Interleukin-6 drives endothelial glycocalyx damage in COVID-19 and bacterial sepsis

Damage of the endothelial glycocalyx (eGC) plays a central role in the development of vascular hyperpermeability and organ damage during systemic inflammation. However, the specific signalling pathways for eGC damage remain poorly defined. Aim of this study was to combine sublingual video-microscopy, plasma proteomics and live cell imaging to uncover further pathways of eGC damage in patients with coronavirus disease 2019 (COVID-19) or bacterial sepsis. This secondary analysis of the prospective multicenter MICROCODE study included 22 patients with COVID-19 and 43 patients with bacterial sepsis admitted to intermediate or intensive care units and 10 healthy controls. Interleukin-6 (IL-6) was strongly associated with damaged eGC and correlated both with eGC dimensions (rs=0.36, p = 0.0015) and circulating eGC biomarkers. In vitro, IL-6 reduced eGC height and coverage, which was inhibited by blocking IL-6 signalling with the anti-IL-6 receptor antibody tocilizumab or the Janus kinase inhibitor tofacitinib. Exposure of endothelial cells to 5% serum from COVID-19 or sepsis patients resulted in a significant decrease in eGC height, which was attenuated by co-incubation with tocilizumab. In an external COVID-19 cohort of 219 patients from Massachusetts General Hospital, a previously identified proteomic eGC signature correlated with IL-6 (rs=-0.58, p < 0.0001) and predicted the combined endpoint of 28-day mortality and/or intubation (ROC-AUC: 0.86 [95% CI: 0.81-0.91], p < 0.001). The data suggest that IL-6 may significantly drive eGC damage in COVID-19 and bacterial sepsis. Our findings provide valuable insights into pathomechanisms of vascular dysfunction during systemic inflammation and highlight the need for further in vivo studies.

Analysis of Urinary Glycosaminoglycans to Predict Outcome in COVID-19 and Community-Acquired Pneumonia-A Proof-of-Concept Study

Although coronavirus disease 2019 (COVID-19) is considered a systemic disease associated with vascular inflammation and eventual destruction of the protective endothelial glycocalyx (eGC), biomarkers of eGC damage are not yet available in the clinic. The most prominent components of eGC are sulphated glycosaminoglycans (sGAGs) attached to core proteoglycans. We hypothesised that the amount of sGAG fragments shed in urine (as a surrogate for systemic eGC damage) would correlate with disease severity and outcome. Total urinary sGAG concentration was measured using an in-house optimised 1,9-dimethylmethylene blue (DMMB) assay, which is highly accurate and insensitive to interferences. The median urinary sGAG concentration was significantly higher in 67 hospitalised patients with COVID-19 compared to 72 hospitalised patients with community-acquired pneumonia (CAP). In both groups, urinary sGAG concentrations predicted a combined endpoint (including intubation and death) with an area under the receiver operator characteristic curve of 0.72 (95% CI 0.55-0.88, p = 0.01) and 0.70 (95% CI 0.57-0.83, p = 0.007), respectively. In conclusion, the inexpensive and easy-to-perform DMMB assay provides a surrogate parameter for eGC damage that may be useful for risk stratification of patients with COVID-19 and CAP.

Impaired humoral immunity to BQ.1.1 in convalescent and vaccinated patients

Determining SARS-CoV-2 immunity is critical to assess COVID-19 risk and the need for prevention and mitigation strategies. We measured SARS-CoV-2 Spike/Nucleocapsid seroprevalence and serum neutralizing activity against Wu01, BA.4/5 and BQ.1.1 in a convenience sample of 1,411 patients receiving medical treatment in the emergency departments of five university hospitals in North Rhine-Westphalia, Germany, in August/September 2022. 62% reported underlying medical conditions and 67.7% were vaccinated according to German COVID-19 vaccination recommendations (13.9% fully vaccinated, 54.3% one booster, 23.4% two boosters). We detected Spike-IgG in 95.6%, Nucleocapsid-IgG in 24.0%, and neutralization against Wu01, BA.4/5 and BQ.1.1 in 94.4%, 85.0%, and 73.8% of participants, respectively. Neutralization against BA.4/5 and BQ.1.1 was 5.6- and 23.4-fold lower compared to Wu01. Accuracy of S-IgG detection for determination of neutralizing activity against BQ.1.1 was reduced substantially. We explored previous vaccinations and infections as correlates of BQ.1.1 neutralization using multivariable and Bayesian network analyses. Given a rather moderate adherence to COVID-19 vaccination recommendations, this analysis highlights the need to improve vaccine-uptake to reduce the COVID-19 risk of immune evasive variants. The study was registered as clinical trial (DRKS00029414).

Resuscitation room management of patients with non-traumatic critical illness in the emergency department (OBSERvE-DUS-study)

BACKGROUND

Few studies address the care of critically ill non-traumatic patients in the emergency department (ED). The aim of this study was to assess the epidemiology, management, and outcome of these patients.

METHODS

In this retrospective study, we identified and analyzed data from all consecutive adult critically ill non-traumatic ED patients treated from March 2018 to February 2019. Patient characteristics, major complaint leading to admission, out-of-hospital, and in-hospital interventions and 30-day mortality were extracted from medical records of the electronic patient data management system.

RESULTS

During the study period, we analyzed 40,764 patients admitted to the ED. Of these, 621 (1.5%) critically ill non-traumatic patients were admitted for life-threatening emergencies to the resuscitation room (age: 70 ± 16 years, 52% male). Leading problem on admission was disability/unconsciousness (D), shock (C), respiratory failure (B), airway obstruction (A), and environment problems (E) in 41%, 31%, 25%, 2%, and 1%, respectively. Out-of-hospital and in-hospital measures included: intravenous access (61% vs. 99%), 12-lead ECG (55% vs. 87%), invasive airway management (21% vs. 34%) invasive ventilation (21% vs. 34%), catecholamines (9% vs. 30%), arterial access (0% vs. 52%), and cardiopulmonary resuscitation (11% vs. 6%). The underlying diagnoses were mainly neurological (29%), followed by cardiological (28%), and pulmonological (20%) emergencies. The mean length of stay (LOS) in the resuscitation room and ED was 123 ± 122 and 415 ± 479 min, respectively. The 30-day mortality was 18.5%.

CONCLUSION

The data describe the care of critically ill non-traumatic patients in the resuscitation room. Based on these data, algorithms for the structured care of critically ill non-traumatic patients need to be developed.

Persistent capillary rarefication in long COVID syndrome

BACKGROUND

Recent studies have highlighted Coronavirus disease 2019 (COVID-19) as a multisystemic vascular disease. Up to 60% of the patients suffer from long-term sequelae and persistent symptoms even 6 months after the initial infection.

METHODS

This prospective, observational study included 58 participants, 27 of whom were long COVID patients with persistent symptoms > 12 weeks after recovery from PCR-confirmed SARS-CoV-2 infection. Fifteen healthy volunteers and a historical cohort of critically ill COVID-19 patients (n = 16) served as controls. All participants underwent sublingual videomicroscopy using sidestream dark field imaging. A newly developed version of Glycocheck™ software was used to quantify vascular density, perfused boundary region (PBR-an inverse variable of endothelial glycocalyx dimensions), red blood cell velocity (VRBC) and the microvascular health score (MVHS™) in sublingual microvessels with diameters 4-25 µm.

MEASUREMENTS AND MAIN RESULTS

Although dimensions of the glycocalyx were comparable to those of healthy controls, a µm-precise analysis showed a significant decrease of vascular density, that exclusively affected very small capillaries (D5: - 45.16%; D6: - 35.60%; D7: - 22.79%). Plotting VRBC of capillaries and feed vessels showed that the number of capillaries perfused in long COVID patients was comparable to that of critically ill COVID-19 patients and did not respond adequately to local variations of tissue metabolic demand. MVHS was markedly reduced in the long COVID cohort (healthy 3.87 vs. long COVID 2.72 points; p = 0.002).

CONCLUSIONS

Our current data strongly suggest that COVID-19 leaves a persistent capillary rarefication even 18 months after infection. Whether, to what extent, and when the observed damage might be reversible remains unclear.

Safety and efficacy of the Seraph® 100 Microbind® Affinity Blood Filter to remove bacteria from the blood stream: results of the first in human study

Background

Bacterial burden as well as duration of bacteremia influence the outcome of patients with bloodstream infections. Promptly decreasing bacterial load in the blood by using extracorporeal devices in addition to anti-infective therapy has recently been explored. Preclinical studies with the Seraph® 100 Microbind® Affinity Blood Filter (Seraph® 100), which consists of heparin that is covalently bound to polymer beads, have demonstrated an effective binding of bacteria and viruses. Pathogens adhere to the heparin coated polymer beads in the adsorber as they would normally do to heparan sulfate on cell surfaces. Using this biomimetic principle, the Seraph® 100 could help to decrease bacterial burden in vivo.

Methods

This first in human, prospective, multicenter, non-randomized interventional study included patients with blood culture positive bloodstream infection and the need for kidney replacement therapy as an adjunctive treatment for bloodstream infections. We performed a single four-hour hemoperfusion treatment with the Seraph® 100 in conjunction with a dialysis procedure. Post procedure follow up was 14 days.

Results

Fifteen hemodialysis patients (3F/12 M, age 74.0 [68.0–78.5] years, dialysis vintage 28.0 [11.0–45.0] months) were enrolled. Seraph® 100 treatment started 66.4 [45.7–80.6] hours after the initial positive blood culture was drawn. During the treatment with the Seraph® 100 with a median blood flow of 285 [225–300] ml/min no device or treatment related adverse events were reported. Blood pressure and heart rate remained stable while peripheral oxygen saturation improved during the treatment from 98.0 [92.5–98.0] to 99.0 [98.0–99.5] %; p = 0.0184. Four patients still had positive blood culture at the start of Seraph® 100 treatment. In one patient blood cultures turned negative during treatment. The time to positivity (TTP) was increased between inflow and outflow blood cultures by 36 [− 7.2 to 96.3] minutes. However, overall TTP increase was not statistical significant.

Conclusions

Seraph® 100 treatment was well tolerated. Adding Seraph® 100 to antibiotics early in the course of bacteremia might result in a faster resolution of bloodstream infections, which has to be evaluated in further studies.

Trail registration: ClinicalTrials.gov Identifier: NCT02914132, first posted September 26, 2016.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-022-04044-7.

Epidemiology, management, and outcome of infection, sepsis, and septic shock in a German emergency department (EpiSEP study)

BACKGROUND

The adjacent conditions infection, sepsis, and septic shock are among the most common causes of treatment in the emergency department (ED). Most available data come from intensive care units (ICU) and include nosocomial infections acquired during hospitalization. Epidemiological data from German EDs are not yet available, although the ED is one of the first points of contact for patients. The aim of this study was to investigate the epidemiology, causes, diagnosis, mortality, and treatment of patients with infections in the ED.

MATERIALS AND METHODS

In this retrospective, single-center observational study, routinely collected data from the patient data management system and from the hospital information system were analyzed. All adult patients who presented to the ED in connection with an infection during the study period from 01/01 to 28/02/2019 were included. Exclusion criteria were age ≤ 17 years and incomplete records. Three groups (I. Infection, II. Sepsis, and III. Septic shock) were defined according to SEPSIS-3 definitions.

RESULTS

During the study period, a total of 6,607 patients were treated in the ED. Of these patients, 19.3% (n = 1,278) had an infection (mean age 56 ± 23 years, 50% female). The sites of infection were distributed as follows: Respiratory tract 35%, genitourinary tract 18%, maxillofacial/ears/nose/throat 14%, intraabdominal 13%, soft tissues 10%, central nervous system 1%, other cause 3%, or unknown cause 6%. Infection only, sepsis and septic shock were present in 86, 10, and 3%, respectively. There were significant differences in vital signs as well as in the various emergency sepsis scores across the predefined groups [I vs. II vs. III: SOFA (pts.): 1 ± 1 vs. 4 ± 2 vs. 7 ± 3 (p < 0.0001), systolic blood pressure (mmHg): 137 ± 25 vs. 128 ± 32 vs. 107 ± 34 (p < 0.05), heart rate (bpm): 92 ± 18 vs. 99 ± 23 vs. 113 ± 30 (p < 0.05), respiratory rate (min-1): 18 ± 4 vs. 20 ± 7 vs. 24 ± 10 (p < 0.05)]. In the three groups, blood cultures were obtained in 34, 81, and 86%, of cases, respectively and antibiotics were administered in the ED in 50, 89, and 86%, of cases respectively. The 30-day mortality rate in the three groups was 1.6, 12.0, and 38.1%, respectively.

CONCLUSION

This study is the first to show the incidence, management, and outcome of patients classified as infection, sepsis, and septic shock in a German ED. The findings of our real-world data are important for quality management and enable the optimization of treatment pathways for patients with infectious diseases.

Lethal Waterhouse-Friderichsen syndrome caused by Capnocytophaga canimorsus in an asplenic patient

Background

Capnocytophaga canimorsus, a Gram-negative rod, belongs to the Flavobacteriaceae family and colonizes the oropharynx of dogs and cats. Infections with C. canimorsus are rare and can induce a systemic infection with a severe course of the disease. So far, only five case reports of C. canimorsus infections associated with Waterhouse–Friderichsen Syndrome (WFS) have been reported with only two of the patients having a history of splenectomy.

Case presentation

Here, we report a fatal case of WFS due to C. canimorsus bacteremia and mycetal superinfection in a 61-year-old female asplenic patient. Despite extensive therapy including mechanical ventilation, antibiotic coverage with meropenem, systemic corticosteroids medication, vasopressor therapy, continuous renal replacement therapy, therapeutic plasma exchange, multiple transfusions of blood products and implantation of a veno-arterial extracorporeal membrane oxygenation the patient died 10 days after a dog bite. The autopsy showed bilateral hemorrhagic necrosis of the adrenal cortex and septic embolism to heart, kidneys, and liver. Diagnosis of C. canimorsus was prolonged due to the fastidious growth of the bacteria.

Conclusions

The occurrence of a severe sepsis after dog bite should always urge the attending physician to consider C. canimorsus as the disease-causing pathogen. A therapeutic regimen covering C. canimorsus such as aminopenicillins or carbapenems should be chosen. However, despite maximum therapy, the prognosis of C. canimorsus-induced septic shock remains very poor. Asplenic or otherwise immunocompromised patients are at higher risk for a severe course of disease and should avoid exposure to dogs and cats and consider antibiotic prophylaxis after animal bite.

Development of the Interdisciplinary and Interprofessional Course Concept “Advanced Critical Illness Life Support”

The Advanced Critical Illness Life Support (ACiLS) course was developed on behalf of the German Society for Interdisciplinary Emergency and Acute Medicine (DGINA). The goal of the ACiLS course is to provide a nationally recognized and certified life support course that teaches medical professionals the key principles of initial care of critically ill patients in the emergency department, including the (PR_E-)AUD2IT-algorithm. It is designed for interdisciplinary and multi-professional staff in the resuscitation room to optimize patient safety and outcome. ACiLS includes a new blended learning concept with a theoretical part as comprehensive e-learning and a two-day practical part with strong focus on team training in scenarios and workshops. The course format was conceived to balance best teaching practices within the limited instructional time and resources available. This article describes the development of the ACiLS course and provides an overview of its future implementation.

[Management of Critically Ill Non-traumatic Patients in the Emergency Department]

Resuscitation room management of non-traumatic critically ill patients in the emergency department comprises approximately 1.5% of all emergency department visits. Critically ill patients are usually brought to the hospital by emergency medical services, where they are first examined, given initial treatment, stabilized and then transported for further in-hospital treatment. Resuscitation room management plays a key role at the interface of the out-of-hospital and in-hospital treatment chains. While the structured care of traumatological patients has been established at a very high level for decades, the care of non-traumatic critically ill patients within the framework of resuscitation room care has only come into focus in recent years and is only now being implemented in some places with professional concepts. Emergency departments at all levels of care are equipped to provide structured care for non-traumatologic shock room patients. To professionalize non-traumatic resuscitation room management, the creation of uniform standards from alerting criteria, to equipment and staffing, as well as the establishment of a uniform resuscitation room management algorithm is required. The (PRE_E-)AUD2IT-algorithm provides a structure for the non-traumatic care of critically ill patients in the resuscitation room and includes preparation, resource retrieval, handover, initial care, diagnostics, differential diagnoses and the interpretation of examination findings. This overview focuses on the management of critically ill non-traumatic patients in respect to the resuscitation room care concept.

Heparanase Is a Putative Mediator of Endothelial Glycocalyx Damage in COVID-19 - A Proof-of-Concept Study

Coronavirus disease 2019 (COVID-19) is a systemic disease associated with injury (thinning) of the endothelial glycocalyx (eGC), a protective layer on the vascular endothelium. The aim of this translational study was to investigate the role of the eGC-degrading enzyme heparanase (HPSE), which is known to play a central role in the destruction of the eGC in bacterial sepsis. Excess activity of HPSE in plasma from COVID-19 patients correlated with several markers of eGC damage and perfused boundary region (PBR, an inverse estimate of glycocalyx dimensions of vessels with a diameter 4-25 µm). In a series of translational experiments, we demonstrate that the changes in eGC thickness of cultured cells exposed to COVID-19 serum correlated closely with HPSE activity in concordant plasma samples (R = 0.82, P = 0.003). Inhibition of HPSE by a nonanticoagulant heparin fragment prevented eGC injury in response to COVID-19 serum, as shown by atomic force microscopy and immunofluorescence imaging. Our results suggest that the protective effect of heparin in COVID-19 may be due to an eGC-protective off-target effect.

Microvascular and proteomic signatures overlap in COVID-19 and bacterial sepsis: the MICROCODE study

AIMS

Although coronavirus disease 2019 (COVID-19) and bacterial sepsis are distinct conditions, both are known to trigger endothelial dysfunction with corresponding microcirculatory impairment. The purpose of this study was to compare microvascular injury patterns and proteomic signatures in COVID-19 and bacterial sepsis patients.

METHODS AND RESULTS

This multi-center, observational study included 22 hospitalized adult COVID-19 patients, 43 hospitalized bacterial sepsis patients, and 10 healthy controls from 4 hospitals. Microcirculation and glycocalyx dimensions were quantified via intravital sublingual microscopy. Plasma proteins were measured using targeted proteomics (Olink). Coregulation and cluster analysis of plasma proteins was performed using a training-set and confirmed in a test-set. An independent external cohort of 219 COVID-19 patients was used for validation and outcome analysis. Microcirculation and plasma proteome analysis found substantial overlap between COVID-19 and bacterial sepsis. Severity, but not disease entity explained most data variation. Unsupervised correlation analysis identified two main coregulated plasma protein signatures in both diseases that strictly counteract each other. They were associated with microvascular dysfunction and several established markers of clinical severity. The signatures were used to derive new composite biomarkers of microvascular injury that allow to predict 28-day mortality or/and intubation (area under the curve 0.90, p < 0.0001) in COVID-19.

CONCLUSION

Our data imply a common biological host response of microvascular injury in both bacterial sepsis and COVID-19. A distinct plasma signature correlates with endothelial health and improved outcomes, while a counteracting response is associated with glycocalyx breakdown and high mortality. Microvascular health biomarkers are powerful predictors of clinical outcomes.

["B problems" in non-traumatic resuscitation room management]

In the primary survey of resuscitation room management in critically ill nontrauma patients, the ABCDE (airway, breathing, circulation, disability, exposure) approach is used for immediate recognition and treatment of life-threatening conditions. "B problems" are associated with respiratory failure and require immediate treatment. The pathogenesis is diverse, especially in the nontrauma resuscitation room. Clinical examination, emergency sonography and knowledge of oxygenation techniques and ventilation are important components of diagnosis and therapy. Standardized procedures and regular training in the emergency room are of fundamental importance.

Aktuelle Ist-Analyse zur Situation des nichttraumatologischen Schockraummanagements in Deutschland

Einleitung

In Notaufnahmen kommen bundesweit nichttraumatologische kritisch kranke Patienten zur Aufnahme. Zur Struktur, Organisation und Ausstattung des nichttraumatologischen Schockraummanagements ist bisher wenig bekannt. Mittels einer Umfrage sollte daher der Ist-Zustand analysiert werden.

Methodik

Durch die Arbeitsgruppe „Schockraum“ der Deutschen Gesellschaft Interdisziplinäre Notfall- und Akutmedizin (DGINA) wurde mittels E‑Mail den 420 ärztlichen Leiter*Innen des DGINA-Mitgliederregisters eine Onlineumfrage zugesendet. Zwei Wochen nach initialem Anschreiben erfolgte eine Erinnerung. Die Ergebnisse wurden in einer anonymisierten Datenbank extrahiert und ausgewertet.

Ergebnisse

Insgesamt lag die Rücklaufquote mit 131 verwertbaren Antworten bei 31 %. Die Umfrage erfasste Krankenhäuser der Basis- (24 %), erweiterten (39 %) und umfassenden Notfallversorgung (37 %). Korrespondierend zur Versorgungsstufe stiegen die jährlichen Patientenkontakte (21.000 vs. 31.000 vs. 39.000), die Monitorplätze in den Notaufnahmen (9 ± 4 vs. 13 ± 6 vs. 18 ± 10), die Betten der assoziierten Notaufnahmestationen (4 ± 5 vs. 10 ± 17 vs. 13 ± 12), die verfügbaren Schockräume (1 ± 1 vs. 2 ± 1 vs. 3 ± 1) und deren Größe (31 ± 16 vs. 35 ± 9 vs. 38 ± 14 m2) an. Hinsichtlich verschiedener Ausstattungsmerkmale (z. B. Röntgenlafette: 58 vs. 65 vs. 78 %, Computertomographie im Schockraum: 6 vs. 12 vs. 27 %) zeigten sich deutliche Unterschiede in Abhängigkeit von der Versorgungsstufe. Während Kühlungssysteme in 30 % in allen Versorgungsstufen vorgehalten wurden, fanden sich andere Ausstattungsmerkmale (z. B. Videolaryngoskopie: 65 vs. 80 vs. 86 %, Bronchoskopie: 29 vs. 22 vs. 45 %) und spezielle Notfallprozeduren (z. B. REBOA [„resuscitative endovascular balloon occlusion of the aorta“]: 3 vs. 5 vs. 12 %, ACCD [„automated chest compression device“]: 26 vs. 57 vs. 61 %) häufiger in höheren Versorgungsstufen.

Schlussfolgerung

Die vorliegenden Ergebnisse zeigen erstmals den Ist-Zustand der nichttraumatologischen Schockraumversorgung in verschiedenen Versorgungsstufen in Deutschland. Empfehlungen zu Ausstattungsmerkmalen für das nichttraumatologische Schockraummanagement müssen zukünftig formuliert werden.

[Epidemiology and Causes of Acute Renal Failure and Transition to Chronic Kidney Disease]

Acute kidney injury (AKI) refers to an acute functional deterioration of the kidneys, which leads to retention of urinary substances, dysregulation of the electrolyte and acid-base balance, and disturbance of fluids. Although didactically helpful, the oversimplified AKI classification of prerenal/renal/postrenal is currently considered obsolete. Indeed, the boundaries blur quite quickly, particularly between prerenal and renal causes. Based on the AKI pathophysiology, it can be etiologically divided into decreased renal perfusion, postrenal obstruction and kidney specific injury or unspecific injury. AKI is a common event in hospitalized patients and associates strongly with mortality and chronic kidney disease (CKD). Today it is accepted that AKI and CKD are rather an individually variable continuum, than 2 distinct entities. If AKI has not regressed after 7 days, it is referred to as acute kidney disease (AKD). Persisting AKD for > 90 days is classified as CKD. The transition from AKD to CKD is the result of an incomplete and maladaptive repair process. Although follow-up of post-AKI patients is essential, optimal concepts still need to be developed.

Targeting the "sweet spot" in septic shock - A perspective on the endothelial glycocalyx regulating proteins Heparanase-1 and -2

Sepsis is a life-threatening syndrome caused by a pathological host response to an infection that eventually, if uncontrolled, leads to septic shock and ultimately, death. In sepsis, a massive aggregation of pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs) cause a cytokine storm. The endothelial glycocalyx (eGC) is a gel like layer on the luminal side of the endothelium that consists of proteoglycans, glycosaminoglycans (GAG) and plasma proteins. It is synthesized by endothelial cells and plays an active role in the regulation of inflammation, permeability, and coagulation. In sepsis, early and profound injury of the eGC is observed and circulating eGC components correlate directly with clinical severity and outcome. The activity of the heparan sulfate (HS) specific glucuronidase Heparanase-1 (Hpa-1) is elevated in sepsis, resulting in shedding of heparan sulfate (HS), a main GAG of the eGC. HS induces endothelial barrier breakdown and accelerates systemic inflammation. Lipopolysaccharide (LPS), a PAMP mainly found on the surface of gram-negative bacteria, activates TLR-4, which results in cytokine production and further activation of Hpa-1. Hpa-1 shed HS fragments act as DAMPs themselves, leading to a vicious cycle of inflammation and end-organ dysfunction such as septic cardiomyopathy and encephalopathy. Recently, Hpa-1's natural antagonist, Heparanase-2 (Hpa-2) has been identified. It has no intrinsic enzymatic activity but instead acts by reducing inflammation. Hpa-2 levels are reduced in septic mice and patients, leading to an acquired imbalance of Hpa-1 and Hpa-2 paving the road towards a therapeutic intervention. Recently, the synthetic antimicrobial peptide 19-2.5 was described as a promising therapy protecting the eGC by inhibition of Hpa-1 activity and HS shed fragments in animal studies. However, a recombinant Hpa-2 therapy does not exist to the present time. Therapeutic plasma exchange (TPE), a modality already tested in clinical practice, effectively removes injurious mediators, e.g., Hpa-1, while replacing depleted protective molecules, e.g., Hpa-2. In critically ill patients with septic shock, TPE restores the physiological Hpa-1/Hpa-2 ratio and attenuates eGC breakdown. TPE results in a significant improvement in hemodynamic instability including reduced vasopressor requirement. Although promising, further studies are needed to determine the therapeutic impact of TPE in septic shock.

Protection and rebuilding of the endothelial glycocalyx in sepsis - Science or fiction?

The endothelial glycocalyx (eGC), a delicate carbohydrate-rich structure lining the luminal surface of the vascular endothelium, is vital for maintenance of microvascular homeostasis. In sepsis, damage of the eGC triggers the development of vascular hyperpermeability with consecutive edema formation and organ failure. While there is evidence that protection or rebuilding of the eGC might counteract sepsis-induced vascular leakage and improve outcome, approved therapeutics are not yet available. This narrative review aims to outline possible therapeutic strategies to ameliorate organ dysfunction caused by eGC impairment.

Identification and validation of objective triggers for initiation of resuscitation management of acutely ill non-trauma patients: the INITIATE IRON MAN study

Background

While there are clear national resuscitation room admission guidelines for major trauma patients, there are no comparable alarm criteria for critically ill nontrauma (CINT) patients in the emergency department (ED). The aim of this study was to define and validate specific trigger factor cut-offs for identification of CINT patients in need of a structured resuscitation management protocol.

Methods

All CINT patients at a German university hospital ED for whom structured resuscitation management would have been deemed desirable were prospectively enrolled over a 6-week period (derivation cohort, n = 108). The performance of different thresholds and/or combinations of trigger factors immediately available during triage were compared with the National Early Warning Score (NEWS) and Quick Sequential Organ Failure Assessment (qSOFA) score. Identified combinations were then tested in a retrospective sample of consecutive nontrauma patients presenting at the ED during a 4-week period (n = 996), and two large external datasets of CINT patients treated in two German university hospital EDs (validation cohorts 1 [n = 357] and 2 [n = 187]).

Results

The any-of-the-following trigger factor iteration with the best performance in the derivation cohort included: systolic blood pressure < 90 mmHg, oxygen saturation < 90%, and Glasgow Coma Scale score < 15 points. This set of triggers identified > 80% of patients in the derivation cohort and performed better than NEWS and qSOFA scores in the internal validation cohort (sensitivity = 98.5%, specificity = 98.6%). When applied to the external validation cohorts, need for advanced resuscitation measures and hospital mortality (6.7 vs. 28.6%, p < 0.0001 and 2.7 vs. 20.0%, p < 0.012) were significantly lower in trigger factor-negative patients.

Conclusion

Our simple, any-of-the-following decision rule can serve as an objective trigger for initiating resuscitation room management of CINT patients in the ED.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13049-021-00973-4.

[University emergency departments in the corona pandemic-Results from the ReCovER registry]

Hintergrund

Die aktuelle COVID-19-Pandemie stellt, trotz der Verfügbarkeit von Schnelltests und des Starts der Impfkampagne, die Notaufnahme weiterhin vor große Herausforderungen. Die strukturierte Erfassung von demographischen, klinischen sowie therapiebezogenen Daten stellt die Grundlage für die Erstellung evidenzbasierter Prozesse und Behandlungskonzepte dar.

Ziel der Arbeit

Darstellung der systematischen Erfassung klinischer Parameter bei Patienten mit COVID-19-Verdacht im Notaufnahmeregister ReCovER (Registry for COVID-19 in the Emergency Room) sowie deskriptive Darstellung der ersten 1000 Patienten.

Material und Methoden

In zentralen Notaufnahmen (ZNA) von 6 Universitätskliniken werden kontinuierlich Daten von Patienten mit COVID-19-Verdacht, unabhängig vom Nachweis einer SARS-CoV-2-Infektion, in ein webbasiertes, anonymisiertes Register eingegeben.

Ergebnisse

Zwischen dem 19.05.2020 und dem 13.01.2021 wurden 1000 Patienten in das Register eingegeben, hiervon waren 594 Patienten (59,4 %) in der SARS-CoV-2-positiven (PG) und 406 Patienten (40,6 %) in der negativen Gruppe (NG). Patienten der PG hatten signifikant weniger Vorerkrankungen und eine deutlich längere Latenz zwischen Symptombeginn und Vorstellung in der ZNA (Median 5 vs. 3 Tage), litten häufiger unter Husten, Myalgien, Fatigue sowie Geruchs/Geschmacksverlust und hatten einen signifikant höheren Sauerstoffbedarf als die NG-Patienten. Die Rate von schweren Krankheitsverläufen war in der PG signifikant erhöht und es bestanden nach Entlassung häufiger persistierende Symptome (11,1 vs. 4,6 %).

Schlussfolgerungen

Durch die multizentrische Erfassung von umfangreichen klinischen Daten zu COVID-19-Verdachtsfällen in der Notaufnahme können insbesondere auch für die Situation in Deutschland spezifische Aspekte analysiert werden. Dies ist essenziell für eine gezielte Überprüfung und Adaption international publizierter Strategien.

Role of angiopoietin-2 in venous thrombus resolution and chronic thromboembolic disease

Defective angiogenesis, incomplete thrombus revascularisation and fibrosis are considered critical pathomechanisms of chronic thromboembolic pulmonary hypertension (CTEPH) after pulmonary embolism (PE). Angiopoietin-2 (ANGPT2) has been shown to regulate angiogenesis, but its importance for thrombus resolution and remodelling is unknown.ANGPT2 plasma concentrations were measured in patients with CTEPH (n=68) and acute PE (n=84). Tissue removed during pulmonary endarterectomy (PEA) for CTEPH was analysed (immuno)histologically. A mouse model of inferior vena cava ligation was used to study the kinetics of venous thrombus resolution in wild-type mice receiving recombinant ANGPT2 via osmotic pumps, and in transgenic mice overexpressing ANGPT2 in endothelial cells.Circulating ANGPT2 levels were higher in CTEPH patients compared to patients with idiopathic pulmonary arterial hypertension and healthy controls, and decreased after PEA. Plasma ANGPT2 levels were also elevated in patients with PE and diagnosis of CTEPH during follow-up. Histological analysis of PEA specimens confirmed increased ANGPT2 expression, and low levels of phosphorylated TIE2 were observed in regions with early-organised pulmonary thrombi, myofibroblasts and fibrosis. Microarray and high-resolution microscopy analysis could localise ANGPT2 overexpression to endothelial cells, and hypoxia and TGF-β1 were identified as potential stimuli. Gain-of-function experiments in mice demonstrated that exogenous ANGPT2 administration and transgenic endothelial ANGPT2 overexpression resulted in delayed venous thrombus resolution, and thrombi were characterised by lower TIE2 phosphorylation and fewer microvessels.Our findings suggest that ANGPT2 delays venous thrombus resolution and that overexpression of ANGPT2 contributes to thrombofibrosis and may thus support the transition from PE to CTEPH.

Which parameters support disposition decision in suspected COVID-19 cases in the emergency department (ED): a German clinical cohort study

OBJECTIVES

One major goal of the emergency department (ED) is to decide, whether patients need to be hospitalised or can be sent home safely. We aim at providing criteria for these decisions without knowing the SARS-CoV-2 test result in suspected cases.

SETTING

Tertiary emergency medicine.

PARTICIPANTS

All patients were treated at the ED of the Charité during the pandemic peak and underwent SARS-CoV-2 testing. Patients with positive test results were characterised in detail and underwent a 14-day-follow-up.

PRIMARY AND SECONDARY OUTCOME MEASURES

Logistic regression and classification and regression tree (CART) analyses were performed to identify predictors (primary endpoint), which confirm safe discharge. The clinical endpoint was all-cause mortality or need for mechanical ventilation during index stay or after readmission.

RESULTS

The primary test population of suspected COVID-19 consisted of n=1255 cases, 45.2% were women (n=567). Of these, n=110 tested positive for SARS-CoV-2 (8.8%). The median age of SARS-CoV-2-positive cases was 45 years (IQR: 33-66 years), whereas the median age of the group tested negative for SARS-CoV-2 was 42 years (IQR: 30-60 years) (p=0.096). 43.6% were directly admitted to hospital care.CART analysis identified the variables oxygen saturation (<95%), dyspnoea and history of cardiovascular (CV) disease to distinguish between high and low-risk groups. If all three variables were negative, most patients were discharged from ED, and the incidence of the clinical endpoint was 0%. The validation cohort confirmed the safety of discharge using these variables and revealed an incidence of the clinical endpoint from 14.3% in patients with CV disease, 9.4% in patients with dyspnoea and 18.2% in patients with O₂ satuaration below 95%.

CONCLUSIONS

Based on easily available variables like dyspnoea, oxygen saturation, history of CV disease, approximately 25% of patients subsequently confirmed with COVID-19 can be identified for safe discharge.

TRIAL REGISTRATION NUMBER

DRKS00023117.

Identification of novel sublingual parameters to analyze and diagnose microvascular dysfunction in sepsis: the NOSTRADAMUS study

Background

The availability of handheld, noninvasive sublingual video-microscopes allows for visualization of the microcirculation in critically ill patients. Recent studies demonstrate that reduced numbers of blood-perfused microvessels and increased penetration of erythrocytes into the endothelial glycocalyx are essential components of microvascular dysfunction. The aim of this study was to identify novel microvascular variables to determine the level of microvascular dysfunction in sepsis and its relationship with clinical variables.

Methods

This observational, prospective, cross-sectional study included 51 participants, of which 34 critically ill sepsis patients were recruited from intensive care units of a university hospital. Seventeen healthy volunteers served as controls. All participants underwent sublingual videomicroscopy by sidestream darkfield imaging. A new developed version of the Glycocheck™ software was used to quantify vascular density, perfused boundary region (PBR-an inverse variable of endothelial glycocalyx dimensions), red blood cell (RBC) velocity, RBC content, and blood flow in sublingual microvessels with diameters between 4 and 25 µm.

Results

A detailed analysis of adjacent diameter classes (1 µm each) of vessels between 4 and 25 µm revealed a severe reduction of vascular density in very small capillaries (5–7 µm), which correlated with markers of sepsis severity. Analysis of RBC velocity (V_RBC) revealed a strong dependency between capillary and feed vessel V_RBC in sepsis patients (R² = 0.63, p < 0.0001) but not in healthy controls (R² = 0.04, p = 0.43), indicating impaired capillary (de-)recruitment in sepsis. This finding enabled the calculation of capillary recruitment and dynamic capillary blood volume (CBV_dynamic). Moreover, adjustment of PBR to feed vessel V_RBC further improved discrimination between sepsis patients and controls by about 50%. By combining these dynamic microvascular and glycocalyx variables, we developed the microvascular health score (MVHS_dynamic™), which decreased from 7.4 [4.6–8.7] in controls to 1.8 [1.4–2.7] in sepsis patients (p < 0.0001) and correlated with sepsis severity.

Conclusion

We introduce new important diameter-specific quantification and differentiated analysis of RBC kinetics, a key to understand microvascular dysfunction in sepsis. MVHS_dynamic, which has a broad bandwidth to detect microvascular (dys-) function, might serve as a valuable tool to detect microvascular impairment in critically ill patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-021-03520-w.

[Isolation precautions, diagnostics and organization in German emergency departments during the 2020 COVID-19 pandemic]

BACKGROUND

Since the beginning of the coronavirus disease 19 (COVID-19) pandemic, German emergency departments (ED) have been working in the area of conflict between high case load and demanding hygienic and organizational challenges. The aim of this study was to gain an overview of the current status of isolation measures, diagnostics and patient allocation of suspected COVID-19 cases.

METHODS

Supported by the German Society for Interdisciplinary Emergency and Acute Medicine (DGINA) we invited leading ED physicians to answer an anonymous online survey regarding isolation measures, diagnostics and organization in emergency rooms during the COVID-19 pandemic.

RESULTS

A total of 139 responders from all federal states and all levels of care took part in the survey. Standard operating procedures on COVID-19 exist in almost all participating EDs, although concrete measures to end isolation are often missing. Most EDs screen patients for the "classic" COVID-19 symptoms such as fever, respiratory symptoms or contact to positive subjects in a standardized fashion, although the threshold for prophylactic isolation varies greatly. The individual swab-testing and allocation strategies vary relatively strongly. Less than half of all EDs have a separate procedure for uninterrogatable patients (e.g. major trauma). In about 8% of suspected cases, COVID-19-specific thoracic computed tomography is performed in the ED.

CONCLUSION

The current survey shows that the German EDs are well positioned for the moment, even though the isolation threshold is too high at some locations. In view of a possible increase in the number of cases during the winter season, a more precise differentiation of the previous recommendations of the Robert Koch Institute, especially for emergency admission patients, would be desirable. In this context, we propose a universal algorithm for the (de-)isolation of suspect cases in the ED.

Microvascular dysfunction in COVID-19: the MYSTIC study

RATIONALE

Pre-clinical and autopsy studies have fueled the hypothesis that a dysregulated vascular endothelium might play a central role in the pathogenesis of ARDS and multi-organ failure in COVID-19.

OBJECTIVES

To comprehensively characterize and quantify microvascular alterations in patients with COVID-19.

METHODS

Hospitalized adult patients with moderate-to-severe or critical COVID-19 (n = 23) were enrolled non-consecutively in this prospective, observational, cross-sectional, multi-center study. Fifteen healthy volunteers served as controls. All participants underwent intravital microscopy by sidestream dark field imaging to quantify vascular density, red blood cell velocity (V_RBC), and glycocalyx dimensions (perfused boundary region, PBR) in sublingual microvessels. Circulating levels of endothelial and glycocalyx-associated markers were measured by multiplex proximity extension assay and enzyme-linked immunosorbent assay.

MEASUREMENTS AND MAIN RESULTS

COVID-19 patients showed an up to 90% reduction in vascular density, almost exclusively limited to small capillaries (diameter 4-6 µm), and also significant reductions of V_RBC. Especially, patients on mechanical ventilation showed severe glycocalyx damage as indicated by higher PBR values (i.e., thinner glycocalyx) and increased blood levels of shed glycocalyx constituents. Several markers of endothelial dysfunction were increased and correlated with disease severity in COVID-19. PBR (AUC 0.75, p = 0.01), ADAMTS13 (von Willebrand factor-cleaving protease; AUC 0.74, p = 0.02), and vascular endothelial growth factor A (VEGF-A; AUC 0.73, p = 0.04) showed the best discriminatory ability to predict 60-day in-hospital mortality.

CONCLUSIONS

Our data clearly show severe alterations of the microcirculation and the endothelial glycocalyx in patients with COVID-19. Future therapeutic approaches should consider the importance of systemic vascular involvement in COVID-19.

[The hypertensive emergency situation : Recommendations for initial drug therapy management]

The hypertensive emergency situation is characterized by an acute-mostly life-threatening-blood pressure derailment with the risk of acute end organ damage. It is an acute manifestation of arterial hypertension, which manifests in a variety of symptoms. The etiology is in most cases long-term (chronic) hypertension as a result of low compliance or inadequate antihypertensive therapy. It can also occur as a first manifestation of arterial hypertension. It requires timely antihypertensive drug therapy, which should be initiated in an intensive or intermediate care unit. The choice of antihypertensive therapy regimen should be based on the underlying end organ damage. Fast-acting, easily controllable and intravenously administered substances should be preferred. The most commonly used substances (groups) are urapidil, nitroglycerin, beta blockers and short-acting calcium channel blockers. With a few exceptions, a deliberate, rapid reduction in blood pressure of no more than 20-25% of the initial value is sufficient for extracerebral causes. A subsequent systolic blood pressure target of 160/100 mm Hg should be aimed for within the next 2-6 h. An overly rapid drop in blood pressure can lead to reduced blood flow to the central nervous system due to changes in autoregulation. Exceptions to this rule are acute aortic dissection and flash pulmonary edema-in these cases, prompt blood pressure normalization should be achieved. The initial acute therapy should be followed by a more detailed investigation of the cause and a long-term therapy setting based on this.

Symmetric dimethylarginine in dysfunctional high-density lipoprotein mediates endothelial glycocalyx breakdown in chronic kidney disease

Dysfunctional high-density lipoprotein (d-HDL) in chronic kidney disease is known to have a change in composition towards an endothelial-damaging phenotype, amongst others, via the accumulation of symmetric dimethylarginine. The endothelial glycocalyx, a carbohydrate-rich layer lining the endothelial luminal surface, is a first line defense against vascular diseases including atherosclerosis. Here we conducted a translational, cross-sectional study to determine the role of symmetric dimethylarginine in d-HDL as a mediator of glycocalyx damage. Using confocal and atomic force microscopy, intact HDL from healthy donors was found to maintain the glycocalyx while isolated HDL from hemodialysis patients and exogenous symmetric dimethylarginine caused significant damage to the glycocalyx in endothelial cells in vitro in a dose-dependent manner. Symmetric dimethylarginine triggered glycocalyx deterioration via molecular pathways mediated by toll-like-receptor 2 and matrix metalloprotease-9. Corresponding intravital microscopy revealed that exogenous symmetric dimethylarginine and d-HDL from hemodialysis patients caused glycocalyx breakdown, which subsequently contributed to alterations in leukocyte rolling. Biologically effective HDL, which estimates the functionality of HDL, was calculated from circulating HDL-cholesterol and symmetric dimethylarginine, as described in the literature. Biologically effective HDL was the only parameter that could independently predict glycocalyx damage in vivo. Thus, our data suggest that symmetric dimethylarginine in d-HDL mediates glycocalyx breakdown in chronic kidney disease.

Tie2 Activation Promotes Protection and Reconstitution of the Endothelial Glycocalyx in Human Sepsis

The endothelial glycocalyx (eGC), a carbohydrate-rich layer lining the luminal surface of the endothelium, provides a first vasoprotective barrier against vascular leakage in sepsis. We hypothesized that angiopoietin-2 (Angpt-2), antagonist of the endothelium-stabilizing receptor Tie2, induces a rapid loss of the eGC in human sepsis. Using intravital microscopy, we measured the perfused boundary region (PBR), an inverse parameter of eGC dimensions in sublingual microvessels, in patients with sepsis and age-matched nonseptic subjects. Median PBR values were significantly higher in patients compared with controls and correlated with serum Angpt-2 levels. To transfer and further explore these findings in a cell culture system, we exposed endothelial cells (ECs) to serum (5%) from a subgroup of septic patients and nonseptic controls. Confocal and atomic force microscopy revealed that sepsis serum, but not control serum, induced thinning of the eGC on human ECs in vitro, which correlated with paired PBR values obtained in vivo (r = 0.96, p < 0.01). Inhibition of Angpt-2 or Tie2 activation completely abolished eGC damage. Mechanistically, sepsis-induced eGC breakdown required the loss of its main constituent heparan sulfate; a result of heparan sulfate-specific enzyme heparanase, which was suppressed by Tie2 activation. Finally, Tie2 activation, but not Angpt-2 inhibition, initiated after septic or enzymatic damage provoked rapid refurbishment of the eGC. Our data indicate that eGC breakdown in human sepsis is mediated via Tie2 deactivation by Angpt-2. Activation of Tie2 seems to accelerate recovery of the eGC and might hold promise as a therapeutic target in human sepsis.

Association of sublingual microcirculation parameters and endothelial glycocalyx dimensions in resuscitated sepsis

Background

The endothelial glycocalyx (eGC) covers the luminal surface of the vascular endothelium and plays an important protective role in systemic inflammatory states and particularly in sepsis. Its breakdown leads to capillary leak and organ dysfunction. Moreover, sepsis-induced alterations of sublingual microcirculation are associated with a worse clinical outcome. The present study was performed to investigate the associations between eGC dimensions and established parameters of microcirculation dysfunction in sepsis.

Methods

This observational, prospective, cross-sectional study included 40 participants, of which 30 critically ill septic patients were recruited from intensive care units of a university hospital and 10 healthy volunteers served as controls. The established microcirculation parameters were obtained sublingually and analyzed according to the current recommendations. In addition, the perfused boundary region (PBR), an inverse parameter of the eGC dimensions, was measured sublingually, using novel data acquisition and analysis software (GlycoCheck™). Moreover, we exposed living endothelial cells to 5% serum from a subgroup of study participants, and the delta eGC breakdown, measured with atomic force microscopy (AFM), was correlated with the paired PBR values.

Results

In septic patients, sublingual microcirculation was impaired, as indicated by a reduced microvascular flow index (MFI) and a reduced proportion of perfused vessels (PPV) compared to those in healthy controls (MFI, 2.93 vs 2.74, p = 0.002; PPV, 98.53 vs 92.58, p = 0.0004). PBR values were significantly higher in septic patients compared to those in healthy controls, indicating damage of the eGC (2.04 vs 2.34, p < 0.0001). The in vitro AFM data correlated exceptionally well with paired PBR values obtained at the bedside (rs = − 0.94, p = 0.02). Both PBR values and microcirculation parameters correlated well with the markers of critical illness. Interestingly, no association was observed between the PBR values and established microcirculation parameters.

Conclusion

Our findings suggest that eGC damage can occur independently of microcirculatory impairment as measured by classical consensus parameters. Further studies in critically ill patients are needed to unravel the relationship of glycocalyx damage and microvascular impairment, as well as their prognostic and therapeutic importance in sepsis.

Trial registration

Retrospectively registered: Clinicaltrials.gov, NCT03960307

Electronic supplementary material

The online version of this article (10.1186/s13054-019-2542-2) contains supplementary material, which is available to authorized users.

Outcomes of renal dysfunction in patients with acute liver failure

Background

Although acute kidney injury (AKI) often accompanies acute liver failure (ALF), its impact on long-term outcome is unknown.

Objective

This study examines the incidence, severity and outcomes of AKI in patients with ALF.

Methods

A total of 134 ALF patients treated at Hannover Medical School between 1995 and 2013 were retrospectively analyzed.

Results

Fifty-four ALF patients (40.3%) demonstrated AKI, as defined by the acute kidney injury network (AKIN) classification, on intensive care unit (ICU) admission, and 85 patients (63.4%) developed AKI prior to ALF recovery, emergency liver transplantation (ELT) or death. AKI severity was closely associated with other end-organ damage (p < 0.001). Follow-up creatinine levels in survivors were increased compared to baseline levels (76 versus 64 µmol/l, p = 0.003). One-hundred-and-three (76.9%) patients reached the combined endpoint of ELT or death, and 42 (31.3%) patients died within 28 days. AKIN stage 3 at ICU admission was the strongest independent predictor of 28-day overall mortality (hazard ratio 3.48, 95% confidence interval 1.75-6.93, p < 0.001) and ELT or death (hazard ratio 2.52, 95% confidence interval 1.60-3.96, p < 0.001).

Conclusions

AKI is a frequent complication in ALF that correlates with remote organ damage and long-term creatinine levels and independently predicts outcome.

A Novel PKD1 Mutation Associated With Autosomal Dominant Kidney Disease and Cerebral Cavernous Malformation

Autosomal dominant polycystic kidney disease (ADPKD) is a genetic disorder characterized by the presence of renal cysts and specific extrarenal abnormalities. ADPKD is caused by mutations in either PKD1 or PKD2 genes that encode for integral membrane proteins Polycystin-1 (PC1) and Polycystin-2 (PC2), respectively. Extrarenal involvement includes noncystic manifestations such as dilatation of the aortic root, artery dissection and intracranial aneurysms. Cerebral cavernous malformation (CCM) is a rare vascular malformation disorder characterized by closely clustered and irregularly dilated capillaries that can be asymptomatic or cause variable neurological manifestations, such as seizures, non-specific headaches, progressive or transient focal neurologic deficits, and cerebral hemorrhages. Familial CCM is typically associated with mutations in KRIT1 (CCM1), CCM2, and PDCD10 (CCM3). The co-occurrence of ADPKD and CCM has been previously described in a single patient, although genetic analysis was not performed in this study. We report here a family with ADPKD associated with CCM in two sisters. Direct sequencing of the index patient revealed a single novel heterozygous frameshift mutation in PKD1, and lack of mutations in genes usually related to CCM. This suggests that CCM represents an additional phenotype of ADPKD.

Endothelial dysfunction following coronary artery bypass grafting : Influence of patient and procedural factors

BACKGROUND

Angiopoietin-2 (Angpt2) mediates endothelial dysfunction (ED) following coronary artery bypass grafting (CABG). Its triggers are, however, poorly understood.

METHODS

We examined the time course of ED beyond the early phase of postoperative recovery in 75 patients following CABG with a special focus on different cardiopulmonary bypass (CPB) modes as potential triggers of Angpt2 release.

RESULTS

Nine patients (12.0%) underwent off-pump coronary artery bypass (OPCAB), 31 patients (41.3%) received minimized extracorporeal circulation (MECC), and 35 patients (46.6%) were operated on with (conventional) CPB. Angpt2 levels steadily increased across the observation period (1.7 [1.4-2.1] to 3.4 [2.5-6.1] ng/ml, p < 0.001). Angpt2 levels did not differ between the MECC and CPB groups (p = 0.564). There was no difference between MECC and CPB patients regarding net fluid balance (p = 0.821) and other surrogate markers of postoperative ED. The magnitude of Angpt-2 increase correlated more strongly with baseline C‑reactive protein (r = 0.459, p < 0.001) than with any other parameter. Hospital length of stay correlated more strongly with baseline Angpt2 levels (r = 0.512, p = 0.005) than with follow-up Angpt2 levels and appeared not to be influenced by CPB mode (p = 0.428).

CONCLUSION

CABG is associated with prolonged ED, which is determined by the patient's preoperative inflammatory state rather than by CPB modifications.

The curse of angiopoietin-2 in ARDS: on stranger TI(E)des

Pulmonary inflammation and vascular leakage are hallmarks of acute respiratory distress syndrome (ARDS), a life-threatening condition, for which there is no specific pharmacologic treatment.

Recent literature suggests that leaky vessels in pulmonary infection and ARDS may be mediated through dysregulation of a non-redundant endothelial control pathway, the Tie2 receptor and its ligands, the angiopoietins.

This Viewpoint summarizes results from cell-based experiments, animal models and clinical studies underlining the potential of Tie2 targeted interventions in reducing infection-mediated pulmonary hyperpermeability.

Fieber und pulmo-renales Syndrom mit akuter Cholezystitis nach Südostasienreise – eine differenzialdiagnostische Herausforderung

Anamnese Wir berichten über einen 37-jährigen männlichen Patienten, der sich im Winter aufgrund von Fieber, Abgeschlagenheit sowie Kopf- und Gliederschmerzen in der Notaufnahme unserer Klinik vorstellte. Der Patient war 14 Tage zuvor aus einem Urlaub in Thailand zurückgekehrt.

Untersuchungen In klinischer Untersuchung, Laborbefunden, sowie apparativer Diagnostik zeigte sich bei diesem Patienten ein pulmo-renales Syndrom mit Multiorganbeteiligung.

Diagnose Letztendlich konnte eine Leptospirose als Ursache bestätigt werden.

Therapie Es wurde eine Penicillintherapie durchgeführt.

Verlauf Kurz nach Aufnahme musste der Patient aufgrund der Sepsis mit Multiorganaffektion auf die Intensivstation übernommen werden. Unter antibiotischer Therapie, nichtinvasiver Beatmung und mehrmaliger Hämodialyse konnte der Zustand des Patienten stabilisiert werden. Nach knapp vierwöchigem Krankenhausaufenthalt konnte er in gutem Allgemeinzustand nach Hause entlassen werden.

Folgerung Vor Hintergrund der jahreszeitlichen Häufung grippaler Symptome im Winter sowie der Tropenrückkehrer-Anamnese stellte dieser Fall eine differenzialdiagnostische Herausforderung dar. Die Leptospirose ist eine mögliche Ursache des pulmo-renalen Syndroms.

Vascular Endothelial Dysfunction during Cardiac Surgery: On-Pump versus Off-Pump Coronary Surgery

BACKGROUND

Cardiac surgery often causes ischemia and development of a systemic inflammatory response syndrome, which impairs vascular barrier function, normally maintained by the endothelial cell line and the endothelial glycocalyx (EG). The EG normally covers and protects healthy endothelial cells throughout the vasculature. The aim of the present study was to assess the disruption of the cellular part of the microvascular barrier by determining parameters of endothelial cell activation known to influence and reflect cell-cell junctional integrity. Particular attention was placed on angiopoietins and their important effects on endothelial gap junctions. Furthermore, comparative measurements were undertaken in patients undergoing on- and off-pump cardiac surgery, the latter group presumably experiencing less ischemic stress.

METHODS

30 patients undergoing elective coronary artery bypass surgery were assigned to the conventional coronary artery bypass (CCAB) group (n = 15) or the off-pump coronary artery bypass grafting (OPCAB) group (n = 15). Blood samples were obtained for measuring angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2), vascular endothelial (VE)-cadherin, and endocan at various time points.

RESULTS

There were significant increases in all measured parameters in both study groups versus the respective basal values. Maximal increases were as follows: Ang-1: CCAB +220%, OPCAB +166%, p < 0.05 each; Ang-2: CCAB +150%, OPCAB +20%, p < 0.05 each; VE-cadherin: CCAB +87%, OPCAB +66%, p < 0.05 each; endocan: CCAB +323%, OPCAB +72%, p < 0.05 each.

CONCLUSION

The present study demonstrates the activation of endothelial cells, shedding of cell-cell contacts and a potential intrinsic counterregulation by Ang-1 and endocan in patients undergoing major cardiac surgery. Quantitatively greater deviations of parameters in the CCAB than in the OPCAB group suggest a relation between the occurrence of ischemia/reperfusion and the extent of endothelial activation.

Hyponatremia upon presentation to the emergency department - the need for urgent neuroimaging studies

This study aims to evaluate the necessity of urgent neuroimaging for emergency admissions exhibiting symptomatology of profound hyponatremia. We retrospectively analyzed the medical records of all patients admitted to the emergency room of the University Hospital Münster from 2010 to 2014 with a serum sodium value < 125 mmol/L. From 52918 emergency admissions, 261 patients with profound hyponatremia were identified, of whom 140 (54%) had neurological symptoms. Unspecific weakness and confusion were the most prevalent of these symptoms (59%). Focal neurological signs [FNS] were present in 31% of cases and neuroimaging was performed in 68% (95/140) of symptomatic patients. Multiple logistic regression analysis identified FNS, seizures, altered consciousness and age as independent predictors for conducting neuroimaging (all p < 0.05). Significant pathological findings consistent with acute symptomatology were evident in 17 cases, all of whom had FNS. Recursive partitioning analyses confirmed FNS as the best predictor of neuroimaging pathology (p < 0.001). Absence of FNS had a negative predictive value of 100% [95% confidence interval: 93-100%] for excluding neuroimaging pathology. In conclusion, emergency patients with profound hyponatremia frequently show nonspecific-neurological symptoms and may undergo neuroimaging unnecessarily. The lack of FNS may serve as a valuable criterion for withholding neuroimaging until hyponatremia has been corrected.

Endothelial glycocalyx breakdown is mediated by angiopoietin-2

AIMS

The endothelial glycocalyx (eGC), a carbohydrate-rich layer lining the luminal surface of the endothelium, provides a first vasoprotective barrier against vascular leakage and adhesion in sepsis and vessel inflammation. Angiopoietin-2 (Angpt-2), an antagonist of the endothelium-stabilizing receptor Tie2 secreted by endothelial cells, promotes vascular permeability through cellular contraction and junctional disintegration. We hypothesized that Angpt-2 might also mediate the breakdown of the eGC.

METHODS AND RESULTS

Using confocal and atomic force microscopy, we show that exogenous Angpt-2 induces a rapid loss of the eGC in endothelial cells in vitro. Glycocalyx deterioration involves the specific loss of its main constituent heparan sulphate, paralleled by the secretion of the heparan sulphate-specific heparanase from late endosomal/lysosomal stores. Corresponding in vivo experiments revealed that exogenous Angpt-2 leads to heparanase-dependent eGC breakdown, which contributes to plasma leakage and leukocyte recruitment in vivo.

CONCLUSION

Our data indicate that eGC breakdown is mediated by Angpt-2 in a non-redundant manner.

Sepsis recognition in the emergency department - impact on quality of care and outcome?

Background

Appropriate and timely recognition of sepsis is a prerequisite for starting goal-directed therapy bundles. We analyzed the appropriateness of sepsis recognition and documentation with regard to adequacy of therapy and outcome in an internal medicine emergency department (ED).

Methods

This study included 487 consecutive patients ≥18 years of age who presented to a university hospital ED during a 4-week period. Clinical, laboratory, and follow-up data were acquired independently from documentation by ED physicians. The study team independently rated quality of sepsis classification (American College of Chest Physicians/Society of Critical Care Medicine definitions), diagnostic workup, and guideline-adherent therapy in the ED.

Results

Of 487 included patients, 110 presented because of infection. Of those, 54 patients matched sepsis criteria, including 20 with organ damage and thus severe sepsis, as rated by the study team. Sepsis was not recognized in 32 of these 54 cases (59%). Multivariate binary logistic regression analysis revealed that higher systolic blood pressure (p <0.05), the ability to stand (p <0.01) and a low number of documented vital signs in the ED discharge letter (p < 0.05) were independent predictors of missed sepsis. Surprisingly, adequate detection of the septic focus (81 vs. 93%, p = 0.17), appropriate fluid administration (86 vs. 87%, p = 0.39), and guideline-adherent antibiotic regimen (95 vs. 100%, p = 0.42) did not differ between cases of recognized and unrecognized sepsis, respectively. Non-recognition affected neither death-censored length of hospital stay (median 7.63 d vs. 7.13 d, p = 0.42) nor a combined endpoint of death or ICU admission to (9 vs. 12%, p = 0.55).

Conclusions

Non-recognition of sepsis in ED patients with serious infections who formally meet organizational sepsis definitions seems to have no deleterious impact on initial therapy adequacy.

Electronic supplementary material

The online version of this article (doi:10.1186/s12873-017-0122-9) contains supplementary material, which is available to authorized users.

Impact of High-Cut-Off Dialysis on Renal Recovery in Dialysis-Dependent Multiple Myeloma Patients: Results from a Case-Control Study

Background

High-cut-off hemodialysis (HCO-HD) can effectively reduce high concentrations of circulating serum free light chains (sFLC) in patients with dialysis-dependent acute kidney injury (AKI) due to multiple myeloma (MM). Therefore, the aim of this study was to analyze renal recovery in a retrospective single-center cohort of dialysis-dependent MM patients treated with either conventional HD (conv. HD) or HCO-HD.

Methods and Results

The final cohort consisted of 59 patients treated with HCO-HD (n = 42) or conv. HD (n = 17). A sustained sFLC response was detected in a significantly higher proportion of HCO-HD patients (83.3%) compared with conv. HD patients (29.4%; p = 0.007). The median duration of sFLC required to reach values <1000 mg/l was 14.5 days in the HCO-HD group and 36 days in the conv. HD group. The corresponding rates of renal recovery were 64.3% and 29.4%, respectively (chi-squared test, p = 0.014). Multivariate regression and decision tree analysis (recursive partitioning) revealed HCO-HD (adjusted odds ratio [OR] 6.1 [95% confidence interval (CI) 1.5–24.5], p = 0.011) and low initial uric acid values (adjusted OR 1.3 [95%CI 1.0–1.7], p = 0.045) as independent and paramount variables associated with a favorable renal outcome.

Conclusions

In summary, the results from this retrospective case-control study suggest in addition to novel agent-based chemotherapy a benefit of HCO-HD in sFLC removal and renal outcome in dialysis-dependent AKI secondary to MM. This finding was especially pertinent in patients with low initial uric acid values, resulting in a promising renal recovery rate of 71.9%. Further prospective studies are warranted.