Interleukin 6, galectin 3, growth differentiation factor 15, and soluble ST2 for mortality prediction in critically ill patients

Therapeutic plasma exchange is feasible and tolerable in severely injured patients with trauma-induced coagulopathy

Objectives

Trauma-induced coagulopathy (TIC) occurs in a subset of severely injured trauma patients. Despite having achieved surgical hemostasis, these individuals can have persistent bleeding, clotting, or both in conjunction with deranged coagulation parameters and typically require transfusion support with plasma, platelets, and/or cryoprecipitate. Due to the multifactorial nature of TIC, targeted interventions usually do not have significant clinical benefits. Therapeutic plasma exchange (TPE) is a non-specific modality of removing and replacing a patient's plasma in a euvolemic manner that can temporarily normalize coagulation parameters and remove deleterious substances, and may be beneficial in such patients with TIC.

Methods

In a prospective case series, TPE was performed in severely injured trauma patients diagnosed with TIC and transfusion requirement. These individuals all underwent a series of at least 3 TPE procedures performed once daily with plasma as the exclusive replacement fluid. Demographic, injury, laboratory, TPE, and outcome data were collected and analyzed.

Results

In total, 7 patients received 23 TPE procedures. All patients had marked improvements in routine coagulation parameters, platelet counts, a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13 (ADAMTS13) activities, inflammatory markers including interleukin-6 concentrations, and organ system injuries after completion of their TPE treatments. All-cause mortality rates at 1 day, 7 days, and 30 days were 0%, 0%, and 43%, respectively, and all patients for whom TPE was initiated within 24 hours after injury survived to the 30-day timepoint. Surgical, critical care, and apheresis nursing personnel who were surveyed were universally positive about the utilization of TPE in this patient population. These procedures were tolerated well with the most common adverse event being laboratory-diagnosed hypocalcemia.

Conclusion

TPE is feasible and tolerable in severely injured trauma patients with TIC. However, many questions remain regarding the application of TPE for these critically ill patients including identification of the optimal injured population, ideal time of treatment initiation, appropriate treatment intensity, and concurrent use of adjunctive treatments.

Level of evidence

Level V.

A scoping review considering potential biomarkers or functional measures of gastrointestinal dysfunction and enteral feeding intolerance in critically ill adults

BACKGROUND & AIM

Enteral feeding intolerance (EFI) as a result of gastrointestinal (GI) dysfunction in critically ill adults can lead to suboptimal nutritional delivery, increasing the risk of hospital acquired malnutrition. There are no validated measures of EFI or consensus as to which measures could be used to define EFI. The aim of this scoping review is to explore the validity of biomarkers, physiological or functional measures of GI dysfunction and EFI in critically ill adults characterising their use in routine clinical practice to identify those with GI dysfunction to better guide nutritional support.

METHODS

Database searches were completed in Ovid MEDLINE, Embase, CINAHL and Web of Science using the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) guidelines. The search was performed until June 2022. Articles were included if they reported original studies that identify potential biomarkers or functional measures of EFI in critically ill adults. A nine-stage process was completed to extract and complete data synthesis.

RESULTS

139 unique articles were identified. Following review of titles and abstracts, 114 of these articles were excluded, three further articles were excluded after full text review and 22 articles met the inclusion criteria. A thematic analysis of the articles included identified three overarching themes of GI dysfunction: (1) Serum biomarkers, (2) Physiological markers, and (3) Functional markers. Within the category of serum biomarkers, a further three sub-categories were identified: (i) enterohormones, (ii) markers of enterocyte function, and iii) cytokines and neurotransmitters. Some associations were seen between EFI and heparin binding protein, intra-abdominal pressure, cholecystokinin and acetylcholine levels but no markers are currently suitable for daily clinical use.

CONCLUSIONS

Further larger studies are required to characterise the relationships between serum biomarkers, physiological and functional makers of GI dysfunction in critically ill adults. A robust definition of GI dysfunction should be included in any future research.

Interleukin-33/ Suppression of Tumorigenicity 2 in Renal Fibrosis: Emerging Roles in Prognosis and Treatment

Chronic kidney disease (CKD) is a major public health problem that affects more than 10% of the population worldwide and has a high mortality rate. Therefore, it is necessary to identify novel treatment strategies for CKD. Incidentally, renal fibrosis plays a central role in the progression of CKD to end-stage renal disease (ESRD). The activation of inflammatory pathways leads to the development of renal fibrosis. In fact, interleukin-33 (IL-33), a newly discovered member of the interleukin 1 (IL-1) cytokine family, is a crucial regulator of the inflammatory process. It exerts pro-inflammatory and pro-fibrotic effects via the suppression of tumorigenicity 2 (ST2) receptor, which, in turn, activates other inflammatory pathways. Although the role of this pathway in cardiac, pulmonary, and hepatic fibrotic diseases has been extensively studied, its precise role in renal fibrosis has not yet been completely elucidated. Recent studies have shown that a sustained activation of IL-33/ST2 pathway promotes the development of renal fibrosis. However, with prolonged research in this field, it is expected that the IL-33/ST2 pathway will be used as a diagnostic and prognostic tool for renal diseases. In addition, the IL-33/ST2 pathway seems to be a new target for the future treatment of CKD. Here, we review the mechanisms and potential applications of the IL-33/ST2 pathway in renal fibrosis; such that it can help clinicians and researchers to explore effective treatment options and develop novel medicines for CKD patients.

Soluble ST2 and All-Cause Mortality in Patients with Chronic Obstructive Pulmonary Disease—A 10-Year Cohort Study

Chronic obstructive pulmonary disease (COPD) is an inflammatory condition with constantly increasing mortality rates. Interleukin (IL)-33 and its decoy receptor, soluble suppression of tumorigenicity 2 (sST2), play a central role in the inflammatory response during infection. sST2 was suggested as a factor in the pathogenesis of COPD and emerged as a predictor of mortality in other non-communicable diseases. The role of sST2 as a predictor of mortality remains unclear in COPD yet. In this cohort study, we measured circulating concentrations of IL-33 and sST2 in the serum of patients with stable COPD (n = 59), patients with acute exacerbation of COPD (n = 29) and smoking (n = 20) and non-smoking controls (n = 20), using commercially available ELISAs, and investigated the prognostic role of sST2 in stable COPD. sST2 levels were significantly higher in COPD patients and smokers compared with non-smoking controls. We identified systolic blood pressure, forced expiratory volume in 1 s (FEV1% predicted), neutrophil count, lactate dehydrogenase and pack-years index as independent predictors of sST2 levels. During a median follow-up time of 10.6 years, 28 patients (47.5%) died. sST2 was an independent predictor of all-cause mortality in patients with COPD with a hazard ratio of 2.9 (95% CI 1.1–8.4, p = 0.035) per one standard deviation after adjustment for age, sex, pack-years, FEV1% predicted and C-reactive protein (CRP). sST2 concentrations are associated with severity of disease and long-term outcome in patients with COPD.

Risk prediction of biomarkers for early multiple organ dysfunction in critically ill patients

Background

Shock and organ damage occur in critically ill patients in the emergency department because of biological responses to invasion, and cytokines play an important role in their development. It is important to predict early multiple organ dysfunction (MOD) because it is useful in predicting patient outcomes and selecting treatment strategies. This study examined the accuracy of biomarkers, including interleukin (IL)-6, in predicting early MOD in critically ill patients compared with that of quick sequential organ failure assessment (qSOFA).

Methods

This was a multicenter observational sub-study. Five universities from 2016 to 2018. Data of adult patients with systemic inflammatory response syndrome who presented to the emergency department or were admitted to the intensive care unit were prospectively evaluated. qSOFA score and each biomarker (IL-6, IL-8, IL-10, tumor necrosis factor-α, C-reactive protein, and procalcitonin [PCT]) level were assessed on Days 0, 1, and 2. The primary outcome was set as MOD on Day 2, and the area under the curve (AUC) was analyzed to evaluate qSOFA scores and biomarker levels.

Results

Of 199 patients, 38 were excluded and 161 were included. Patients with MOD on Day 2 had significantly higher qSOFA, SOFA, and Acute Physiology and Chronic Health Evaluation II scores and a trend toward worse prognosis, including mortality. The AUC for qSOFA score (Day 0) that predicted MOD (Day 2) was 0.728 (95% confidence interval [CI]: 0.651–0.794). IL-6 (Day 1) showed the highest AUC among all biomarkers (0.790 [95% CI: 0.711–852]). The combination of qSOFA (Day 0) and IL-6 (Day 1) showed improved prediction accuracy (0.842 [95% CI: 0.771–0.893]). The combination model using qSOFA (Day 1) and IL-6 (Day 1) also showed a higher AUC (0.868 [95% CI: 0.799–0.915]). The combination model of IL-8 and PCT also showed a significant improvement in AUC.

Conclusions

The addition of IL-6, IL-8 and PCT to qSOFA scores improved the accuracy of early MOD prediction.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12873-021-00534-z.

Galectin-3 in Critically Ill Patients with Sepsis and/or Trauma: A Good Predictor of Outcome or Not?

Severe sepsis and/or trauma complicated with multiple organ dysfunction syndrome are leading causes of death in critically ill patients. The aim of this prospective, observational, single centre study was to assess the prognostic value of galectin-3 regarding outcome in critically ill patients with severe trauma and/or severe sepsis. The outcome measure was hospital mortality.

In total, 75 critically ill patients who were admitted to the intensive care unit of the tertiary university hospital were enrolled in a prospective observational study. Blood samples were collected upon fulfilling Sepsis-3 criteria and for a traumatized Injury Severity Score > 25 points.

Levels of galectin-3 were significantly higher in nonsurvivors on the day of enrolment – Day 1 (p<0.05). On Day 1, the area under the curve (AUC) for the galectin-3 for lethal outcome was 0.602. At a cut-off level of 262.82 ng/mL, the sensitivity was 53%, and the specificity was 69.7%, which was objectively determined by a Youden index of 0.20.

The discriminative power of galectin-3 in predicting outcome was statistically significant. Galectin-3 on Day 1 is a fairly good predictor of lethal outcome.

Accuracy for Mortality Prediction With Additive Biomarkers Including Interleukin-6 in Critically Ill Patients: A Multicenter Prospective Observational Study

OBJECTIVES

Several inflammation markers have been reported to be associated with unfavorable clinical outcomes in critically ill patients. We aimed to elucidate whether serum interleukin-6 concentration considered with Sequential Organ Failure Assessment score can better predict mortality in critically ill patients.

DESIGN

A prospective observational study.

SETTING

Five university hospitals in 2016-2018.

PATIENTS

Critically ill adult patients who met greater than or equal to two systemic inflammatory response syndrome criteria at admission were included, and those who died or were discharged within 48 hours were excluded.

INTERVENTIONS

Inflammatory biomarkers including interleukin (interleukin)-6, -8, and -10; tumor necrosis factor-α; C-reactive protein; and procalcitonin were blindly measured daily for 3 days. Area under the receiver operating characteristic curve for Sequential Organ Failure Assessment score at day 2 according to 28-day mortality was calculated as baseline. Combination models of Sequential Organ Failure Assessment score and additional biomarkers were developed using logistic regression, and area under the receiver operating characteristic curve calculated in each model was compared with the baseline.

MEASUREMENTS AND MAIN RESULTS

Among 161 patients included in the study, 18 (11.2%) did not survive at day 28. Univariate analysis for each biomarker identified that the interleukin-6 (days 1-3), interleukin-8 (days 0-3), and interleukin-10 (days 1-3) were higher in nonsurvivors than in survivors. Analyses of 28-day mortality prediction by a single biomarker showed interleukin-6, -8, and -10 at days 1-3 had a significant discrimination power, and the interleukin-6 at day 3 had the highest area under the receiver operating characteristic curve (0.766 [0.656-0.876]). The baseline area under the receiver operating characteristic curve for Sequential Organ Failure Assessment score predicting 28-day mortality was 0.776 (0.672-0.880). The combination model using additional interleukin-6 at day 3 had higher area under the receiver operating characteristic curve than baseline (area under the receiver operating characteristic curve = 0.844, area under the receiver operating characteristic curve improvement = 0.068 [0.002-0.133]), whereas other biomarkers did not improve accuracy in predicting 28-day mortality.

CONCLUSIONS

Accuracy for 28-day mortality prediction was improved by adding serum interleukin-6 concentration to Sequential Organ Failure Assessment score.

Galectin-3 in septic acute kidney injury: a translational study

BACKGROUND

Galectin-3 (Gal-3) is a pleiotropic glycan-binding protein shown to be involved in sepsis and acute kidney injury (AKI). However, its role has never been elucidated in sepsis-associated AKI (S-AKI). We aimed to explore Gal-3's role and its potential utility as a therapeutic target in S-AKI.

METHODS

In 57 patients admitted to the intensive care unit (ICU) with sepsis, serum Gal-3 was examined as a predictor of ICU mortality and development of AKI. In a rat model of S-AKI induced by cecal ligation and puncture (CLP), 7-day mortality and serum Gal-3, Interleukin-6 (IL-6), and creatinine were examined at 2, 8, and 24 hours (h) post-CLP. Two experimental groups received the Gal-3 inhibitor modified citrus pectin (P-MCP) at 400 mg/kg/day and 1200 mg/kg/day, while the control group received water only (n = 18 in each group).

RESULTS

Among 57 patients, 27 developed AKI and 8 died in the ICU. Serum Gal-3 was an independent predictor of AKI (OR = 1.2 [95% CI 1.1-1.4], p = 0.01) and ICU mortality (OR = 1.4 [95% CI 1.1-2.2], p = 0.04) before and after controlling for age, AKI, and acute physiology and chronic health evaluation (APACHE II) score. In the CLP rat experiment, serum Gal-3 peaked earlier than IL-6. Serum Gal-3 was significantly lower in both P-MCP groups compared to control at 2 h post-CLP (400 mg: p = 0.003; 1200 mg: p = 0.002), and IL-6 was significantly lower in both P-MCP groups at all time points with a maximum difference at 24 h post-CLP (400 mg: p = 0.015; 1200 mg: p = 0.02). In the Gal-3 inhibitor groups, 7-day mortality was significantly reduced from 61% in the control group to 28% (400 mg P-MCP: p = 0.03) and 22% (1200 mg P-MCP: p = 0.001). Rates of AKI per RIFLE criteria were significantly reduced from 89% in the control group to 44% in both P-MCP groups (400 mg: p = 0.007; 1200 mg: p = 0.007).

CONCLUSIONS

This translational study demonstrates the importance of Gal-3 in the pathogenesis of S-AKI, and its potential utility as a therapeutic target.

Prognostic Value of Immunosuppressive Acidic Protein and Oxidative Stress Status in Critically Ill Patients

Introduction

The aim of this study was to determine the prognostic value of admission immunosuppressive acidic protein (IAP), interleukin-6 (IL-6), total oxidant status (TOS), and total antioxidant status (TAS) in 161 critically ill patients.

Materials and methods

This prospective observational study was carried out in the Emergency Department ICU for 6 months. Critically ill patients were included in the study consecutively. The main outcomes were the need for early mechanical ventilation (MV) and in-hospital mortality.

Results

The mean age of 161 patients was 66.5 ± 17.1 years. The median IL-6 levels of patients who required early MV were significantly higher than of the patients who required no MV (p < 0.001), and the median IL-6 levels in the nonsurvivors were significantly higher than in the survivors (p < 0.001). The median IAP levels were not significantly different between the groups (p = 0.464 for early MV and p = 0.340 for the in-hospital mortality group). The AUCs of IL-6 and TOS for predicting in-hospital mortality were 0.819 and 0.608, respectively.

Conclusion

The IAP level on admission to ICU is ineffective in predicting the need for early MV and in-hospital mortality; however, IL-6 level on admission is a strong prognostic predictor in critically ill patients. Our findings showed that the burden of oxidative stress was high in general ICU patients.

Clinical significance

Our study showed that increased oxidative stress is an important problem in critically ill patients. If measures are taken to reduce oxidative stress by physicians, the prognosis of critically ill patients will be better.

How to cite this article

Tutuncu EO, Dundar ZD, Kilinc I, Tutuncu A, Kocak S, Girisgin AS. Prognostic Value of Immunosuppressive Acidic Protein and Oxidative Stress Status in Critically Ill Patients. Indian J Crit Care Med 2021;25(4):405–410.

The clinical potential of GDF15 as a "ready-to-feed indicator" for critically ill adults

Background

Circulating growth-differentiation factor-15 (GDF15), a cellular stress marker, abruptly increases during critical illness, but its later time course remains unclear. GDF15 physiologically controls oral intake by driving aversive responses to nutrition. Early parenteral nutrition (PN) in ICU patients has overall been shown not beneficial. We hypothesized that low GDF15 can identify patients who benefit from early PN, tolerate enteral nutrition (EN), and resume spontaneous oral intake.

Methods

In secondary analyses of the EPaNIC-RCT on timing of PN initiation (early PN versus late PN) and the prospective observational DAS study, we documented the time course of circulating GDF15 in ICU (N = 1128) and 1 week post-ICU (N = 72), compared with healthy subjects (N = 65), and the impact hereon of randomization to early PN versus late PN in propensity score-matched groups (N = 564/group). Interaction between upon-admission GDF15 and randomization for its outcome effects was investigated (N = 4393). Finally, association between GDF15 and EN tolerance in ICU (N = 1383) and oral intake beyond ICU discharge (N = 72) was studied.

Results

GDF15 was elevated throughout ICU stay, similarly in early PN and late PN patients, and remained high beyond ICU discharge (p < 0.0001). Upon-admission GDF15 did not interact with randomization to early PN versus late PN for its outcome effects, but higher GDF15 independently related to worse outcomes (p ≤ 0.002). Lower GDF15 was only weakly related to gastrointestinal tolerance (p < 0.0001) and a steeper drop in GDF15 with more oral intake after ICU discharge (p = 0.05).

Conclusion

In critically ill patients, high GDF15 reflected poor prognosis and may contribute to aversive responses to nutrition. However, the potential of GDF15 as “ready-to-feed indicator” appears limited.

Trial registration

ClinicalTrials.gov, NCT00512122, registered 31 July 2007, https://www.clinicaltrials.gov/ct2/show/NCT00512122 (EPaNIC trial) and ISRCTN, ISRCTN 98806770, registered 11 November 2014, http://www.isrctn.com/ISRCTN98806770 (DAS trial)

Intravenous Arginine Administration Benefits CD4+ T-Cell Homeostasis and Attenuates Liver Inflammation in Mice with Polymicrobial Sepsis

This study investigated the effects of a single dose of arginine (Arg) administration at the beginning of sepsis on CD4+ T-cell regulation and liver inflammation in C57BL/6J mice. Mice were divided into normal control (NC), sham (SH), sepsis saline (SS), and sepsis Arg (SA) groups. An inducible nitric oxide (NO) synthase (iNOS) inhibitor was administered to additional sepsis groups to evaluate the role of NO during sepsis. Sepsis was induced using cecal ligation and puncture (CLP). The SS and SA groups received saline or Arg (300 mg/kg body weight) via tail vein 1 h after CLP. Mice were euthanized at 12 and 24 h post-CLP. Blood, para-aortic lymph nodes, and liver tissues were collected for further measurement. The findings showed that sepsis resulted in decreases in blood and para-aortic lymph node CD4+ T-cell percentages, whereas percentages of interleukin (IL)-4- and IL-17-expressing CD4+ T cells were upregulated. Compared to the SS group, Arg administration resulted in maintained circulating and para-aortic lymph node CD4+ T cells, an increased Th1/Th2 ratio, and a reduced Th17/Treg ratio post-CLP. In addition, levels of plasma liver injury markers and expression of inflammatory genes in liver decreased. These results suggest that a single dose of Arg administered after CLP increased Arg availability, sustained CD4+ T-cell populations, elicited more-balanced Th1/Th2/Th17/Treg polarization in the circulation and the para-aortic lymph nodes, and attenuated liver inflammation in sepsis. The favorable effects of Arg were abrogated when an iNOS inhibitor was administered, which indicated that NO may be participated in regulating the homeostasis of Th/Treg cells and subsequent liver inflammation during sepsis.

A novel urinary biomarker predicts 1-year mortality after discharge from intensive care

Rationale

The urinary proteome reflects molecular drivers of disease.

Objectives

To construct a urinary proteomic biomarker predicting 1-year post-ICU mortality.

Methods

In 1243 patients, the urinary proteome was measured on ICU admission, using capillary electrophoresis coupled with mass spectrometry along with clinical variables, circulating biomarkers (BNP, hsTnT, active ADM, and NGAL), and urinary albumin. Methods included support vector modeling to construct the classifier, Cox regression, the integrated discrimination (IDI), and net reclassification (NRI) improvement, and area under the curve (AUC) to assess predictive accuracy, and Proteasix and protein-proteome interactome analyses.

Measurements and main results

In the discovery (deaths/survivors, 70/299) and test (175/699) datasets, the new classifier ACM128, mainly consisting of collagen fragments, yielding AUCs of 0.755 (95% CI, 0.708–0.798) and 0.688 (0.656–0.719), respectively. While accounting for study site and clinical risk factors, hazard ratios in 1243 patients were 2.41 (2.00–2.91) for ACM128 (+ 1 SD), 1.24 (1.16–1.32) for the Charlson Comorbidity Index (+ 1 point), and ≥ 1.19 (P ≤ 0.022) for other biomarkers (+ 1 SD). ACM128 improved (P ≤ 0.0001) IDI (≥ + 0.50), NRI (≥ + 53.7), and AUC (≥ + 0.037) over and beyond clinical risk indicators and other biomarkers. Interactome mapping, using parental proteins derived from sequenced peptides included in ACM128 and in silico predicted proteases, including/excluding urinary collagen fragments (63/35 peptides), revealed as top molecular pathways protein digestion and absorption, lysosomal activity, and apoptosis.

Conclusions

The urinary proteomic classifier ACM128 predicts the 1-year post-ICU mortality over and beyond clinical risk factors and other biomarkers and revealed molecular pathways potentially contributing to a fatal outcome.

Association of Ang-2, vWF, and EVLWI with risk of mortality in sepsis patients with concomitant ARDS: A retrospective study

BACKGROUND/PURPOSE

This study aimed to determine the potential effects of angiopoietin-2 (Ang-2), von Willebrand factor (vWF), and extravascular lung water index (EVLWI) on the risk of mortality in sepsis patients with concomitant acute respiratory distress syndrome (ARDS).

METHODS

This retrospective study recruited 41 sepsis patients with concomitant ARDS from January 2015 to June 2018. Data of Ang-2 and vWF levels, EVLWI, and sequential organ failure assessment scores were collected at 0, 24, and 48 h after admission to the hospital.

RESULTS

The length of intensive care unit stay (P = 0.041) and Acute Physiology and Chronic Health Evaluation-2 (APACHE II) score (P = 0.003) were associated with the risk of mortality. Furthermore, increased Ang-2 levels and EVLWI at 24 h and 48 h were associated with an increased risk of mortality. Moreover, the APACHE II score at hospital admission significantly predicted the risk of mortality (area under the curve [AUC], 0.834; 95% confidence interval [CI], 0.665-0.983). Finally, the models containing a combination of Ang-2 level and EVLWI at 24 h (AUC, 0.908; 95% CI, 0.774-0.996) and Ang-2 level and EVLWI at 48 h (AUC, 0.981; 95% CI, 0.817-1.000) had high diagnostic values for predicting risk of mortality.

CONCLUSION

The study findings indicate that Ang-2 levels and EVLWI at 24 h and 48 h after admission are significantly associated with the risk of mortality.

Increased serum concentrations of soluble ST2 are associated with pulmonary complications and mortality in polytraumatized patients

BACKGROUND

We sought to evaluate the role of soluble ST2 (suppression of tumorigenicity) serum concentrations in polytraumatized patients and its potential role as biomarker for pulmonary complications.

METHODS

We included severely injured patients (injury severity score≥16) admitted to our level I trauma center and analyzed serum samples obtained on the day of admission and on day 2. Furthermore, patients with isolated thoracic injury and healthy probands were included and served as control groups. Serum samples were analyzed for soluble ST2 concentrations with a commercially available ELISA kit.

RESULTS

A total of 130 patients were included in the present study. Five patients with isolated thoracic injury and eight healthy probands were further included. Serum analyses revealed significantly elevated concentrations of soluble ST2 in polytraumatized patients compared to patients suffering from isolated thoracic trauma and healthy probands. In polytraumatized patients who developed pulmonary complications (acute respiratory distress syndrome and pneumonia) and in patients who died, significantly higher serum concentrations of soluble ST2 were found on day 2 (p<0.001). Serum concentrations of soluble ST2 on day 2 were of prognostic value to predict pulmonary complications in polytraumatized patients (area under the curve=0.720, 95% confidence interval=0.623-0.816). Concomitant thoracic trauma had no further impact on serum concentrations of soluble ST2.

CONCLUSIONS

Serum concentrations of soluble ST2 are upregulated following polytrauma. Increased concentrations were associated with worse outcome.

Biomarkers associated with 30-day readmission and mortality after pediatric congenital heart surgery

OBJECTIVES

Novel cardiac biomarkers serum (suppression of tumorigenicity [ST2]) and Galectin-3 may be associated with an increased likelihood of important events after cardiac surgery. Our objective was to explore the association between pre- and postoperative serum biomarker levels and 30-day readmission or mortality for pediatric patients.

METHODS

We prospectively enrolled pediatric patients <18 years of age who underwent at least one cardiac surgical operation at Johns Hopkins Children's Center from 2010 to 2014 (N = 162). Blood samples were collected immediately before surgery and at the end of bypass. We evaluated the association between pre- and postoperative Galectin-3 and ST2 with 30-day readmission or mortality, using backward stepwise logistic regression, adjusting for covariates based on the Society of Thoracic Surgeons (STS) Congenital Heart Surgery Mortality Risk Model.

RESULTS

In our cohort, 21 (12.9%) patients experienced readmission or mortality 30-days from discharge. Before adjustment, preoperative ST2 terciles demonstrated a strong association with readmission and/or mortality after surgery (OR: 2.58; 95% CI: 1.17-3.66 and OR: 4.37; 95% CI: 1.31-14.57). After adjustment for covariates based on the STS congenital risk model, Galectin-3 postoperative mid-tercile was significantly associated with 30-day readmission or mortality (OR: 6.17; 95% CI: 1.50-0.43) as was the highest tercile of postoperative ST2 (OR: 4.98; 95% CI: 1.06-23.32).

CONCLUSIONS

Elevated pre-and postoperative levels of ST2 and Galectin-3 are associated with increased risk of readmission or mortality after pediatric heart surgery. These clinically available biomarkers can be used for improved risk stratification and may guide improved patient care management.

Growth differentiation factor-15 and the risk of cardiovascular diseases and all-cause mortality: A meta-analysis of prospective studies

Background and Aim

Previous studies have documented that the association between growth differentiation factor‐15 (GDF‐15) the risk of patients with cardiovascular diseases (CVDs). In this meta‐analysis, our main objective is to explore the associations between GDF‐15 and the risk of CVD or all‐cause mortality.

Methods

PubMed and ISI Web of Science (up to January 2018) electronic databases were browsed for eligible studies. The studies provided relevant data depicted as hazard ratio (HR) with 95% confidence interval (CI), with regard to the association between GDF‐15 levels and subsequent risk of CVDs or all‐cause mortality. A random‐effect model was applied to pool the HR and 95% CI.

Results

Thirty‐one prospective studies met the eligibility criteria involving 53 706 subjects with 7020 adverse outcome events. It was concluded that GDF‐15 levels were associated with an incremental risk of CVDs or all‐cause mortality. Highest GDF‐15 category was associated with greater risk of cardiovascular mortality (HR, 2.66; 95% CI, 1.69‐3.63), all‐cause mortality (HR, 2.52; 95% CI, 2.06‐2.97), and complex adverse outcome (HR, 1.81; 95% CI, 1.42‐2.21). As each log‐unit increment in GDF‐15 concentration, the corresponding risk of adverse events also escalated, cardiovascular mortality (HR, 2.11; 95% CI, 1.57‐2.66), all‐cause mortality (HR, 2.70; 95% CI, 2.29‐3.12), and complex adverse outcome (HR, 1.96; 95% CI, 1.64‐2.29).

Conclusions

Judging from the results of the data analysis, GDF‐15 levels may increase the risk of CVDs or all‐cause mortality.

Association between serum levels of interleukin-6 on ICU admission and subsequent outcomes in critically ill patients with acute kidney injury

BACKGROUND

Exacerbated inflammatory response is considered one of the key elements of acute kidney injury (AKI). Interleukin-6 (IL-6) is an inflammatory cytokine that plays important roles in the inflammatory response and may be useful for predicting the clinical outcomes in patients with AKI. However, supporting evidence adapted to the current KDIGO criteria is lacking.

METHODS

AKI patients admitted to the ICU between Jan 2011 and Dec 2015 were retrospectively screened. Patients were assigned to three groups by admission IL-6 tertiles. Associations between IL-6 on ICU admission and in-hospital 90-day mortality, short-term/long-term renal function were analyzed.

RESULTS

Patients (n = 646) were divided into low (1.5-150.2 pg/mL), middle (152.0-1168 pg/mL), and high (1189-2,346,310 pg/mL) IL-6 on ICU admission groups. Patients in the high IL-6 group had higher in-hospital 90-day mortality (low vs. middle vs. high, P = 0.0050), lower urine output (low vs. middle vs. high, P < 0.0001), and an increased probability of persistent of anuria for ≥12 h (low vs. middle vs. high, P < 0.0001) within 72 h after ICU admission. In contrast, the high IL-6 group had a lower incidence of persistent AKI at 90 days after the ICU admission in survivors (low vs. middle vs. high, P = 0.013).

CONCLUSIONS

Serum levels of IL-6 on ICU admission may predict short-term renal function and mortality in AKI patients and were associated with renal recovery in survivors.

sST2 as a novel biomarker for the prediction of in-hospital mortality after coronary artery bypass grafting

Objectives: Soluble suppression of tumorigenicity 2 (sST2) biomarker is an emerging predictor of adverse clinical outcomes, but its prognostic value for in-hospital mortality after coronary artery bypass grafting (CABG) is not well understood. This study measured the association between operative sST2 levels and in-hospital mortality after CABG. Methods: A prospective cohort of 1560 CABG patients were analyzed from the Northern New England Cardiovascular Disease Study Group Biomarker Study. The primary outcome was in-hospital mortality after CABG surgery (n = 32). Results: After risk adjustment, patients in the third tercile of pre-, post- and pre-to-postoperative sST2 values experienced significantly greater odds of in-hospital death compared to patients in the first tercile of sST2 values. The addition of both postoperative and pre-to-postoperative sST2 biomarker significantly improved ability to predict in-hospital mortality status following CABG surgery, compared to using the EuroSCORE II mortality model alone, (c-statistic: 0.83 [95% CI: 0.75, 0.92], p value 0.0213) and (c-statistic: 0.83 [95% CI: 0.75, 0.92], p value 0.0215), respectively. Conclusion: sST2 values are associated with in-hospital mortality after CABG surgery and postoperative and pre-to-post operative sST2 values improve prediction. Our findings suggest that sST2 can be used as a biomarker to identify adult patients at greatest risk of in-hospital death after CABG surgery.

Increased serum concentrations of soluble ST2 predict mortality after burn injury

Background:

Large burn injuries induce a systemic response in affected patients. Soluble ST2 (sST2) acts as a decoy receptor for interleukin-33 (IL-33) and has immunosuppressive effects. sST2 has been described previously as a prognostic serum marker. Our aim was to evaluate serum concentrations of sST2 and IL-33 after thermal injury and elucidate whether sST2 is associated with mortality in these patients.

Methods:

We included 32 burn patients (total body surface area [TBSA] >10%) admitted to our burn intensive care unit and compared them to eight healthy probands. Serum concentrations of sST2 and IL-33 were measured serially using an enzyme-linked immunosorbent assay (ELISA) technique.

Results:

The mean TBSA was 32.5%±19.6%. Six patients (18.8%) died during the hospital stay. Serum analyses showed significantly increased concentrations of sST2 and reduced concentrations of IL-33 in burn patients compared to healthy controls. In our study cohort, higher serum concentrations of sST2 were a strong independent predictor of mortality.

Conclusions:

Burn injuries cause an increment of sST2 serum concentrations with a concomitant reduction of IL-33. Higher concentrations of sST2 are associated with increased in-hospital mortality in burn patients.

Growth Differentiation Factor-15 Is a Predictor of Mortality in Critically Ill Patients with Sepsis

Growth differentiation factor-15 (GDF-15) is a member of the transforming growth factor-β superfamily related to inflammation and macrophage activation. Serum concentrations of GDF-15 can predict poor survival in chronic diseases, but its role in sepsis is obscure. Therefore, we investigated GDF-15 as a prognostic biomarker in critically ill patients. We measured GDF-15 levels in 219 critically ill patients (146 with sepsis, 73 without sepsis) upon admission to the intensive care unit (ICU), in comparison to 66 healthy controls. GDF-15 levels were significantly increased in ICU patients compared to controls. GDF-15 was further increased in sepsis and showed a strong association with organ dysfunction (kidney, liver and lactate) and disease severity (APACHE II and SOFA score). High GDF-15 concentrations at admission independently predicted ICU (HR 3.42; 95% CI 1.33–8.78) and overall mortality (HR 2.02, 95% CI 1.02–3.88) in all ICU critically ill patients as well as in a large subgroup of sepsis patients (ICU mortality: HR 3.16; 95% CI 1.10–9.07; overall mortality: HR 2.62; 95% CI 1.14–6.02). Collectively, serum GDF-15 levels are significantly increased in critically ill patients, associated with sepsis, organ failure, and disease severity. High GDF-15 levels at ICU admission predict short- and long-term mortality risk.

Predictive value of low interleukin-33 in critically ill patients

Patients admitted to a medical intensive care unit (ICU) are characterized by an activated immune system and exhibit a high mortality rate irrespective of the underlying cause of admission. Interleukin (IL)-33 has been shown to be protective in experimental sepsis models and it has been demonstrated that circulating levels of its "decoy" receptor soluble ST2 (sST2) are associated with outcome in critically ill patients. The aim of the present study was to investigate whether circulating IL-33 is associated with 30-day mortality in patients admitted to a medical ICU. In this prospective, observational study, both IL-33 and sST2 levels were assessed in 223 consecutive patients at ICU admission using specific enzyme-linked immunosorbent assays (ELISAs). During the 30-day follow-up, 58 patients (26%) died. Circulating IL-33 was detectable in 166 patients and in 57 patients, serum IL-33 was below the detection limit. Both detectable IL-33 and sST2 below the median were strong predictors of survival in critically ill patients independent of acute physiology and chronic health evaluation II (APACHE II) score. IL-33 and sST2 predicted risk independent from each other. Patients with both, non-detectable levels of IL-33 and sST2 levels above the median, showed a dramatically increased mortality risk (HR 6.9 95% CI 3.0-16.2; p<0.001). Low levels of IL-33 and increased levels of sST2 predict mortality risk in critically ill patients independent from each other and APACHE II score. Both together showed additive predictive value suggesting a pathogenic role of the IL-33/ST2 system in critically ill patients.

Sepsis mortality score for the prediction of mortality in septic patients

PURPOSE

To derive a prediction equation for 30-day mortality in sepsis using a multi-marker approach and compare its performance to the Sequential Organ Failure Assessment (SOFA) score.

METHODS

This study included 159 septic patients admitted to an intensive care unit. Leukocytes count, procalcitonin (PCT), interleukin-6 (IL-6), and paraoxonase (PON) and arylesterase (ARE) activities of PON-1 were assayed from blood obtained on ICU presentation. Logistic regression was used to derive sepsis mortality score (SMS), a prediction equation describing the relationship between biomarkers and 30-day mortality.

RESULTS

The 30-day mortality rate was 28.9%. The SMS was [еlogit(p)/(1+еlogit(p))]×100; logit(p)=0.74+(0.004×PCT)+(0.001×IL-6)-(0.025×ARE)-(0.059×leukocytes count). The SMC had higher area under the receiver operating characteristic curve (95% Cl) than SOFA score [0.814 (0.736-0.892) vs. 0.767 (0.677-0.857)], but is not statistically significant. When the SMS was added to the SOFA score, prediction of 30-day mortality improved compared to SOFA score used alone [0.845 (0.777-0.899), p=0.022].

CONCLUSIONS

A sepsis mortality score using baseline leukocytes count, PCT, IL-6 and ARE was derived, which predicted 30-day mortality with very good performance and added significant prognostic information to SOFA score.

Multi-marker approach using procalcitonin, presepsin, galectin-3, and soluble suppression of tumorigenicity 2 for the prediction of mortality in sepsis

BACKGROUND

Biomarker could be objective and reliable tools to predict mortality in sepsis. We explored the prognostic utilities of emerging biomarkers in septic patients and questioned whether adding biomarkers to the clinical variables would improve the prediction of mortality in sepsis.

METHODS

This retrospective study included 157 septic patients (112 patients with sepsis; 45 patients with septic shock). Procalcitonin (PCT), presepsin, galectin-3, and soluble suppression of tumorigenicity 2 (sST2) concentrations were analyzed in relation to the 30-day all-cause mortality. Their value added on top of Sequential (Sepsis-related) Organ Failure Assessment (SOFA) score, high-sensitivity C-reactive protein, and white blood cells was also analyzed.

RESULTS

PCT could not predict 30-day mortality. Univariate hazard ratio [HR with 95% confidence interval (CI)] of the other dichotomized variables was: 1.33 (0.55-3.194) for presepsin; 7.87 (2.29-26.96) for galectin-3; 1.55 (0.71-3.38) for sST2; and 2.18 (1.01-4.75) for SOFA score. The risk of 30-day mortality increased stepwise as the number of biomarkers above optimal cutoff values increased, and the highest risk was observed when all four biomarkers and SOFA score increased (HR = 14.5). Multi-marker approach predicted 30-day mortality better than SOFA score [area under the curves (95% CI), 0.769 (0.695-0.833) vs. 0.615 (0.535-0.692)]. In reclassification analyses, adding biomarkers to clinical variables improved the prediction of mortality.

CONCLUSION

This study demonstrated a possible prognostic utility of PCT, presepsin, galectin-3, and sST2 in sepsis. Multi-marker approach could be beneficial for an optimized management of patients with sepsis.