The natural history of the systemic inflammatory response syndrome (SIRS). A prospective study

Prospective evaluation of the quickSOFA score as a screening for sepsis in the emergency department

In 2016, the new bedside tool quick Sequential (Sepsis-related) Organ Failure Assessment (qSOFA) was presented to identify patients at high risk of developing sepsis or adverse outcome. The aim of this study was to investigate the diagnostic performance of the qSOFA scoring system as a screening in patients presenting at an emergency department (ED) of any cause. Therefore, we compared qSOFA with the systemic inflammatory response syndrome (SIRS) criteria and two modifications of qSOFA score. This is a prospective single-center study including patients presenting to the ED of any non-traumatic cause. Primary outcome was development of sepsis within 48 h, secondary outcomes were 30-day mortality and ICU stay for > 3 days. Data were collected within one hour after arrival to indicate an impression of initial medical contact. Among 1,668 patients, 105 sepsis cases were identified. 8.4% presented with qSOFA ≥ 2, 27.2% with SIRS ≥ 2 within one hour. Sensitivity of qSOFA in predicting sepsis was lower compared to the SIRS criteria. qSOFA showed better prognostic accuracy for 30-day mortality compared to SIRS (p < 0.05), but not for prolonged ICU stay (p = 0.56). Modification of qSOFA in replacing GCS by other scoring systems recording altered mental status did not improve its sensitivity. The qSOFA score has poor sensitivity to identify patients at risk of developing sepsis and can therefore not be considered as an adequate screening for sepsis in patients presenting to the ED. Furthermore, a positive qSOFA at arrival at the ED showed no sufficient reliability in detecting patients with adverse clinical course.

The development an artificial intelligence algorithm for early sepsis diagnosis in the intensive care unit

BACKGROUND

Severe sepsis and septic shock are still the leading causes of death in Intensive Care Units (ICUs), and timely diagnosis is crucial for treatment outcomes. The progression of electronic medical records (EMR) offers the possibility of storing a large quantity of clinical data that can facilitate the development of artificial intelligence (AI) in medicine. However, several difficulties, such as poor structure and heterogenicity of the raw EMR data, are encountered when introducing AI with ICU data. Labor-intensive work, including manual data entry, personal medical records sorting, and laboratory results interpretation may hinder the progress of AI. In this article, we introduce the developing of an AI algorithm designed for sepsis diagnosis using pre-selected features; and compare the performance of the AI algorithm with SOFA score based diagnostic method.

MATERIALS AND METHODS

This is a prospective open-label cohort study. A specialized EMR, named TED_ICU, was implemented for continuous data recording. One hundred six clinical features relevant to sepsis diagnosis were selected prospectively. A labeling work to allocate SEPSIS or NON_SEPSIS status for each ICU patient was performed by the in-charge intensivist according to SEPSIS-3 criteria, along with the automatic recording of selected features every day by TED_ICU. Afterward, we use de-identified data to develop the AI algorithm. Several machine learning methods were evaluated using 5-fold cross-validation, and XGBoost, a decision-tree based algorithm was adopted for our AI algorithm development due to best performance.

RESULTS

The study was conducted between August 2018 and December 2018 for the first stage of analysis. We collected 1588 instances, including 444 SEPSIS and 1144 NON-SEPSIS, from 434 patients. The 434 patients included 259 (59.6%) male patients and 175 female patients. The mean age was 67.6-year-old, and the mean APACHE II score was 13.8. The SEPSIS cohort had a higher SOFA score and increased use of organ support treatment. The AI algorithm was developed with a shuffle method using 80% of the instances for training and 20% for testing. The established AI algorithm achieved the following: accuracy = 82% ± 1%; sensitivity = 65% ± 5%; specificity = 88% ± 2%; precision = 67% ± 3%; and F1 = 0.66 ± 0.02. The area under the receiver operating characteristic curve (AUROC) was approximately 0.89. The SOFA score was used on the same 1588 instances for sepsis diagnosis, and the result was inferior to our AI algorithm (AUROC = 0.596).

CONCLUSION

Using real-time data, collected by EMR, from the ICU daily practice, our AI algorithm established with pre-selected features and XGBoost can provide a timely diagnosis of sepsis with an accuracy greater than 80%. AI algorithm also outperforms the SOFA score in sepsis diagnosis and exhibits practicality as clinicians can deploy appropriate treatment earlier. The early and precise response of this AI algorithm will result in cost reduction, outcome improvement, and benefit for healthcare systems, medical staff, and patients as well.

Antibacterial Fusion Protein BPI21/LL-37 Modification Enhances the Therapeutic Efficacy of hUC-MSCs in Sepsis

Sepsis, which is characterized by multiple organ dysfunctions as a result of an unbalanced host-inflammatory response to pathogens, is potentially a life-threatening condition and a major cause of death in the intensive care units (ICUs). However, effective treatment or intervention to prevent sepsis-associated lethality is still lacking. Human umbilical cord mesenchymal stem cell (hUC-MSC) transplantation has been shown to have potent immunomodulatory properties and improve tissue repair yet lacks direct antibacterial and endotoxin clearance activities. In this study, we engineered hUC-MSCs to express a broad-spectrum antibacterial fusion peptide containing BPI21 and LL-37 (named BPI21/LL-37) and confirmed that the BPI21/LL-37 modification did not affect the stemness and immunoregulatory capacities of hUC-MSCs but remarkably, enhanced its antibacterial and toxin-neutralizing activities in vitro. Furthermore, we showed that administration of BPI21/LL-37-engineered hUC-MSCs significantly reduces serum levels of tumor necrosis factor α (TNF-α), interleukin 1β (IL-1β), and IL-6, whereas increases that of IL-10 in cecal ligation and puncture (CLP)-induced sepsis mouse model. Administration of BPI21/LL-37-engineered hUC-MSCs significantly reduced systemic endotoxin (lipopolysaccharide [LPS]) levels and organ bacterial load, ameliorated damage to multiple organs, and improved survival. Taken together, our study demonstrates that BPI21/LL-37-engineered hUC-MSCs might offer a novel therapeutic strategy to prevent or treat sepsis via enhanced antimicrobial and anti-inflammatory properties to preserve organ functions better.

Monocyte distribution width enhances early sepsis detection in the emergency department beyond SIRS and qSOFA

Background

The initial presentation of sepsis in the emergency department (ED) is difficult to distinguish from other acute illnesses based upon similar clinical presentations. A new blood parameter, a measurement of increased monocyte volume distribution width (MDW), may be used in combination with other clinical parameters to improve early sepsis detection. We sought to determine if MDW, when combined with other available clinical parameters at the time of ED presentation, improves the early detection of sepsis.

Methods

A retrospective analysis of prospectively collected clinical data available during the initial ED encounter of 2158 adult patients who were enrolled from emergency departments of three major academic centers, of which 385 fulfilled Sepsis-2 criteria, and 243 fulfilled Sepsis-3 criteria within 12 h of admission. Sepsis probabilities were determined based on MDW values, alone or in combination with components of systemic inflammatory response syndrome (SIRS) or quick sepsis-related organ failure assessment (qSOFA) score obtained during the initial patient presentation (i.e., within 2 h of ED admission).

Results

Abnormal MDW (> 20.0) consistently increased sepsis probability, and normal MDW consistently reduced sepsis probability when used in combination with SIRS criteria (tachycardia, tachypnea, abnormal white blood count, or body temperature) or qSOFA criteria (tachypnea, altered mental status, but not hypotension). Overall, and regardless of other SIRS or qSOFA variables, MDW > 20.0 (vs. MDW ≤ 20.0) at the time of the initial ED encounter was associated with an approximately 6-fold increase in the odds of Sepsis-2, and an approximately 4-fold increase in the odds of Sepsis-3.

Conclusions

MDW improves the early detection of sepsis during the initial ED encounter and is complementary to SIRS and qSOFA parameters that are currently used for this purpose. This study supports the incorporation of MDW with other readily available clinical parameters during the initial ED encounter for the early detection of sepsis.

Trial registration

ClinicalTrials.gov, NCT03145428. First posted May 9, 2017. The first subjects were enrolled June 19, 2017, and the study completion date was January 26, 2018.

Culture-Negative and Culture-Positive Sepsis: A Comparison of Characteristics and Outcomes

BACKGROUND

The primary objective of this study was to compare the characteristics of culture-positive and culture-negative status in septic patients. We also determined whether culture status is associated with mortality and whether unique variables are associated with mortality in culture-positive and culture-negative patients separately.

METHODS

Utilizing patient records from intensive care units, emergency department, and general care wards in a large academic medical center, we identified adult patients with suspected infection and ≥2 systemic inflammatory response syndrome criteria between January 1, 2007, and May 31, 2014. We compared the characteristics between culture-positive and culture-negative patients and used binary logistic regression to identify variables independently associated with culture status and mortality. We also did sensitivity analyses using patients with Sequential Organ Failure Assessment and quick Sequential Organ Failure Assessment criteria for sepsis.

RESULTS

The study population included 9288 culture-negative patients (89%) and 1105 culture-positive patients (11%). Culture-negative patients received more antibiotics during the 48 hours preceding diagnosis but otherwise demonstrated similar characteristics as culture-positive patients. After adjusting for illness severity, a positive culture was not independently associated with mortality (odds ratio = 1.01 [95% CI, 0.81-1.26]; P = .945). The models predicting mortality separately in culture-negative and culture-positive patients demonstrated very good and excellent discrimination (C-statistic ± SD, 0.87 ± 0.01 and 0.92 ± 0.01), respectively. In the sensitivity analyses using patients with sepsis by Sequential Organ Failure Assessment and quick Sequential Organ Failure Assessment criteria, after adjustments for illness severity, positive cultures were still not associated with mortality (odds ratio = 1.13 [95% CI, 0.86-1.43]; P = .303; and odds ratio = 1.05 [95% CI, 0.83-1.33]; P = .665), respectively. In all models, physiological derangements were associated with mortality.

CONCLUSIONS

While culture status is important for tailoring antibiotics, culture-negative and culture-positive patients with sepsis demonstrate similar characteristics and, after adjusting for severity of illness, similar mortality. The most important factor associated with negative cultures is receipt of antibiotics during the preceding 48 hours. The risk of death in patients suspected of having an infection is most associated with severity of illness. This is aligned with the Sepsis-3 definition using Sequential Organ Failure Assessment score to better identify those suspected of infection at highest risk of a poor outcome.

Mitochondria-Targeted Drugs

Background:

Targeting of drugs to the subcellular compartments represents one of the modern trends in molecular pharmacology. The approach for targeting mitochondria was developed nearly 50 years ago, but only in the last decade has it started to become widely used for delivering drugs. A number of pathologies are associated with mitochondrial dysfunction, including cardiovascular, neurological, inflammatory and metabolic conditions.

Objective:

This mini-review aims to highlight the role of mitochondria in pathophysiological conditions and diseases, to classify and summarize our knowledge about targeting mitochondria and to review the most important preclinical and clinical data relating to the antioxidant lipophilic cations MitoQ and SkQ1.

Methods:

This is a review of available information in the PubMed and Clinical Trials databases (US National Library of Medicine) with no limiting period.

Results and Conclusion:

Mitochondria play an important role in the pathogenesis of many diseases and possibly in aging. Both MitoQ and SkQ1 have shown many beneficial features in animal models and in a few completed clinical trials. More clinical trials and research efforts are needed to understand the signaling pathways influenced by these compounds. The antioxidant lipophilic cations have great potential for the treatment of a wide range of pathologies.

<p>Antibiotic Therapy for Children with Diarrhea in a Low-Resource Setting: A Syndromic Approach</p>

Objective

Design

Setting

Participants

Interventions

Main Outcome Measures

Results

Conclusion

Characteristics and outcomes of bacteremia among ICU-admitted patients with severe sepsis

The clinical implications of bacteremia among septic patients remain unclear, although a vast amount of data have been accumulated on sepsis. We aimed to compare the clinical characteristics and outcomes of severe sepsis patients with and without bacteremia. This secondary analysis of a multicenter, prospective cohort study included 59 intensive care units (ICUs) in Japan between January 2016 and March 2017. The study cohort comprised 1,184 adults (aged ≥ 16 years) who were admitted to an ICU with severe sepsis and diagnosed according to the Sepsis-2 criteria. Of 1,167 patients included in the analysis, 636 (54.5%) had bacteremia. Those with bacteremia had significantly higher rates of septic shock (66.4% vs. 58.9%, p = 0.01) and higher sepsis severity scores, including the Acute Physiology and Chronic Health Evaluation (APACHE) II and the Sequential Organ Failure Assessment (SOFA). No significant difference in in-hospital mortality was seen between patients with and without bacteremia (25.6% vs. 21.0%, p = 0.08). In conclusion, half of severe sepsis patients in ICUs have bacteremia. Although patients with bacteremia had more severe state, between-group differences in patient-centered outcomes, such as in-hospital mortality, have not been fully elucidated.

Evaluation of serum C-reactive protein and high mobility group box 1 concentrations in 22 dogs with acute pancreatitis: a pilot study

Background: High mobility group box 1 (HMGB1) is an important mediator of systemic inflammatory response syndrome (SIRS) in humans with severe acute pancreatitis (AP), but there is little information regarding its role in dogs. Aim: To compare the serum concentrations of C-reactive protein (CRP) and HMGB1 in healthy dogs and those with AP with or without SIRS. Methods: The study included 22 dogs with AP and 20 healthy dogs. CRP and HMGB1 were assessed by ELISA. Statistical analyses were conducted by non-parametric tests. Results: Median (interquartile range) serum CRP and HMGB1 concentrations were significantly (P < 0.05) higher in dogs with AP [60.56 (14.50-140.10) µg/mL and 0.35 (0.03-1.12) ng/mL, respectively] than in healthy dogs [2.23 (1.75-5.14) µg/mL and 0.02 (0.01-0.05) ng/mL, respectively]. After the recommended treatments for AP, serum CRP concentration in AP dogs significantly decreased, but that of HMGB1 in AP dogs significantly increased. There was also a significant difference in median serum HMGB1 concentration between AP dogs with and without SIRS. The use of serum HMGB1 concentration of 0.35 ng/mL to distinguish AP dogs with and without SIRS was associated with a sensitivity of 87.5% and a specificity of 71.5%. A positive correlation was identified between HMGB1 and clinical severity of AP. All AP dogs had a positive outcome during hospitalization [6.0 (1.5-6.0) days]. Conclusion: Results indicate that HMGB1 might be a useful biomarker for the progression of AP and may play a role in progression of AP into SIRS in dogs.

Medicina de precisión en sepsis: utilidad de los biomarcadores en pacientes biomarcadores en pacientes críticamente enfermos

Durante años la evolución del cuidado intensivo ha intentado ofrecer una atención basada en protocolos y paquetes de manejo agrupados por patologías y cuadro sindromáticos. Aunque se logró disminuir la mortalidad en diferentes patologías (sepsis y síndromes coronario agudo y de distrés respiratorio agudo), no se han resuelto por completo los problemas clínicos, en especial el diagnóstico y el manejo. Una nueva opción ha surgido en el horizonte denominada “medicina de precisión”, entendida como estrategia de prevención y tratamiento que tiene en cuenta la variabilidad individual. La sepsis es un síndrome con múltiples aristas en cuanto al fenotipo y genotipo, cuyo diagnóstico temprano es relevante para los desenlaces clínicos. Hasta el momento el enfoque principal ha sido la identificación de un germen etiológico para diferenciarla del síndrome de respuesta inflamatoria sistémica (SIRS). En los últimos años el paradigma en enfermedades infecciosas ha cambiado debido a estudios que demuestran como la respuesta inmunitaria del paciente séptico tiene un papel clave en el desarrollo de la enfermedad, con implicaciones en el diagnóstico, pronóstico y tratamiento, que podrían ayudar a cambiar el abordaje en los próximos años gracias a una estrategia basada en medicina de precisión. Hoy los aislamientos microbiológicos y los cultivos siguen siendo el estándar de referencia con varias desventajas como el tiempo para obtener resultados, sobre todo en infecciones por gérmenes resistentes u hongos, que pueden retrasar el inicio de la terapia antimicrobiana. Como alternativa se ha planteado el uso de biomarcadores en sepsis que siendo productos de la respuesta inflamatoria del individuo ante la infección, son útiles para el diagnóstico y pronóstico primordialmente en los críticamente enfermos. Decidimos realizar esta revisión narrativa acerca de la utilidad de los biomarcadores en pacientes con sepsis críticamente enfermos, para enfocarlos en un modelo de medicina personalizada.

Combination of vitamin C, thiamine and hydrocortisone added to standard treatment in the management of sepsis: results from an open label randomised controlled clinical trial and a review of the literature

Background: Combination of vitamin C, hydrocortisone and thiamine have recently been used in sepsis but data of efficacy are conflicting and no data are available from developing countries. We sought to study the effect of addition of this combination to standard care in patients with sepsis/septic shock in a north Indian setting.Methods: In a prospective, open label, randomised fashion, 100 patients with sepsis/septic shock were recruited to receive either standard therapy alone (control group, n = 50) or a combination of vitamin C, thiamine and hydrocortisone (treatment group, n = 50) in addition. The patients were followed for various clinical and laboratory parameters, in-hospital and 30-day mortality, duration of vasopressor use, lactate clearance, duration of hospital stay, and change in serum lactate and the SOFA score over the first 4 days.Results: The 2 groups were matched for basic characteristics. The in-hospital mortality (28% in controls and 24% in treatment group, p = .82) and 30-day mortality (42% in controls and 40% in treatment group, p = 1.00) was not significantly different in the 2 groups. However, there was a significant difference in duration of vasopressor use (96.13 ± 40.50 h in control group v/s 75.72 ± 30.29 h in treatment group, p value = .010) and lactate clearance (control group: 41.81% v/s treatment group: 56.83%, p value =.031) between 2 groups.Conclusions: Addition of vitamin C, hydrocortisone, and thiamine into standard care of sepsis does not improve in-hospital or 30 day mortality. However lower vasopressor use and faster lactate clearance is observed with treatment.

Levels of matrix metalloproteinase-9 and tissue inhibitor of metalloproteinase-1 are related to cardiopulmonary injury in fetal inflammatory response syndrome

OBJECTIVES

To evaluate the diagnostic value of matrix metalloproteinase-9 (MMP-9), tissue inhibitor of metalloproteinase-1 (TIMP-1), and the MMP-9/TIMP-1 ratio in fetal inflammatory response syndrome (FIRS), and determine a possible association with the incidence of bronchopulmonary dysplasia (BPD) and myocardial injury.

METHODS

Overall, 61 cases of preterm infants with FIRS were divided into the FIRS group 1 (≤32 weeks) and FIRS group 2 (32 to 37 weeks). Similarly, 57 cases of normal preterm infants were divided into Control group 1 and Control group 2. Levels of interleukin-6 (IL-6), MMP-9, and TIMP-1 were detected by enzyme-linked immunosorbent assay. Spearman's linear correlation was used to analyze the relationship between dependent variables. Pathological changes were examined by hematoxylin and eosin (HE) staining and in amniotic fluid smears.

RESULTS

Levels of IL-6, MMP-9, and TIMP-1, and the MMP-9/TIMP-1 ratio were significantly higher in the FIRS group than in the Control groups. IL-6 was positively correlated with MMP-9, TIMP-1, and the MMP-9/TIMP-1 ratio. Areas under the curve (AUC) of MMP-9, TIMP-1, and the MMP-9/TIMP-1 ratio were 0.92, 0.90, and 0.95, respectively. HE staining and amniotic fluid smears showed the aggregation of inflammatory cells. MMP-9, TIMP-1, and the MMP-9/TIMP-1 ratio were closely related to the incidence of BPD (≤32 weeks) and myocardial injury (<37 weeks) in preterm infants.

CONCLUSION

MMP-9, TIMP-1, and the MMP-9/TIMP-1 ratio revealed a certain diagnostic value for FIRS; combined with gestational age, these parameters were effective for predicting cardiopulmonary injury.

B lymphocytopenia and Bregs in a not-to-die murine sepsis model

Sepsis is a leading cause of mortality in intensive care units due to multi-organ failure caused by dysregulated immune reactions. In this study, kinetic changes in the immune system were analyzed for 72 h in cecal ligation and puncture (CLP)-induced septic mice while preventing animal death by keeping body temperature. Increase of myeloid cells and decrease of B cells in circulation at 6 h after CLP were markedly observed. At the same time point, interleukin (IL)-10 expressing CD5⁺ regulatory B cells (Bregs) appeared. IL-10 and programmed death-ligand 1 (PD-L1) mRNA as well as IL-1β, IL-6 and interferon γ (IFNγ) mRNA was increased in the spleen at 6 h. A gradual decrease in Bcl-2 and abrupt increase of Bim expression in the spleen at the late phase were also found. These results showed that B lymphocytopenia with the appearance of Bregs is the earliest event, likely leading to immunoparalysis in sepsis.

On-site blood culture incubation shortens the time to knowledge of positivity and microbiological results in septic patients

Introduction

To determine whether on-site incubation of blood cultures at the intensive care unit (ICU) improves not only the time to incubation but also time to positivity, time to knowledge of positivity and time to results (identification and antibiotic susceptibility testing).

Methods

This observational single-centre study in ICU patients with severe sepsis and septic shock investigated the impact of blood culture incubation immediately on-site at the ICU (ICU group) by comparison with traditional processing in a remote laboratory (LAB group) on different time intervals of blood culture diagnostics from obtaining blood to clinician notification of final result. The effect of on-site incubation was evaluated in Kaplan-Meier estimates for the time to positivity, time to knowledge of positivity and time to microbiological results and a linear mixed model was built.

Results

A total of 3,549 blood culture sets from 657 ICU patients were analysed: 2,381 in the LAB group and 1,168 in the ICU group. Overall, 660 (18.6%) blood culture sets were positive and 2,889 (81.4%) sets remained negative. On-site incubation was associated with reduced time to knowledge of positivity (46.9 h [CI 43.4–50.8 h] vs. 28.0 h [CI 23.6–32.2 h], p < 0.001) and reduced time to result (61.4 h [CI 58.4–64.8 h] vs. 42.1 h [CI 39.1–47.5 h], p < 0.001). In blood cultures processed instantaneously at the ICU compared to incubation in the remote laboratory within 4 h, the time to microbiological result was significantly reduced by 8.5 h (p < 0.001). Pre-existing anti-infective therapy had no significant impact on diagnostic time intervals.

Conclusions

Instantaneous incubation of blood cultures in the ICU compared to incubation in a remote laboratory significantly improves time to knowledge to positivity and time to result. These effects are even more pronounced during off-hours of the microbiological laboratory. The results underline the importance of 24/7 diagnostics to provide round-the-clock processing of blood culture samples in patients with sepsis and septic shock and an immediate to communication of the results to the clinicians.

Hydrogel based protein biochip for parallel detection of biomarkers for diagnosis of a Systemic Inflammatory Response Syndrome (SIRS) in human serum

The Systemic Inflammatory Response Syndrome (SIRS), a sepsis related inflammatory state, is a self-defense mechanism against specific and nonspecific stimuli. The six most extensively studied inflammatory biomarkers for the clinical diagnosis of SIRS are interleukin 4 (hIL-4), interleukin 6 (hIL-6), interleukin 10 (hIL-10), tumor necrosis factor alpha (hTNF-α), interferon gamma (hIFN-γ) and procalcitonin (hPCT). These biomarkers are naturally present (but usually only at low concentration) in SIRS infected patients [1, 2] and thus the development of a highly sensitive detection method is of major clinical interest. However, the existing analytical techniques are lacking in required analytical sensitivity and parallel determination of these biomarkers. We developed a fast, easy and cost-efficient protein microarray biochip where the capture molecules are attached on hydrogel spots, enabling SIRS diagnosis by parallel detection of these six clinically relevant biomarkers with a sample volume of 25 μl. With our hydrogel based protein microarray biochip we achieved a limit of detection for hIL-4 of 75.2 pg/ml, for hIL-6 of 45.1 pg/ml, for hIL-10 of 71.5 pg/ml, for hTNF-α of 56.7 pg/ml, for IFN-γ of 46.4 pg/ml and for hPCT of 1.1 ng/ml in spiked human serum demonstrating sufficient sensitivity for clinical usage. Additionally, we demonstrated successful detection of two relevant SIRS biomarkers in clinical patient samples with a turnaround time of the complete analysis from sample-to-answer in less than 200 minutes.

Renal Tubular Glucagon-Like Peptide-1 Receptor Expression Is Increased in Early Sepsis but Reduced in Chronic Kidney Disease and Sepsis-Induced Kidney Injury

Acute kidney injury (AKI) is common in patients with sepsis and causes renal ischemia. Glucagon-like peptide-1 (GLP-1) protects the vascular system and the kidney, and GLP-1 receptor (GLP-1R) is expressed in the kidney. Renal GLP-1R activity is decreased in chronic kidney disease (CKD), but is increased by the inflammatory response; however, the effect of AKI on GLP-1R expression is unknown. We investigated the role of GLP-1 by assessing GLP-1R expression in the renal cortex in animals with AKI-related sepsis, CKD, and CKD-with-sepsis. We generated a model of CKD by 5/6 nephrectomy, and sepsis induced by cecal perforation, in male Sprague-Dawley rats. We compared renal GLP-1R expression at 3, 6, 12, 24, and 72 h after cecal perforation, and in CKD and CKD-with-sepsis. We performed blood and urine tests, western blotting (WB), and immunohistochemistry (IHC) to assay GLP-1R expression in renal tubules. The CKD-with-sepsis group showed the lowest kidney function, urine volume, and serum glucose and albumin levels. GLP-1R expression in renal tubules was decreased at 3 h, increased at 24 h, and decreased at 72 h after sepsis induction. GLP-1R expression was decreased at 8 weeks after CKD and was lowest in the CKD-with-sepsis group. The WB results were verified against those obtained by IHC. GLP-1R expression in renal tubules is increased in early sepsis, which may explain the protective effect of endogenous GLP-1 against sepsis-related inflammation.

Sepsis 2019: What Surgeons Need to Know

The definition of sepsis continues to be as dynamic as the management strategies used to treat this. Sepsis-3 has replaced the earlier systemic inflammatory response syndrome (SIRS)-based diagnoses with the rapid Sequential Organ Failure Assessment (SOFA) score assisting in predicting overall prognosis with regards to mortality. Surgeons have an important role in ensuring adequate source control while recognizing the threat of carbapenem-resistance in gram-negative organisms. Rapid diagnostic tests are being used increasingly for the early identification of multi-drug-resistant organisms (MDROs), with a key emphasis on the multidisciplinary alert of results. Novel, higher generation antibiotic agents have been developed for resistance in ESKCAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) organisms while surgeons have an important role in the prevention of spread. The Study to Optimize Peritoneal Infection Therapy (STOP-IT) trial has challenged the previous paradigm of length of antibiotic treatment whereas biomarkers such as procalcitonin are playing a prominent role in individualizing therapy. Several novel therapies for refractory septic shock, while still investigational, are gaining prominence rapidly (such as vitamin C) whereas others await further clinical trials. Management strategies presented as care bundles continue to be updated by the Surviving Sepsis Campaign, yet still remain controversial in its global adoption. We have broadened our temporal and epidemiologic perspective of sepsis by understanding it both as an acute, time-sensitive, life-threatening illness to a chronic condition that increases the risk of mortality up to five years post-discharge. Artificial intelligence, machine learning, and bedside scoring systems can assist the clinician in predicting post-operative sepsis. The public health role of the surgeon is key. This includes collaboration and multi-disciplinary antibiotic stewardship at a hospital level. It also requires controlling pharmaceutical sales and the unregulated dispensing of antibiotic agents globally through policy initiatives to control emerging resistance through prevention.

Blood Culture Results Before and After Antimicrobial Administration in Patients With Severe Manifestations of Sepsis: A Diagnostic Study

BACKGROUND

Administering antimicrobial agents before obtaining blood cultures could potentially decrease time to treatment and improve outcomes, but it is unclear how this strategy affects diagnostic sensitivity.

OBJECTIVE

To determine the sensitivity of blood cultures obtained shortly after initiation of antimicrobial therapy in patients with severe manifestations of sepsis.

DESIGN

Patient-level, single-group, diagnostic study. (ClinicalTrials.gov: NCT01867905).

SETTING

7 emergency departments in North America.

PARTICIPANTS

Adults with severe manifestations of sepsis, including systolic blood pressure less than 90 mm Hg or a serum lactate level of 4 mmol/L or more.

INTERVENTION

Blood cultures were obtained before and within 120 minutes after initiation of antimicrobial treatment.

MEASUREMENTS

Sensitivity of blood cultures obtained after initiation of antimicrobial therapy.

RESULTS

Of 3164 participants screened, 325 were included in the study (mean age, 65.6 years; 62.8% men) and had repeated blood cultures drawn after initiation of antimicrobial therapy (median time, 70 minutes [interquartile range, 50 to 110 minutes]). Preantimicrobial blood cultures were positive for 1 or more microbial pathogens in 102 of 325 (31.4%) patients. Postantimicrobial blood cultures were positive for 1 or more microbial pathogens in 63 of 325 (19.4%) patients. The absolute difference in the proportion of positive blood cultures between pre- and postantimicrobial testing was 12.0% (95% CI, 5.4% to 18.6%; P < 0.001). Sensitivity of postantimicrobial culture was 52.9% (CI, 42.8% to 62.9%). When the results of other microbiological cultures were included, microbial pathogens were found in 69 of 102 (67.6% [CI, 57.7% to 76.6%]) patients.

LIMITATION

Only a proportion of screened patients were recruited.

CONCLUSION

Among patients with severe manifestations of sepsis, initiation of empirical antimicrobial therapy significantly reduces the sensitivity of blood cultures drawn shortly after treatment initiation.

PRIMARY FUNDING SOURCE

Vancouver Coastal Health, St. Paul's Hospital Foundation Emergency Department Support Fund, the Fonds de recherche Santé-Québec, and the Maricopa Medical Foundation.

Impact of Bacterial Translocation on Sarcopenia in Patients with Decompensated Cirrhosis

Advanced liver disease is associated with a persistent inflammatory state, derived from abnormal bacterial translocation from the gut, which may contribute to the development of sarcopenia in cirrhosis. We aim to document the association of chronic inflammation and bacterial translocation with the presence of sarcopenia in cirrhosis. We prospectively followed cirrhotic patients aged 18-70 years with medically refractory ascites at a single tertiary care center in Toronto, Canada. The baseline data included patient demographic variables, the presence of bacterial DNA in serum/ascitic fluid, systemic inflammatory response syndrome (SIRS) status, and nutritional assessment. Thirty-one patients were enrolled, 18 (58.1%) were sarcopenic, 9 (29%) had bacterial DNA in serum and ascites fluid. The mean MELD score was 11.5 ± 4.0 (6-23). Sarcopenic and non-sarcopenic patients did not differ significantly in their baseline MELD scores, caloric intake, resting energy expenditure, the incidence of bacterial translocation, or SIRS. While sarcopenia was not linked to increased hospital admissions or death, it was strongly associated with increased episodes of acute kidney injury (3 vs. 0, p = 0.05). This pilot study did not demonstrate an association between sarcopenia and SIRS or bacterial translocation. These results should be confirmed in future larger studies, encompassing a greater number of chronic inflammation events and quantifying levels of bacterial DNA.

Involvement of Aromatic Metabolites in the Pathogenesis of Septic Shock

INTRODUCTION

We hypothesized that aromatic microbial metabolites (AMM), such as phenyllactic (PhLA), p-hydroxyphenylacetic (p-HPhAA), and p-hydroxyphenyllactic (p-HPhLA) acids, contribute to the pathogenesis of septic shock.

METHODS

Clinical and laboratory data of patients with community-acquired pneumonia were obtained on intensive care unit admission and the next day. Patients were divided into two groups based on septic shock presence or absence. The levels of AMM (PhLA, p-HPhAA, p-HPhLA, and their sum, ∑3AMM), catecholamine metabolites (3,4-dihydroxymandelic [DHMA], 3,4-dihydroxyphenylacetic [DOPAC], and homovanillic [HVA] acids), lactate, N-terminal pro-brain natriuretic peptide (NT-proBNP), inducible nitric oxide synthase (iNOS), and procalcitonin (PCT) were compared. Correlations between AMM and clinical and laboratory data were calculated.

RESULTS

There were 20 patients in the septic shock group and 21 in the nonseptic shock group. On admission, the septic shock patients demonstrated significantly higher levels of PhLA (2.3 vs. 0.8 μmol/L), p-HPhAA (4.6 vs. 1.4 μmol/L), p-HPhLA (7.4 vs. 2.6 μmol/L), HVA, lactate, and significantly lower levels of iNOS. The next day, the two groups also showed significant differences in the levels of PCT and NT-proBNP. The correlation between ∑3AMM and presence of shock, levels of lactate, HVA, and NT-proBNP on admission was 0.44, 0.67, 0.57, and 0.38, respectively, and the correlation on the next day was 0.59, 0.73, 0.76, and 0.6, respectively (P < 0.01). These findings can be explained by the ability of AMM to reduce tyrosine hydroxylase activity, thus limiting the synthesis of catecholamines.

CONCLUSIONS

AMM are involved in the pathogenesis of septic shock.

Long-Term Survival of Young Patients Surviving ICU Admission With Severe Sepsis

OBJECTIVES

Sepsis remains a disease with a high mortality rate. The study goal was to assess long-term survival of severe sepsis in young patients.

DESIGN

Retrospective cohort study.

SETTING

Patients admitted with sepsis to ICUs in seven tertiary hospitals between 2003 and 2011.

PATIENTS

A total of 409 patients less than 45 years who survived to hospital discharge were age and sex matched with 818 patients with infectious disease without sepsis selected from internal medicine or surgical department admissions.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The median age in sepsis patients and the comparison group was 31 and 32 years, respectively. The proportions of patients surviving after hospital discharge were significantly lower in the sepsis group compared with the control group; among survivors, 6-month, 1-year, and 3-year mortality rates were 0.7% versus 0%, 4.5% versus 0.7%, 7.9% versus 1.2%, and 10.8% versus 1.8%, respectively (p < 0.001 for all). In a multivariate Cox proportional hazards regression model, sepsis was associated with an increased risk of mortality (hazard ratio, 3.79; 95% CI, 2.27-6.32), while controlling for age, Charlson Comorbidity Index, history of stroke, and congestive heart failure. Past the 24-month landmark, sepsis was not found to be an independent risk for mortality (hazard ratio, 1.79; 95% CI, 0.67-4.79). Based on cause of death analysis, chronic underlying comorbidities might explain the excess mortality in patients with sepsis.

CONCLUSIONS

Young patients experiencing an episode of severe sepsis continue to be at higher risk of long-term mortality. The highest mortality rates were observed during the first 24 months following discharge.

Predictive Validity of Sepsis-3 Definitions and Sepsis Outcomes in Critically Ill Patients: A Cohort Study in 49 ICUs in Argentina

OBJECTIVES

The new Sepsis-3 definitions have been scarcely assessed in low- and middle-income countries; besides, regional information of sepsis outcomes is sparse. Our objective was to evaluate Sepsis-3 definition performance in Argentina.

DESIGN

Cohort study of 3-month duration beginning on July 1, 2016.

SETTINGS

Forty-nine ICUs.

PATIENTS

Consecutive patients admitted to the ICU with suspected infection that triggered blood cultures and antibiotic administration.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Patients were classified as having infection, sepsis (infection + change in Sequential Organ Failure Assessment ≥ 2 points), and septic shock (vasopressors + lactate > 2 mmol/L). Patients on vasopressors and lactate less than or equal to 2 mmol/L (cardiovascular dysfunction) were analyzed separately, as those on vasopressors without serum lactate measurement. Systemic inflammatory response syndrome was also recorded. Main outcome was hospital mortality. Of 809 patients, 6% had infection, 29% sepsis, 20% cardiovascular dysfunction, 40% septic shock, and 3% received vasopressors with lactate unmeasured. Hospital mortality was 13%, 20%, 39%, 51%, and 41%, respectively (p = 0.000). Independent predictors of outcome were lactate, Sequential Organ Failure Assessment score, comorbidities, prior duration of symptoms (hr), mechanical ventilation requirement, and infection by highly resistant microorganisms. Area under the receiver operating characteristic curves for mortality for systemic inflammatory response syndrome and Sequential Organ Failure Assessment were 0.53 (0.48-0.55) and 0.74 (0.69-0.77), respectively (p = 0.000).

CONCLUSIONS

Increasing severity of Sepsis-3 categories adequately tracks mortality; cardiovascular dysfunction subgroup, not included in Sepsis-3, has distinct characteristics. Sequential Organ Failure Assessment score shows adequate prognosis accuracy-contrary to systemic inflammatory response syndrome. This study supports the predictive validity of Sepsis-3 definitions.

Extracellular Mitochondrial DNA and N-Formyl Peptides in Trauma and Critical Illness: A Systematic Review

OBJECTIVES

Extracellular mitochondrial DNA and N-formyl peptides released following tissue damage may contribute to systemic inflammation through stimulation of the innate immune system. In this review, we evaluate existing in vivo human data regarding a role for mitochondrial DNA and N-formyl peptides in producing systemic inflammation in trauma and critical illness, investigate the utility of these molecules in risk prediction and clinical decision support, and provide suggestions for standardization of future research.

DATA SOURCES

PubMed, Embase (1971-2017).

STUDY SELECTION

Studies measuring extracellular mitochondrial DNA and/or N-formyl peptides in acutely ill patients.

DATA EXTRACTION

Fifty-four studies were analyzed. Data extracted included article characteristics, methods, results, and performance in clinical prediction.

DATA SYNTHESIS

The most common patient types investigated were trauma (19 studies) and sepsis (eight). In studies comparing patient mitochondrial DNA or N-formyl peptide levels to healthy controls, 38 (90.5%) reported significantly elevated mitochondrial DNA levels in patients at first reported time point, as did the one study making this comparison for N-formyl peptides. Nine studies (81.8%) reported significantly elevated plasma/serum mitochondrial DNA levels in at least one time point in patients who developed inflammatory complications of their primary pathology compared with patients without inflammatory complications. For the ability of mitochondrial DNA to predict complications or outcomes, the area under the curve was 0.7 or greater in 84.6% of receiver operating characteristic curves, and 92.9% of odds, adjusted odds, risk, and hazard ratios were statistically significant.

CONCLUSIONS

Extracellular mitochondrial DNA levels are elevated early in patients' hospital courses in many acute illnesses and are higher in patients who develop inflammatory complications. Elevated mitochondrial DNA levels may be clinically useful in risk prediction and clinical decision support systems. Further research is needed to determine the role of extracellular N-formyl peptides in systemic inflammation and their possible clinical utility.

A novel use of attenuation value (Hounsfield unit) in non-contrast CT: diagnosis of pyonephrosis in obstructed systems

PURPOSE

To evaluate the predictive value of attenuation value (HU) in renal pelvis urine for detecting renal pelvis urine culture (RPUC) positivity in obstructed urinary systems.

METHODS

The study group consisted of patients who had nephrostomy insertion performed because of obstructed system and suspicion of pyonephrosis and percutaneous nephrolithotomy (PCNL) patients who had obstructed calculi. Group 1 consisted of RPUC positive 28 patients during nephrostomy insertion or needle access in PCNL and group 2 consisted of 23 patients with negative RPUC. RPUC results and non-contrast computed tomography measurements [Hounsfield unit (HU)] were compared between group 1 and group 2. A cut-off value was determined for HU. All patients were grouped according to whether they were above or below this value.

RESULTS

The median HU calculated from the renal pelvis was - 8.5 (range - 29/- 1) and 10 (range- 4/+ 17) (p < 0.001) in group 1 and group 2, respectively. The cut-off value of HU that predicted positive RPUC was 0. Sensitivity and specificity of HU when considering this cut-off value were 100% and 96%, respectively (p < 0.001). Whereas RPUC positivity was found in 96.6% (28/29) of patients with HU < 0, there were no patients with HU > 0 where RPUC positivity was detected (p < 0.001).

CONCLUSION

In this cohort, we found that HU of the urine in the renal pelvis can be used to predict RPUC positivity.

Culture-Negative Septic Shock Compared With Culture-Positive Septic Shock: A Retrospective Cohort Study

OBJECTIVES

To determine the clinical characteristics and outcomes of culture-negative septic shock in comparison with culture-positive septic shock.

DESIGN

Retrospective nested cohort study.

SETTING

ICUs of 28 academic and community hospitals in three countries between 1997 and 2010.

SUBJECTS

Patients with culture-negative septic shock and culture-positive septic shock derived from a trinational (n = 8,670) database of patients with septic shock.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Patients with culture-negative septic shock (n = 2,651; 30.6%) and culture-positive septic shock (n = 6,019; 69.4%) were identified. Culture-negative septic shock compared with culture-positive septic shock patients experienced similar ICU survival (58.3% vs 59.5%; p = 0.276) and overall hospital survival (47.3% vs 47.1%; p = 0.976). Severity of illness was similar between culture-negative septic shock and culture-positive septic shock groups ([mean and SD Acute Physiology and Chronic Health Evaluation II, 25.7 ± 8.3 vs 25.7 ± 8.1]; p = 0.723) as were serum lactate levels (3.0 [interquartile range, 1.7-6.1] vs 3.2 mmol/L [interquartile range, 1.8-5.9 mmol/L]; p = 0.366). As delays in the administration of appropriate antimicrobial therapy after the onset of hypotension increased, patients in both groups experienced congruent increases in overall hospital mortality: culture-negative septic shock (odds ratio, 1.56; 95% CI [1.47-1.66]; p < 0.0001) and culture-positive septic shock (odds ratio, 1.65; 95% CI [1.59-1.71]; p < 0.0001).

CONCLUSIONS

Patients with culture-negative septic shock behave similarly to those with culture-positive septic shock in nearly all respects; early appropriate antimicrobial therapy appears to improve mortality. Early recognition and eradication of infection is the most obvious effective strategy to improve hospital survival.

Global epidemiology and outcomes of acute kidney injury

Acute kidney injury (AKI) is a commonly encountered syndrome associated with various aetiologies and pathophysiological processes leading to decreased kidney function. In addition to retention of waste products, impaired electrolyte homeostasis and altered drug concentrations, AKI induces a generalized inflammatory response that affects distant organs. Full recovery of kidney function is uncommon, which leaves these patients at risk of long-term morbidity and death. Estimates of AKI prevalence range from <1% to 66%. These variations can be explained by not only population differences but also inconsistent use of standardized AKI classification criteria. The aetiology and incidence of AKI also differ between high-income and low-to-middle-income countries. High-income countries show a lower incidence of AKI than do low-to-middle-income countries, where contaminated water and endemic diseases such as malaria contribute to a high burden of AKI. Outcomes of AKI are similar to or more severe than those of patients in high-income countries. In all resource settings, suboptimal early recognition and care of patients with AKI impede their recovery and lead to high mortality, which highlights unmet needs for improved detection and diagnosis of AKI and for efforts to improve care for these patients.

MicroRNA-191-5p diminished sepsis-induced acute kidney injury through targeting oxidative stress responsive 1 in rat models

There is no effective treatment for septic acute kidney injury (AKI), which is considered a major public health concern in today’s world. Here, we studied the functions of miR-191-5p in septic AKI. MiR-191-5p mimic or mimic control was injected into rats from caudal vein before cecal ligation and puncture (CLP) surgery. Part of kidney tissues was stained by Hematoxylin and Eosin (H&E) for histological examination. The levels of serum cytokines were evaluated using enzyme-linked immunosorbent assay (ELISA). For cell transfection, renal cells were isolated from the kidneys of CLP rat model injected with mimic control and miR-191-5p mimic. With TargetScan prediction, serine/threonine-protein kinase OSR1 was identified as a target of miR-191-5p. Oxidative stress responsive 1 (OXSR1) overexpression vector was transfected into renal cells. Cell viability and apoptosis rate were determined by Cell Counting Kit-8 (CCK-8) and flow cytometry, respectively. We additionally measured the phosphorylation levels of p38 and p65. We found that the injection of miR-191-5p mimic could observably inhibit renal injury scores, and inhibit inflammatory cytokine productions and apoptotic protein levels in septic rats. After being transfected with OXSR1, the apoptosis rates and expressions of B-cell lymphoma-2 (Bcl-2), down-regulated Bax and Cleaved caspase-3 (C caspase-3) indicated overexpressed OXSR1 contributed to cell apoptosis. The up-regulated protein levels of p-p38 and p-p65 may suggest the involvement of p38 MAPK/NF-κB signaling pathway in the functions of OXSR1. Our results showed that the protective effects of miR-191-5p on kidney tissues of septic rats may rely on the repression of OXSR1.

Evaluation of qSOFA as a Predictor of Mortality Among ICU Patients With Positive Clinical Cultures-A Retrospective Cohort Study

OBJECTIVE

To compare the discriminative value of the quick-sequential organ failure assessment score (qSOFA) to SOFA in a critically ill population, in which a microbial pathogen was isolated within 48 hours of admission to intensive care.

DESIGN

Retrospective cohort study.

SETTING

Academic tertiary referral center from July 2008 to June 2017.

PATIENTS

Hospitalized patients admitted to intensive care unit.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The primary outcome was in-hospital mortality for all patients with confirmed positive microbiological cultures within 48 hours of admission to intensive care unit (ICU). Subgroup analysis was performed on patients with pathogenic bacteremia or positive cultures in cerebrospinal fluid. Of the 11 415 patients analyzed with positive microbiology specimens within 48 hours of admission, 2933 (25.7%) had a qSOFA ≥2. Of these, 16.6% reached the primary outcome of in-hospital mortality. Unsurprisingly, the discriminative value of qSOFA on admission was significantly worse than that of SOFA (0.73 vs 0.76; P = .0004), despite observing a significant association between qSOFA category and in-hospital mortality (P < .0001). In secondary analyses, similar observations were found using qSOFA within 6 and 24 hours of ICU admission. When analysis was focused on patients with pathogenic bacteremia or positive cerebrospinal fluid (CSF) cultures (n = 1646), there was no significant difference between the discriminative value of qSOFA and SOFA (0.75 vs 0.78; P = .17).

CONCLUSIONS

Quick-sequential organ failure assessment score at admission was not superior to SOFA in predicting in-hospital mortality in patients with positive clinical cultures within 48 hours of admission to ICU. Quick-sequential organ failure assessment score at admission to the ICU was associated with mortality and showed reasonable calibration and discrimination. When the analysis was focused on patients with pathogenic bacteremia or positive CSF cultures, qSOFA performed similarly to SOFA in discriminatory those who will die from sepsis.

Successful prospective quality improvement programme for the identification and management of patients at risk of sepsis in hospital

Objective

This audit aimed to improve the speed and completeness of delivery of treatment to urology patients at risk of sepsis in the hospital.

Patients and methods

Patients were prospectively included if they developed a new-onset systemic inflammatory response syndrome, were reviewed by a doctor who thought this was due to infection and prescribed antibiotics. We measured median time to antibiotic administration (TTABx) as the primary outcome. Factors associated with delays in management were identified, targeted quality improvement interventions implemented and then reaudited.

Results

There were 74 patients in the baseline cohort and 69 following interventions. Median TTABx fell from 3.6 (1.9–6.9) hours to 1.7 (1.0–3.8) p<0.001 hours after interventions. In the baseline cohort, factors significantly associated with a delay in TTABx were: an Early Warning Score less than the medical review trigger level; a temperature less than 38°C; having had surgery versus not. Interventions included: reduced medical review trigger thresholds, education sessions, communication aids, a department-specific sepsis protocol. There were significant improvements in the speed and completeness of sepsis management. Improvements were most marked in postoperative patients. Improvement longevity was achieved through continued work by permanent ward nurse practitioners.

Conclusion

A period of baseline prospective study, followed by tailored quality improvement initiatives, can significantly improve the speed and quality of sepsis management for inpatients on an acute hospital ward.

Targeting Endothelial Barrier Dysfunction Caused by Circulating Bacterial and Mitochondrial N-Formyl Peptides With Deformylase

Despite recent advances in our understanding of the mechanisms underlying systemic inflammatory response syndrome (SIRS) and sepsis, the current therapeutic approach to these critically ill patients is centered around supportive care including fluid resuscitation, vasopressors and source control. The incidence of SIRS and sepsis continues to increase in the United States and patients die due to failure to respond to the traditional therapies of nitric oxide blockade, adrenergic agonists, etc. Bacterial and mitochondrial N-formyl peptides (NFPs) act as damage-associated molecular patterns and activate the innate immune system through formyl peptide receptors (FPR) located in immune and non-immune cells, including the vascular endothelium. The resulting inflammatory response manifests as capillary leak, tissue hypoperfusion and vasoplegia, partially due to endothelium barrier breakdown. Potential strategies to prevent this response include decreasing NFP release, breakdown of NFPs, and blocking NFPs from binding FPR. We propose the use of deformylase, the degrading enzyme for NFPs, as potential therapeutic approach to prevent the deleterious effects of NFPs in SIRS and sepsis.

Could platelet to leucocytic count ratio (PLR) predict sepsis and clinical outcomes in patients with emphysematous pyelonephritis?

OBJECTIVES

To study risk factors for sepsis and mortality evaluating the role of platelet to leucocytic count ratio (PLR) as a marker for urosepsis and clinical outcomes in cases of emphysematous pyelonephritis (EPN).

MATERIALS

Patients with EPN were retrospectively reviewed. Patients' age, sex, diabetes mellitus (DM), Body Mass Index (BMI), hydronephrosis, types of EPN, air locules volume, serum creatinine, leucocytic count, and platelet count, PLR, albumin, INR and the line of treatment were analyzed as risk factors of sepsis. Correlation between PLR and other variables was done using Pearson correlation coefficient. Univariate and multivariate analyses for sepsis and mortality were performed.

RESULTS

Of fifty four patients, 38 patients had SIRS ≥2 criteria on admission. Twenty patients developed sepsis requiring ICU admission. In univariate analysis, male gender, lower BMI, higher INR, higher WBCs count and lower PLR were associated with sepsis (P = 0.0001, 0.009, 0.04, 0.003 and 0.001, respectively). In multivariate analysis, PLR ≤18.4, male sex and BMI ≤24.2 were independent risk factors. Lower PLR directly correlated with serum albumin (P = 0.01) and inversely correlated with serum creatinine and random blood glucose level and Klebsiella infection (P = 0.001, 0.007 and 0.005, respectively). Also, it was correlated with a higher total score of qSOFA and SOFA (P = 0.02 and 0.04). Lower PLR was independent risk factors for death in EPN patients with (P = 0.003).

CONCLUSION

EPN is associated with sepsis development. Lower PLR is an independent simple predictor for sepsis and mortality in patients with EPN.

Inflammasome Activation Triggers Blood Clotting and Host Death through Pyroptosis

Inflammasome activation and subsequent pyroptosis are critical defense mechanisms against microbes. However, overactivation of inflammasome leads to death of the host. Although recent studies have uncovered the mechanism of pyroptosis following inflammasome activation, how pyroptotic cell death drives pathogenesis, eventually leading to death of the host, is unknown. Here, we identified inflammasome activation as a trigger for blood clotting through pyroptosis. We have shown that canonical inflammasome activation by the conserved type III secretion system (T3SS) rod proteins from Gram-negative bacteria or noncanonical inflammasome activation by lipopolysaccharide (LPS) induced systemic blood clotting and massive thrombosis in tissues. Following inflammasome activation, pyroptotic macrophages released tissue factor (TF), an essential initiator of coagulation cascades. Genetic or pharmacological inhibition of TF abolishes inflammasome-mediated blood clotting and protects against death. Our data reveal that blood clotting is the major cause of host death following inflammasome activation and demonstrate that inflammasome bridges inflammation with thrombosis.

Predicting complicated outcomes in spinal cord injury patients with urinary tract infection: Development and internal validation of a risk model

CONTEXT/OBJECTIVE

Patients with chronic SCI hospitalized for UTI can have significant morbidity. It is unclear whether SIRS criteria, SOFA score, or quick SOFA score can be used to predict complicated outcome.

DESIGN

Retrospective cohort study. A risk prediction model was developed and internally validated using bootstrapping methodology.

SETTING

Urban, academic hospital in St. Louis, Missouri.

PARTICIPANTS

402 hospitalizations for UTI between October 1, 2010 and September 30, 2015, arising from 164 patients with chronic SCI, were included in the final analysis. Outcome/measures: An a priori composite complicated outcome defined as: 30-day hospital mortality, length of hospital stay >4 days, intensive care unit (ICU) admission, and hospital revisit within 30 days of discharge.

RESULTS

Mean age of patients was 46.4 ± 12.3 years; 83.6% of patient-visits involved males. The primary outcome occurred in 278 (69.2%) hospitalizations. In multivariate analysis, male sex was protective (odds ratio [OR], 0.43; 95% confidence interval [CI], 0.18-0.99; P = 0.048) while Gram-positive urine culture (OR 3.07; 95% CI, 1.05-9.01; P = 0.041), urine culture with no growth (OR, 1.69; 95% CI, 1.02-2.80; P = 0.041), and greater SOFA score (for one-point increments, OR, 1.41; 95% CI, 1.18-1.69; P < 0.001) were predictive for complicated outcome. SIRS criteria and qSOFA score were not associated with complicated outcome. Our risk prediction model demonstrated good overall performance (Brier score, 0.19), fair discriminatory power (c-index, 0.72), and good calibration during internal validation.

CONCLUSION

Clinical variables present on hospital admission with UTI may help identify SCI patients at risk for complicated outcomes and inform future clinical decision-making.

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

BACKGROUND

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

OBJECTIVES

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

SEARCH METHODS

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

SELECTION CRITERIA

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

DATA COLLECTION AND ANALYSIS

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

MAIN RESULTS

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

AUTHORS' CONCLUSIONS

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

Clinical implementation of molecular methods in detection of microorganisms from blood with a special focus on PCR electrospray ionization mass spectrometry

INTRODUCTION

The ongoing improvement and development of state-of-the-art diagnostic methods indicate that we are in an era of revolution in clinical microbiological diagnosis of infectious diseases. Non-culture-based methods have the possibility to play a central role in delivering personalized microbiological diagnoses of severe infections. The PCR electrospray ionization mass spectrometry (PCR/ESI-MS) system is built on the principle of universal detection and specific identification. The performance studies using PCR/ESI-MS on whole blood samples, as well as our experiences, indicate that this method provides useful clinical information. These types of modern molecular methods deserve further development for broad implementation into clinical practices. Areas covered: The review describes briefly hitherto developed molecular assays in detection of microorganisms directly from whole blood and focuses on the clinical implementation of PCR/ESI-MS. Expert opinion: The detection of an extensive broad-spectrum of microorganisms directly from whole blood samples with a series of tests that are run automatically with a turn-around time of 8 h would be a desirable diagnostic tool for the clinical microbiology laboratories. We believe that the clinical experience with PCR-ESI MS may guide the development and establishment of similar state-of-the-art diagnostic technologies in medicine in the future.

Circulating growth/differentiation factor 15 is associated with human CD56bright natural killer cell dysfunction and nosocomial infection in severe systemic inflammation

Background

Systemic inflammation induced by sterile or infectious insults is associated with an enhanced susceptibility to life-threatening opportunistic, mostly bacterial, infections due to unknown pathogenesis. Natural killer (NK) cells contribute to the defence against bacterial infections through the release of Interferon (IFN) γ in response to Interleukin (IL) 12. Considering the relevance of NK cells in the immune defence we investigated whether the function of NK cells is disturbed in patients suffering from serious systemic inflammation.

Methods

NK cells from severely injured patients were analysed from the first day after the initial inflammatory insult until the day of discharge in terms of IL-12 receptor signalling and IFN-γ synthesis.

Findings

During systemic inflammation, the expression of the IL-12 receptor β2 chain, phosphorylation of signal transducer and activation 4, and IFN-γ production on/in NK cells was impaired upon exposure to Staphylococcus aureus. The profound suppression of NK cells developed within 24 h after the initial insult and persisted for several weeks. NK cells displayed signs of exhaustion. Extrinsic changes were mediated by the early and long-lasting presence of growth/differentiation factor (GDF) 15 in the circulation that signalled through the transforming growth factor β receptor I and activated Smad1/5. Moreover, the concentration of GDF-15 in the serum inversely correlated with the IL-12 receptor β2 expression on NK cells and was enhanced in patients who later acquired septic complications.

Interpretation

GDF-15 is associated with the development of NK cell dysfunction during systemic inflammation and might represent a novel target to prevent nosocomial infections.

Fund

The study was supported by the Department of Orthopaedics and Trauma Surgery, University Hospital Essen.

Expression of LAIR-1 (CD305) on Human Blood Monocytes as a Marker of Hepatic Cirrhosis Progression

Background and Aim

The presumed role of the inhibitory receptor LAIR-1 (CD305) in the inflammatory response suggests that it might contribute to the pathophysiology of chronic inflammatory diseases such as liver cirrhosis. We studied the LAIR-1 expression on liver macrophages and blood monocytes related to the progression of liver cirrhosis.

Methods

The expression of LAIR-1 was analyzed by immunohistochemistry, flow cytometry, and Western blot.

Results

We found a decreased number of macrophages expressing LAIR-1 in cirrhotic liver that could be due to a high presence of collagen, ligand of LAIR-1, in the fibrotic tissue which could downregulate its expression or interfere with the immunostaining. The expression of LAIR-1 decreased after cell differentiation, and the total content, but not the cell surface expression, increased after activation in the HL-60 human macrophage in vitro model. Blood monocytes exhibited higher LAIR-1 expression levels in cirrhotic patients, which were evident even in early clinical stages in all monocyte subsets, and greater in the "intermediate" inflammatory monocyte subpopulation. The in vitro activation of human blood monocytes did not increase its expression on the cell surface suggesting that the in vivo increase of LAIR-1 must be the result of a specific combination of stimuli present in cirrhotic patients. This represents an exclusive feature of liver cirrhosis, since blood monocytes from other chronic inflammatory pathologies showed similar or lower LAIR-1 levels compared with those of healthy controls.

Conclusions

These results may indicate that monocyte LAIR-1 expression is a new biomarker to early detect liver damage caused by chronic inflammation in liver cirrhosis.

A Comparative Review of Equine SIRS, Sepsis, and Neutrophils

The most recent definition of sepsis in human medicine can be summarized as organ dysfunction caused by a dysregulated host response to infection. In equine medicine, although no consensus definition is available, sepsis is commonly described as a dysregulated host systemic inflammatory response to infection. Defense against host infection is the primary role of innate immune cells known as neutrophils. Neutrophils also contribute to host injury during sepsis, making them important potential targets for sepsis prevention, diagnosis, and treatment. This review will present both historical and updated perspectives on the systemic inflammatory response (SIRS) and sepsis; it will also discuss the impact of sepsis on neutrophils, and the impact of neutrophils during sepsis. Future identification of clinically relevant sepsis diagnosis and therapy depends on a more thorough understanding of disease pathogenesis across species. To gain this understanding, there is a critical need for research that utilizes a clearly defined, and consistently applied, classification system for patients diagnosed with, and at risk of developing, sepsis.

Protective Effects of Evodiamine against LPS-Induced Acute Kidney Injury through Regulation of ROS-NF-κB-Mediated Inflammation

Acute kidney injury (AKI) is a critical care syndrome, which is usually associated with sepsis-related endotoxemia. Evodiamine (EVO) is an active ingredient of many traditional medicinal formulations that possess a battery of biological activities. In the study, we aimed to evaluate the potential protective effect of EVO against lipopolysaccharide- (LPS-) induced AKI and cytotoxicity. LPS-resulted pathological injuries were significantly ameliorated by the administration of EVO. EVO reduced the levels of blood urea nitrogen (BUN) and creatinine in LPS-treated rats. EVO also inhibited LPS-induced reduction of cell viability in NRK-52E cells. LPS-resulting increase of TNFα and IL-1β in both serum and kidney of rats and NRK-52E cells was inhibited by EVO. LPS-induced increase of P65 NF-κB expression was markedly inhibited by EVO. EVO-induced reduction of TNFα and IL-1β expression in LPS-treated cells was blocked by overexpression of P65 NF-κB. Moreover, the increase of cell viability in LPS-treated cells induced by EVO was remarkably suppressed by overexpression of P65 NF-κB. LPS-resulting increase of reactive oxygen species (ROS) production was suppressed by EVO. H₂O₂ suppressed EVO-induced decrease of P65 NF-κB expression and increase of cell viability in LPS-treated NRK-52E cells. Moreover, the antioxidant NAC significantly promoted EVO-induced decrease of P65 NF-κB expression and increase of cell viability in LPS-treated NRK-52E cells. In conclusion, EVO had crucial protective effects against LPS-induced AKI and cytotoxicity through the antioxidant activities and thus the inhibition of inflammation. Our data highlight EVO as a potential candidate for the development of new strategies for the treatment of AKI.

Usefulness of qSOFA and SIRS scores for detection of incipient sepsis in general ward patients: A prospective cohort study

PURPOSE

To prospectively assess the diagnostic value of quick Sequential Organ Failure Assessment (qSOFA) and systemic inflammatory response syndrome (SIRS) scores for sepsis in ward patients with infections.

MATERIALS AND METHODS

Consecutive patients admitted with infection or developing infection during hospital stay were included. All variables for calculating qSOFA, SIRS, and SOFA scores were collected, and the maximum scores were determined until hospital discharge, death, or day 28, whichever occurred earlier. The primary outcome was sepsis at 28 days. Diagnostic and prognostic values were assessed using the area under the receiver operating characteristic curve (AUROC) with the conventional cutoff value of 2.

RESULTS

Of 409 general ward patients, 146 patients and 371 patients met qSOFA and SIRS criteria, 229 patients developed sepsis. Although qSOFA score had a better overall diagnostic performance of sepsis (AUROC 0.75 vs. 0.69), it had a much lower sensitivity (53% vs. 98%) and higher specificity (87% vs. 18%) than SIRS score. In addition, qSOFA score had a better prognostic value than SIRS score (AUROC 0.86 vs. 0.67).

CONCLUSIONS

Neither SIRS score nor qSOFA score could serve as an ideal screening tool for early identification sepsis, whereas qSOFA score might help to identify patients with higher risk of poor clinical outcome.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT02930070.

Time to positivity of blood cultures supports early re-evaluation of empiric broad-spectrum antimicrobial therapy

BACKGROUND

Blood cultures are considered the gold standard to distinguish bacteremia from non-bacteremic systemic inflammation. In current clinical practice, bacteraemia is considered unlikely if blood cultures have been negative for 48-72 hours. Modern BC systems have reduced this time-to-positivity (TTP), questioning whether the time frame of 48-72 hrs is still valid. This study investigates the distribution of TTP, the probability of blood culture positivity after 24 hours, and identifies clinical predictors of prolonged TTP.

METHODS

Adult patients with monomicrobial bacteremia in an academic hospital were included retrospectively over a three-year period. Clinical data were retrieved from the medical records. Predictors of TTP >24 hours were determined by uni- and multivariate analyses. The residual probability of bacteremia was estimated for the scenario of negative BCs at 24 hours after bedside collection.

RESULTS

The cohort consisted of 801 patients, accounting for 897 episodes of bacteremia. Mean age was 65 years (IQR 54-73), 534 (59.5%) patients were male. Median TTP was 15.7 (IQR 13.5-19.3) hours. TTP was ≤24 hours in 85.3% of episodes. Antibiotic pre-treatment (adjusted OR 1.77; 95%CI 1.14-2.74, p<0.01) was independently associated with prolonged TTP. The probability of bacteremia, if BC had remained negative for 24 hours, was 1.8% (95% CI 1.46-2.14).

CONCLUSION

With adequate hospital logistics, the probability of positive blood cultures after 24 hours of negative cultures was low. Combined with clinical reassessment, knowledge of this low probability may contribute to prioritization of the differential diagnosis and decisions on antimicrobial therapy. As a potential antibiotic stewardship tool, this strategy warrants further prospective investigation.

Kidney histopathology in lethal human sepsis

Purpose

The histopathology of sepsis-associated acute kidney injury (AKI) in critically ill patients remains an understudied area. Previous studies have identified that acute tubular necrosis (ATN) is not the only driver of sepsis-AKI. The focus of this study was to identify additional candidate processes that may drive sepsis-AKI. To do this we immunohistochemically characterized the histopathological and cellular features in various compartments of human septic kidneys.

Methods

We studied the following histopathological features: leukocyte subsets, fibroblast activation, cellular proliferation, apoptosis, and fibrin deposition in the glomerulus and the tubulointerstitium in human post-mortem kidney biopsy tissue. Biopsy tissue samples from 27 patients with sepsis-AKI were collected 33 min (range 24–150) after death in the ICU. The unaffected part of the kidneys from 12 patients undergoing total nephrectomy as a result of renal carcinoma served as controls.

Results

Immunohistochemical analysis revealed the presence of more neutrophils and macrophages in the glomeruli and more neutrophils in the tubulointerstitium of renal tissue from patients with sepsis compared to control renal tissue. Type II macrophages were predominant, with some macrophages expressing both type I and type II markers. In contrast, there were almost no macrophages found in control kidneys. The number of activated (myo)fibroblasts was low in the glomeruli of sepsis-AKI kidneys, yet this was not observed in the tubulointerstitium. Cell proliferation and fibrin deposition were more pronounced in the glomeruli and tubulointerstitium of sepsis-AKI than in control kidneys.

Conclusions

The extensive heterogeneity of observations among and within patients emphasizes the need to thoroughly characterize patients with sepsis-AKI in a large sample of renal biopsy tissue from patients with sepsis.

Electronic supplementary material

The online version of this article (10.1186/s13054-018-2287-3) contains supplementary material, which is available to authorized users.

Ascitic Bacterial Composition Is Associated With Clinical Outcomes in Cirrhotic Patients With Culture-Negative and Non-neutrocytic Ascites

Ascites bacterial burden is associated with poor clinical outcomes in patients with end-stage liver disease. However, the impact of ascitic microbial composition on clinical course was still not clear. In this study, the ascitic microbiota composition of 100 cirrhotic patients with culture-negative and non-neutrocytic ascites were researched with 16S rRNA pyrosequencing and enterotype-like cluster analysis. Results: By characterizing the ascitic microbial composition, two distinct microbial clusters were observed, Cluster 1 (86 patients) and Cluster 2 (14 patients). Cluster 1 showed lower microbial richness than Cluster 2. At the phylum level, Cluster 1 had greater abundance of Bacteroidetes and Firmicutes, but less abundance of Proteobacteria and Actinobacteria than Cluster 2. At the family level, family Bacteroidales S24-7 group, Prevotellaceae, Lachnospiraceae, Lactobacillaceae, Rikenellaceae, and Vibrionaceae were found over-represented in Cluster 1. And family Acetobacteraceae, Erysipelotrichaceae, Rickettsiaceae, and Streptococcaceae were found enriched in Cluster 2. The levels of plasma cytokine IL-17A, IL-7, and PDGF-BB were found significantly higher in Cluster 1 than in Cluster 2. There were four OTUs closely correlated with plasma cytokines, which were OTU 140 and OTU 271 (both from Bacteroidales S24-7 group), OTU 68 (Veillonellaceae), and OTU 53 (Helicobacteraceae). Patients from Cluster 1 showed significant higher short-term mortality than patients from Cluster 2. Conclusion: Our study demonstrated that the microbial composition of culture-negative and non-neutrocytic ascites in cirrhotic patients is associated with short-term clinical outcomes. The results here offer a rational for the identification of patients with high risk, and provide references for selective use of prophylactic methods.