Proteomic Evolution from Acute to Post-COVID-19 Conditions.

Many COVID-19 survivors have post-COVID-19 conditions, and females are at a higher risk. We sought to determine (1) how protein levels change from acute to post-COVID-19 conditions, (2) whether females have a plasma protein signature different from that of males, and (3) which biological pathways are associated with COVID-19 when compared to restrictive lung disease. We measured protein levels in 74 patients on the day of admission and at 3 and 6 months after diagnosis. We determined protein concentrations by multiple reaction monitoring (MRM) using a panel of 269 heavy-labeled peptides. The predicted forced vital capacity (FVC) and diffusing capacity of the lungs for carbon monoxide (DLCO) were measured by routine pulmonary function testing. Proteins associated with six key lipid-related pathways increased from admission to 3 and 6 months; conversely, proteins related to innate immune responses and vasoconstriction-related proteins decreased. Multiple biological functions were regulated differentially between females and males. Concentrations of eight proteins were associated with FVC, %, and they together had c-statistics of 0.751 (CI:0.732-0.779); similarly, concentrations of five proteins had c-statistics of 0.707 (CI:0.676-0.737) for DLCO, %. Lipid biology may drive evolution from acute to post-COVID-19 conditions, while activation of innate immunity and vascular regulation pathways decreased over that period. (ProteomeXchange identifiers: PXD041762, PXD029437).

Using a targeted metabolomics approach to explore differences in ARDS associated with COVID-19 compared to ARDS caused by H1N1 influenza and bacterial pneumonia.

RATIONALE: Acute respiratory distress syndrome (ARDS) is a life-threatening critical care syndrome commonly associated with infections such as COVID-19, influenza, and bacterial pneumonia. Ongoing research aims to improve our understanding of ARDS, including its molecular mechanisms, individualized treatment options, and potential interventions to reduce inflammation and promote lung repair. OBJECTIVE: To map and compare metabolic phenotypes of different infectious causes of ARDS to better understand the metabolic pathways involved in the underlying pathogenesis. METHODS: We analyzed metabolic phenotypes of 3 ARDS cohorts caused by COVID-19, H1N1 influenza, and bacterial pneumonia compared to non-ARDS COVID-19-infected patients and ICU-ventilated controls. Targeted metabolomics was performed on plasma samples from a total of 150 patients using quantitative LC-MS/MS and DI-MS/MS analytical platforms. RESULTS: Distinct metabolic phenotypes were detected between different infectious causes of ARDS. There were metabolomics differences between ARDSs associated with COVID-19 and H1N1, which include metabolic pathways involving taurine and hypotaurine, pyruvate, TCA cycle metabolites, lysine, and glycerophospholipids. ARDSs associated with bacterial pneumonia and COVID-19 differed in the metabolism of D-glutamine and D-glutamate, arginine, proline, histidine, and pyruvate. The metabolic profile of COVID-19 ARDS (C19/A) patients admitted to the ICU differed from COVID-19 pneumonia (C19/P) patients who were not admitted to the ICU in metabolisms of phenylalanine, tryptophan, lysine, and tyrosine. Metabolomics analysis revealed significant differences between C19/A, H1N1/A, and PNA/A vs ICU-ventilated controls, reflecting potentially different disease mechanisms. CONCLUSION: Different metabolic phenotypes characterize ARDS associated with different viral and bacterial infections.

Longitudinal Plasma Proteomics Analysis Reveals Novel Candidate Biomarkers in Acute COVID-19.

The host response to COVID-19 pathophysiology over the first few days of infection remains largely unclear, especially the mechanisms in the blood compartment. We report on a longitudinal proteomic analysis of acute-phase COVID-19 patients, for which we used blood plasma, multiple reaction monitoring with internal standards, and data-independent acquisition. We measured samples on admission for 49 patients, of which 21 had additional samples on days 2, 4, 7, and 14 after admission. We also measured 30 externally obtained samples from healthy individuals for comparison at baseline. The 31 proteins differentiated in abundance between acute COVID-19 patients and healthy controls belonged to acute inflammatory response, complement activation, regulation of inflammatory response, and regulation of protein activation cascade. The longitudinal analysis showed distinct profiles revealing increased levels of multiple lipid-associated functions, a rapid decrease followed by recovery for complement activation, humoral immune response, and acute inflammatory response-related proteins, and level fluctuation in the regulation of smooth muscle cell proliferation, secretory mechanisms, and platelet degranulation. Three proteins were differentiated between survivors and nonsurvivors. Finally, increased levels of fructose-bisphosphate aldolase B were determined in patients with exposure to angiotensin receptor blockers versus decreased levels in those exposed to angiotensin-converting enzyme inhibitors. Data are available via ProteomeXchange PXD029437.

Inhibition of Cholesteryl Ester Transfer Protein Preserves High-Density Lipoprotein Cholesterol and Improves Survival in Sepsis.

BACKGROUND: The high-density lipoprotein hypothesis of atherosclerosis has been challenged by clinical trials of cholesteryl ester transfer protein (CETP) inhibitors, which failed to show significant reductions in cardiovascular events. Plasma levels of high-density lipoprotein cholesterol (HDL-C) decline drastically during sepsis, and this phenomenon is explained, in part, by the activity of CETP, a major determinant of plasma HDL-C levels. We tested the hypothesis that genetic or pharmacological inhibition of CETP would preserve high-density lipoprotein levels and decrease mortality in clinical cohorts and animal models of sepsis. METHODS: We examined the effect of a gain-of-function variant in CETP (rs1800777, p.Arg468Gln) and a genetic score for decreased CETP function on 28-day sepsis survival using Cox proportional hazard models adjusted for age and sex in the UK Biobank (n=5949), iSPAAR (Identification of SNPs Predisposing to Altered Acute Lung Injury Risk; n=882), Copenhagen General Population Study (n=2068), Copenhagen City Heart Study (n=493), Early Infection (n=200), St Paul's Intensive Care Unit 2 (n=203), and Vasopressin Versus Norepinephrine Infusion in Patients With Septic Shock studies (n=632). We then studied the effect of the CETP inhibitor, anacetrapib, in adult female APOE*3-Leiden mice with or without human CETP expression using the cecal-ligation and puncture model of sepsis. RESULTS: A fixed-effect meta-analysis of all 7 cohorts found that the CETP gain-of-function variant was significantly associated with increased risk of acute sepsis mortality (hazard ratio, 1.44 [95% CI, 1.22-1.70]; P<0.0001). In addition, a genetic score for decreased CETP function was associated with significantly decreased sepsis mortality in the UK Biobank (hazard ratio, 0.77 [95% CI, 0.59-1.00] per 1 mmol/L increase in HDL-C) and iSPAAR cohorts (hazard ratio, 0.60 [95% CI, 0.37-0.98] per 1 mmol/L increase in HDL-C). APOE*3-Leiden.CETP mice treated with anacetrapib had preserved levels of HDL-C and apolipoprotein-AI and increased survival relative to placebo treatment (70.6% versus 35.3%, Log-rank P=0.03), whereas there was no effect of anacetrapib on the survival of APOE*3-Leiden mice that did not express CETP (50.0% versus 42.9%, Log-rank P=0.87). CONCLUSIONS: Clinical genetics and humanized mouse models suggest that inhibiting CETP may preserve high-density lipoprotein levels and improve outcomes for individuals with sepsis.

Renin-Angiotensin System Pathway Therapeutics Associated With Improved Outcomes in Males Hospitalized With COVID-19.

OBJECTIVES: To determine whether angiotensin receptor blockers (ARBs) or angiotensin-converting enzyme (ACE) inhibitors are associated with improved outcomes in hospitalized patients with COVID-19 according to sex and to report sex-related differences in renin-angiotensin system (RAS) components. DESIGN: Prospective observational cohort study comparing the effects of ARB or ACE inhibitors versus no ARBs or ACE inhibitors in males versus females. Severe acute respiratory syndrome coronavirus 2 downregulates ACE-2, potentially increasing angiotensin II (a pro-inflammatory vasoconstrictor). Sex-based differences in RAS dysregulation may explain sex-based differences in responses to ARBs because the ACE2 gene is on the X chromosome. We recorded baseline characteristics, comorbidities, prehospital ARBs or ACE inhibitor treatment, use of organ support and mortality, and measured RAS components at admission and days 2, 4, 7, and 14 in a subgroup ( n = 46), recorded d -dimer ( n = 967), comparing males with females. SETTING: ARBs CORONA I is a multicenter Canadian observational cohort of patients hospitalized with acute COVID-19. This analysis includes patients admitted to 10 large urban hospitals across the four most populated provinces. PATIENTS: One-thousand six-hundred eighty-six patients with polymerase chain reaction-confirmed COVID-19 (February 2020 to March 2021) for acute COVID-19 illness were included. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Males on ARBs before admission had decreased use of ventilation (adjusted odds ratio [aOR] = 0.52; p = 0.007) and vasopressors (aOR = 0.55; p = 0.011) compared with males not on ARBs or ACE inhibitors. No significant effects were observed in females for these outcomes. The test for interaction was significant for use of ventilation ( p = 0.006) and vasopressors ( p = 0.044) indicating significantly different responses to ARBs according to sex. Males had significantly higher plasma ACE-1 at baseline and angiotensin II at day 7 and 14 than females. CONCLUSIONS: ARBs use was associated with less ventilation and vasopressors in males but not females. Sex-based differences in RAS dysregulation may contribute to sex-based differences in outcomes and responses to ARBs in COVID-19.

Thermoneutral Housing and a Western Diet Combination Exacerbates Dysferlin-Deficient Muscular Dystrophy.

INTRODUCTION/AIMS: Most mouse models of muscular dystrophy (MD) show mild phenotypes, which limits the translatability of experimental therapies to patients. A growing body of evidence suggests that MD is accompanied by metabolic abnormalities that could potentially exacerbate the primary muscle wasting process. Since thermoneutral (TN) housing of mice (~30°C) has been shown to affect many metabolic parameters, particularly when combined with a Western diet (WD), our aim was to determine whether the combination of TN and WD exacerbates muscle wasting in dysferlin-deficient BLAJ mice, a common model of limb-girdle MD type 2b (LGMD2b). METHODS: The 2-mo-old wild-type (WT) and BLAJ mice were housed at TN or room temperature (RT) and fed a WD or regular chow for 9 mo. Ambulatory function, muscle histology, and protein immunoblots of skeletal muscle were assessed. RESULTS: BLAJ mice at RT and fed a chow diet showed normal ambulation function similar to WT mice, whereas 90% of BLAJ mice under WD and TN combination showed ambulatory dysfunction (p < 0.001), and an up to 4.1-fold increase in quadriceps and gastrocnemius fat infiltration. Western blotting revealed decreased autophagy marker microtubules-associated protein 1 light chain 3-B (LC3BII/LC3BI) ratio and up-regulation of protein kinase B/AKT and ribosomal protein S6 phosphorylation, suggesting inefficient cellular debris and protein clearance in TN BLAJ mice fed a WD. Male and female BLAJ mice under TN and WD combination showed heterogenous fibro-fatty infiltrate composition. DISCUSSION: TN and WD combination exacerbates rodent LGMD2b without affecting WT mice. This improves rodent modeling of human MD and helps elucidate how metabolic abnormalities may play a causal role in muscle wasting.

Acute Cardiac Injury in Coronavirus Disease 2019 and Other Viral Infections-A Systematic Review and Meta-Analysis.

OBJECTIVES: Severe acute respiratory syndrome-related coronavirus-2 binds and inhibits angiotensin-converting enzyme-2. The frequency of acute cardiac injury in patients with coronavirus disease 2019 is unknown. The objective was to compare the rates of cardiac injury by angiotensin-converting enzyme-2-binding viruses from viruses that do not bind to angiotensin-converting enzyme-2. DATA SOURCES: We performed a systematic review of coronavirus disease 2019 literature on PubMed and EMBASE. STUDY SELECTION: We included studies with ten or more hospitalized adults with confirmed coronavirus disease 2019 or other viral pathogens that described the occurrence of acute cardiac injury. This was defined by the original publication authors or by: 1) myocardial ischemia, 2) new cardiac arrhythmia on echocardiogram, or 3) new or worsening heart failure on echocardiogram. DATA EXTRACTION: We compared the rates of cardiac injury among patients with respiratory infections with viruses that down-regulate angiotensin-converting enzyme-2, including H1N1, H5N1, H7N9, and severe acute respiratory syndrome-related coronavirus-1, to those with respiratory infections from other influenza viruses that do not bind angiotensin-converting enzyme-2, including Influenza H3N2 and influenza B. DATA SYNTHESIS: Of 57 studies including 34,072 patients, acute cardiac injury occurred in 50% (95% CI, 44-57%) of critically ill patients with coronavirus disease 2019. The overall risk of acute cardiac injury was 21% (95% CI, 18-26%) among hospitalized patients with coronavirus disease 2019. In comparison, 37% (95% CI, 26-49%) of critically ill patients with other respiratory viruses that bind angiotensin-converting enzyme-2 (p = 0.061) and 12% (95% CI, 7-22%) of critically ill patients with other respiratory viruses that do not bind angiotensin-converting enzyme-2 (p < 0.001) experienced a cardiac injury. CONCLUSIONS: Acute cardiac injury may be associated with whether the virus binds angiotensin-converting enzyme-2. Acute cardiac injury occurs in half of critically ill coronavirus disease 2019 patients, but only 12% of patients infected by viruses that do not bind to angiotensin-converting enzyme-2.

Causal Inference for Genetically Determined Levels of High-Density Lipoprotein Cholesterol and Risk of Infectious Disease.

OBJECTIVE: HDL (high-density lipoprotein) cholesterol (HDL-C) and LDL (low-density lipoprotein) cholesterol (LDL-C) are inversely associated with infectious hospitalizations. Whether these represent causal relationships is unknown. Approach and Results: Adults of 40 to 69 years of age were recruited from across the United Kingdom between 2006 and 2010 and followed until March 31, 2016, as part of the UK Biobank. We determined HDL-C, LDL-C, and triglyceride polygenic scores for UK Biobank participants of British white ancestry (n=407 558). We examined the association of lipid levels and polygenic scores with infectious hospitalizations, antibiotic usage, and 28-day sepsis survival using Cox proportional hazards or logistic regression models. Measured levels of HDL-C and LDL-C were inversely associated with risk of infectious hospitalizations, while triglycerides displayed a positive association. A 1-mmol/L increase in genetically determined levels of HDL-C associated with a hazard ratio for infectious disease of 0.84 ([95% CI, 0.75-0.95]; P=0.004). Mendelian randomization using genetic variants associated with HDL-C as an instrumental variable was consistent with a causal relationship between elevated HDL-C and reduced risk of infectious hospitalizations (inverse weighted variance method, P=0.001). Furthermore, of 3222 participants who experienced an index episode of sepsis, there was a significant inverse association between continuous HDL-C polygenic score and 28-day mortality (adjusted hazard ratio, 0.37 [95% CI, 0.14-0.96] per 1 mmol/L increase; P=0.04). LDL-C and triglyceride polygenic scores were not significantly associated with hospitalization for infection, antibiotic use, or sepsis mortality. CONCLUSIONS: Our results provide causal inference for an inverse relationship between HDL-C, but not LDL-C or triglycerides, and risk of an infectious hospitalization.

Vasopressor Therapy in the Intensive Care Unit.

After fluid administration for vasodilatory shock, vasopressors are commonly infused. Causes of vasodilatory shock include septic shock, post-cardiovascular surgery, post-acute myocardial infarction, postsurgery, other causes of an intense systemic inflammatory response, and drug -associated anaphylaxis. Therapeutic vasopressors are hormones that activate receptors-adrenergic: α1, α2, ß1, ß2; angiotensin II: AG1, AG2; vasopressin: AVPR1a, AVPR1B, AVPR2; dopamine: DA1, DA2. Vasopressor choice and dose vary widely because of patient and physician practice heterogeneity. Vasopressor adverse effects are excessive vasoconstriction causing organ ischemia/infarction, hyperglycemia, hyperlactatemia, tachycardia, and tachyarrhythmias. To date, no randomized controlled trial (RCT) of vasopressors has shown a decreased 28-day mortality rate. There is a need for evidence regarding alternative vasopressors as first-line vasopressors. We emphasize that vasopressors should be administered simultaneously with fluid replacement to prevent and decrease duration of hypotension in shock with vasodilation. Norepinephrine is the first-choice vasopressor in septic and vasodilatory shock. Interventions that decrease norepinephrine dose (vasopressin, angiotensin II) have not decreased 28-day mortality significantly. In patients not responsive to norepinephrine, vasopressin or epinephrine may be added. Angiotensin II may be useful for rapid resuscitation of profoundly hypotensive patients. Inotropic agent(s) (e.g., dobutamine) may be needed if vasopressors decrease ventricular contractility. Dopamine has fallen to almost no-use recommendation because of adverse effects; angiotensin II is available clinically; there are potent vasopressors with scant literature (e.g., methylene blue); and the novel V1a agonist selepressin missed on its pivotal RCT primary outcome. In pediatric septic shock, vasopressors, epinephrine, and norepinephrine are recommended equally because there is no clear evidence that supports the use of one vasoactive agent. Dopamine is recommended when epinephrine or norepinephrine is not available. New strategies include perhaps patients will be started on several vasopressors with complementary mechanisms of action, patients may be selected for particular vasopressors according to predictive biomarkers, and novel vasopressors may emerge with fewer adverse effects.

Squamous Cell Carcinoma Arising in Breast Implant Capsules.

ABSTRACT: Breast augmentation and reconstruction utilizing implants are among the most common plastic surgery procedures performed in the United States. A small proportion of these implants are removed each year. We report 2 cases where routine pathologic evaluation of capsulectomy specimens revealed squamous cell carcinoma associated with the breast implant capsule and discuss the possible pathogenesis of this unusual entity. Both patients had long-standing implants (>10 years) and presented with acute unilateral breast erythema and swelling. Intraoperatively, the capsules for both cases appeared thickened and calcified, containing extensive granulomatosis and keratinaceous debris invading into the chest wall. Extensive workup failed to find an occult primary. One patient died from a malignant pleural effusion secondary to tumor invasion during chemotherapy, and the second patient obtained stabilization of the mass after 5 weeks of chemotherapy but subsequently declined further surgical intervention. A thorough literature review was performed, and 5 similar reports were identified, involving 6 patients. All patients presented with similar clinical presentations as ours and had poor outcomes. The mean reporting age at diagnosis was 60 years, and the average time from initial implant to diagnosis was 25 years. Due to the small numbers of squamous cell carcinomas associated with breast implant capsules, the true association between the 2 is unknown. It is postulated that chronic inflammation/irritation from the breast implant and epithelialization of the capsule play a significant role in the disease process. This may represent a new entity of "chronic inflammatory capsular malignancies." Increased awareness of this entity may allow for earlier suspicion, diagnosis, and management.

Very Low Density Lipoprotein Receptor Sequesters Lipopolysaccharide Into Adipose Tissue During Sepsis.

OBJECTIVES: Obese patients have lower sepsis mortality termed the "obesity paradox." We hypothesized that lipopolysaccharide, known to be carried within lipoproteins such as very low density lipoprotein, could be sequestered in adipose tissue during sepsis; potentially contributing a survival benefit. DESIGN: Retrospective analysis. SETTING: University research laboratory. SUBJECTS AND PATIENTS: Vldlr knockout mice to decrease very low density lipoprotein receptors, Pcsk9 knockout mice to increase very low density lipoprotein receptor, and Ldlr knockout mice to decrease low density lipoprotein receptors. Differentiated 3T3-L1 adipocytes. Caucasian septic shock patients. INTERVENTIONS: We measured lipopolysaccharide uptake into adipose tissue 6 hours after injection of fluorescent lipopolysaccharide into mice. Lipopolysaccharide uptake and very low density lipoprotein receptor protein expression were measured in adipocytes. To determine relevance to humans, we genotyped the VLDLR rs7852409 G/C single-nucleotide polymorphism in 519 patients and examined the association of 28-day survival with genotype. MEASUREMENTS AND MAIN RESULTS: Lipopolysaccharide injected into mice was found in adipose tissue within 6 hours and was dependent on very low density lipoprotein receptor but not low density lipoprotein receptors. In an adipocyte cell line decreased very low density lipoprotein receptor expression resulted in decreased lipopolysaccharide uptake. In septic shock patients, the minor C allele of VLDLR rs7852409 was associated with increased survival (p = 0.010). Previously published data indicate that the C allele is a gain-of-function variant of VLDLR which may increase sequestration of very low density lipoprotein (and lipopolysaccharide within very low density lipoprotein) into adipose tissue. When body mass index less than 25 this survival effect was accentuated and when body mass index greater than or equal to 25 this effect was diminished suggesting that the effect of variation in very low density lipoprotein receptor function is overwhelmed when copious adipose tissue is present. CONCLUSIONS: Lipopolysaccharide may be sequestered in adipose tissue via the very low density lipoprotein receptor and this sequestration may contribute to improved sepsis survival.

Cholesteryl Ester Transfer Protein Influences High-Density Lipoprotein Levels and Survival in Sepsis.

RATIONALE: High-density lipoprotein (HDL) cholesterol (HDL-C) levels decline during sepsis, and lower levels are associated with worse survival. However, the genetic mechanisms underlying changes in HDL-C during sepsis, and whether the relationship with survival is causative, are largely unknown. OBJECTIVES: We hypothesized that variation in genes involved in HDL metabolism would contribute to changes in HDL-C levels and clinical outcomes during sepsis. METHODS: We performed targeted resequencing of HDL-related genes in 200 patients admitted to an emergency department with sepsis (Early Infection cohort). We examined the association of genetic variants with HDL-C levels, 28-day survival, 90-day survival, organ dysfunction, and need for vasopressor or ventilatory support. Candidate variants were further assessed in the VASST (Vasopressin versus Norepinephrine Infusion in Patients with Septic Shock Trial) cohort (n = 632) and St. Paul's Hospital Intensive Care Unit 2 (SPHICU2) cohort (n = 203). MEASUREMENTS AND MAIN RESULTS: We identified a rare missense variant in CETP (cholesteryl ester transfer protein gene; rs1800777-A) that was associated with significant reductions in HDL-C levels during sepsis. Carriers of the A allele (n = 10) had decreased survival, more organ failure, and greater need for organ support compared with noncarriers. We replicated this finding in the VASST and SPHICU2 cohorts, in which carriers of rs1800777-A (n = 35 and n = 12, respectively) had significantly reduced 28-day survival. Mendelian randomization was consistent with genetically reduced HDL levels being a causal factor for decreased sepsis survival. CONCLUSIONS: Our results identify CETP as a critical regulator of HDL levels and clinical outcomes during sepsis. These data point toward a critical role for HDL in sepsis.

Variability in deceased donor care in Canada: a report of the Canada-DONATE cohort study.

PURPOSE: Canadian donor management practices have not been reported. Our aim was to inform clinicians and other stakeholders about the range of current practices. METHODS: This prospective observational cohort study enrolled consecutive, newly consented organ donors from August 1 2015 to July 31 2018 at 27 academic and five community adult intensive care units in British Columbia, Alberta, Ontario, and Quebec. Research staff prospectively recorded donor management data. Provincial organ donation organizations verified the organs donated. We formally compared practices across provinces. RESULTS: Over a median collection period of eight months, 622 potential donors were classified at baseline as having neurologic determination of death (NDD donors; n = 403) or circulatory death (DCD donors; n = 219). Among NDD donors, 85.6% underwent apnea testing (rarely with carbon dioxide insufflation), 33.2% underwent ancillary testing, and subsequent therapeutic hypothermia (34-35°C) was rare. Neurologic determination of death donors were more hemodynamically unstable with most having received vasopressin and norepinephrine infusions, with a large majority having received high-dose corticosteroids and intravenous thyroxine. Among DCD donors, 61.6% received corticosteroids, and 8.9% received thyroxine. Most donors did not receive lung-protective ventilation strategies. Invasive procedures after donation consent included bronchoscopy (71.7%), cardiac catheterization (NDD donors only; 21.3%), and blood transfusions (19.3%). Physicians ordered intravenous antemortem heparin for 94.8% of DCD donors. The cohort donated 1,629 organs resulting in 1,532 transplants. Case selection, death determinations, and hormone, nutrition and heparin practices all varied across provinces. CONCLUSION: These study findings highlight areas for knowledge translation and further clinical research. Interprovincial discrepancies will likely pose unique challenges to national randomized trials. TRIAL REGISTRATION: www.clinicaltrials.gov (NCT03114436); registered 10 April, 2017.

RéSUMé: OBJECTIF: Les pratiques canadiennes de prise en charge des donneurs n'ont pas été rapportées. Notre objectif était d'informer les cliniciens et autres parties intéressées quant à l'éventail des pratiques actuelles. MéTHODE: Cette étude de cohorte observationnelle et prospective a recruté des donneurs d'organes consécutifs ayant récemment consenti au don entre le 1er août 2015 et le 31 juillet 2018 dans 27 unités de soins intensifs universitaires et cinq unités de soins intensifs pour adultes en milieu communautaire en Colombie-Britannique, en Alberta, en Ontario et au Québec. Le personnel de recherche a enregistré de manière prospective les données de prise en charge des donneurs. Les organismes de dons d'organes provinciaux ont vérifié les organes donnés. Nous avons formellement comparé les pratiques d'une province à l'autre. RéSULTATS: Sur une période médiane de collecte de huit mois, 622 donneurs potentiels ont été catégorisés au départ comme ayant un diagnostic de décès neurologique (donneurs DDN; n = 403) ou un décès cardiocirculatoire (donneurs DDC; n = 219). Parmi les donneurs DDN, 85,6 % ont subi un test d'apnée (rarement avec insufflation de dioxyde de carbone), 33,2 % ont subi des tests complémentaires, et une hypothermie thérapeutique subséquente (34-35°C) était rare. Les donneurs par diagnostic de décès neurologique étaient plus instables hémodynamiquement, la plupart ayant reçu des perfusions de vasopressine et de norépinéphrine, et une vaste majorité de ces donneurs ont reçu des corticostéroïdes à forte dose ainsi que de la thyroxine intraveineuse. Parmi les donneurs par DDC, 61,6 % avaient reçu des corticostéroïdes, et 8,9 % de la thyroxine. La plupart des donneurs n'avaient pas bénéficié de stratégies de ventilation protectrice des poumons. Les interventions invasives réalisées après le consentement au don comprenaient la bronchoscopie (71,7 %), le cathétérisme cardiaque (donneurs DDN seulement; 21,3 %) et les transfusions sanguines (19,3 %). Les médecins ont prescrit de l'héparine intraveineuse ante mortem chez 94,8 % des donneurs DDC. La cohorte a donné 1629 organes, résultant en 1532 greffes. La sélection de cas, la détermination de décès et les pratiques hormonales, nutritionnelles et hépariniques variaient toutes d'une province à l'autre. CONCLUSION: Ces résultats soulignent des domaines propices à la transmission de connaissances et aux recherches cliniques plus poussées. Les différences interprovinciales poseront probablement des défis uniques pour les études randomisées nationales. Enregistrement de l'étude : www.clinicaltrials.gov (NCT03114436); enregistrée le 10 avril 2017.

Molecular regulation of plasma lipid levels during systemic inflammation and sepsis.

PURPOSE OF REVIEW: Sepsis is a common syndrome of multiorgan system dysfunction caused by a dysregulated inflammatory response to an infection and is associated with high rates of mortality. Plasma lipid and lipoprotein levels and composition change profoundly during sepsis and have emerged as both biomarkers and potential therapeutic targets for this condition. The purpose of this article is to review recent progress in the understanding of the molecular regulation of lipid metabolism during sepsis. RECENT FINDINGS: Patients who experience greater declines in high-density lipoprotein during sepsis are at much greater risk of succumbing to organ failure and death. Although the causality of these findings remains unclear, all lipoprotein classes can sequester and prevent the excessive inflammation caused by pathogen-associated lipids during severe infections such as sepsis. This primordial innate immune function has been best characterized for high-density lipoproteins. Most importantly, results from human genetics and preclinical animal studies have suggested that several lipid treatment strategies, initially designed for atherosclerosis, may hold promise as therapies for sepsis. SUMMARY: Lipid and lipoprotein metabolism undergoes significant changes during sepsis. An improved understanding of the molecular regulation of these changes may lead to new opportunities for the treatment of sepsis.

Low Low-Density Lipoprotein Levels Are Associated With, But Do Not Causally Contribute to, Increased Mortality in Sepsis.

OBJECTIVES: Low low-density lipoprotein levels are associated with increased mortality in sepsis. Whether low low-density lipoprotein levels contribute causally to adverse sepsis outcome is unknown. DESIGN: Retrospective analysis of two sepsis patient cohorts using a Mendelian Randomization strategy. SETTING: Sepsis patients enrolled into clinical research cohorts at tertiary care teaching hospitals. PATIENTS: The first cohort included 200 sepsis patients enrolled in an observational study in a hospital Emergency Department. The second cohort included genotyped patients enrolled in the Vasopressin and Septic Shock Trial. INTERVENTIONS: Retrospective analysis of these patient datasets. In 632 patients enrolled in Vasopressin and Septic Shock Trial, Proprotein Convertase Subtilisin/Kexin type 9, and 3-Hydroxy-3-Methylglutaryl-CoA Reductase single nucleotide polymorphisms known to be associated with low-density lipoprotein levels were genotyped, and a genetic score related to low-density lipoprotein levels was calculated. MEASUREMENTS AND MAIN RESULTS: In the first cohort, we replicated the finding that low low-density lipoprotein levels are associated with increased 28-day mortality. In genotyped patients in the Vasopressin and Septic Shock Trial trial, we found that the 3-Hydroxy-3-Methylglutaryl-CoA Reductase genetic score, known to be directly related to low low-density lipoprotein levels, was not associated with increased mortality. Surprisingly the Proprotein Convertase Subtilisin/Kexin type 9 genetic score, known to be directly related to low low-density lipoprotein levels, was associated with decreased (not increased) mortality. CONCLUSIONS: Both 3-Hydroxy-3-Methylglutaryl-CoA Reductase and Proprotein Convertase Subtilisin/Kexin type 9 genetic scores should have been associated with increased mortality if low low-density lipoprotein levels contributed causally to sepsis mortality. But this was not the case, and the opposite was observed for the Proprotein Convertase Subtilisin/Kexin type 9 genetic score. This suggests that low-density lipoprotein levels, per se, do not contribute causally to adverse sepsis outcomes. The Proprotein Convertase Subtilisin/Kexin type 9 genetic score finding raises the possibility that increased low-density lipoprotein clearance (the effect of these Proprotein Convertase Subtilisin/Kexin type 9 genotypes) may contribute to improved sepsis outcomes.

Is Heparin-Binding Protein Inhibition a Mechanism of Albumin's Efficacy in Human Septic Shock?

OBJECTIVES: Our objectives were to determine first whether albumin prevents heparin-binding protein-induced increased endothelial cell permeability and renal cell inflammation and second, whether a plasma heparin-binding protein-to-albumin ratio predicts risk of acute kidney injury, fluid balance, and plasma cytokine levels in septic shock. DESIGN: In vitro human endothelial and renal cell model and observation cohort of septic shock. SETTINGS: Research laboratory and multicenter clinical trial (Vasopressin and Septic Shock Trial). PATIENTS: Adult septic shock (norepinephrine dose > 5 µg/min for > 6 hr). INTERVENTIONS: In vitro: heparin-binding protein (or thrombin) was added with or without albumin to 1) human endothelial cell monolayers to assess permeability and 2) to human renal tubular epithelial cells to assess inflammation. MEASUREMENTS AND MAIN RESULTS: Transendothelial electrical resistance-a marker of permeability-of human endothelial cells was measured using a voltohmmeter. We measured plasma heparin-binding protein-to-albumin ratio and a panel of cytokines in septic shock patients (n = 330) to define an heparin-binding protein-to-albumin ratio that predicts risk of acute kidney injury. Albumin inhibited heparin-binding protein (and thrombin-induced) increased endothelial cell permeability at a threshold concentration of 20-30 g/L but increased renal tubular cell interleukin-6 release. Patients who developed or had worsened acute kidney injury had significantly higher heparin-binding protein-to-albumin ratio (1.6 vs 0.89; p < 0.001) and heparin-binding protein (38.2 vs 20.8 ng/mL; p < 0.001) than patients without acute kidney injury. The highest heparin-binding protein-to-albumin ratio (> 3.05), heparin-binding protein quartiles (> 69.8), and heparin-binding protein > 30 ng/mL were significantly associated with development or worsening of acute kidney injury (p < 0.001) in unadjusted and adjusted analyses and were robust to sensitivity analyses for death as a competing outcome. Heparin-binding protein and heparin-binding protein-to-albumin ratio were directly associated with positive fluid balance (p < 0.001) and with key inflammatory cytokines. Increasing quartiles of heparin-binding protein-to-albumin ratio and heparin-binding protein (but not albumin) were highly significantly associated with days alive and free of acute kidney injury and renal replacement therapy (p < 0.001), vasopressors (p < 0.001), ventilation (p < 0.001), and with 28-day mortality. CONCLUSIONS: Albumin inhibits heparin-binding protein-induced increased human endothelial cell permeability and heparin-binding protein greater than 30 ng/mL and heparin-binding protein-to-albumin ratio greater than 3.01-but not serum albumin-identified patients at increased risk for acute kidney injury in septic shock.

Survival benefit of a low ratio of visceral to subcutaneous adipose tissue depends on LDL clearance versus production in sepsis.

BACKGROUND: Patients with sepsis with a high ratio of visceral adipose tissue (VAT) to subcutaneous adipose tissue (SAT) have increased mortality. Our goal was to investigate the mechanism of this effect, noting that low LDL levels are also associated with increased sepsis mortality. Accordingly we tested for association between VAT/SAT, low-density lipoprotein (LDL) levels, and mortality. Then we examined the effect of statin treatment, which decreases LDL production, and the effect of PCSK9 genotype, which increases LDL clearance. METHODS: We performed retrospective analysis of a cohort of patients with sepsis from a tertiary care adult intensive care unit in Vancouver, Canada, who underwent abdominal computed tomography (CT) (n = 75) for clinical reasons. We compared LDL levels in patients with sepsis according to high versus low VAT/SAT and 90-day survival. We next examined the effects of statin therapy and PCSK9 loss-of-function genotype on survival. RESULTS: Patients with a low VAT/SAT had increased 90-day survival and were relatively protected against low LDL levels in sepsis compared to high VAT/SAT. Statin treatment abrogated the beneficial effects of low VAT/SAT; eliminating the difference in LDL levels and survival between patients with low and high VAT/SAT. PSCK9 loss-of-function genotype similarly eliminated the increased LDL levels in low VAT/SAT patients but, in contrast, increased the survival advantage of low VAT/SAT compared to high VAT/SAT. CONCLUSIONS: Low LDL levels per se are not simply associated with decreased sepsis survival because lowering LDL levels by inhibiting LDL production (statin treatment) is associated with adverse outcomes, while increased LDL clearance (PCSK9 loss-of-function genotype) is associated with improved outcomes in patients with low VAT/SAT.

Association of Household Income Level and In-Hospital Mortality in Patients With Sepsis: A Nationwide Retrospective Cohort Analysis.

OBJECTIVE: Associations between low socioeconomic status (SES) and poor health outcomes have been demonstrated in a variety of conditions. However, the relationship in patients with sepsis is not well described. We investigated the association of lower household income with in-hospital mortality in patients with sepsis across the United States. METHODS: Retrospective nationwide cohort analysis utilizing the Nationwide Inpatient Sample (NIS) from 2011. Patients aged 18 years or older with sepsis were included. Socioeconomic status was approximated by the median household income of the zip code in which the patient resided. Multivariate logistic modeling incorporating a validated illness severity score for sepsis in administrative data was performed. RESULTS: A total of 8 023 590 admissions from the 2011 NIS were examined. A total of 671 858 patients with sepsis were included in the analysis. The lowest income residents compared to the highest were younger (66.9 years, standard deviation [SD] = 16.5 vs 71.4 years, SD = 16.1, P < .01), more likely to be female (53.5% vs 51.9%, P < .01), less likely to be white (54.6% vs 76.6%, P < .01), as well as less likely to have health insurance coverage (92.8% vs 95.9%, P < .01). After controlling for severity of sepsis, residing in the lowest income quartile compared to the highest quartile was associated with a higher risk of mortality (odds ratio [OR]: 1.06, 95% confidence interval [CI]: 1.03-1.08, P < .01). There was no association seen between the second (OR: 1.02, 95% CI: 0.99-1.05, P = .14) and third (OR: 0.99, 95% CI: 0.97-1.01, P = .40) quartiles compared to the highest. CONCLUSION: After adjustment for severity of illness, patients with sepsis who live in the lowest median income quartile had a higher risk of mortality compared to residents of the highest income quartile. The association between SES and mortality in sepsis warrants further investigation with more comprehensive measures of SES.

The Septic Shock 3.0 Definition and Trials: A Vasopressin and Septic Shock Trial Experience.

OBJECTIVES: The Septic Shock 3.0 definition could alter treatment comparisons in randomized controlled trials in septic shock. Our first hypothesis was that the vasopressin versus norepinephrine comparison and 28-day mortality of patients with Septic Shock 3.0 definition (lactate > 2 mmol/L) differ from vasopressin versus norepinephrine and mortality in Vasopressin and Septic Shock Trial. Our second hypothesis was that there are differences in plasma cytokine levels in Vasopressin and Septic Shock Trial for lactate less than or equal to 2 versus greater than 2 mmol/L. DESIGN: Retrospective analysis of randomized controlled trial. SETTING: Multicenter ICUs. METHODS: We compared vasopressin-to-norepinephrine group 28- and 90-day mortality in Vasopressin and Septic Shock Trial in lactate subgroups. We measured 39 cytokines to compare patients with lactate less than or equal to 2 versus greater than 2 mmol/L. PATIENTS: Patients with septic shock with lactate greater than 2 mmol/L or less than or equal to 2 mmol/L, randomized to vasopressin or norepinephrine. INTERVENTIONS: Concealed vasopressin (0.03 U/min.) or norepinephrine infusions. MEASUREMENTS AND MAIN RESULTS: The Septic Shock 3.0 definition would have decreased sample size by about half. The 28- and 90-day mortality rates were 10-12 % higher than the original Vasopressin and Septic Shock Trial mortality. There was a significantly (p = 0.028) lower mortality with vasopressin versus norepinephrine in lactate less than or equal to 2 mmol/L but no difference between treatment groups in lactate greater than 2 mmol/L. Nearly all cytokine levels were significantly higher in patients with lactate greater than 2 versus less than or equal to 2 mmol/L. CONCLUSIONS: The Septic Shock 3.0 definition decreased sample size by half and increased 28-day mortality rates by about 10%. Vasopressin lowered mortality versus norepinephrine if lactate was less than or equal to 2 mmol/L. Patients had higher plasma cytokines in lactate greater than 2 versus less than or equal to 2 mmol/L, a brisker cytokine response to infection. The Septic Shock 3.0 definition and our findings have important implications for trial design in septic shock.