrófilos bastonados acima 10% foram fatores de risco para sepse, entretanto somente os escores SAPS 3 e SOFA estavam relacionados a mortalidade dos pacientes. Conclusão: A razão neutrófilo-linfócito e os neutrófilos bastonados em combinação com outros parâmetros podem ser marcadores na detecção precoce de sepse em terapia intensiva.

ABSTRACT Objective: To evaluate the neutrophil-lymphocyte ratio as a predictor of sepsis and mortality in patients admitted to an intensive care unit. Methods: Case-control study of adult patients admitted to an intensive care unit. Patients who had sepsis as the reason for admission and who had a previous complete blood count examination were included as case patients. The following statistical analyses were performed: ROC curves, binary logistic regression, and Mann-Whitney and Pearson's chi-square tests. p < 0.05 was considered significant. Results: The ROC curve values were 0.62 for neutrophil-lymphocyte ratio, 0.98 for band neutrophils and 0.51 for total leukocytes. The presence of a neutrophil-lymphocyte ratio greater than 5.0, leukocyte count above 12,000mm3/mL and band neutrophil percentage above 10% were risk factors for sepsis; however, only the SAPS 3 and SOFA score were related to patient mortality. Conclusion: The neutrophil-lymphocyte ratio and band neutrophils in combination with other parameters may be markers for the early detection of sepsis in intensive care units.

The value of delta neutrophil index in neonatal sepsis diagnosis, follow-up and mortality prediction.

BACKGROUND: The complete blood cell count (CBC) and peripheral blood smear were the most commonly ordered tests for the diagnosis of neonatal sepsis. Delta neutrophil index (DNI) shows leucocyte differentiation and calculated while CBC is performed. AIMS: We aimed to evaluate the value of DNI in neonatal sepsis. STUDY DESIGN: DNI was measured with Siemens Advia 2120 and 2120i devices. DNI was calculated as (neutrophil and eosinophil count in myeloperoxidase channel)-(polymorphonuclear leucocyte count in nuclear lobularity channel). RESULTS: Study population included 141 and 87 neonates in sepsis (110 proven, 31 clinical) and control groups. Demographic characters were similar between groups. Proven sepsis group had lower birthweight and higher late-onset sepsis rate than clinical sepsis and control groups. Median DNI (16.3 vs 1,4) and CRP (6.8 vs 0,03 mg/dl) were significantly higher in sepsis group. Proven sepsis group had significantly higher DNI level than clinical sepsis group (20.8 vs 9.1). Cut-off level of DNI was 4.6 with 85% sensitivity and 80% specificity. Cut-off level of CRP was 0.58 mg/dl with 81% sensitivity and 82% specificity. Combination of DNI and CRP gave 98% sensitivity and 76% specificity. Mortality rate in sepsis group was 39%. Median DNI level in patients with mortality was significantly higher (30.1 vs 9.6). Cut-off level of DNI for mortality prediction was 16.1 with 75% sensitivity and 65% specificity. Follow-up levels of DNI was significantly decreased in 6-10 days to normal levels (16.3 to 4.2). CONCLUSIONS: DNI was found to be useful in the diagnose, follow-up and mortality prediction of neonatal sepsis without extra blood to CBC.