Extracorporeal renal replacement therapies in the treatment of sepsis: where are we?

Blood Purification in Patients with Sepsis Associated with Acute Kidney Injury: A Narrative Review

Sepsis leads to organ dysfunction. Acute kidney injury, a common type of organ dysfunction, is associated with a high mortality rate in patients with sepsis. Kidney replacement therapy can correct the metabolic, electrolyte, and fluid imbalances caused by acute kidney injury. While this therapy can improve outcomes, evidence of its beneficial effects is lacking. Herein, we review the indications for blood purification therapy, including kidney replacement therapy, and the current knowledge regarding acute kidney injury in terms of renal and non-renal indications. While renal indications have been well-documented, indications for blood purification therapy in sepsis (non-renal indications) remain controversial. Excessive inflammation is an important factor in the development of sepsis; blood purification therapy has been shown to reduce inflammatory mediators and improve hemodynamic instability. Given the pathophysiology of sepsis, blood purification therapy may decrease mortality rates in these patients. Further trials are needed in order to establish the effectiveness of blood purification therapy for sepsis.

Use of CytoSorb in the emergency department-high dependency unit: A case report and a mini review

Circulating inflammatory mediators and cytokines play a pivotal role in the progression of sepsis, leading in turn to septic shock, organ failure and resistance to standard therapy. Blood purification therapies may be adjuvant treatment for severe sepsis, but results have been shown to be so far controversial. Recently, CytoSorb has achieved promising outcomes on reduction of cytokine blood levels, improvement of clinical parameters and mortality in sepsis, as well as in other acute conditions. It is mostly used in Intensive Care Unit (ICU), in isolated hemoperfusion, or inserted in other circuits in addition to Continuous Renal Replacement Therapy (CRRT), heart-lung machines and extracorporeal membrane oxygenation. We report a case of septic shock occurred in our Emergency Department-High Dependency Unit (ED-HDU), resistant to standard therapy and improved after CytoSorb, so avoiding ICU hospitalization.

Circ_0091702 serves as a sponge of miR-545-3p to attenuate sepsis-related acute kidney injury by upregulating THBS2

Circular RNA (circRNA) has been shown to play an important function in the progression of human diseases, including sepsis with acute kidney injury (AKI). However, the role and mechanism of circ_0091702 in sepsis-induced AKI have yet to be confirmed. Lipopolysaccharide (LPS) was used to induce HK2 cells to construct AKI cell models in vitro. Quantitative real-time PCR was used to measure the expression of circ_0091702, inflammatory cytokines, microRNA (miR)-545-3p and thrombospondin 2 (THBS2). Cell counting kit 8 assay and flow cytometry were used to assess cell viability and apoptosis. Besides, the protein levels of apoptosis markers and THBS2 were evaluated by western blot analysis. In addition, the concentrations of inflammatory cytokines were detected by enzyme-linked immunosorbent assay (ELISA). Cell oxidative stress was determined by detecting the contents of oxidative stress markers. Dual-luciferase reporter assay and RIP assay were used to confirm the relationship between miR-545-3p and circ_0091702 or miR-545-3p and THBS2. Circ_0091702 was downregulated in septic AKI patients and LPS-induced HK2 cells. Circ_0091702 could attenuate LPS-induced HK2 cell injury, while its silencing had an opposite effect. In the terms of mechanism, circ_0091702 could act as a sponge of miR-545-3p, and miR-545-3p could directly target THBS2. Functional experiments revealed that miR-545-3p could reverse the alleviating effect of circ_0091702 on LPS-induced HK2 cell injury, and THBS2 knockdown also could overturn the suppressing effect of miR-545-3p inhibitor on LPS-induced HK2 cell injury. Additionally, we also suggested that circ_0091702 could sponge miR-545-3p to regulate THBS2 expression. In conclusion, our results showed that circ_0091702 could suppress LPS-induced HK2 cell injury via the miR-545-3p/THBS2 axis, indicating that circ_0091702 might be an important biomarker for relieving sepsis-related AKI.

Peritoneal dialysis in children with sepsis-associated AKI (SA-AKI): an experience in a low- to middle-income country

Background: In critically ill children, sepsis-associated acute kidney injury (SA-AKI) has significant morbidity and mortality.Aim: To estimate whether early initiation of peritoneal dialysis (PD) has a better short-term outcome than standard PD.Methods: Early PD (n = 25) was defined as a need for PD in Kidney Disease: Improving Global Outcomes (KDIGO) stage 2 AKI, while those fulfilling the criteria for stage 3 KDIGO were categorised as a standard PD group (n = 25). The primary outcome measure was the estimated glomerular filtration rate (eGFR) at discharge or at 4 weeks after initiation of PD, whichever occurred earlier.Results: A prospective cohort of 50 children (32 boys) aged 2 months to 16 years with SA-AKI who underwent PD were recruited. The most frequent indication for PD was fluid overload (40%), followed by persistent metabolic acidosis (36%). Children in the early PD group had lower creatinine and higher eGFR at discharge/4-week follow-up (p < 0.001). The duration of PD was less if it was commenced early (p < 0.04); 24 of 25 (96%) children in the early PD group were off PD within 6 days of initiation compared with 13 of 25 (52%) in the standard PD group (p < 0.001).Conclusions: Compared with standard PD, early PD in SA-AKI resulted in a favourable renal outcome, decreased duration of PD and early discontinuation of dialysis.Abbreviations : AKI: acute kidney injury; CRRT: continuous renal replacement therapy; CS-AKI: cardiac surgery-associated acute kidney injury; eGFR: estimated glomerular filtration rate; ELAIN: early versus late initiation of renal replacement therapy in critically ill patients with acute kidney injury; ESCAPE: effect of strict blood pressure control and ACE inhibition on the progression of chronic kidney disease in paediatric patients; HIC: high-income countries; ISN: international society of nephrology; KDIGO: Kidney Disease: Improving Global Outcomes; LMIC: low- to middle-income countries; PD: peritoneal dialysis; PICU: paediatric intensive care unit; RRT: renal replacement therapy; SA-AKI: sepsis-associated acute kidney injury; SYL: Saving Young Lives; SOFA: sequential (sepsis-related) organ failure assessment score; STARRT-AKI: standard versus accelerated initiation of renal replacement therapy in acute kidney injury.

An update on membranes and cartridges for extracorporeal blood purification in sepsis and septic shock

PURPOSE OF REVIEW

This review aims to summarize the most recent advances on different membranes and cartridges used for extracorporeal blood purification in critically ill patients with sepsis or septic shock.

RECENT FINDINGS

Despite positive signals from experimental, cases and small clinical studies, blood purification showed no distinct morbidity and mortality benefit in large clinical trials.

SUMMARY

None of the discussed specific membranes or cartridges can currently be recommended as sole adjunctive treatment in sepsis and septic shock. Any available technique should be timely initiated and adapted to the patient's status. Sickest patients seem to benefit more from blood purification. Patient selection is thus of crucial importance and may be optimized by focusing on disease severity and degree of organ failure. Measurement of endotoxin activity and plasma procalcitonin levels can support the selection process but ideal cutoff values need to be defined. Well-designed prospective randomized clinical trials assessing or comparing the various available membranes and cartridges are eagerly awaited.

Invasive Meningococcal Disease in the Vaccine Era

Infection with the meningococcus is one of the main causes of meningitis and septicaemia worldwide. Humans are the only natural reservoir for the meningococcus which is found primarily as a commensal inhabitant in the nasopharynx in ~10% of adults, and may be found in over 25% of individuals during adolescence. Prompt recognition of meningococcal infection and early aggressive treatment are essential in order to reduce mortality, which occurs in up to 10% of those with invasive meningococcal disease (IMD). This figure may be significantly higher in those with inadequate or delayed treatment. Early administration of effective parenteral antimicrobial therapy and prompt recognition and appropriate management of the complications of IMD, including circulatory shock and raised intracranial pressure (ICP), are critical to help improve patient outcome. This review summarizes clinical features of IMD and current treatment recommendations. We will discuss the evidence for immunization and effects of vaccine strategies, particularly following implementation of effective vaccines against Group B meningococcus.

Renal protection in cardiovascular surgery

Acute kidney injury (AKI) is one of the most relevant complications after major surgery and is a predictor of mortality. In Western countries, patients at risk of developing AKI are mainly those undergoing cardiovascular surgical procedures. In this category of patients, AKI depends on a multifactorial etiology, including low ejection fraction, use of contrast media, hemodynamic instability, cardiopulmonary bypass, and bleeding. Despite a growing body of literature, the treatment of renal failure remains mainly supportive (e.g. hemodynamic stability, fluid management, and avoidance of further damage); therefore, the management of patients at risk of AKI should aim at prevention of renal damage. Thus, the present narrative review analyzes the pathophysiology underlying AKI (specifically in high-risk patients), the preoperative risk factors that predispose to renal damage, early biomarkers related to AKI, and the strategies employed for perioperative renal protection. The most recent scientific evidence has been considered, and whenever conflicting data were encountered possible suggestions are provided.