Extracorporeal blood purification for sepsis

Extracorporeal blood purification strategies in sepsis and septic shock: An insight into recent advancements

BACKGROUND

Despite various therapies to treat sepsis, it is one of the leading causes of mortality in the intensive care unit patients globally. Knowledge about the pathophysiology of sepsis has sparked interest in extracorporeal therapies (ECT) which are intended to balance the dysregulation of the immune system by removing excessive levels of inflammatory mediators.

AIM

To review recent data on the use of ECT in sepsis and to assess their effects on various inflammatory and clinical outcomes.

METHODS

In this review, an extensive English literature search was conducted from the last two decades to identify the use of ECT in sepsis. A total of 68 articles from peer-reviewed and indexed journals were selected excluding publications with only abstracts.

RESULTS

Results showed that ECT techniques such as high-volume hemofiltration, coupled plasma adsorption/filtration, resin or polymer adsorbers, and CytoSorb^® are emerging as adjunct therapies to improve hemodynamic stability in sepsis. CytoSorb^® has the most published data in regard to the use in the field of septic shock with reports on improved survival rates and lowered sequential organ failure assessment scores, lactate levels, total leucocyte count, platelet count, interleukin- IL-6, IL-10, and TNF levels.

CONCLUSION

Clinical acceptance of ECT in sepsis and septic shock is currently still limited due to a lack of large random clinical trials. In addition to patient-tailored therapies, future research developments with therapies targeting the cellular level of the immune response are expected.

Cytokine storm and COVID-19: a chronicle of pro-inflammatory cytokines

Coronavirus disease 2019 (COVID-19) has swept the world, unlike any other pandemic in the last 50 years. Our understanding of the disease has evolved rapidly since the outbreak; disease prognosis is influenced mainly by multi-organ involvement. Acute respiratory distress syndrome, heart failure, renal failure, liver damage, shock and multi-organ failure are strongly associated with morbidity and mortality. The COVID-19 disease pathology is plausibly linked to the hyperinflammatory response of the body characterized by pathological cytokine levels. The term 'cytokine storm syndrome' is perhaps one of the critical hallmarks of COVID-19 disease severity. In this review, we highlight prominent cytokine families and their potential role in COVID-19, the type I and II interferons, tumour necrosis factor and members of the Interleukin family. We address various changes in cellular components of the immune response corroborating with changes in cytokine levels while discussing cytokine sources and biological functions. Finally, we discuss in brief potential therapies attempting to modulate the cytokine storm.

Fulminant encephalopathy in a child with hyperferritinemic sepsis: a case report

Background

Sepsis-associated encephalopathy (SAE) is epidemic in intensive care units and recognized as a fatal complication of sepsis. SAE is characterized by diffuse brain dysfunction and the correct diagnosis of SAE requires ruling out direct central nervous system (CNS) infection or other types of encephalopathy, such as hepatic encephalopathy, pulmonary encephalopathy, and other encephalopathy.

Case presentation

We reported a rare case of a 5-year-old girl who presented with abdominal pain, vomiting, recurrent seizures, and coma. Brain magnetic resonance imaging (MRI) showed diffuse white matter abnormalities in the brain on day 1. Cerebrospinal fluid (CSF) tests revealed that protein levels and glucose levels were normal without pleocytosis. CSF PCRs for pathogens were all negative. The electroencephalography examination demonstrated diffuse, generalized and slow background activity. The patient showed the symptom of hyperferritinemic sepsis with multiple organ dysfunction syndrome (MODS). SAE was also diagnosed by ruling out other encephalitis or encephalopathy. The patient made marked improvements of clinical symptoms and the lesions on brain imaging disappeared completely within two months after appropriate treatment including antibiotic treatments, methylprednisolone, intravenous immunoglobulin, membrane-based therapeutic plasma exchange (TPE), and continuous renal replacement therapy (CRRT).

Conclusions

SAE can be a fatal complication of sepsis which asks for immediate diagnosis and treatment. Few reports have focus on MRI imaging findings on the early onset of hyperferritinemic sepsis with MODS since these children were too ill to undergo an MRI scan. However, SAE might appear before other systemic features of sepsis are obvious, and MRI could show abnormal lesion in the brain during the early course. Therefore, MRI should be performed early to diagnose this fatal complication which would play important roles in improving the clinical outcomes by early initiation with appropriate treatments.

Experience with hemoadsorption (CytoSorb®) in the management of septic shock patients

BACKGROUND

Cytokines and inflammatory mediators are the hallmarks of sepsis. Extracorporeal cytokine hemoadsorption devices are the newer clinical support system to overcome the cytokine storm during sepsis.

AIM

To retrospectively evaluate the clinical outcomes of patients admitted in intensive care unit with septic shock with different etiologies.

METHODS

The laboratory parameters including biomarkers such as procalcitonin, serum lactate and C-reactive protein; and the hemodynamic parameters; mean arterial pressure, vasopressor doses, sepsis scores, cytokine levels and other vital parameters were evaluated. We evaluated these outcomes among survivors and non-survivors.

RESULTS

Of 100 patients evaluated, 40 patients survived. Post treatment, the vasopressors dosage remarkably decreased though it was not statistically different; 34.15% (P = 0.0816) for epinephrine, 20.5 % for norepinephrine (P = 0.3099) and 51% (P = 0.0678) for vasopressin. In the survivor group, a remarkable reduction of biomarkers levels; procalcitonin (65%, P = 0.5859), C-reactive protein (27%, P = 0.659), serum lactate (27%, P = 0.0159) and bilirubin (43.11%; P = 0.0565) were observed from baseline after CytoSorb^® therapy. A significant reduction in inflammatory markers; interleukin 6 and interleukin 10; (87% and 92%, P < 0.0001) and in tumour necrosis factor (24%, P = 0.0003) was also seen. Overall, 28 (28%) patients who were given CytoSorb^® therapy less than 48 h after onset of septic shock survived and the maximum duration of stay for 70% of these patients in intensive care unit was less than 15 d.

CONCLUSION

CytoSorb^® is a safe and well tolerated rescue therapy option in patients with septic shock. However, early (preferably within < 48 h after onset of septic shock) initiation could result in better clinical outcomes. Further randomized trials are needed to define the potential benefits of this new treatment modality.

Hemofiltration in Patients with Severe Acute Pancreatitis (Review)

Questions regarding the application of extracorporeal detoxification to patients with severe acute pancreatitis have been considered. Hemodialysis, the historically first method of extracorporeal detoxification for such patients, has been also described in the review. Appropriateness of using renal replacement therapy methods and among them continued renal replacement therapy has been shown. Hemofiltration and hemodiafiltration technologies are described in detail including different modes of their application and the possibility of using various types of filters. Available data on hemofiltration for patients with severe acute pancreatitis have been analyzed. Great attention is paid to the unsolved aspects of hemofiltration in severe acute pancreatitis such as determining renal and extrarenal indices; time of starting hemofiltration; selection of volume replacement modes and a buffer system; procedure duration; anticoagulation measures, defining criteria to assess the adequacy of hemofiltration, state severity, and organ dysfunction degree. Further multicenter investigations are necessary to be able to assess the efficacy of the hemofiltration procedures on the basis of the thoroughly worked out and pathogenically grounded protocol using adequate control methods taking into consideration endogenic intoxication phases and intensity of the multiple organ failure syndrome.

A potential peptide derived from cytokine receptors can bind proinflammatory cytokines as a therapeutic strategy for anti-inflammation

Chronic inflammation is a pivotal event in the pathogenesis of cardiovascular diseases, including atherosclerosis, restenosis, and coronary artery disease. The efficacy of current treatment or preventive strategies for such inflammation is still inadequate. Thus, new anti-inflammatory strategies are needed. In this study, based on molecular docking and structural analysis, a potential peptide KCF18 with amphiphilic properties (positively charged and hydrophobic residues) derived from the receptors of proinflammatory cytokines was designed to inhibit cytokine-induced inflammatory response. Simulations suggested that KCF18 could bind to cytokines simultaneously, and electrostatic interactions were dominant. Surface plasmon resonance detection showed that KCF18 bound to both tumor necrosis factor-α (TNF-α) and interleukin-6, which is consistent with MM/PBSA binding free energy calculations. The cell experiments showed that KCF18 significantly reduced the binding of proinflammatory cytokines to their cognate receptors, suppressed TNF-α mRNA expression and monocyte binding and transmigration, and alleviated the infiltration of white blood cells in a peritonitis mouse model. The designed peptide KCF18 could remarkably diminish the risk of vascular inflammation by decreasing plasma cytokines release and by directly acting on the vascular endothelium. This study demonstrated that a combination of structure-based in silico design calculations, together with experimental measurements can be used to develop potential anti-inflammatory agents.

Reduction in the IL-6 level at 24 h after admission to the intensive care unit is a survival predictor for Vietnamese patients with sepsis and septic shock: a prospective study

Background

Sepsis and septic shock are common problems in intensive care units (ICUs). The mortality of patients with sepsis or septic shock is high. We investigated if reduction in the serum concentration of the cytokines tumor necrosis factor α, interleukin (IL)-6 and IL-10, and the rate of change in the IL-6 level at 24 h after ICU admission were survival predictors for patients with sepsis and septic shock in a Vietnamese population.

Methods

This was a prospective study conducted at an ICU in Cho Ray Hospital, Vietnam, from October 2014 to October 2016. Patients diagnosed with sepsis or septic shock using validated international guidelines were enrolled. Plasma samples were collected upon (T₀) and 24 h after (T₂₄) ICU admission for measurement of cytokine concentrations. Blood tests were done to detect organ dysfunction. The duration of ICU stays, hospital stay, APACHE II and SOFA scores, and the in-hospital mortality were compared between survival and non-survival groups. Univariate logistic regression and multivariate analysis were done to determine the association between survival and IL-6 reduction at 24 h after ICU admission.

Results

A total of 123 patients were enrolled. The concentration (in pg/mL) of IL-6 at T_o was 413.3 in survivors and 530.0 in non- survivors. At T₂₄, the IL-6 level was 65.4 for survivors and 286.9 for non-survivors. The survival rate was 39.0%. At T₂₄, the concentrations of IL-6 and the reduction in IL-6 level were predictors of survival in patients with sepsis and septic shock. We found a significant association between IL-6 reduction and survival at ≥86% with Odds Ratio (OR) 5.67, 95% Confidence Interval (CI); 1.27–25.3, compared with an increase in the IL-6 rate of change.

Conclusions

Our findings suggested that a reduction in the IL-6 level of ≥86% at 24 h from ICU admission is a survival predictor for patients with sepsis and septic shock in our population.

Early application of continuous high-volume haemofiltration can reduce sepsis and improve the prognosis of patients with severe burns

Background

In the early stage of severe burn, patients often exhibit a high level of inflammatory mediators in blood and are likely to develop sepsis. High-volume haemofiltration (HVHF) can eliminate these inflammatory mediators. We hypothesised that early application of HVHF may be beneficial in reducing sepsis and improving the prognosis of patients with severe burns.

Methods

Adults patients with burns ≥ 50% total burn surface area (TBSA) and in whom the sum of deep partial and full-thickness burn areas was ≥ 30% were enrolled in this randomised prospective study, and they were divided into control (41 cases) and HVHF (41 cases) groups. Patients in the control group received standard management for major burns, whereas the HVHF group additionally received HVHF treatment (65 ml/kg/h for 3 consecutive days) within 3 days after burn. The incidence of sepsis and mortality, some laboratory data, levels of inflammatory cytokines in the blood, HLA-DR expression on CD14⁺ peripheral blood monocytes, the proportion of CD25⁺Foxp3⁺ in CD4⁺ T lymphocytes, and the counts of CD3⁺, CD4⁺ and CD8⁺ T lymphocytes were recorded within 28 days post-burn.

Results

The incidence of sepsis, septic shock and duration of vasopressor treatment were decreased significantly in the HVHF group. In addition, in the subgroup of patients with burns ≥ 80% TBSA, the 90-day mortality showed significant decreases in the HVHF group. The ratio of arterial oxygen partial pressure to the fraction of inspiration oxygen was improved after HVHF treatment. In the patients who received HVHF treatment, the blood levels of inflammatory cytokines, including tumour necrosis factor-α, interleukin (IL)-1β, IL-6 and IL-8, as well as the blood level of procalcitonin were found to be lower than in the control group. Moreover, higher HLA-DR expression on CD14⁺ monocytes and a lower proportion of CD25⁺Foxp3⁺ in CD4⁺ T lymphocytes were observed in the patients in the HVHF group.

Conclusions

Early application of HVHF benefits patients with severe burns, especially for those with a greater burn area (≥ 80% TBSA), decreasing the incidence of sepsis and mortality. This effect may be attributed to its early clearance of inflammatory mediators and the recovery of the patient’s immune status.

Trial registration

Chinese Clinical Trial Register, ChiCTR-TRC-12002616. Registered on 24 October 2012.

Electronic supplementary material

The online version of this article (10.1186/s13054-018-2095-9) contains supplementary material, which is available to authorized users.

Broad adsorption of sepsis-related PAMP and DAMP molecules, mycotoxins, and cytokines from whole blood using CytoSorb® sorbent porous polymer beads

OBJECTIVE

Sepsis is defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. In sepsis and septic shock, pathogen-associated molecular pattern molecules (PAMPS), such as bacterial exotoxins, cause direct cellular damage and/or trigger an immune response in the host often leading to excessive cytokine production, a maladaptive systemic inflammatory response syndrome response (SIRS), and tissue damage that releases DAMPs, such as activated complement and HMGB-1, into the bloodstream causing further organ injury. Cytokine reduction using extracorporeal blood filtration has been correlated with improvement in survival and clinical outcomes in experimental studies and clinical reports, but the ability of this technology to reduce a broader range of inflammatory mediators has not been well-described. This study quantifies the size-selective adsorption of a wide range of sepsis-related inflammatory bacterial and fungal PAMPs, DAMPs and cytokines, in a single compartment, in vitro whole blood recirculation system.

MEASUREMENTS AND MAIN RESULTS

Purified proteins were added to whole blood at clinically relevant concentrations and recirculated through a device filled with CytoSorb® hemoadsorbent polymer beads (CytoSorbents Corporation, USA) or control (no bead) device in vitro. Except for the TNF-α trimer, hemoadsorption through porous polymer bead devices reduced the levels of a broad spectrum of cytokines, DAMPS, PAMPS and mycotoxins by more than 50 percent.

CONCLUSIONS

This study demonstrates that CytoSorb® hemoadsorbent polymer beads efficiently remove a broad spectrum of toxic PAMPS and DAMPS from blood providing an additional means of reducing the uncontrolled inflammatory cascade that contributes to a maladaptive SIRS response, organ dysfunction and death in patients with a broad range of life-threatening inflammatory conditions such as sepsis, toxic shock syndrome, necrotizing fasciitis, and other severe inflammatory conditions.

Escherichia coli outer membrane vesicles can contribute to sepsis induced cardiac dysfunction

Sepsis induced cardiac dysfunction (SIC) is a severe complication to sepsis which significantly worsens patient outcomes. It is known that bacteria have the capacity to release outer membrane vesicles (OMVs), which are nano-sized bilayered vesicles composed of lipids and proteins, that can induce a fatal inflammatory response. The aim of this study was to determine whether OMVs from a uropathogenic Escherichia coli strain can induce cardiac dysfunction, and to elucidate any mechanisms involved. OMVs induced irregular Ca²⁺ oscillations with a decreased frequency in cardiomyocytes through recordings of intracellular Ca²⁺ dynamics. Mice were intraperitoneally injected with bacteria-free OMVs, which resulted in increased concentration of pro-inflammatory cytokine levels in blood. Cytokines were increased in heart lysates, and OMVs could be detected in the heart after OMVs injection. Troponin T was significantly increased in blood, and echocardiography showed increased heart wall thickness as well as increased heart rate. This study shows that E. coli OMVs induce cardiac injury in vitro and in vivo, in the absence of bacteria, and may be a causative microbial signal in SIC. The role of OMVs in clinical disease warrant further studies, as bacterial OMVs in addition to live bacteria may be good therapeutic targets to control sepsis.