Absolute eosinophils count as a marker of mortality in patients with severe sepsis and septic shock in an intensive care unit

Integrated Analysis Identified TGFBI as a Biomarker of Disease Severity and Prognosis Correlated with Immune Infiltrates in Patients with Sepsis

Background

Sepsis is a major contributor to morbidity and mortality among hospitalized patients. This study aims to identify markers associated with the severity and prognosis of sepsis, providing new approaches for its management and treatment.

Methods

Data were mined from the Gene Expression Omnibus (GEO) databases and were analyzed by multiple statistical methods like the Spearman correlation coefficient, Kaplan-Meier analysis, Cox regression analysis, and functional enrichment analysis. Candidate indicator' associations with immune infiltration and roles in sepsis development were evaluated. Additionally, we employed techniques such as flow cytometry and neutral red staining to evaluate its impact on macrophage functions like polarization and phagocytosis.

Results

Twenty-eight genes were identified as being closely linked to the severity of sepsis, among which transforming growth factor beta induced (TGFBI) emerged as a distinct marker for predicting clinical outcomes. Notably, reductions in TGFBI expression during sepsis correlate with poor prognosis and rapid disease progression. Elevated expression of TGFBI has been observed to mitigate abnormalities in sepsis-related immune cell infiltration that are critical to the pathogenesis and prognosis of the disease, including but not limited to type 17 T helper cells and activated CD8 T cells. Moreover, the protein-protein interaction network revealed the top ten genes that interact with TGFBI, showing significant involvement in the regulation of the actin cytoskeleton, extracellular matrix-receptor interactions, and phagosomes. These are pivotal elements in the formation of phagocytic cups by macrophages, squaring the findings of the Human Protein Atlas. Additionally, we discovered that TGFBI expression was significantly higher in M2-like macrophages, and its upregulation was found to inhibit lipopolysaccharide-induced polarization and phagocytosis in M1-like macrophages, thereby playing a role in preventing the onset of inflammation.

Conclusion

TGFBI warrants additional exploration as a promising biomarker for assessing illness severity and prognosis in patients with sepsis, considering its significant association with immunological and inflammatory responses in this condition.

Association between Eosinophil Count and Cortisol Concentrations in Equids Admitted in the Emergency Unit with Abdominal Pain

Stress leukogram includes eosinopenia as one of its main markers (neutrophilia, eosinopenia, lymphopenia, and mild monocytosis). Cortisol is the main stress biomarker, which is also strongly correlated with the severity of gastrointestinal diseases. This study aimed to determine the relationship between salivary cortisol and the eosinophil cell count (EC) in equids with abdominal pain. To do this, 39 horses with abdominal pain referred to an emergency service were included. All samples were taken on admission, and several parameters and clinical data were included. Equids were classified according to the outcome as survivors and non-survivors. Non-surviving equids presented higher salivary cortisol concentrations (Non-Survivors: 1.580 ± 0.816 µg/dL; Survivors 0.988 ± 0.653 µg/dL; p < 0.05) and lower EC (Non-Survivors: 0.0000 × 103/µL (0.000/0.0075); Survivors: 0.0450 × 103/µL (0.010/0.1825); p < 0.01). In addition, the relationship between salivary cortisol concentration, EC, and the WBC was determined. Only a strong correlation (negative) was observed between cortisol and EC (r = -0.523, p < 0.01). Since cortisol is not an analyte that can be measured routinely in clinical settings such as emergencies, the EC could be a good alternative. While the results are promising, further studies are needed before EC can be used confidently in routine practice to predict survival in cases of abdominal pain.

Comprehensive analysis of immune cell landscapes revealed that immune cell ratio eosinophil/B.cell.memory is predictive of survival in sepsis

BACKGROUND

Immune dysregulation is a feature of sepsis. However, a comprehensive analysis of the immune landscapes in septic patients has not been conducted.

OBJECTIVES

This study aims to explore the abundance ratios of immune cells in sepsis and investigate their clinical value.

METHODS

Sepsis transcriptome data sets were downloaded from the NCBI GEO database. The immunedeconv R package was employed to analyze the abundance of immune cells in sepsis patients and calculate the ratios of different immune cell types. Differential analysis of immune cell ratios was performed using the t test. The Spearman rank correlation coefficient was utilized to find the relationships between immune cell abundance and pathways. The prognostic significance of immune cell ratios for patient survival probability was assessed using the log-rank test. In addition, differential gene expression was performed using the limma package, and gene co-expression analysis was executed using the WGCNA package.

RESULTS

We found significant changes in immune cell ratios between sepsis patients and healthy controls. Some of these ratios were associated with 28-day survival. Certain pathways showed significant correlations with immune cell ratios. Notably, six immune cell ratios demonstrated discriminative ability for patients with systemic inflammatory response syndrome (SIRS), bacterial sepsis, and viral sepsis, with an Area Under the Curve (AUC) larger than 0.84. Patients with a high eosinophil/B.cell.memory ratio exhibited poor survival outcomes. A total of 774 differential genes were identified in sepsis patients with a high eosinophil/B.cell.memory ratio compared to those with a low ratio. These genes were organized into seven co-expression modules associated with relevant pathways, including interferon signaling, T-cell receptor signaling, and specific granule pathways.

CONCLUSIONS

Immune cell ratios eosinophil/B.cell.memory and NK.cell.activated/NK.cell.resting in sepsis patients can be utilized for disease subtyping, prognosis, and diagnosis. The proposed cell ratios may have higher prognostic values than the neutrophil-to-lymphocyte ratio (NLR).

Predictive Value of the Baseline and Early Changes in Blood Eosinophils for Short-Term Mortality in Patients with Acute Respiratory Distress Syndrome

Background

Eosinophils play an essential role in the pathogenesis of acute respiratory distress syndrome (ARDS). We aimed to assess the association between the baseline blood eosinophils, eosinophil changes during the first week in the intensive care unit (ICU) and short-term patient outcomes.

Methods

All patients meeting the Berlin definition of ARDS from the Medical Information Mart for Intensive Care IV database were retrospectively analyzed. We used logistic regression, Kaplan–Meier survival and random forest analysis to determine the association between the baseline eosinophils and short-term mortality. Then the trends in eosinophils over time were compared between the survivors and non-survivors using a generalized additive mixed model (GAMM), which is a common approach used for analysis of repeated measurement data. Area under the receiver-operating characteristic curve (AUC) was used to evaluate the predictive value.

Results

A total of 1685 patients were included, and the 30-day mortality was 25.1%. Kaplan–Meier analysis showed that patients with high baseline eosinophils (>0.3%) had lower 30-day mortality (p < 0.001). Random forest model selected the baseline eosinophils as an important factor associated with 30-day mortality. Multivariable logistic regression analysis identified high baseline eosinophils as an independent factor for 30-day mortality (OR 0.743, 95% CI 0.568–0.970). The GAMM result showed that the levels of eosinophils were increased in both survival and non-survival groups, and the between-group differences increased over time, with an average of 0.154 daily after adjusting for confounders. The AUC of changes in eosinophils within the first week was significantly higher than that of baseline eosinophils.

Conclusion

There is a negative association between the baseline eosinophils and short-term mortality in ARDS patients, and the differences in eosinophils increased over time between the survivors and non-survivors. Higher increase in eosinophils is associated with decreased short-term mortality, and dynamic monitoring of eosinophils could better predict the survival of ARDS patients.

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Silent existence of eosinopenia in sepsis: a systematic review and meta-analysis

BACKGROUND

Sepsis is a life-threatening and time-critical medical emergency; therefore, the early diagnosis of sepsis is essential to timely treatment and favorable outcomes for patients susceptible to sepsis. Eosinopenia has been identified as a potential biomarker of sepsis in the past decade. However, its clinical application progress is slow and its recognition is low. Recent studies have again focused on the potential association between Eosinopenia and severe infections. This study analyzed the efficacy of Eosinopenia as a biomarker for diagnosis of sepsis and its correlation with pathophysiology of sepsis.

METHOD

The protocol for this meta-analysis is available in PROSPERO (CRD42020197664). We searched PubMed, EMBASE, Web of Science, and Cochrane Central Register of Controlled Trials CENTRAL databases to identify studies that met the inclusion criteria. Two authors performed data extraction independently. The pooled outcomes were calculated by TP (true positive), FP (false positive), FN (false negative), TN (true negative) by using bivariate meta-analysis model in STATA 14.0 software. Meanwhile, possible mechanisms of sepsis induced Eosinopenia was also analyzed.

RESULTS

Seven studies were included in the present study with a total number of 3842 subjects. The incidence of Eosinopenia based on the enrolled studies varied from 23.2 to 92.7%. For diagnosis of sepsis, the pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and diagnostic odds ratio of Eosinopenia were 0.66 (95%CI [0.53-0.77]), 0.68 (95%CI [0.56-0.79]), 2.09 (95%CI [1.44-3.02]), 0.49 (95%CI [0.34-0.71]) and 4.23 (95%CI [2.15-8.31]), respectively. The area under the summary receiver operator characteristic curve (SROC) was 0.73 (95%CI [0.68-0.76]). Meta-regression analysis revealed that no single parameter accounted for the heterogeneity of pooled outcomes. For each subgroup of different eosinopenia cutoff values (50, 40, ≤25, 100), the sensitivity was 0.61, 0.79, 0.57, 0.54, and the specificity was 0.61, 0.75, 0.83, 0.51, respectively.

CONCLUSIONS

Our findings suggested that Eosinopenia has a high incidence in sepsis but has no superiority in comparison with conventional biomarkers for diagnosis of sepsis. However, eosinopenia can still be used in clinical diagnosis for sepsis as a simple, convenient, fast and inexpensive biomarker. Therefore, further large clinical trials are still needed to re-evaluate eosinopenia as a biomarker of sepsis.

The role of eosinophils in sepsis and acute respiratory distress syndrome: a scoping review

PURPOSE

Septic shock and acute respiratory distress syndrome (ARDS) are characterized by a dysregulated immune host response that may respond to steroid therapy. Eosinophils contribute to type 2 inflammation that often responds to steroid therapy; their role in immune dysregulation and outcomes in sepsis and ARDS is unclear.

SOURCE

A systematic search of Cochrane Library, MEDLINE, and EMBASE was performed from inception to 9 September 2020. The search comprised the following terms: eosinophils, sepsis, septic shock, and ARDS. Two reviewers independently screened abstracts and texts and extracted data on disease severity and clinical outcomes.

PRINCIPAL FINDINGS

Thirty-nine studies were identified: 30 evaluated serum eosinophil count in sepsis, one evaluated eosinophil activity in sepsis, three assessed bronchoalveolar lavage (BAL) eosinophil count in ARDS, four assessed eosinophil activity in ARDS, and one assessed peripheral eosinophil count in ARDS. Eleven studies showed an association between eosinopenia and sepsis, and eight studies found persistent eosinopenia at > 48 hr of intensive care unit admission to predict mortality and readmission in septic patients. Three studies found BAL eosinophil count to be low in ARDS, although one found that levels rose in late-phase ARDS. Three studies found eosinophil activity markers in BAL to be high in ARDS and correlate with ARDS severity.

CONCLUSION

Persistent peripheral eosinopenia is a marker of bacterial sepsis and is independently associated with poor outcomes. Bronchoalveolar lavage eosinophil counts are low in early-phase ARDS, but increase in late-phase ARDS, while elevated markers of eosinophil activity correlate with ARDS severity. Further studies understanding the mechanisms leading to eosinopenia in sepsis and increased eosinophil activity in ARDS are needed.

Do Blood Eosinophils Predict in-Hospital Mortality or Severity of Disease in SARS-CoV-2 Infection? A Retrospective Multicenter Study

Introduction: Healthcare systems worldwide have been battling the ongoing COVID-19 pandemic. Eosinophils are multifunctional leukocytes implicated in the pathogenesis of several inflammatory processes including viral infections. We focus our study on the prognostic value of eosinopenia as a marker of disease severity and mortality in COVID-19 patients. Methods: Between 1 March and 30 April 2020, we conducted a multicenter and retrospective study on a cohort of COVID-19 patients (moderate or severe disease) who were hospitalized after presenting to the emergency department (ED). We led our study in six major hospitals of northeast France, one of the outbreak’s epicenters in Europe. Results: We have collected data from 1035 patients, with a confirmed diagnosis of COVID-19. More than three quarters of them (76.2%) presented a moderate form of the disease, while the remaining quarter (23.8%) presented a severe form requiring admission to the intensive care unit (ICU). Mean circulating eosinophils rate, at admission, varied according to disease severity (p < 0.001), yet it did not differ between survivors and non-survivors (p = 0.306). Extreme eosinopenia (=0/mm³) was predictive of severity (aOR = 1.77, p = 0.009); however, it was not predictive of mortality (aOR = 0.892, p = 0.696). The areas under the Receiver operating characteristics (ROC) curve were, respectively, 58.5% (CI95%: 55.3–61.7%) and 51.4% (CI95%: 46.8–56.1%) for the ability of circulating eosinophil rates to predict disease severity and mortality. Conclusion: Eosinopenia is very common and often profound in cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Eosinopenia was not a useful predictor of mortality; however, undetectable eosinophils (=0/mm³) were predictive of disease severity during the initial ED management.

Harnessing the Versatility of Invariant NKT Cells in a Stepwise Approach to Sepsis Immunotherapy

Sepsis results from a heavy-handed response to infection that may culminate in organ failure and death. Many patients who survive acute sepsis become immunosuppressed and succumb to opportunistic infections. Therefore, to be successful, sepsis immunotherapies must target both the initial and the protracted phase of the syndrome to relieve early immunopathology and late immunosuppression, respectively. Invariant NKT (iNKT) cells are attractive therapeutic targets in sepsis. However, repeated treatments with α-galactosylceramide, the prototypic glycolipid ligand of iNKT cells, result in anergy. We designed a double-hit treatment that allows iNKT cells to escape anergy and exert beneficial effects in biphasic sepsis. We tested the efficacy of this approach in the sublethal cecal ligation and puncture mouse model, which mirrors polymicrobial sepsis with progression to an immunosuppressed state. Septic mice were treated with [(C2S, 3S, 4R)-1-O-(α-d-galactopyranosyl)-N-tetracosanoyl-2-amino-1,3,4-nonanetriol] (OCH), a T_H2-polarizing iNKT cell agonist, before they received α-galactosylceramide. This regimen reduced the morbidity and mortality of cecal ligation and puncture, induced a transient but robust IFN-γ burst within a proinflammatory cytokine/chemokine landscape, transactivated NK cells, increased MHC class II expression on macrophages, and restored delayed-type hypersensitivity to a model hapten, consistent with recovery of immunocompetence in protracted sepsis. Structurally distinct T_H2-polarizing agonists varied in their ability to replace OCH as the initial hit, with their lipid chain length being a determinant of efficacy. The proposed approach effectively exploits iNKT cells' versatility in biphasic sepsis and may have translational potentials in the development of new therapies.

Eosinophil count (EC) as a diagnostic and prognostic marker for infection in the internal medicine department setting

INTRODUCTION

Eosinopenia has been previously investigated as a marker to differentiate infectious from non-infectious diagnoses and as a prognostic marker. Most previous studies were conducted in intensive care unit patients. Our study focuses on the value of eosinopenia in patients admitted to the Internal Medicine department.

METHODS

We retrospectively analyzed 271 consecutive patients with infection and 31 patients presenting with fever or inflammatory syndrome and a non-infectious diagnosis. We evaluated and compared the following markers for differentiating infectious from non-infectious diagnoses: eosinophil count [EC], CRP, WBC and neutrophil-to-lymphocyte count ratio [NLCR]. We also evaluated the value of eosinopenia as a monitoring parameter in patients with infections.

RESULTS

Eosinopenia at admission was found in 71% of patients with infection compared to 32% in the non-infection group. EC and NLCR were moderate markers for discriminating infection from non-infection, with an area under the receiver operating characteristic curve of 0.789 and 0.718 respectively. Significant eosinopenia (≤ 10/µL) had a high specificity (90%) for diagnosing infections. High EC at admission (> 400/µL) was rare in the infection group (1.5%), but not uncommon in the non-infection group (25.8%). Persistent eosinopenia was noted in non-survivors, compared to the rapid normalization of EC in survivors.

CONCLUSIONS

Among patients presenting with fever and/or high inflammatory markers a low EC is supportive of infection, while a high EC may suggest non-infectious diagnoses. The persistence/ resolution of eosinopenia may be a useful monitoring parameter to predict response to therapy.

TGFβ depletion does neither modulate acute E. coli-induced inflammatory immune responses nor impair the protective effect by chronic filarial infection

TGFβ is an anti-inflammatory molecule that suppresses pro-inflammatory immune responses. Previously, we demonstrated that chronic filarial infection has a beneficial impact on Escherichia coli-induced sepsis. In the present study, we investigated whether this protective effect is dependent on TGFβ signaling and whether depletion of TGFβ before E. coli challenge alters the early course of sepsis per se. In vivo depletion of TGFβ before E. coli challenge did not alter levels of pro-inflammatory cytokines/chemokines and did neither increase the bacterial burden nor worsen E. coli-induced hypothermia six hours post E. coli challenge. Similarly, in the co-infection model, despite TGFβ depletion, mice infected with the filarial nematode Litomosoides sigmodontis exhibited milder E. coli-induced hypothermia, reduced bacterial load and pro-inflammatory immune responses. Thus, we conclude that TGFβ is not essentially modulating the initial pro-inflammatory phase during sepsis and that the protective effect of a chronic filarial infection against sepsis is independent of TGFβ signaling.

Eosinopenia and post-hospital outcomes in critically ill non-cardiac vascular surgery patients

BACKGROUND AND AIMS

Eosinopenia is a marker for acute inflammation. We hypothesized that eosinopenia at Intensive Care Unit (ICU) admission in vascular surgery patients who receive critical care, would be associated with increased mortality following hospital discharge.

METHODS AND RESULTS

We performed a two-center observational cohort study of critically ill, non-cardiac adult vascular surgery patients who received treatment in Boston between 1997 and 2012 and survived hospital admission. The consecutive sample included 5083 patients (male 57%, white 82%, mean age [SD] 61.6 [17.4] years). The exposure was Absolute eosinophil count measured within 24 h of admission to the ICU and categorized as ≤10 cells/μL, 11-50 cells/μL, 51-100 cells/μL, 101-350 cells/μL (normal range), and >350 cells/μL. The primary outcome was all-cause mortality within 90 days of hospital discharge. The secondary outcome was discharge to home following hospitalization. 90-day post-discharge mortality was 6.7%, and 12.9% of patients were readmitted within 30 days. After multivariable adjustment, patients with eosinopenia (≤10 cells/μL) have a 90-day post-discharge mortality OR of 1.97 (95%CI 1.42, 2.73; P < 0.001) relative to patients with an absolute eosinophil count of 101-350 cells/μL. Further, after multivariable adjustment, patients with eosinopenia (≤10 cells/μL) have a 25% lower odds of discharge to home compared to patients with an absolute eosinophil count of 101-350 cells/μL [OR = 0.71 (CI 95% 0.59-0.85); P < 0.001].

CONCLUSION

Eosinopenia at ICU admission is a robust predictor of increased mortality and lower likelihood of discharge to home in vascular surgery patients treated with critical care who survive hospitalization.

Eosinopenia as a marker of diagnosis and prognostic to distinguish bacterial from aseptic meningitis in pediatrics

Procalcitonin (PCT) has proven its efficacy to distinguish bacterial from aseptic meningitis in children. Nevertheless, its use in routine is limited by its cost and availability, especially in low- and middle-income countries. It is now acknowledged that eosinopenia is a marker of infection and/or severity of the systemic inflammatory response. Although no study ever demonstrated that eosinopenia could differentiate bacterial from viral infection, we decided to conduct a study concerning meningitis in children. This bicentric and retrospective study was conducted between January 2012 and October 2018, in children hospitalized for meningitis. The white blood cell was systematically gathered at the admission to evaluate the eosinophil count. Characteristic data were compared between 2 groups: documented bacterial meningitis (DBP) and aseptic meningitis which includes documented viral meningitis (DVM) and non-documented meningitis (ND). Among 190 patients admitted for meningitis, 151 were analyzed, including DBM (n = 45), DVM (n = 73), and ND (n = 33) meningitis. Groups were comparable. Mean age was 33 ± 48 months with a sex ratio of 1.6. Mean of eosinophil count was 15 ± 34/mm³ in the DBM group versus 132 ± 167/mm³ for the aseptic meningitis group (p < 0.0001). Best threshold for the diagnosis of bacterial meningitis was an eosinophil count < 5/mm³ with a sensitivity of 80% and specificity of 73% and a likelihood ratio of 2.9. Eosinopenia seems to be a reliable and non-invasive marker of bacterial meningitis in pediatrics. The absence of extra cost makes it very interesting in low- and middle-income countries or when usual biomarkers such as PCT are unavailable.

White blood cell count and eosinopenia as valuable tools for the diagnosis of bacterial infections in the ED

Identifying an infection may be difficult in the ED. Neutrophilic leukocytosis is often used in the diagnosis of infection despite its lack of specificity in situations of stress. Our objective was to study the value of each parameter of the WBC count, in particular eosinopenia, to diagnose bacterial infections in the ED. We conducted a retrospective and observational study over a period of 6 months. All patients with one of the following diagnoses were eligible: pneumonia (9.9%), pyelonephritis (26.2%), prostatitis (8.4%), appendicitis (26.2%), cholecystitis (8.4%), and diverticular sigmoiditis (5%). A total of 466 infected patients were included for statistical analysis, and a control group of 466 uninfected patients was randomly selected in the same period of time. All leukocyte count parameters were significantly modified (p < 0.001) in the infected group compared with the control group. Neutrophils and total leukocytes remain the two most suitable parameters for the diagnosis of infections in the ED. Eosinopenia represented the most efficient parameter of the WBC count for the diagnosis of urinary and biliary tract infections. Deep eosinopenia presented a specificity of 94% for the diagnosis of infection. Any modification of the WBC count associated with an elevation of CRP (> 40 mg/L) or fever (> 38.5 °C) showed a high specificity for the diagnosis of infection. A careful analysis of the WBC count remains a valuable tool for the diagnosis of infection in the ED.

Predictive value of in-hospital white blood cell count in Chinese patients with triple-vessel coronary disease

Aims

The predictive value of white blood cells in triple-vessel coronary artery disease (TVD) remains unclear. This study aimed to examine the relationship between WBC counts and long-term prognosis of TVD.

Methods

A total of 8943 consecutive patients with triple-vessel coronary artery disease were enrolled from April 2004 to February 2011. The primary endpoint was all-cause death and the secondary endpoints were major adverse cardiovascular and cerebrovascular events (MACCEs; a composite of all-cause death, myocardial infarction or stroke).

Results

After a median of 7.5 years of follow-up, 7678 patients were included in the final analysis. Multivariable analysis showed that the white blood cell count was an independent predictor of death (hazard ratio: 1.04, p < 0.01) and MACCE (hazard ratio: 1.03, p = 0.02). In white blood cell differential analysis, increased monocytes (hazard ratio: 1.93, p = 0.001) and eosinophils (hazard ratio: 1.82, p < 0.01), and decreased lymphocytes (hazard ratio: 0.89, p = 0.02) were independent predictors of death. Increased monocytes (hazard ratio: 1.62, P = 0.002) and eosinophils (hazard ratio: 1.55, p < 0.01) were independent predictors of MACCE. A combination of monocyte, lymphocyte and eosinophil counts with the Synergy between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery (SYNTAX) score improved the predictive value for mortality (area under the curve from 0.569 to 0.611; integrated discrimination improvement = 0.012; net reclassification improvement = 0.299) and improved slightly with SYNTAX score II (all p < 0.05).

Conclusion

Total and differential white blood cell counts are independent prognostic factors of long-term mortality and MACCE in triple-vessel coronary artery disease. A combination of monocyte, lymphocyte and eosinophil counts improved the predictive value for mortality with the SYNTAX score, and improved it slightly with SYNTAX score II.

[Eosinopenia in 2018]

Since 1893, eosinopenia is a biological test to help a diagnosis of bacterial infection. Several publications have confirmed this hypothesis, particularly in the intensive care, pneumology and pediatric units. The value of this marker has been identified in vascular cerebral diseases and coronary bypass. Its contribution seems as relevant as procalcitonin, without extra cost. The diagnostic performance of this test was reinforced by a composite score (CIBLE score) that may improve its value in daily routine. Finally, monitoring eosinopenia appears to be a reliable mortality marker.

IL-33 receptor (ST2) deficiency downregulates myeloid precursors, inflammatory NK and dendritic cells in early phase of sepsis

BACKGROUND

Sepsis is a life-threatening disease mediated by profound disturbances in systemic inflammatory response to infection. IL-33 is multifunctional regulator of numerous aspects of innate and adaptive immune response. The aim of this article was to further evaluate the role of IL-33 receptor (ST2) in different pathways of innate immunity during early polymicrobial sepsis.

METHODS

Polymicrobial sepsis was induced using cecal ligation and puncture (CLP) model in ST2 deficient (ST2-/-) and wild type BALB/c mice. Peritoneal and spleen cells were isolated for further phenotyping. Apoptosis was determined by immunohistochemistry and flow cytometry.

RESULTS

Deletion of ST2 leads to increased susceptibility to early manifestations of sepsis as evaluated by clinical signs and survival. These are accompanied by decrease in the total number of neutrophils, eosinophils and mast cells in peritoneal cavity 12 h after CLP. In early sepsis there was also low number of precursors of myeloid cells in particular CD11b+Ly6G+Ly6Clow cells in spleen of ST2-/- mice. Although the number of NK cells in the spleen was similar, there were significant differences in the presence of inflammatory IFN-γ and IL-17 producing NK cells. Further, ST2 deletion affects the phenotype and maturation of dendritic cell in sepsis. The total number of dendritic cells in the spleen was lower as well as IL-12 expressing dendritic cells. Finally, there was higher frequency of active caspase-3 positive and early apoptotic cells, in particular CD11c positive cells, in spleen of septic ST2-/- mice.

CONCLUSION

Taken together, our data provide the evidence that ST2 deficiency in early phase of sepsis downregulates myeloid precursors, inflammatory NK and dendritic cells.

Pitfalls in studies of eosinopenia and neutrophil-to-lymphocyte count ratio

There is a number of publications evaluating the eosinophil count and the neutrophil-to-lymphocyte count ratio for diagnosis, prognosis or monitoring of patients. Of special interest is the use of these parameters for discrimination between the different causes of fever (e.g. bacterial versus viral vs. non-infectious causes of fever) and for monitoring the efficacy of therapy and predict the course of the patient. However, pitfalls in previous study designs prevent applicability to clinical practice. Here, we provide a short review of the relevant literature and summarize important factors that should be taken into account when designing studies, with special attention to the selection of a proper and clinically meaningful study population and the effects of the stress response and of corticosteroids.

[Relevance of eosinopenia as marker of sepsis in the Emergency Department]

BACKGROUND

Several studies in internal medicine departments and in intensive care units have shown the interest of eosinopenia in the diagnosis of infected patients. The aim of the present study was to test the value of this marker in the Emergency Department (ED), either alone or associated with other common sepsis markers.

METHODS

We report on a retrospective and monocentric study. We reviewed the complete blood count (CBC) of all patients visiting the ED during one-week duration (in February 2014). Every element of the CBC and other inflammation markers (such as CRP) were analyzed.

RESULTS

During the week of our study, 725 patients had a CBC (33 exclusions) and 692 patients were included for analysis. The median age was 59 years (IQR: 16-100). One hundred and twenty-five patients (18.1%) had a sepsis. The ROC curve demonstrated a cut off level of 10/mm³ eosinophils for which the specificity for sepsis was 91%. The association of eosinopenia (< 10/mm³) and white blood cells (WBC) or CRP elevation also showed a good specificity in patients with sepsis.

CONCLUSION

In the ED, with a "simple" CBC, a profound eosinopenia appears to be very specific for sepsis, alone or in association with other markers of inflammation. Eosinopenia may become a helpful tool in our daily practice in the ED. Further studies are needed to further evaluate this marker.

Evaluation of epidemiological and clinical features of influenza and other respiratory viruses

AIM

In our study, we aimed to clinically and epidemiologically evaluate respiratory tract infections the viral agents of which were detected by molecular methods and to compare influenza and other respiratory tract viruses in this context.

MATERIAL AND METHODS

The records of 178 patients aged above 2 years who presented to pediatric emergency outpatient clinic with fever and respiratory tract infection findings between December 2013 and April 2014 were examined retrospectively.

RESULTS

At least one respiratory tract pathogen was detected by polymerase chain reaction in 78.6% (n=140) of the patients: influenza A 33.5%, influenza B 16.4%, respiratory syncytial virus 9.2%, adenovirus 7.8%, rhinovirus 7.1%, coronavirus 7.1%, human metapneumovirus 5.7%, human bocavirus 5.7%, parainfluenza virus 3.5%, coinfection 2.8%. The mean age of the patients was 6.3±3.6 years. Sixty-nine patients (49.2%) were aged between 2 and 5 years. Seventy-one patients (50.7%) were aged 5 years and above. Upper respiratory tract infection was found with a rate of 65.7% and lower respiratory tract infection was found with a rate of 34.2%. It was observed that the distribution of respiratory tract viruses showed variance by age groups. Influenza A infection was observed with the highest rate in both age groups. Influenza B was the second leading agent (p=0.008) above the age of 5 years and respiratory syncytial virus was the second leading agent in the 2-5 year age group (p=0.003). Influenza viruses were detected in 55.9% of 118 patients who were found to be compatible with the definition of "influenza-like illness" specified in the Center for Disease Control and Prevention guidelines and other viral agenst were detected in 44%. No difference could be found between the clinical pictures and radiological findings caused by influenza and other respiratory tract viruses.

CONCLUSIONS

In this study, it was concluded that influenza and other respiratory viruses can not be differentiated definitely by clinical and radiological findings, though there are some differences.

Eosinophil count at intensive care unit admission was not predictor of hospital mortality: results of a case control study

Background

Predicting mortality in the intensive care unit (ICU) is one of the biggest challenges in critical care medicine. Several studies have linked the presence of eosinopenia with adverse outcomes in different populations.

Methods

We performed a case control study to determine whether the eosinophil count at ICU admission was a predictor of hospital mortality. We included data from patients 18 years or older admitted to the medical or surgical ICU in a university hospital in northern of Mexico. Medical records of 86 non-survivors (cases) and 99 discharged alive patients (controls) were randomly reviewed; clinical records of patients with an ICU stay of less than 24 h and those whose information was incomplete were excluded.

Results

Median of eosinophil count at ICU admission was 0.013 (interquartile range (IQR) 0.00 to 0.57) K/μL. There was no significant statistical difference in eosinophils at admission between survivors and non-survivors (0.014 [IQR 0.00 to 0.36] vs. 0.010 [IQR 0.00 to 0.57] K/μL, P = 0.35). In the multivariate analysis, APACHE II score at ICU admission and discharge were the only mortality predictors. Survivors had a significantly greater increase in eosinophil count during the first 7 days of ICU stay (0.104 [IQR −0.64 to 0.41] vs. 0.005 [IQR −1.79 to 0.43] K/μL, P = 0.004).

Conclusions

In our study, eosinophil count at ICU admission was not associated with increased hospital mortality. The larger increase in number of eosinophils observed during the first week of ICU stay in surviving patients deserves to be investigated further.

Staphylococcus aureus enterotoxins A and B inhibit human and mice eosinophil chemotaxis and adhesion in vitro

Staphylococcus aureus aggravates the allergic eosinophilic inflammation. We hypothesized that Staphylococcus aureus-derived enterotoxins directly affect eosinophil functions. Therefore, this study investigated the effects of Staphylococcal enterotoxins A and B (SEA and SEB) on human and mice eosinophil chemotaxis and adhesion in vitro, focusing on p38 MAPK phosphorylation and intracellular Ca(2+) mobilization. Eosinophil chemotaxis was evaluated using a microchemotaxis chamber, whereas adhesion was performed in VCAM-1 and ICAM-1-coated plates. Measurement of p38 MAPK phosphorylation and intracellular Ca(2+) levels were monitored by flow cytometry and fluorogenic calcium-binding dye, respectively. Prior incubation (30 to 240 min) of human blood eosinophils with SEA (0.5 to 3 ng/ml) significantly reduced eotaxin-, PAF- and RANTES-induced chemotaxis (P<0.05). Likewise, SEB (1 ng/ml, 30 min) significantly reduced eotaxin-induced human eosinophil chemotaxis (P<0.05). The reduction of eotaxin-induced human eosinophil chemotaxis by SEA and SEB was prevented by anti-MHC monoclonal antibody (1 μg/ml). In addition, SEA and SEB nearly suppressed the eotaxin-induced human eosinophil adhesion in ICAM-1- and VCAM-1-coated plates. SEA and SEB prevented the increases of p38 MAPK phosphorylation and Ca(2+) levels in eotaxin-activated human eosinophils. In separate protocols, we evaluated the effects of SEA on chemotaxis and adhesion of eosinophils obtained from mice bone marrow. SEA (10 ng/ml) significantly reduced the eotaxin-induced chemotaxis along with cell adhesion to both ICAM-1 and VCAM-1-coated plates (P<0.05). In conclusion, the inhibition by SEA and SEB of eosinophil functions (chemotaxis and adhesion) are associated with reductions of p38 MAPK phosphorylation and intracellular Ca(2+) mobilization.

U-shape relationship of white blood cells with acute kidney injury and mortality in critically ill patients

Low or high counts of white blood cells (WBCs) and WBC subtypes can be a predictor of morbidity and mortality in several clinical settings. However, the correlations of WBC and its subtypes with acute kidney injury (AKI) and mortality remain unresolved in critically ill patients. The counts of WBC and subtypes, such as neutrophil, lymphocyte, monocyte, and eosinophil, were measured in 2,079 patients admitted to the intensive care unit (ICU) from June 2004 through June 2010. The non-linear relationship between WBC counts and AKI risk was initially explored by a restricted cubic spline analysis. The odds ratios (ORs) for AKI and 1-year mortality were calculated after adjustment for multiple covariates. The relationship between WBC counts and AKI risk was U-shaped. Accordingly, we divided patients into quintiles according to the counts of WBC or subtypes. The 1(st) and 5(th) quintiles of WBC counts had greater ORs for AKI (1.42 and 2.05, respectively) and mortality (1.40 and 1.36, respectively) compared with the 3(rd) quintile. After stratification by WBC subtype, the 5(th) quintile of neutrophil counts and the 1(st) quintiles of lymphocyte and monocyte counts tended to have higher ORs for AKI (1.69, 1.40, and 1.77, respectively). For mortality, the 1(st) quintiles of neutrophil, lymphocyte, and eosinophil counts were associated with higher mortality compared with the 3(rd) quintile (the ORs were 1.48, 1.57, and 1.42, respectively). Both leukopenia and leukocytosis are associated with AKI and mortality risk in critically ill patients. This result may be attributable to the change in the subtype counts.

Biomarkers in sepsis

There is much enthusiasm and interest in sepsis biomarkers, particularly because sepsis is a highly lethal condition, its diagnosis is challenging, and even simple treatment with antibiotics has led to serious adverse consequences such as emergence of resistant pathogens. Yet development of a sepsis biomarker requires many more steps than simply finding an association between a particular molecule and a clinical state or outcome. Demonstration of improvement of therapeutic practice using receiver-operating characteristic and other analyses is important. Validation in independent, prospective and, preferably, multicenter trials is essential. Many promising candidate sepsis biomarkers have recently been proposed. While procalcitonin (PCT) is currently the most studied sepsis biomarker, evidence of potential value has been found for a wide array of blood biomarkers including proteins, mRNA expression in whole blood or leukocytes, micro-RNAs (miRNA), pathogen and host DNA, pathogen and host genetic variants and metabolomic panels, and even in the novel use of currently available clinical data. While the most common early reports link putative sepsis biomarker levels to severity of illness and outcome (prognostic), this is not anticipated to be their primary use. More important is the distinction between infection and noninfectious inflammatory responses (diagnostic) and the use of sepsis biomarkers to direct therapy (predictive).

Eosinophil as a protective cell in S. aureus ventilator-associated pneumonia

Cell counts of leukocytes subpopulations are demonstrating to have an important value in predicting outcome in severe infections. We evaluated here the render of leukogram counts to predict outcome in patients with ventilator-associated pneumonia (VAP) caused by Staphylococcus aureus. Data from patients admitted to the ICU of Hospital Clínico Universitario de Valladolid from 2006 to 2011 with diagnosis of VAP caused by S. aureus were retrospectively collected for the study (n = 44). Leukocyte counts were collected at ICU admission and also at VAP diagnosis. Our results showed that nonsurvivors had significant lower eosinophil counts at VAP diagnosis. Multivariate Cox regression analysis performed by the Wald test for forward selection showed that eosinophil increments from ICU admission to VAP diagnosis and total eosinophil counts at VAP diagnosis were protective factors against mortality in the first 28 days following diagnosis: (HR [CI 95%], P): (0.996 [0.993–0.999], 0.010); (0.370 [0.180–0.750], 0.006). Patients with eosinophil counts <30 cells/mm³ at diagnosis died earlier. Eosinophil counts identified survivors: (AUROC [CI 95%], P): (0.701 [0.519–0.882], 0.042). Eosinophil behaves as a protective cell in patients with VAP caused by S. aureus.

Prognostic usefulness of eosinopenia in the pediatric intensive care unit

Eosinopenia, a biomarker for infection, has recently been shown to be a predictor of adult mortality in the intensive care unit (ICU). Our study assessed the usefulness of eosinopenia as a mortality and an infection biomarker in the pediatric ICU (PICU). We compared the PICU mortality scores, eosinophil count and percentage at ICU admission between children who survived and those who did not survive and between children with infection and those without infection. A total of 150 patients were evaluated. The initial eosinophil count and percentage were significantly lower in the group that did not survive when compared to those that did survive (P < 0.001; P < 0.001). However, there was no significant difference in the eosinophil count and percentage seen in patients with and without infection. Eosinopenia, defined as an eosinophil count < 15 cells/µL and an eosinophil percentage < 0.25%, (hazard ratio [HR]: 2.96; P = 0.008) along with a Pediatric Index of Mortality (PIM) 2 (HR: 1.03; P = 0.004) were both determined to be independent predictors of mortality in the PICU. The presence of eosinopenia at the ICU admission can be a useful biomarker for mortality in children, but is not useful as a biomarker for infection.