Small nucleolar RNA networks are up-regulated during human anaphylaxis.

BACKGROUND: Anaphylaxis is a severe, potentially life-threatening allergic reaction driven primarily by the activation of mast cells. We still fail to understand factors underlying reaction severity. Furthermore, there is currently no reliable diagnostic test to confirm anaphylaxis in the emergency department (ED). OBJECTIVE: This study sought to explore gene expression changes associated with anaphylaxis severity in peripheral blood leucocytes and evaluate biomarker potential. METHODS: Microarray analysis (total RNA) was performed using peripheral blood samples from ED patients with moderate (n = 6) or severe (n = 12) anaphylaxis and sepsis (n = 20) at presentation (T0) and one hour later (T1). Results were compared between groups and healthy controls (n = 10 and n = 11 matched to anaphylaxis and sepsis patients, respectively). Changes in gene expression were determined using R programming language, and pathway analysis applied to explore biological processes and pathways associated with genes. Differentially expressed genes were validated in an independent cohort of anaphylaxis (n = 30) and sepsis (n = 20) patients, and healthy controls (n = 10), using quantitative reverse transcription-polymerase chain reaction (qRT-PCR). RESULTS: Significant up-regulation of small nucleolar RNAs (snoRNAs) was demonstrated in anaphylaxis compared to sepsis patients in the microarray cohort, at T0 and T1. qRT-PCR analysis of the validation cohort showed five genes: SNORD61, SNORD8, SNORD69, SNORD119 and HIST1H1D to be significantly up-regulated (adjusted p < 0.05) in severe anaphylaxis compared to sepsis. Seven genes (SNORD61, SNORD8, SCARNA21, SNORD69, SNORD110, SNORD119 and SNORD59A) were significantly up-regulated (adjusted p < 0.05) in severe anaphylaxis compared to healthy controls. CONCLUSION: This study demonstrates for the first time the unique involvement of snoRNAs in the pathogenesis of anaphylaxis and suggests they are not a general feature of systemic inflammation. Further investigation of snoRNA expression in anaphylaxis could provide insights into disease pathogenesis. CLINICAL RELEVANCE: SnoRNAs are up-regulated during acute anaphylaxis in humans and could potentially be used as biomarkers of severe anaphylaxis.

Prospective validation study of prognostic biomarkers to predict adverse outcomes in patients with COVID-19: a study protocol.

INTRODUCTION: Accurate triage is an important first step to effectively manage the clinical treatment of severe cases in a pandemic outbreak. In the current COVID-19 global pandemic, there is a lack of reliable clinical tools to assist clinicians to perform accurate triage. Host response biomarkers have recently shown promise in risk stratification of disease progression; however, the role of these biomarkers in predicting disease progression in patients with COVID-19 is unknown. Here, we present a protocol outlining a prospective validation study to evaluate the biomarkers' performance in predicting clinical outcomes of patients with COVID-19. METHODS AND ANALYSIS: This prospective validation study assesses patients infected with COVID-19, in whom blood samples are prospectively collected. Recruited patients include a range of infection severity from asymptomatic to critically ill patients, recruited from the community, outpatient clinics, emergency departments and hospitals. Study samples consist of peripheral blood samples collected into RNA-preserving (PAXgene/Tempus) tubes on patient presentation or immediately on study enrolment. Real-time PCR (RT-PCR) will be performed on total RNA extracted from collected blood samples using primers specific to host response gene expression biomarkers that have been previously identified in studies of respiratory viral infections. The RT-PCR data will be analysed to assess the diagnostic performance of individual biomarkers in predicting COVID-19-related outcomes, such as viral pneumonia, acute respiratory distress syndrome or bacterial pneumonia. Biomarker performance will be evaluated using sensitivity, specificity, positive and negative predictive values, likelihood ratios and area under the receiver operating characteristic curve. ETHICS AND DISSEMINATION: This research protocol aims to study the host response gene expression biomarkers in severe respiratory viral infections with a pandemic potential (COVID-19). It has been approved by the local ethics committee with approval number 2020/ETH00886. The results of this project will be disseminated in international peer-reviewed scientific journals.

Single high-sensitivity troponin levels to assess patients with potential acute coronary syndromes.

OBJECTIVE: We tested the hypothesis that patients with a potential acute coronary syndrome (ACS) and very low levels of high-sensitivity cardiac troponin I can be efficiently and safely discharged from the emergency department after a single troponin measurement. METHODS: This prospective cohort study recruited 2255 consecutive patients aged ≥18 years presenting to the Emergency Department, Royal Perth Hospital, Western Australia, with chest pain without high-risk features but requiring the exclusion of ACS. Patients were managed using a guideline-recommended pathway or our novel Single Troponin Accelerated Triage (STAT) pathway. The primary outcome was the percentage of patients discharged in <3 hours. Secondary outcomes included the duration of observation and death or acute myocardial infarction in the next 30 days. RESULTS: The study enrolled 1131 patients to the standard cohort and 1124 to the STAT cohort. Thirty-eight per cent of the standard cohort were discharged directly from emergency department compared with 63% of the STAT cohort (p<0.001). The median duration of observation was 4.3 (IQR 3.3-7.1) hours in the standard cohort and 3.6 (2.6-5.4) hours in the STAT cohort (p<0.001), with 21% and 38% discharged in <3 hours, respectively (p<0.001). No patients discharged directly from the emergency department died or suffered an acute myocardial infarction within 30 days in either cohort. CONCLUSIONS: Among low-risk patients with a potential ACS, a pathway which incorporates early discharge based on a single very low level of high-sensitivity cardiac troponin increases the proportion of patients discharged directly from the emergency department, reduces length of stay and is safe. TRIAL REGISTRATION NUMBER: ACTRN12618000797279.

Bolus therapy with 3% hypertonic saline or 0.9% saline in emergency department patients with suspected sepsis: A pilot randomised controlled trial.

OBJECTIVE AND DESIGN: Hypertonic saline administered during fluid resuscitation may mitigate endothelial glycocalyx (EG) shedding and inflammation. The objective of this pilot randomised controlled trial was to measure the effect of hypertonic saline, compared to isotonic saline, on biomarkers of EG shedding and inflammation in emergency department patients with suspected sepsis. METHODS: Patients received either 5 mL/kg of 3% saline (hypertonic group, n = 34) or 10 mL/kg of 0.9% saline (isotonic group, n = 31). Change in serum biomarker concentrations of syndecan-1, hyaluronan, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, interleukin-6, -8, -10, interferon-γ, neutrophil gelatinase-associated lipocalin and resistin were compared from baseline (T0) to after fluid (T1), 3 h (T3) and 12-24 h (T24) later, as was serum osmolality, using linear mixed effects models. RESULTS: The hypertonic group had significantly increased mean serum osmolality compared to the isotonic group at T1 (P < .001) and T3 (P = .004). Minor differences were found in some biomarker outcomes, including a decreased fold-change in syndecan-1 at T1 (P = .012) and in interleukin-10 at T24 (P = .006) in the isotonic group, compared to the hypertonic group. CONCLUSIONS: Although a single bolus of hypertonic saline increased serum osmolality, it did not reduce biomarkers of EG shedding or inflammation, compared to patients that received isotonic saline. TRIAL REGISTRATION: ANZCTR.org.au, ACTRN12611001021965, Registered on 23rd September 2011.

Near-infrared spectroscopy to predict organ failure and outcome in sepsis: the Assessing Risk in Sepsis using a Tissue Oxygen Saturation (ARISTOS) study.

OBJECTIVES: Sepsis is acute organ dysfunction in the setting of infection. An accurate diagnosis is important to guide treatment and disposition. Tissue oxygen saturation (StO2) can be estimated noninvasively by near-infrared spectroscopy (NIRS), and may be an indicator of microcirculatory dysfunction in early sepsis. We aimed to determine the utility of StO2 for sepsis recognition and outcome prediction among patients presenting to the emergency department (ED) with infection. PATIENTS AND METHODS: A multicentre, prospective, observational cohort study recruited patients who were being admitted to hospital with infection. StO2 was measured in the ED using a handheld NIRS device, Inspectra 300. Outcomes were sepsis, defined as an increase in sequential organ failure assessment score of at least 2 points within 72 h, and composite in-hospital mortality/ICU admission at least 3 days. RESULTS: A cohort of 323 participants, median age 64 (interquartile range: 47-77) years, was recruited at three Australian hospitals. 143 (44%) fulfilled the criteria for sepsis and 22 (7%) died within 30 days. The mean ± SD StO2 was 74 ± 8% in sepsis and 78 ± 7% in nonsepsis (P < 0.0001). StO2 correlated with the peak sequential organ failure assessment score (Spearman's ρ -0.27, P < 0.0001). Area under the receiver operating characteristic curve was 0.66 (95% confidence interval: 0.60-0.72) for sepsis and 0.66 (0.58-0.75) for the composite outcome. StO2 less than 75% had an odds ratio of 2.67 (1.45-4.94; P = 0.002), for the composite outcome compared with StO2 at least 75%. CONCLUSION: NIRS-derived StO2 correlates with organ failure and is associated with outcome in sepsis. However, its ability to differentiate sepsis among ED patients with infection is limited. NIRS cannot be recommended for this purpose.

Markers Involved in Innate Immunity and Neutrophil Activation are Elevated during Acute Human Anaphylaxis: Validation of a Microarray Study.

BACKGROUND: We have previously identified the upregulation of the innate immune response, neutrophil activation, and apoptosis during anaphylaxis using a microarray approach. This study aimed to validate the differential gene expression and investigate protein concentrations of "hub genes" and upstream regulators during anaphylaxis. METHODS: Samples were collected from patients with anaphylaxis on their arrival at the emergency department, and after 1 and 3 h. mRNA levels of 11 genes (interleukin-6 [IL-6], IL-10, oncostatin M [OSM], S100A8, S100A9, matrix metalloproteinase 9 [MMP9], FASL, toll-like receptor 4 [TLR4], MYD88, triggering receptor expressed on myeloid cells 1 [TREM1], and cluster of differentiation 64 [CD64]) were measured in peripheral blood leucocytes using qPCR. Serum protein concentrations were measured by ELISA or cytometric bead array for 6 of these candidates. RESULTS: Of 69 anaphylaxis patients enrolled, 36 (52%) had severe reactions, and 38 (55%) were female. Increases in both mRNA and protein of IL-10, S100A9, MMP9, and TREM1 were observed. OSM, S100A8, TLR4, and CD64 were upregulated and IL-6 protein concentrations were increased during anaphylaxis. Both FASL and soluble Fas ligand decreased during anaphylaxis. CONCLUSION: These results provide evidence for the involvement of innate immune pathways and myeloid cells during human anaphylaxis, validating previous microarray findings. Elevated S100A8, S100A9, TLR4, and TREM1 expression, and increased S100A9 and soluble TREM1 protein concentrations strongly suggest that neutrophils are activated during acute anaphylaxis.

Restricted fluid resuscitation in suspected sepsis associated hypotension (REFRESH): a pilot randomised controlled trial.

PURPOSE: To determine if a regimen of restricted fluids and early vasopressor compared to usual care is feasible for initial resuscitation of hypotension due to suspected sepsis. METHODS: A prospective, randomised, open-label, clinical trial of a restricted fluid resuscitation regimen in the first 6 h among patients in the emergency department (ED) with suspected sepsis and a systolic blood pressure under 100 mmHg, after minimum 1000 ml of IV fluid. Primary outcome was total fluid administered within 6 h post randomisation. RESULTS: There were 99 participants (50 restricted volume and 49 usual care) in the intention-to-treat analysis. Median volume from presentation to 6 h in the restricted volume group was 2387 ml [first to third quartile (Q1-Q3) 1750-2750 ml]; 30 ml/kg (Q1-Q3 32-39 ml/kg) vs. 3000 ml (Q1-Q3 2250-3900 ml); 43 ml/kg (Q1-Q3 35-50 ml/kg) in the usual care group (p < 0.001). Median duration of vasopressor support was 21 h (Q1-Q3 9-42 h) vs. 33 h (Q1-Q3 15-50 h), (p = 0.13) in the restricted volume and usual care groups, respectively. At 90-days, 4 of 48 (8%) in the restricted volume group and 3 of 47 (6%) in the usual care group had died. Protocol deviations occurred in 6/50 (12%) in restricted group and 11/49 (22%) in the usual care group, and serious adverse events in four cases (8%) in each group. CONCLUSIONS: A regimen of restricted fluids and early vasopressor in ED patients with suspected sepsis and hypotension appears feasible. Illness severity was moderate and mortality rates low. A future trial is necessary with recruitment of high-risk patients to determine effects on clinical outcomes in this setting.

Glycocalyx biomarker syndecan-1 is a stronger predictor of respiratory failure in patients with sepsis due to pneumonia, compared to endocan.

PURPOSE: Endocan, a component of the endothelial glycocalyx (EG), has been linked with respiratory failure in sepsis. This study explored the temporal patterns of three EG biomarkers, including endocan, and their relationships with inflammation and respiratory failure. MATERIALS AND METHODS: Plasma endocan, syndecan-1, and hyaluronan concentrations were measured in Emergency Department (ED) patients with sepsis due to pneumonia (n = 44) on ED arrival (T0), 1 h (T1), 3 h (T3) and 12-24 h (T24) later, with change over time tested using mixed regression models. Biomarker associations with inflammatory cytokine concentrations and with respiratory failure on days 1, 2 or 3, need for mechanical ventilation and 30-day mortality were also tested. RESULTS: Endocan concentration significantly decreased over time (T0-T24, P = 0.003) whereas both syndecan-1 (T0-T3, P = 0.010; T0-T24, P < 0.001) and hyaluronan (T0-T1, P = 0.010; T0-T3, P < 0.001; T0-T24, P = 0.003) significantly increased over time. Increased syndecan-1 was significantly correlated with neutrophil activation biomarkers and significantly increased the odds of respiratory failure (OR 1.18, 95% CI 1.05-1.33, P = 0.004), need for mechanical ventilation (OR 1.24, 95% CI 1.04-1.48, P = 0.014) and 30-day mortality (OR 1.29, 95% CI 1.07-1.55, P = 0.008). CONCLUSION: Syndecan-1, but not endocan, was associated with neutrophil activation and was the best EG biomarker predictor of adverse clinical outcomes.

Liberal Versus Restrictive Intravenous Fluid Therapy for Early Septic Shock: Rationale for a Randomized Trial.

Prompt intravenous fluid therapy is a fundamental treatment for patients with septic shock. However, the optimal approach for administering intravenous fluid in septic shock resuscitation is unknown. Two competing strategies are emerging: a liberal fluids approach, consisting of a larger volume of initial fluid (50 to 75 mL/kg [4 to 6 L in an 80-kg adult] during the first 6 hours) and later use of vasopressors, versus a restrictive fluids approach, consisting of a smaller volume of initial fluid (≤30 mL/kg [≤2 to 3 L]), with earlier reliance on vasopressor infusions to maintain blood pressure and perfusion. Early fluid therapy may enhance or maintain tissue perfusion by increasing venous return and cardiac output. However, fluid administration may also have deleterious effects by causing edema within vital organs, leading to organ dysfunction and impairment of oxygen delivery. Conversely, a restrictive fluids approach primarily relies on vasopressors to reverse hypotension and maintain perfusion while limiting the administration of fluid. Both strategies have some evidence to support their use but lack robust data to confirm the benefit of one strategy over the other, creating clinical and scientific equipoise. As part of the National Heart, Lung, and Blood Institute Prevention and Early Treatment of Acute Lung Injury Network, we designed a randomized clinical trial to compare the liberal and restrictive fluids strategies, the Crystalloid Liberal or Vasopressor Early Resuscitation in Sepsis trial. The purpose of this article is to review the current literature on approaches to early fluid resuscitation in adults with septic shock and outline the rationale for the upcoming trial.

Endothelial glycocalyx biomarkers increase in patients with infection during Emergency Department treatment.

PURPOSE: Endothelial glycocalyx (EG) shedding may promote organ failure in sepsis. This study describes temporal changes in EG biomarkers from Emergency Department (ED) arrival, and associations with clinical characteristics. MATERIALS AND METHODS: This prospective observational study included 23 patients with simple infection, 86 with sepsis and 29 healthy controls. Serum EG biomarkers included syndecan-1, syndecan-4 and hyaluronan. Samples were taken on enrolment in the ED (T0), 1 hour (T1), 3 hours (T3) and 12 to 24 hours (T24) later. RESULTS: Syndecan-1 concentration increased incrementally over time (T0-T24, both patient groups, P < .001) whereas hyaluronan concentration peaked at T3 (T0-T3, sepsis group, P < .001). Hyaluronan was positively associated with cumulative fluid volumes (P < .001) at T0, T1, and T3, independent of illness severity. Both syndecan-1 (OR 1.04, 95% CI 1.01-1.07, P = .017) and hyaluronan (OR 1.83, 95% CI 1.46-2.30, P < .001) were associated with organ failure, independent of age and comorbidity. Syndecan-4 concentration was not different between groups or over time. CONCLUSIONS: In contrast to previous ICU studies, EG biomarkers increased during the first 24 hours of sepsis treatment and were associated with fluid volumes and organ failure. Further investigation is required to determine if interventions delivered in the ED contribute to EG shedding.

REstricted Fluid REsuscitation in Sepsis-associated Hypotension (REFRESH): study protocol for a pilot randomised controlled trial.

BACKGROUND: Guidelines recommend an initial intravenous (IV) fluid bolus of 30 ml/kg isotonic crystalloid for patients with sepsis and hypotension. However, there is a lack of evidence from clinical trials to support this. Accumulating observational data suggest harm associated with the injudicious use of fluids in sepsis. There is currently equipoise regarding liberal or restricted fluid-volume resuscitation as first-line treatment for sepsis-related hypotension. A randomised trial comparing these two approaches is, therefore, justified. METHODS/DESIGN: The REstricted Fluid REsuscitation in Sepsis-associated Hypotension trial (REFRESH) is a multicentre, open-label, randomised, phase II clinical feasibility trial. Participants will be patients presenting to the emergency departments of Australian metropolitan hospitals with suspected sepsis and a systolic blood pressure of < 100 mmHg, persisting after a 1000-ml fluid bolus with isotonic crystalloid. Participants will be randomised to either a second 1000-ml fluid bolus (standard care) or maintenance rate fluid only, with the early commencement of a vasopressor infusion to maintain a mean arterial pressure of > 65 mmHg, if required (restricted fluid). All will receive further protocolised fluid boluses (500 ml or 250 ml, respectively), if required during the 6-h study period. The primary outcome measure is total volume administered in the first 6 h. Secondary outcomes include fluid volume at 24 h, organ support 'free days' to day 28, 90-day mortality, and a range of feasibility and process-of-care measures. Participants will also undergo serial measurement, over the first 24 h, of biomarkers of inflammation, endothelial cell activation and glycocalyx degradation for comparison between the groups. DISCUSSION: This is the first randomised trial examining fluid volume for initial resuscitation in septic shock in an industrialised country. A pragmatic, open-label design will establish the feasibility of undertaking a large, international, multicentre trial with sufficient power to assess clinical outcomes. The embedded biomarker study aims to provide mechanistic plausibility for a larger trial by defining the effects of fluid volume on markers of systemic inflammation and the vascular endothelium. TRIAL REGISTRATION: Australia and New Zealand Clinical Trials Registry, ID: ACTRN12616000006448. Registered on 12 January 2016.

Resistin and NGAL are associated with inflammatory response, endothelial activation and clinical outcomes in sepsis.

OBJECTIVE AND DESIGN: Resistin and neutrophil gelatinase-associated lipocalin (NGAL) are upregulated in circulating leucocytes in sepsis, but the significance of this is uncertain. We evaluated associations between Resistin and NGAL with endothelial cell activation and clinical outcomes in a prospective observational study in the Emergency Department (ED). METHODS: Serum levels of Resistin, NGAL, inflammatory cytokines (IL-6, IL-10) and soluble endothelial adhesion molecules (VCAM-1, ICAM-1) were measured at defined time points up to 24 h. Patterns and relationships between markers were investigated using linear mixed regression models. Predictive values for clinical outcomes for markers at enrollment were assessed by logistic regression and receiver operator characteristic (ROC) curves. RESULTS: 186 participants (89 septic-shock, 69 sepsis, 28 uncomplicated infection) were compared with 29 healthy controls. Median Resistin and NGAL were higher in uncomplicated infection compared to controls, and in septic shock compared to non-shock sepsis. Resistin and NGAL correlated with IL-6 and IL-10, with VCAM-1 and ICAM-1, and with organ failure. Resistin and NGAL were associated with septic shock but had limited predictive utility for mortality. CONCLUSION: Resistin and NGAL correlate with expression of endothelial cell adhesion molecules in sepsis. Further evaluation of the role of Resistin and NGAL in sepsis pathogenesis is warranted.

Near-infrared spectroscopy in the assessment of suspected sepsis in the emergency department.

BACKGROUND AND AIMS: The conventional approach to sepsis resuscitation involves early interventions targeting global oxygenation and macro-haemodynamic variables such as central venous and systemic arterial pressures. There is increasing recognition of the importance of microcirculatory changes in shock states, including sepsis, and the relationship of these to outcome. Near-infrared spectroscopy (NIRS) is a recently developed non-invasive technology that measures tissue oxygen saturations (StO2), which may be an indirect measure of the adequacy of the microcirculation. StO2 measurements, therefore, have the potential to identify patients who are at risk of progressing to organ dysfunction and could be used to guide resuscitation. This article reviews the current state of knowledge of NIRS in the setting of sepsis, examining its application, validity and prognostic value. METHODS: A search of the relevant literature was performed using Medline, Embase and Cochrane databases, and a qualitative analysis was undertaken. RESULTS: A limited number of observational studies, mostly conducted among patients with severe sepsis, have shown that NIRS may correlate with severity of illness but demonstrate a variable relationship between StO2 and outcome. CONCLUSIONS: Outstanding questions still remain as to whether NIRS can help to risk-stratify patients with suspected sepsis in the emergency department and the utility of StO2 as a resuscitation target.

Comparison of PIRO, SOFA, and MEDS scores for predicting mortality in emergency department patients with severe sepsis and septic shock.

OBJECTIVES: The Predisposition Insult Response and Organ failure (PIRO) scoring system has been developed for use in the emergency department (ED) to risk stratify sepsis cases, but has not been well studied among high-risk patients with severe sepsis and septic shock. The PIRO score was compared with the Sequential Organ Failure Assessment (SOFA) and Mortality in ED Sepsis (MEDS) scores to predict mortality in ED patients with features suggesting severe sepsis or septic shock in the ED. METHODS: This was an analysis of sepsis patients enrolled in a prospective observational ED study of patients presenting with evidence of shock, hypoxemia, or other organ failure. PIRO, MEDS, and SOFA scores were calculated from ED data. Analysis compared areas under the receiver operator characteristic (ROC) curves for 30-day mortality. RESULTS: Of 240 enrolled patients, final diagnoses were septic shock in 128 (53%), severe sepsis without shock in 70 (29%), and infection with no organ dysfunction in 42 (18%). Forty-eight (20%) patients died within 30 days of presentation. Area under the ROC curve (AUC) for mortality was 0.86 (95% confidence interval [CI] = 0.80 to 0.92) for PIRO, 0.81 (95% CI = 0.74 to 0.88) for MEDS, and 0.78 (95% CI = 0.71 to 0.87) for SOFA scores. Pairwise comparisons of the AUC were as follows: PIRO versus SOFA, p = 0.01; PIRO versus MEDS, p = 0.064; and MEDS versus SOFA; p = 0.37. Mortality increased with increasing PIRO scores: PIRO < 5, 0%; PIRO 5 to 9, 5%; PIRO 10 to 14, 5%; PIRO 15 to 19, 37%; and PIRO ≥ 20, 80% (p < 0.001). The MEDS score also showed increasing mortality with higher scores: MEDS < 5, 0%; MEDS 5 to 7, 12%; MEDS 8 to 11, 15%; MEDS 12 to 14, 48%; and MEDS > 15, 65% (p < 0.001). CONCLUSIONS: The PIRO model, taking into account comorbidities and septic source as well as physiologic status, performed better than the SOFA score and similarly to the MEDS score for predicting mortality in ED patients with severe sepsis and septic shock. These findings have implications for identifying and managing high-risk patients and for the design of clinical trials in sepsis.

Sustained elevation of resistin, NGAL and IL-8 are associated with severe sepsis/septic shock in the emergency department.

OBJECTIVE: To identify biomarkers which distinguish severe sepsis/septic shock from uncomplicated sepsis in the Emergency Department (ED). METHODS: Patients with sepsis underwent serial blood sampling, including arrival in the ED and up to three subsequent time points over the first 24 hours. Messenger RNA (mRNA) levels of 13 genes representing arms of the innate immune response, organ dysfunction or shock were measured in peripheral blood leucocytes using quantitative PCR, and compared with healthy controls. Serum protein concentrations of targets differentially expressed between uncomplicated sepsis and severe sepsis/septic shock were then measured at each time point and compared between the two patient groups. RESULTS: Of 27 participants (median age 66 years, (IQR 35, 78)), 10 had uncomplicated sepsis and 17 had sepsis with organ failure (14 septic shock; 3 had other sepsis-related organ failures). At the time of first sample collection in the ED, gene expression of Interleukin (IL)-10 and Neutrophil Gelatinase Associated Lipocalin (NGAL) were significantly higher in severe sepsis than uncomplicated sepsis. Expression did not significantly change over time for any target gene. Serum concentrations of IL-6, IL-8, IL-10, NGAL and Resistin were significantly higher in severe sepsis than uncomplicated sepsis at the time of first sample collection in the ED, but only IL-8, NGAL and Resistin were consistently higher in severe sepsis compared to uncomplicated sepsis at all time points up to 24 h after presentation. CONCLUSIONS: These mediators, produced by both damaged tissues and circulating leukocytes, may have important roles in the development of severe sepsis. Further work will determine whether they have any value, in addition to clinical risk parameters, for the early identification of patients that will subsequently deteriorate and/or have a higher risk of death.

Randomized controlled trial of intravenous antivenom versus placebo for latrodectism: the second Redback Antivenom Evaluation (RAVE-II) study.

STUDY OBJECTIVE: Latrodectism is the most important spider envenomation syndrome worldwide. There remains considerable controversy over antivenom treatment. We aimed to investigate whether antivenom resulted in resolution of pain and systemic effects in patients with latrodectism who received standardized analgesia. METHODS: In a multicenter randomized placebo-controlled trial of redback spider antivenom for latrodectism, 224 patients (>7 years) with a redback spider bite and severe pain, with or without systemic effects, were randomized to receive normal saline solution (placebo) or antivenom after receiving standardized analgesia. The primary outcome was a clinically significant reduction in pain 2 hours after trial medication compared with baseline. A second primary outcome for the subgroup with systemic features of envenomation was resolution of systemic features at 2 hours. Secondary outcomes were improved pain at 4 and 24 hours, resolution of systemic features at 4 hours, administration of opioid analgesics or unblinded antivenom after 2 hours, and adverse reactions. RESULTS: Two hours after treatment, 26 of 112 patients (23%) from the placebo arm had a clinically significant improvement in pain versus 38 of 112 (34%) from the antivenom arm (difference in favor of antivenom 10.7%; 95% confidence interval -1.1% to 22.6%; P=.10). Systemic effects resolved after 2 hours in 9 of 41 patients (22%) in the placebo arm and 9 of 35 (26%) in the antivenom arm (difference 3.8%; 95% confidence interval -15% to 23%; P=.79). There was no significant difference in any secondary outcome between antivenom and placebo. Acute systemic hypersensitivity reactions occurred in 4 of 112 patients (3.6%) receiving antivenom. CONCLUSION: The addition of antivenom to standardized analgesia in patients with latrodectism did not significantly improve pain or systemic effects.

Modified TIMI risk score cannot be used to identify low-risk chest pain in the emergency department: a multicentre validation study.

AIM: The Thrombolysis in Myocardial Infarction (TIMI) risk score (range 0-7), used for emergency department (ED) risk stratification of patients with suspected acute coronary syndrome (ACS), underestimates risk associated with ECG changes or cardiac troponin elevation. A modified TIMI score (mTIMI, range 0-10), which gives increased weighting to these variables, has been proposed. We aimed to evaluate the performance of the mTIMI score in ED patients with suspected ACS. METHODS: A multicentre prospective observational study enrolled patients undergoing assessment for possible ACS. TIMI and mTIMI scores were calculated. The study outcome was a composite of all-cause death, myocardial infarction or coronary revascularisation within 30 days. RESULTS: Of the 1666 patients, 219 (13%) reached the study outcome. Area under the receiver operating characteristic curve for the composite outcome was 0.80 (0.76 to 0.83) for the mTIMI score compared with 0.71 (0.67 to 0.74) for the standard TIMI score, p<0.001, but there was no significant difference for death or revascularisation outcomes. Sensitivity and specificity for the composite outcome were 0.96 (0.92 to 0.98) and 0.23 (0.20 to 0.26), respectively, at score 0 for TIMI and mTIMI. At score <2, sensitivity and specificity were 0.82 (0.77 to 0.87) and 0.53 (0.51 to 0.56) for mTIMI, and 0.74 (0.68 to 0.79) and 0.54 (0.51 to 0.56) for standard TIMI, respectively. CONCLUSIONS: mTIMI score performs better than standard TIMI score for ED risk stratification of chest pain, but neither is sufficiently sensitive at scores >0 to allow safe and early discharge without further investigation or follow-up. Observed differences in performance may be due to incorporation bias.