Hemodialysis effect on platelet count and function and hemodialysis-associated thrombocytopenia

Decrease in platelet count in patients with AKI and its association with major adverse kidney events

INTRODUCTION

A reduction in platelet count in critically ill patients is a marker of severity of the clinical condition. However, whether this association holds true in acute kidney injury (AKI) is unknown. We analyzed the association between platelet reduction in patients with AKI and major adverse kidney events (MAKE).

METHODS

In this retrospective cohort, we included AKI patients at the Hospital Civil of Guadalajara, in Jalisco, Mexico. Patients were divided according to whether their platelet count fell >21% during the first 10 days. Our objectives were to analyze the associations between a platelet reduction >21% and MAKE at 10 days (MAKE10) or at 30-90 days (MAKE30-90) and death.

RESULTS

From 2017 to 2023, 400 AKI patients were included, 134 of whom had a > 21% reduction in platelet count. The mean age was 54 years, 60% were male, and 44% had sepsis. The mean baseline platelet count was 194 x 103 cells/µL, and 65% of the KDIGO3 patients met these criteria. Those who underwent hemodialysis (HD) had lower platelet counts. After multiple adjustments, a platelet reduction >21% was associated with MAKE10 (OR 4.2, CI 2.1-8.5) but not with MAKE30-90. The mortality risk increased 3-fold (OR 2.9, CI 1.1-7.7, p = 0.02) with a greater decrease in the platelets (<90 x 103 cells/µL). As the platelets decreased, the incidence of MAKE was more likely to increase. These associations lost significance when accounting for starting HD.

CONCLUSION

In our retrospective cohort of patients with AKI, a > 21% reduction in platelet count was associated with MAKE. Our results are useful for generating hypotheses and motivating us to continue studying this association with a more robust design.

A comparative study on the haemostatic changes in kidney failure patients: Pre- and post- haemodialysis and haemodiafiltration

BACKGROUND

Individuals with kidney failure have a compromised haemostatic system making them susceptible to both thrombosis and bleeding.

OBJECTIVES

Assessment of primary haemostasis in patients treated with either haemodialysis (HD) or haemodiafiltration (HDF) was performed through the measurement of several coagulation-based tests, both pre- and post-dialysis.

PATIENTS/METHODS

41 renal failure patients and 40 controls were recruited. Platelet aggregometry, Factor XIII (FXIII), Fibrinogen, Von Willebrand Factor (VWF) and Soluble P-Selectin (sP-Sel) levels were measured.

RESULTS

Maximum platelet aggregation was diminished in renal patients irrespective of aspirin intake. Post-dialysis, platelet function was exacerbated. Pre-dialysis FXIII levels were similar to the healthy cohort and became elevated post-dialysis. This elevation could not be explained by the relative decrease of water by dialysis. Fibrinogen levels were already elevated pre-dialysis and further increased post-dialysis. This elevation was associated with the relative decrease of water by dialysis. VWF levels in males were similar to the healthy cohort and became elevated post-dialysis. This elevation was associated with dialysis-related water loss. VWF antigen and activity in female patients were already elevated pre-dialysis and further increased post-dialysis with the exception of VWF activity in HDF treated female patients. sP-Sel levels were lower than those of the healthy cohort and became similar to the healthy cohort post-dialysis. This elevation could not be explained by the relative decrease of water by dialysis.

CONCLUSIONS

Whilst platelet aggregometry was diminished, we noted elevated clotting factors such as fibrinogen, FXIII and VWF with no significant differences between HD and HDF-treated patients.

Blood Purification in Hepatic Dysfunction after Liver Transplant or Extensive Hepatectomy: Far from the Best-Case Scenarios

Background: Hepatic dysfunction (HD) after liver transplantation (LT) or extended hepatic resection (EHR) is associated with graft failure and high short-term mortality. We evaluated the safety and depurative efficacy of CytoSorb® in these settings. The primary endpoint was the change in serum total bilirubin at the end of the treatment compared to the baseline value. The secondary endpoint was to evaluate the trend of serum total bilirubin and coagulation parameters up to 72 h after discontinuation of CytoSorb®. The effects of CytoSorb® therapy on the degree of hepatic encephalopathy (HE), Sequential Organ Failure Assessment (SOFA), and Model for End-Stage Liver Disease (MELD) scores as well as the hemodynamic status compared to baseline were also assessed. Methods: Adult patients with a serum total bilirubin level > 10 mg/dL admitted to the Intensive Care Unit were included. Exclusion criteria were hemodynamic instability, postoperative bleeding and platelet count < 20,000/mm3. Results: Seven patients were treated. Serum total bilirubin was significantly reduced at the end of treatment. However, seventy-two hours after the discontinuation of extracorporeal therapy, bilirubin levels returned to baseline levels in four patients. A decrease in platelet count was found during therapy, and platelet transfusion was required in six cases. A significant increase in D-dimer at the end of treatment was detected. HE degree, SOFA and MELD scores remained stable, while a deterioration in hemodynamic status was observed in two cases. Conclusions: Our preliminary findings did not show the possible benefits of CytoSorb® in rebalancing clinical and laboratory parameters in patients with HD after LT or EHR.

Clinical Impact of the Use of Warfarin in Patients with Atrial Fibrillation Undergoing Maintenance Hemodialysis

Background: We evaluated the impact of warfarin use on the clinical outcomes of patients with atrial fibrillation who were undergoing hemodialysis (HD). Methods: A retrospective analysis was conducted utilizing data from patients undergoing maintenance HD who participated in HD quality assessment programs. Patients who were assigned the diagnostic code for atrial fibrillation (n = 4829) were included and divided into two groups based on the use of warfarin: No group (no warfarin prescriptions (n = 4009)), and Warfarin group (warfarin prescriptions (n = 820)). Results: Cox regression analyses revealed that the hazard ratio for all-cause mortality in the Warfarin group was 1.15 (p = 0.005) in univariate analysis and 1.11 (p = 0.047) in multivariable analysis compared to that of the No group. Hemorrhagic stroke was significantly associated with warfarin use, but no significant association between the use of warfarin and ischemic stroke or cardiovascular events was observed. The subgroup results demonstrated similar trends. Conclusions: Warfarin use is associated with a higher risk of all-cause mortality and hemorrhagic stroke, and has a neutral effect on ischemic stroke and cardiovascular events in patients with atrial fibrillation who are undergoing HD, compared to those who are not using warfarin.

Association between systemic inflammatory indicators with the survival of chronic kidney disease: a prospective study based on NHANES

Background

systemic inflammation disorders were observed in chronic kidney disease (CKD). Whether the systemic inflammatory indicators could be optimal predictors for the survival of CKD remains less studied.

Methods

In this study, participants were selected from the datasets of the National Health and Nutrition Examination Survey (NHANES) between 1999 to 2018 years. Four systemic inflammatory indicators were evaluated by the peripheral blood tests including systemic immune-inflammation index (SII, platelet*neutrophil/lymphocyte), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), lymphocyte-to-monocyte ratio (LMR). Kaplan-Meier curves, restricted cubic spline (RCS), and Cox regression analysis were used to evaluate the association between the inflammatory index with the all-cause mortality of CKD. Receiver operating characteristic (ROC) and concordance index (C-index) were used to determine the predictive accuracy of varied systemic inflammatory indicators. Sensitive analyses were conducted to validate the robustness of the main findings.

Results

A total of 6,880 participants were included in this study. The mean age was 67.03 years old. Among the study population, the mean levels of systemic inflammatory indicators were 588.35 in SII, 2.45 in NLR, 133.85 in PLR, and 3.76 in LMR, respectively. The systemic inflammatory indicators of SII, NLR, and PLR were all significantly positively associated with the all-cause mortality of CKD patients, whereas the high value of LMR played a protectable role in CKD patients. NLR and LMR were the leading predictors in the survival of CKD patients [Hazard ratio (HR) =1.21, 95% confidence interval (CI): 1.07-1.36, p = 0.003 (3rd quartile), HR = 1.52, 95%CI: 1.35-1.72, p<0.001 (4th quartile) in NLR, and HR = 0.83, 95%CI: 0.75-0.92, p<0.001 (2nd quartile), HR = 0.73, 95%CI: 0.65-0.82, p<0.001 (3rd quartile), and = 0.74, 95%CI: 0.65-0.83, p<0.001 (4th quartile) in LMR], with a C-index of 0.612 and 0.624, respectively. The RCS curves showed non-linearity between systemic inflammatory indicators and all-cause mortality risk of the CKD population.

Conclusion

Our study highlights that systemic inflammatory indicators are important for predicting the survival of the U.S. population with CKD. The systemic inflammatory indicators would add additional clinical value to the health care of the CKD population.

Use of Thromboelastography in Coronary Artery Bypass Grafting in a Patient With Factor Ⅴ Deficiency With Platelet Function Disorders: A Case Report and Literature Review

Reports on cases of factor Ⅴ (FⅤ) deficiency complicated by platelet function disorders in patients undergoing cardiac surgery are rare, and the utilization of thromboelastography in such cases is limited. This case presents a unique case of FⅤ deficiency complicated by platelet function disorders, highlighting the significance of tailored transfusion strategies guided by thromboelastography (TEG). A 64-year-old hemodialysis patient who was diagnosed with FⅤ deficiency 24 years prior presented for an on-pump coronary artery bypass graft. The decrease in FⅤ activity on preoperative examination was mild. Based on this finding, it was determined that preoperative fresh frozen plasma supplementation was not required. However, the case was complicated by platelet function disorders; therefore, a preoperative transfusion of platelet concentrate was performed to correct the decreased platelet function, enabling subsequent surgery. Intraoperative and postoperative transfusion strategies were guided by TEG. This study highlights TEG-guided transfusion management as a viable option for patients with FⅤ deficiency complicated by platelet function disorders.

Impact of hemodialysis on efficacies of the antiplatelet agents in coronary artery disease patients complicated with end-stage renal disease

It is controversial whether hemodialysis affects the efficacy of the antiplatelet agents. We aimed to investigate the impact of hemodialysis on efficacies of the antiplatelet agents in coronary artery disease (CAD) patients complicated with end-stage renal disease (ESRD). 86 CAD patients complicated with ESRD requiring hemodialysis were consecutively enrolled. After 5-day treatment with aspirin and clopidogrel or ticagrelor, the platelet aggregations induced by arachidonic acid (PLAA) or adenosine diphosphate (PLADP), and the P2Y12 reaction unit (PRU) were measured before and after hemodialysis. The propensity matching score method was adopted to generate a control group with normal renal function from 2439 CAD patients. In patients taking aspirin, the PLAA remained unchanged after hemodialysis. In patients taking clopidogrel, the PLADP (37.26 ± 17.04 vs. 31.77 ± 16.09, p = 0.029) and corresponding clopidogrel resistance (CR) rate (23 [48.9%] vs. 14 [29.8%], p = 0.022) significantly decreased after hemodialysis, though PRU remained unchanged. Subgroup analysis indicated that PLADP significantly decreased while using polysulfone membrane (36.8 ± 17.9 vs. 31.1 ± 14.5, p = 0.024). In patients taking ticagrelor, PLADP, and PRU remained unchanged after hemodialysis. ESRD patients had higher incidences of aspirin resistance (AR) and CR compared to those with normal renal function (AR: 16.1% vs. 0%, p = 0.001; CR: 48.4% vs. 24.8%, p = 0.024). Hemodialysis does not have negative effect on the efficacies of aspirin, clopidogrel and ticagrelor in ESRD patients with CAD. ESRD patients have higher incidences of AR and CR compared with those with normal renal function.Trial registration ClinicalTrials.gov Identifier: NCT03330223, first registered January 4, 2018.

Neonatal Extracorporeal Membrane Oxygenation: Associations between Continuous Renal Replacement Therapy, Thrombocytopenia, and Outcomes

INTRODUCTION

The incidence of thrombocytopenia in neonates receiving extracorporeal membrane oxygenation (ECMO) with and without concurrent continuous renal replacement therapy (CRRT) and associated complications have not been well described. The primary aims of the current study were to (1) characterize thrombocytopenia in neonates receiving ECMO (including those treated concurrently with CRRT) and (2) evaluate risk factors (including CRRT utilization) associated with severe thrombocytopenia. In a planned exploratory secondary aim, we explored the association of severe thrombocytopenia with outcomes in neonates receiving ECMO.

METHODS

We conducted a retrospective single-center chart review of neonates who received ECMO 07/01/14-03/01/20 and evaluated associations between CRRT, severe thrombocytopenia (platelet count <50,000/mm3), and outcomes (ECMO duration, length of stay, and survival).

RESULTS

Fifty-two neonates received ECMO; 35 (67%) received concurrent CRRT. Severe thrombocytopenia occurred in 27 (52%) neonates overall and in 21 (60%) neonates who received concurrent CRRT. Underlying diagnosis, ECMO mode, care unit, and moderate/severe hemolysis differed between those who did and did not receive CRRT. CRRT receivers experienced shorter hospital stays than CRRT non-receivers, but ECMO duration, length of intensive care unit (ICU) stay, and survival did not differ between groups. CRRT receipt was associated with severe thrombocytopenia. Exploratory classification and regression tree (CART) analysis suggests CRRT use, birthweight, and ICU location are all predictors of interest for severe thrombocytopenia.

CONCLUSIONS

In our cohort, CRRT use during ECMO was associated with severe thrombocytopenia, and patients who received ECMO with CRRT experienced shorter hospital stays than those who did not receive CRRT. Exploratory CART analysis suggests CRRT use, birthweight, and ICU location are all predictors for severe thrombocytopenia and warrant further investigations in larger studies.

The efficacy and safety of continuous blood purification in neonates with septic shock and acute kidney injury: a two-center retrospective study

To investigate the efficacy and safety of continuous blood purification (CBP) in neonates with septic shock and acute kidney injury (AKI). This retrospective study was conducted at two tertiary care children's hospitals between January 2015 and May 2022. A total of 26 neonates with septic shock and AKI were included in this study, with a mortality rate of 50%. Fourteen neonates (53.8%) received continuous veno-venous hemodiafiltration, and 12 (46.2%) received continuous veno-venous hemofiltration. Compared with the indices before CBP, urine output increased 12 h after CBP initiation (P = 0.003) and serum creatinine decreased (P = 0.019). After 24 h of CBP, blood urea nitrogen had decreased (P = 0.006) and mean arterial pressure had increased (P = 0.007). At the end of CBP, the vasoactive-inotropic score and blood lactate were decreased (P = 0.035 and 0.038, respectively) and PH was increased (P = 0.015). Thrombocytopenia was the most common complication of CBP.  Conclusion: CBP can efficiently maintain hemodynamic stability, improve renal function, and has good safety in neonates with septic shock and AKI. However, the mortality rate remains high, and whether CBP improves the prognosis of neonates with septic shock and AKI remains unclear. What is Known: • Over 50% of children with septic shock have severe AKI, of which 21.6% required CBP. • The clinical application of CBP in septic shock has attracted increasing attention. What is New: • CBP can efficiently maintain hemodynamic stability, improve renal function, and has good safety in neonates with septic shock and AKI. • The mortality rate in neonates with septic shock and AKI receiving CBP remains high.

Postoperative thrombocytopenia and subsequent consequences in acute type A aortic dissection

OBJECTIVES

To ascertain if postoperative thrombocytopenia following open aortic surgery with a median sternotomy can predict early- and intermediate-term morbidity and mortality.

METHODS

From January 2018 to December 2022, a comparison was made between patients who had and didn't have postoperative thrombocytopenia (defined as a nadir < 75 × 103/μL after 72 h of open aortic surgery with median sternotomy). Intermediate-term mortality during follow-up was the main result, with cerebrovascular accident and acute renal injury requiring dialysis as secondary events. Inverse probability treatment weighting (IPTW) was used to account for selection bias between groups. The Kaplan-Meier method with the log-rank test was used to assess intermediate-term survivals following IPTW modification. To identify the nonlinear link between platelet nadir and mortality probability, a generalized additive mix model was applied. To help increase power in testing for the overall effect of platelet nadir on outcomes in the generalized additive mix model, the hazard ratios and 95% CIs for each subgroup and their interactions were examined.

RESULTS

The study included 457 patients, 347 male (75.9%), with mean age of 54 ± 12 years. The last follow-up was done on April 14th, 2023 and the median follow-up time was 16 (6-31) months. Following IPTW, patient characteristics were balanced among cohorts. Platelet nadir was found to be significantly inversely related to early-term mortality (IPTW-adjusted hazard ratio = 0.968 (0.960, 0.977), p < 0.001), and AKI requiring dialysis (IPTW-adjusted hazard ratio = 0.979 (0.971, 0.986), p < 0.001). A nonlinear relationship between platelet nadir and mortality risk probability during follow-up visually showed that the likelihood of mortality decreased with platelet nadir increased. In confounder-adjusted survival ('postoperative thrombocytopenia not acquired' vs 'postoperative thrombocytopenia'; HR: 0.086 [95% CI: 0.045-0.163]; p < 0.01) analysis, non-acquired postoperative thrombocytopenia was associated with a lower risk of mortality, and the treatment benefit was validated in IPTW-adjusted analysis, which showed an HR of 0.067.

CONCLUSIONS

Early postoperative thrombocytopenia following type A aortic dissection surgery is a risk factor for morbidity and mortality. Because postoperative thrombocytopenia can indicate a poor prognosis, monitoring early postoperative platelets helps identify individuals who may develop late postoperative problems, which is performed by this affordable biomarker.

The Crosstalk between Nephropathy and Coagulation Disorder: Pathogenesis, Treatment, and Dilemmas

ABSTRACT

The interaction between the kidney and the coagulation system greatly affects each other because of the abundant vessel distribution and blood perfusion in the kidney. Clinically, the risks of complicated thrombosis and bleeding have become important concerns in the treatment of nephropathies, especially nephrotic syndrome, CKD, ESKD, and patients with nephropathy undergoing RRTs. Adverse effects of anticoagulant or procoagulant therapies in patients with nephropathy, especially anticoagulation-related nephropathy, heparin-induced thrombocytopenia, and bleeding, seriously worsen the prognosis of patients, which have become challenges for clinicians. Over the decades, the interaction between the kidney and the coagulation system has been widely studied. However, the effects of the kidney on the coagulation system have not been systematically investigated. Although some coagulation-related proteins and signaling pathways have been shown to improve coagulation abnormalities while avoiding additional kidney damage in certain kidney diseases, their potential as anticoagulation targets in nephropathy requires further investigation. Here, we review the progression of research on the crosstalk between the coagulation system and kidney diseases and systematically analyze the significance and shortcomings of previous studies to provide new sight into future research. In addition, we highlight the status of clinical treatment for coagulation disorder and nephropathy caused by each other, indicating guidance for the formulation of therapeutic strategies or drug development.

Real-life effects, complications, and outcomes in 39 critically ill neonates receiving continuous kidney replacement therapy

BACKGROUND

Continuous kidney replacement therapy (CKRT) has been expanded from simple kidney replacement therapy to the field of critical illness in children. However, CKRT is rarely used in critically ill neonates in the neonatal intensive care unit (NICU). This study aimed to describe patients' clinical characteristics at admission and CKRT initiation, CKRT effects, short-term outcomes, and predictors of death in critically ill neonates.

METHODS

A 7-year single-center retrospective study in a tertiary NICU.

RESULTS

Thirty-nine critically ill neonates received CKRT between May 2015 and April 2022 with a mortality rate of 35.9%. The most common primary diagnosis was neonatal sepsis in 15 cases (38.5%). Continuous veno-venous hemodiafiltration and continuous veno-venous hemofiltration were applied in 43.6% and 56.4% of neonates, respectively. The duration of CKRT was 44 (18, 72) h. Thirty-one patients (79.5%) had complications due to CKRT-related adverse events, and the most common complication was thrombocytopenia. Approximately 12 h after the CKRT initiation, urine volume, mean arterial pressure, and pH were increased, and serum creatinine, blood urea nitrogen, and blood lactate were decreased. In the multivariate logistic regression analysis, neonatal critical illness score [odds ratio 0.886 (0.786 ~ 0.998), P = 0.046] was an independent risk factor for death in critically ill neonates who received CKRT.

CONCLUSIONS

CKRT can be an effective and feasible technique in critically ill neonates, but the overall mortality and CKRT-related complications are relatively high. Furthermore, the probability of death is greater among neonates with greater severity of illness at CKRT initiation. A higher resolution version of the Graphical abstract is available as Supplementary information.

Advances in Enhancing Hemocompatibility of Hemodialysis Hollow-Fiber Membranes

Hemodialysis, the most common modality of renal replacement therapy, is critically required to remove uremic toxins from the blood of patients with end-stage kidney disease. However, the chronic inflammation, oxidative stress as well as thrombosis induced by the long-term contact of hemoincompatible hollow-fiber membranes (HFMs) contribute to the increase in cardiovascular diseases and mortality in this patient population. This review first retrospectively analyzes the current clinical and laboratory research progress in improving the hemocompatibility of HFMs. Details on different HFMs currently in clinical use and their design are described. Subsequently, we elaborate on the adverse interactions between blood and HFMs, involving protein adsorption, platelet adhesion and activation, and the activation of immune and coagulation systems, and the focus is on how to improve the hemocompatibility of HFMs in these aspects. Finally, challenges and future perspectives for improving the hemocompatibility of HFMs are also discussed to promote the development and clinical application of new hemocompatible HFMs.

Graphical Abstract

Assessment of the impact of anemia on hematological parameters among hemodialysis patients with chronic kidney disease

Anemia is a common consequence of chronic kidney disease (CKD) that is linked to a decrease in patients' quality of life, a rise in morbidity and mortality, and an acceleration in CKD progression. This study aimed to investigate the hematological profile of chronic renal patients undergoing hemodialysis and to correlate the same with anemia. Fifty (54% males and 46% females) with ages ranging from 18-76 years of patients with CKD and on regular maintenance hemodialysis not less than three months at the Iraqi center for dialysis in Baghdad teaching hospital, and 30 healthy adults were recruited into the study. Hemoglobin concentration, red cell count, white blood cell count, platelet count, ESR, CRP and HCV were assessed for the subjects and controls. Results were analyzed using a t-test independent, and the data were retrieved from the laboratory information system in the hospital. Red blood cell count was reduced in nearly all (96%) of the study patients, while ESR was elevated in (98%) and CRP was elevated in (95%). All patients suffered anemia in HD patients. Most of the patients' WBCs and platelet counts were normal. Anti-HCV antibodies were positive in 15 (30%) of these patients, with non-significant differences in both genders. The study concludes that anemia is a significant comorbidity in hemodialysis patients, with several factors contributing to it, and thorough workup and successful treatment of anemia are essential in this group of patients. Keywords: Anemia; Hematological profile; Hemodialysis; Hepatitis; chronic kidney disease

Adult-Onset Immunoglobulin A Vasculitis Following Hemodialysis Treatment: An Unusual Presentation

Immunoglobulin A (IgA) vasculitis, formerly known as Henoch-Schönlein purpura (HSP), is a small vessel vasculitis due to perivascular deposition of dominant IgA immune complexes. It classically presents with symptoms such as palpable purpura, abdominal pain, kidney dysfunction, and joint pain. It most commonly affects children less than 10 years old. We present the case of a 53-year-old male who developed purpuric rashes a few hours after receiving hemodialysis. Initially, the lesions were localized to his legs and buttocks. They continued to spread over his back, abdomen, and arms. He experienced joint pain in both of his wrists, as well as abdominal tenderness. Labs revealed elevated IgA levels: 422 mg/dL (normal: 61 - 356 mg/dL). C3, C4, and antinuclear antibody (ANA) levels were within normal limits. Oral prednisone and topical diphenhydramine resulted in significant improvement in his symptoms. To our knowledge, there are only five reports documenting the occurrence of HSP in adults undergoing hemodialysis. Although HSP is a rare finding in adults, recognition of the disease is important as it can cause significant morbidity and mortality if left untreated.

Effect of dialysis modalities on risk of hospitalization for gastrointestinal bleeding

Dialysis patients are at risk of both thromboembolic and bleeding events, while thromboembolism prevention and treatment may confer a risk of major bleeding. Gastrointestinal (GI) bleeding is a great concern which can result in high subsequent mortality rates. Our object was to clarify whether hemodialysis (HD) and peritoneal dialysis (PD) confer different incidence of GI bleeding, and further assist individualized decision-making on dialysis modalities. We conducted a population-based retrospective cohort study which included all incident dialysis patients above 18 years old derived from the National Health Insurance database from 1998 to 2013 in Taiwan. 6296 matched pairs of HD and PD patients were identified. A propensity score matching method was used to minimize the selection bias. The adjusted hazard ratio for GI bleeding was 1.13 times higher in the HD group than in the PD group, and data from the unmatched cohort and the stratified analysis led to similar results. Among subgroup analysis, we found that the use of anticoagulants will induce a much higher incidence of GI bleeding in HD patients as compared to in PD patients. We concluded that PD is associated with a lower GI bleeding risk than HD, and is especially preferred when anticoagulation is needed.

The relationship between platelet distribution width and new-onset cardiovascular disease events in patients with peritoneal dialysis

Objectives

The global mortality rate from chronic kidney disease (CKD) has increased over the past two decades. Typically, peritoneal dialysis (PD) remains a useful alternative treatment for end-stage renal disease. Cardiovascular disease (CVD) is the main complication in PD patients. In terms of prognosis, it is reported that platelet distribution width (PDW) can predict adverse CVD events. However, the relationship between PDW and new-onset CVD in PD patients is not clear. This study aimed to explore the relationship between PDW and new-onset CVD in PD patients.

Methods

This was a retrospective cohort study, from 4 July 2005 to 31 December 2019, and a total of 1557 patients were recruited. PDW was respectively categorized into two groups: PDW ≤13.2 fL and PDW >13.2 fL. The primary outcome was a new-onset CVD event. Cox proportional hazards models were performed to assess the hazard ratio (HR). Receiver-operating characteristic (ROC) curves were applied to evaluate the predictive accuracy of the PDW on CVD events.

Results

During follow-up, 114 new-onset CVD events were recorded. Cox proportional hazards models showed a higher risk of CVD events in patients with high PDW (HR = 1.862 95%CI 1.205–2.877, p = 0.005). Kaplan–Meier cumulative incidence curves showed the risk of the first occurrence of CVD events was greater in the high PDW group (p = 0.006).

Conclusions

High PDW is associated with new-onset cardiovascular disease events in PD patients.

Renal Klotho safeguards platelet lifespan in advanced chronic kidney disease through restraining Bcl-xL ubiquitination and degradation

BACKGROUND

Thrombosis and hemorrhage as two opposite pathologies are prevalent within the chronic kidney disease (CKD) population. Platelet homeostasis, which positions centrally in their pathogenesis, varies among the CKD population, while the underlying mechanism is poorly understood.

OBJECTIVE

To investigate the change character and mechanism of platelet homeostasis in CKD and its association with renal Klotho deficiency.

METHODS

The change character of platelet homeostasis and its association with renal Klotho deficiency were determined based on a cohort study as well as CKD mice and Klotho-deficient mice with CKD. The effects on thrombopoiesis and platelet lifespan were examined by flow cytometry and platelet transfer. The underlying mechanism was explored by proteomics, flow cytometry, western blot, and immunoprecipitation.

RESULTS

We show that platelet count declines both in patient and mouse models with advanced CKD (Adv-CKD) and is positively associated with circulating Klotho levels. Mechanistically, we identify that ubiquitin ligase UBE2O governs Bcl-xL ubiquitination and degradation in platelets, whereas Adv-CKD-induced oxidative stress in platelets stimulates p38MAPK to promote Bcl-xL phosphorylation, which facilitates UBE2O binding to Bcl-xL and subsequent Bcl-xL degradation. Consequently, platelet lifespan is shortened in Adv-CKD, culminating in platelet count decline. However, kidney-secreted soluble Klotho protein restricts oxidative stress in platelets, thereby preserving Bcl-xL expression and platelet lifespan.

CONCLUSIONS

Our findings uncover the mechanism of platelet count decline in Adv-CKD and identify renal Klotho as a long-range regulator of platelet lifespan, which not only provide a molecular mechanism underlying CKD-associated thrombocytopenia and hemorrhage but also offer a promising therapy choice.

The use of a low-flux hemo-dialyzer is associated with impaired platelet aggregation in patients undergoing chronic hemodialysis

In patients with chronic hemodialysis (HD), both abnormal thrombotic and bleeding events are commonly observed. Uremic platelet dysfunction is one of the important attributing factors. Moreover, HD may also result in aggregation dysfunction of platelets during the therapeutic procedure. However, how the HD process affects platelet and coagulation function is unknown and dialyzer membrane flux could have an impact on it. We aimed to compare the impacts of low-flux and high-flux HD on the platelet function of patients undergoing chronic HD. This was a cross-sectional study conducted in the HD unit of E-Da hospital in Taiwan. A total of 78 patients with maintenance HD three times per week for more than one year, including 40 with high- and 38 with low-flux hemodialysis, were recruited. Their platelet functions were evaluated using an in vitro platelet function analyzer (PFA-100) before and after the HD session. Of the 78 patients undergoing HD, 60 (76%) had prolonged pre-dialysis collagen/epinephrine (CEPI) and collagen/adenosine diphosphate closure times. Those receiving low-flux dialyzer had a significant increase in CEPI closure time (pre-dialysis 212.3 ± 62.1 seconds. post-dialysis 241.5 ± 64.3 seconds, P = .01), but not collagen/adenosine diphosphate closure time, after HD. After adjusting confounding factors, only the low-flux dialyzer demonstrated an independent association with the prolonged CEPI closure time after HD therapy (odds ratio = 23.31, 95% CI: 1.94-280.61, P = .01). We observed that impaired platelet aggregation is prevalent in patients undergoing chronic HD. Therefore, the use of low-flux dialyzers may further worsen platelet aggregation after dialysis. Patients with uremic bleeding diathesis should take precautions. We suggest that further studies using flow cytometry should be conducted to explore the mechanism of dialysis flux and platelet activity during HD.

Impact of Hydrophilic Modification of Synthetic Dialysis Membranes on Hemocompatibility and Performance

The dialyzer is the core element in the hemodialysis treatment of patients with end-stage kidney disease (ESKD). During hemodialysis treatment, the dialyzer replaces the function of the kidney by removing small and middle-molecular weight uremic toxins, while retaining essential proteins. Meanwhile, a dialyzer should have the best possible hemocompatibility profile as the perpetuated contact of blood with artificial surfaces triggers complement activation, coagulation and immune cell activation, and even low-level activation repeated chronically over years may lead to undesired effects. During hemodialysis, the adsorption of plasma proteins to the dialyzer membrane leads to a formation of a secondary membrane, which can compromise both the uremic toxin removal and hemocompatibility of the dialyzer. Hydrophilic modifications of novel dialysis membranes have been shown to reduce protein adsorption, leading to better hemocompatibility profile and performance stability during dialysis treatments. This review article focuses on the importance of performance and hemocompatibility of dialysis membranes for the treatment of dialysis patients and summarizes recent studies on the impact of protein adsorption and hydrophilic modifications of membranes on these two core elements of a dialyzer.

Cyclical depressurization degranulates platelets in an agonist-free mechanism of platelet activation

Activation of circulating platelets by receptor binding and subsequent coagulation events are defined by a well characterized physiological response. However, the growing prevalence of chronic kidney disease (CKD) and implication of platelet-released factors in worsening cardiovascular outcomes with hemodialysis warrant further investigation into the mechanobiology of platelet degranulation. The significant drops in pressure caused by high friction across the hemodialysis flow circuit present an overlooked platelet stimulant not involving immobilization as a driver for cytoskeletal rearrangement. In this study, platelets from healthy and dialysis (pre- and post-treatment) donors were cyclically depressurized in static suspension to measure changes in physiology by integrin αIIbβ3 activation and surface P-selectin expression. The progressive increase in CD62P with no changes in PAC1 over pressure-cycling duration regardless of uremia signifies that hydrostatic depressurization involves a novel agonist-free mechanism leading to platelet degranulation as a unique case in which CD62P and PAC1 do not interchangeably indicate platelet activation. Subsequent stimulation using ADP further suggests that sustained depressurization regimens desensitize integrin αIIbβ3 activation. Variability in platelet response caused by uremia and CKD are observed by elevated baseline PAC1 in pre-dialysis samples, PAC1 retention after ADP exposure, and maximum CD62P with ADP independent of pressure. Theory for hydrostatic pressure-induced degranulation circumventing integrin-initiated signal transduction is here presented based on the Starling Equation.

Plasma C4 level was associated with mortality, cardiovascular and cerebrovascular complications in hemodialysis patients

BACKGROUND

Patients on maintenance hemodialysis (HD) exhibit a high risk of death, cardiovascular and cerebrovascular diseases (CCDs). Previous studies indicated complement activation associated with the increased risk of cardiovascular diseases in HD patients. This study aimed to explore whether the critical complement factors were associated with the adverse outcomes in HD patients.

METHODS

A total of 108 HD patients were included and followed up for 52 months. The baseline clinical characteristics and plasma C3c, C1q, CFH, CFB, C4, MAC, C5a, C3a and MBL were measured. The three endpoints were death, cardiovascular and cerebrovascular events (CCEs) and the composition of them. Univariate and multivariate Cox regression identified factors associated with the three endpoints respectively. X-tile analyses determined the optimal cut-off values for high risks. Restricted cubic spline plots illustrated the dose-response relationships. Correlations between the complement factors and risk factors for CCDs were analyzed.

RESULTS

Baseline plasma C4 was finally selected by univariate and multivariate Cox regression analyses for three endpoints, including all-cause mortality, CCEs and the composition of them. When baseline plasma C4 exceeded 0.47 (P = 0.001) or 0.44 (P = 0.018) g/L respectively, the risks for death or achieving the composite endpoint enhanced significantly. The relationships of C4 and HR for the three endpoints showed a positive linear trend. Plasma C4 had prominent correlations with blood TG (r = 0.62, P < 0.001) and HDL (r = -0.38, P < 0.001).

CONCLUSIONS

A higher baseline plasma C4 level was significantly associated with the future incidence of decease, CCEs and either of them. Plasma C4 level correlated with blood TG and HDL.

Immune System Dysfunction and Inflammation in Hemodialysis Patients: Two Sides of the Same Coin

Biocompatibility in hemodialysis (HD) has considerably improved in recent decades, but remains an open issue to be solved, appearing essential to reduce systemic inflammation and enhance patients’ clinical outcomes. Clotting prevention, reduction in complement and leukocyte activation, and improvement of antioxidant effect represent the main goals. This review aims to analyze the different pathways involved in HD patients, leading to immune system dysfunction and inflammation. In particular, we mostly review the evidence about thrombogenicity, which probably represents the most important characteristic of bio-incompatibility. Platelet activation is one of the first steps occurring in HD patients, determining several events causing chronic sub-clinical inflammation and immune dysfunction involvement. Moreover, oxidative stress processes, resulting from a loss of balance between pro-oxidant factors and antioxidant mechanisms, have been described, highlighting the link with inflammation. We updated both innate and acquired immune system dysfunctions and their close link with uremic toxins occurring in HD patients, with several consequences leading to increased mortality. The elucidation of the role of immune dysfunction and inflammation in HD patients would enhance not only the understanding of disease physiopathology, but also has the potential to provide new insights into the development of therapeutic strategies.

Renal replacement therapy and concurrent fluconazole therapy increase linezolid-related thrombocytopenia among adult patients

Linezolid has been reported to be associated with thrombocytopenia. However, limited information is available on susceptibility to thrombocytopenia after linezolid usage. We aimed to investigate the risk factors for linezolid-associated thrombocytopenia (LAT). We conducted a retrospective cohort study of patients aged ≥ 18 years who received linezolid for ≥ 5 d during hospitalization in 2019. Information was extracted from electronic medical records. Thrombocytopenia was defined as a platelet count of < 100 × 10⁹/L or a reduction from baseline ≥ 25%. Binary logistic regression and survival analyses were used to evaluate the risk factors for LAT. A total of 98 patients were enrolled. Thrombocytopenia occurred in 53.1% patients, with a median of 9 d after initiation of linezolid. There was no significant difference in the mortality or proportion of platelet transfusions between patients with and without thrombocytopenia. A higher risk of LAT was found in patients who received renal replacement therapy (RRT) (OR 4.8 [1.4–16.4]), or concurrent fluconazole (OR 3.5 [1.2–9.8]). Patients who received RRT (8 vs. 15 d) or concurrent fluconazole (11 vs. 15 d) had a shorter median time to develop thrombocytopenia. Those who simultaneously received RRT and fluconazole had the shortest median of time (6.5 d) and the highest risk of developing thrombocytopenia (87.5%).

Association of platelet count with all-cause mortality from acute respiratory distress syndrome: A cohort study

Background

The purpose of this study was to investigate whether platelet count was associated with mortality in acute respiratory distress syndrome (ARDS) patients.

Methods

We analyzed patients with ARDS from Multi‐parameter Intelligent Monitoring in Intensive Care Database III (MIMIC‐III). Platelet count was measured at the time of intensive care unit (ICU) admission. The cox proportional hazard model and subgroup analysis were used to determine the relationship between the platelet count and mortality of ARDS, as well as the consistency of its association. The primary outcome of this study was 365‐day mortality from the date of ICU admission.

Result

This study enrolled a total of 395 critically ill patients with ARDS. After adjustment for age, gender and ethnicity, the multivariate cox regression model showed that the hazard ratios (HRs) (95% confidence intervals [CIs]) of platelet count <192 × 10⁹/L and >296 × 10⁹/L were 2.08 (1.43, 3.04) and 1.35 (0.91, 2.01), respectively, compared with the reference (192–296 ×10⁹/L). After adjusting for confounding factors, lower platelet count (<192 × 10⁹/L) was associated with increased mortality (adjusted HR, 1.71; 95% CI 1.06–2.76, p = 0.0284). However, there was no similar trend in the 30‐day (adjusted HR,1.02; 95% CI 0.54–1.94) or 90‐day (adjusted HR, 1.65; 95% CI 0.94–2.89) mortality. In the subgroup analysis, lower platelet count showed significant interactions with specific populations (p interaction = 0.0413), especially in patients with atrial fibrillation.

Conclusion

Taken together, our analysis showed that platelet count is an independent predictor of mortality in critically ill patients with ARDS.

Platelet Abnormalities in CKD and Their Implications for Antiplatelet Therapy

Patients with CKD display a significantly higher risk of cardiovascular and thromboembolic complications, with around half of patients with advanced CKD ultimately dying of cardiovascular disease. Paradoxically, these patients also have a higher risk of hemorrhages, greatly complicating patient therapy. Platelets are central to hemostasis, and altered platelet function resulting in either platelet hyper- or hyporeactivity may contribute to thrombotic or hemorrhagic complications. Different molecular changes have been identified that may underlie altered platelet activity and hemostasis in CKD. In this study, we summarize the knowledge on CKD-induced aberrations in hemostasis, with a special focus on platelet abnormalities. We also discuss how prominent alterations in vascular integrity, coagulation, and red blood cell count in CKD may contribute to altered hemostasis in these patients who are high risk. Furthermore, with patients with CKD commonly receiving antiplatelet therapy to prevent secondary atherothrombotic complications, we discuss antiplatelet treatment strategies and their risk versus benefit in terms of thrombosis prevention, bleeding, and clinical outcome depending on CKD stage. This reveals a careful consideration of benefits versus risks of antiplatelet therapy in patients with CKD, balancing thrombotic versus bleeding risk. Nonetheless, despite antiplatelet therapy, patients with CKD remain at high cardiovascular risk. Thus, deep insights into altered platelet activity in CKD and underlying mechanisms are important for the optimization and development of current and novel antiplatelet treatment strategies, specifically tailored to these patients who are high risk. Ultimately, this review underlines the importance of a closer investigation of altered platelet function, hemostasis, and antiplatelet therapy in patients with CKD.

Environmental microplastic and nanoplastic: Exposure routes and effects on coagulation and the cardiovascular system

Plastic pollution has been a growing concern in recent decades due to the proliferation and ease of manufacturing of single use plastic products and inadequate waste and recycling management. Microplastic, and even smaller nanoplastic, particles are persistent pollutants in aquatic and terrestrial systems and are the subject of active and urgent research. This review will explore the current research on how exposure to plastic particles occurs and the risks associated from different exposure routes: ingestion, inhalation, and dermal exposure. The effects of microplastics on the cardiovascular system are of particular importance due to its sensitivity and ability to transport particles to other organ systems. The effects of microplastics and nanoplastics on the heart, platelet aggregation, and thrombus formation will all be explored with focus on how the particle characteristics modulate their effect. Plastic particle interactions are highly dependent on both their size and their surface chemistry and interesting research is being done with the interaction of particle characteristics and effect on thrombosis and the cardiovascular system. There is significant uncertainty surrounding some of the findings in this field as research in this area is still maturing. There are undoubtedly more physiological consequences than we are currently aware of resulting from environmental plastic exposure and more studies need to be conducted to reveal the full extent of pathologies caused by the various routes of microplastic exposure, with particular emphasis on longitudinal exposure effects. Further research will allow us to recognize the full extent of physiological impact and begin developing viable solutions to reduce plastic pollution and potentially design interventions to mitigate in-vivo plastic effects following significant or prolonged exposure.

Data on the in vitro elution of substances from three types of polysulfone membrane dialyzers as well as a non-polysulfone cellulose triacetate membrane dialyzer evaluated using ultraviolet absorption

We evaluated the influences of the priming process (washing with saline), saline circulation conditions, and saline incubation on the in vitro elution of substances from three types of polysulfone (PSu) membrane dialyzers sterilized using gamma irradiation [NV-15X (Toray Industries, Inc.)], autoclaving [RENAK-PS1.6 (Kawasumi Laboratories, Inc.)], or in-line steam [FX-140J (Fresenius Medical Care)] methods as well as a non-PSu cellulose triacetate (CTA) membrane dialyzer [FB-150U(NIPRO)]. The effect of priming was evaluated by circulating 1000 mL of saline through the dialyzers at a rate of 100 mL/min and measuring the elution level of the substances by determining their ultraviolet (UV) absorption at 220 nm using spectrophotometry. All the tested dialyzers showed that the elution of the substances decreased as per the order of sample collection. Primed dialyzers were used in the subsequent experiments. Circulating saline through the primed membrane dialyzers at a flow rate of 100 mL/min caused time-dependent elution of substances from all the tested dialyzers; increasing the flow rate to 200 mL/min did not have a significant effect on the time-dependence or elution amount at each time point (0–8 h). The elution was also evaluated after incubating the membrane dialyzers with saline for 24 h. A co-submitted article (Sato et al., 2021) detailed the preparation of the identical experimental circuits, as well as the influences of saline washing, saline circulation conditions, and saline incubation on the elution of the hydrophilic agent polyvinylpyrrolidone (PVP) from each dialyzer using the Müller method, which can enable specific detection of PVP (Müller, 1968). The relative elution levels of PVP among the dialyzers and the experimental conditions were different from those of substances determined using UV (220 nm) absorption. Our data might be used for further development of experiments for identifying non-PVP substances eluted from dialyzers by providing information regarding the conditions of the elutions and types of dialyzers from which they are eluted.

Recent advances in dialysis membranes

PURPOSE OF REVIEW

Improvement in hemodialysis treatment and membrane technology are focused on two aims: the first one is to achieve a better control of circulating uremic solutes by enhancing removal capacity and by broadening molecular weight spectrum of solutes cleared; the second one is to prevent inflammation by improving hemocompatibility of the global dialysis system.

RECENT FINDINGS

Despite impressive progresses in polymers chemistry few hazards are still remaining associated with leaching or sensitization to polymer additives. Research has focused on developing more stable polymers by means of additives or processes aiming to minimize such risks. Membrane engineering manufacturing with support of nanocontrolled spinning technology has opened up membrane to middle and large molecular weight substances, while preserving albumin losses. Combination of diffusive and enhanced convective fluxes in the same hemodialyzer module, namely hemodiafiltration, provides today the highest solute removal capacity over a broad spectrum of solutes.

SUMMARY

Dialysis membrane is a crucial component of the hemodialysis system to optimize solute removal efficacy and to minimize blood membrane biological reactions. Hemodialyzer is much more than a membrane. Dialysis membrane and hemodialyzer choice are parts of a treatment chain that should be operated in optimized conditions and adjusted to patient needs and tolerance, to improve patient outcomes.

Significance of mild thrombocytopenia in maintenance hemodialysis patients; a retrospective cohort study

Platelet activation in the hemodialysis (HD) circuit often causes thrombocytopenia. However, its clinical and pathophysiological significance has rarely been explored. Herein, we investigated the predictive value of thrombocytopenia for cardiovascular events (CVE) in maintenance HD patients and attempted to explore its mechanistic background considering recent knowledge of platelet dynamics. We conducted a retrospective cohort study on HD patients with the composite primary endpoint of predicting CVE, i.e., myocardial infarction, ischemic stroke, and cardiovascular death. Baseline clinical data were analyzed and explored. Multivariate Cox regression analysis showed that platelet decrease was independently associated with CVE. Thrombocytopenia was correlated with the disuse of antiplatelet therapy (APT) and macrocytosis. These findings are possibly associated with platelet activation and senescent hematopoiesis. The prognostic significance of thrombocytopenia was more prominent in patients undergoing APT, implying the presence of APT-resistant platelets in such patients. To fully explain these results, we hypothesized that HD-activated platelets induce the biological aging of hematopoiesis, which is presumably extramedullary in the lung, where activated platelets could deliver massive amounts of inflammatory cytokines and reactive oxidative species. This results in the production of qualitatively altered and hyper-reactive platelets, a process that could form a vicious cycle that induces CVE-associated thrombocytopenia. Further investigations focusing on the dynamics of the biological aging of platelets in HD patients are warranted.

Influences of the priming procedure and saline circulation conditions on polyvinylpyrrolidone in vitro elution from polysulfone membrane dialyzers

In hemodialysis (HD), the patient's blood is purified via circulation in an extracorporeal circuit containing a dialyzer. In the manufacturing process of polysulfone (PSu) membrane dialyzers, the membranes are hydrophilized via the addition of the hydrophilic agent polyvinylpyrrolidone (PVP) to increase their hydraulic permeability. The elution of PVP from the membrane reduces the membrane's hydraulic permeability, and the eluted PVP could cause adverse effects in the human body. Therefore, it is important to identify the factors that induce PVP elution from PSu dialyzer membranes to improve the efficiency and safety of HD. In the present study, experimental circuits connecting each of the three types of PSu membrane dialyzers that had been sterilized, using gamma irradiation, autoclaving, or in-line steam methods, were prepared. After the dialyzers were primed, saline was circulated in the circuits at a flow rate of 100 mL/min or 200 mL/min. At 0, 2, 4, 6, and 8 h after circulation was initiated, the amount of PVP eluted from the PSu membranes in vitro was determined. In this experimental setting, longer the circulation duration, greater the amount of PVP eluted from the PSu membranes of the tested dialyzers; however, the flow rate did not influence the in vitro elution of PVP. Furthermore, the immersion of the dialyzer membranes in saline for 24 h strongly facilitated the in vitro elution of PVP. In sum, these results suggest that the duration of PSu membrane incubation in saline is a determinant of the level of PVP elution from the PSu membrane dialyzers.

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The flow rate did not influence the in vitro PVP elution from PSu membrane dialyzers.

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The time of PSu membrane incubation in saline is a determinant of PVP elution level.

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Substances other than PVP are eluted from PSu membrane dialyzers.

The spleen size in patients undergoing hemodialysis

Introduction:

Inflammation promotes the progression of chronic renal failure, and the start of dialysis worsens inflammation. The enlargement of the spleen is associated with inflammation, and patients on hemodialysis may show a large spleen. The aim of the present study was to compare the spleen size of patients undergoing hemodialysis versus controls to update this thread.

Methods:

Controls and patients were eligible to participate in the study provided they were negative for serological markers of hepatitis B and C viruses and HIV, if they had no lymphoproliferative disorder, and if they were at least 18 years of age. Age, sex, and the duration of dialysis were recorded. Laboratory variables (hemoglobin, hematological cell count, serum creatinine) and the underlying cause of end-stage renal disease were analyzed. The spleen sizes of the patients were divided into tertiles.

Results:

The 75 controls and 168 patients selected were sex-matched. The patients were older, had larger spleens and lower platelet counts than controls. The relationship between spleen size and age in the controls and patients was quite similar. The patients in the first tertile of spleen size compared with those in the third were older and had a higher platelet counts. The underlying disease and dialysis vintage had no effect on spleen size.

Discussion:

The patients had larger spleens and a greater range of spleen sizes than the controls. In patients, the association between larger and smaller spleen with lower and higher platelet counts, respectively, sparked the speculation of occurrence of hypersplenism and hyposplenism.

The Association of Platelet Decrease Following Continuous Renal Replacement Therapy Initiation and Increased Rates of Secondary Infections

OBJECTIVES

Thrombocytopenia is common in critically ill patients treated with continuous renal replacement therapy and decreases in platelets following continuous renal replacement therapy initiation have been associated with increased mortality. Platelets play a role in innate and adaptive immunity, making it plausible that decreases in platelets following continuous renal replacement therapy initiation predispose patients to development of infection. Our objective was to determine if greater decreases in platelets following continuous renal replacement therapy correlate with increased rates of secondary infection.

DESIGN

Retrospectivecohort analysis.

SETTING

This study uses a continuous renal replacement therapy database from Mayo Clinic (Rochester, MN), a tertiary academic center.

PARTICIPANTS

Adult patients who survived until ICU discharge and were on continuous renal replacement therapy for less than 30 days were included. A subgroup analysis was also performed in patients with thrombocytopenia (platelets < 100 × 103/µL) at continuous renal replacement therapy initiation.

MEASUREMENTS AND MAIN RESULTS

The primary predictor variable was a decrease in platelets from precontinuous renal replacement therapy levels of greater than 40% or less than or equal to 40%, although multiple cut points were analyzed. The primary outcome was infection after ICU discharge, and secondary endpoints included post-ICU septic shock and post-ICU mortality. Univariable, multivariable, and propensity-adjusted analyses were used to determine associations between the predictor variable and the outcomes.

RESULTS

Among 797 eligible patients, 253 had thrombocytopenia at continuous renal replacement therapy initiation. A greater than 40% decrease in platelets after continuous renal replacement therapy initiation was associated in the multivariable-adjusted models with increased odds of post-ICU infection in the full cohort (odds ratio, 1.49; CI, 1.02-2.16) and in the thrombocytopenia cohort (odds ratio, 2.63; CI, 1.35-5.15) cohorts.

CONCLUSIONS

Platelet count drop by greater than 40% following continuous renal replacement therapy initiation is associated with an increased risk of secondary infection, particularly in patients with thrombocytopenia at the time of continuous renal replacement therapy initiation. Further research is needed to evaluate the impact of both continuous renal replacement therapy and platelet loss on subsequent infection risk.

Biocompatibility Parameters with Standard and Increased Dose of Citrate in Hemodialysis-A Randomized Trial

Background: The dose of citrate needed in regional citrate anticoagulation (RCA) to achieve optimal biocompatibility is unknown. We performed a randomized trial comparing two doses (ACTRN12613001340729). Methods: In 30 patients a single hemodialysis with either standard (2.7 mmol/L) or increased dose of citrate (4 mmol/L) was performed. C5a-desArg, myeloperoxidase (MPO), thrombin-antithrombin complex (TAT), and platelet factor 4 (PF4) were measured and the inner surface of the dialyzer fibers was evaluated with scanning electron microscopy (SEM). Results: A good separation of anticoagulation effect was achieved (post-filter ionized calcium 0.20 vs. 0.31 mmol/L, p < 0.05). There was no effect of citrate dose on any of the biocompatibility parameters; transient and parallel increase in PF4 after 30 min and parallel increase in TAT after 4 h were observed. There were no visually detected clotting problems within the circuit and no significant hypocalcemia in either group. SEM clotting score was excellent and comparable in both groups (p = 0.59). Conclusions: Given the excellent results in both groups, absence of between group differences and inability of the increased dose of citrate to completely blunt the small residual increase in PF4 and TAT, we conclude that the standard dose of citrate seems sufficient in RCA for chronic hemodialysis.

Thrombocytopenia Induced by Polysulfone Dialysis Membranes

Patient: Male, 82-year-old

Final Diagnosis: End stage renal disease • thrombocytopenia • co-existing disea

Symptoms: Fatigue • melena • weakness

Medication: —

Clinical Procedure: —

Specialty: Nephrology

Contact Activation Inhibitor, AB023, in Heparin-Free Hemodialysis: Results of a Randomized Phase 2 Clinical Trial

End-stage renal disease (ESRD) patients on chronic hemodialysis have repeated blood exposure to artificial surfaces that can trigger clot formation within the hemodialysis circuit. Dialyzer clotting can lead to anemia despite erythropoietin and iron supplementation. Unfractionated heparin prevents clotting during hemodialysis, but it is not tolerated by all patients. Although heparin-free dialysis is performed, intradialytic blood entrapment can be problematic. To address this issue, we performed a randomized, double-blind, phase 2 study comparing AB023, a unique antibody that binds factor (F) XI and blocks its activation by factor XIIa but not by thrombin, to placebo in 24 patients with ESRD undergoing heparin-free hemodialysis (www.clinicaltrials.gov #NCT03612856). Patients were randomized to receive a single pre-dialysis dose of AB023 (0.25 or 0.5 mg/kg) or placebo in a 2:1 ratio and safety and preliminary efficacy were compared to placebo and to observations made prior to dosing within each treatment arm. AB023 administration was not associated with impaired hemostasis or other drug-related adverse events. Occlusive events requiring hemodialysis circuit exchange were less frequent and levels of thrombin-antithrombin complexes and C-reactive protein were lower after AB023 administration compared with data collected prior to dosing. AB023 also reduced potassium and iron entrapment in the dialyzers, consistent with less blood accumulation within the dialyzers. We conclude that despite the small sample size, inhibition of contact activation-induced coagulation with AB023 was well tolerated and reduced clotting within the dialyzer.

Polyvinylpyrrolidone in hemodialysis membranes: Impact on platelet loss during hemodialysis

INTRODUCTION

Hydrophilic modification with polyvinylpyrrolidone (PVP) increases the biocompatibility profile of synthetic dialysis membranes. However, PVP may be eluted into the patient's blood, which has been discussed as a possible cause for adverse reactions rarely occurring with synthetic membranes. We investigated the content of PVP and its elution from the blood-side surface from commercially available dialyzers, including the novel FX CorAL, with PVP-enriched and α-tocopherol-stabilized membrane, and link the results to the level of platelet loss during dialysis as a maker of biocompatibility.

METHODS

Six synthetic, PVP containing, dialyzers (FX CorAL, FX CorDiax [Fresenius Medical Care]; Polyflux, THERANOVA [Baxter]; ELISIO [Nipro]; xevonta [B. Braun]) were investigated in the present study. The content of PVP on blood-side surface was determined with X-ray photoelectron spectroscopy (XPS). The amount of elutable PVP was measured photometrically after 5 h recirculation. The level of platelet loss was evaluated in an ex vivo recirculation model with human blood.

FINDINGS

Highest PVP content on the blood-side surface was found for the polysulfone-based FX CorAL (26.3%), while the polyethersulfone-based THERANOVA (15.6%) had the lowest PVP content. Elution of PVP was highest for the autoclave steam-sterilized THERANOVA (9.1 mg/1.6 m² dialyzer) and Polyflux (9.0 mg/1.6 m² dialyzer), while the lowest PVP elution was found for the INLINE steam sterilized FX CorAL and FX CorDiax (<0.5 mg/1.6 m² dialyzer, for both). Highest platelet loss was found for xevonta (+164.4% compared to the reference) and the lowest for the FX CorAL (-225.2%) among the polysulfone-based dialyzers; among the polyethersulfone-based dialyzers, THERANOVA (+95.5%) had the highest and ELISIO (-52.1%) the lowest platelet loss.

DISCUSSION

Polyvinylpyrrolidone content and elution differ between commercially available dialyzers and were found to be linked to the membrane material and sterilization method. The amount of non-eluted PVP on the blood-side surface may be an important determinant for the biocompatibility of dialyzers.

Dialysis-related thrombocytopenia: a case report

Thrombocytopenia is frequently observed in hemodialysis patients, and its correct investigation and control remain a challenge. It is estimated that during the hemodialysis session there is a drop of up to 15% in the platelet count, with recovery after the end of treatment. This reduction in platelets is due to platelet adhesion and complement activation, regardless of the membrane material. Several studies with platelet surface markers demonstrate increased platelet activation and aggregation secondary to exposure to cardiopulmonary bypass. This case report describes a patient on hemodialysis who developed severe thrombocytopenia during hospitalization. Investigation and exclusion of the most common causes were carried out: heparin-related thrombocytopenia, adverse drug reaction, hypersplenism, and hematological diseases. Afterwards, the possibility of hemodialysis-related thrombocytopenia was raised, since the fall was accentuated during the sessions with partial recovery after the dialyzer change. Attention to the sterilization method and dialyzer reuse must be considered for correction. In the current case, reusing the dialyzer minimized the drop in platelet counts associated with hemodialysis.

Higher Prevalence of Concurrent Thrombocytopenia in Patients Receiving Continuous Renal Replacement Therapy in the Cardiac Intensive Care Unit

INTRODUCTION

Thrombocytopenia (TCP) is a common finding in patients receiving continuous renal replacement therapy (CRRT).

OBJECTIVE

The purpose of this study was to assess the nature of TCP in patients receiving CRRT.

METHODS

This is a single-center case-control observational study of 795 patients involving over 166,950 h of delivered CRRT at Johns Hopkins Hospital. Concurrent TCP in patients receiving CRRT was defined as a decrease in platelet count of ≥50% any time within 72 h of initiation of CRRT with strict exclusion criteria.

RESULTS

There was a higher incidence of TCP in the cardiac intensive care unit (CICU) (22.5%) compared to medical ICU (MICU) (13.1%). Using logistic regression, the odds of developing concurrent TCP in patients receiving CRRT was 2.46 (95% CI 1.32-3.57, p < 0.05) times higher in the CICU compared with the MICU. There was no difference in the incidence of severe or profound TCP or timing of acute TCP between the CICU and MICU.

CONCLUSION

Safe delivery of dialysis care in the ICU is paramount and creating awareness of potential risks such as concurrent TCP in patients receiving CRRT should be part of this care.

Registry on extracorporeal multiple organ support with the advanced organ support (ADVOS) system: 2-year interim analysis

The objective of this registry is to collect data on real-life treatment conditions for patients for whom multiple organ dialysis with Advanced Organ Support (ADVOS) albumin hemodialysis is indicated.This registry was performed under routine conditions and without any study-specific intervention, diagnostic procedures, or assessments. Data on clinical laboratory tests, health status, liver function, vital signs, and examinations were collected (DRKS-ID: DRKS00017068). Mortality rates 28 and 90 days after the first ADVOS treatment, adverse events and ADVOS treatment parameters, including treatment abortions, were documented.This analysis was performed 2 years after the first patient was included on January 18, 2017. As of February 20, 2019, 4 clinical sites in Germany participated and enrolled 118 patients with a median age of 60 (IQR: 45, 69) of whom 70 were male (59.3%). Patients had a median SOFA Score of 14 (IQR: 11, 16) and a predicted mortality of 80%. The median number of failing organs was 3 (IQR: 2, 4).Four hundred twenty nine ADVOS treatments sessions were performed with a median duration of 17 hours (IQR: 6, 23). A 5.8% of the ADVOS sessions (25 of 429) were aborted due to device related errors, while 14.5% (62 of 429) were stopped for other reasons. Seventy nine adverse events were documented, 13 of them device related (all clotting, and all recovered without sequels).A significant reduction in serum creatinine (1.5 vs 1.2 mg/dl), blood urea nitrogen (24 vs 17 mg/dl) and bilirubin (6.9 vs 6.5 mg/dl) was observed following the first ADVOS treatment session. Blood pH, bicarbonate (HCO3-) and base excess returned to the physiological range, while partial pressure of carbon dioxide (pCO2) remained unchanged. At the time of the analysis, 28- and 90-day mortality were 60% and 65%, respectively, compared to an expected ICU-mortality rate of 80%. SOFA score was an independent predictor for outcome in a multivariable logistic regression analysis.The reported data show a high quality and completion of all participating centers. Data interpretation must be cautious due to the small number of patients, and the nature of the registry, without a control group. However, the data presented here show an improvement of expected mortality rates. Minor clotting events similar to other dialysis therapies occurred during the treatments.

Updates on hemodialysis techniques with a common denominator: The personalization of the dialytic therapy

Hemodialysis (HD) is a life-saving therapy for patients with end-stage renal disease. In dialyzed patients, the prevalence of multi-morbidity is rising driven by various factors, such as the population aging, the incomplete correction of uremia, and the side effects of the dialysis therapy itself. Each dialyzed patient has their own specific clinical and biochemical problems. It is therefore unthinkable that the same dialysis procedure can be able to meet the needs of every patient on chronic dialysis. We have very sophisticated dialysis machines and different dialysis techniques and procedures beyond conventional HD, such as hemodiafiltration (HDF) with pre- and post-dilution, acetate-free biofiltration (AFB), hemofiltration (HF), and expanded HD. Each of these techniques has its own specific characteristics. To solve some intradialytic clinical issues, such as arterial hypotension and arrhythmias, we have biofeedback systems with automatic regulation of the blood volume, body temperature, arterial pressure, as well as potassium profiling techniques in the dialysis bath. New technical innovations, such as citrate-containing dialysate or heparin-coated membranes, could reduce the risk of bleeding. To better address to patient needs, the strengths and weaknesses of each of these systems must be well-known, in order to have a personalized dialysis prescription for each patient.

A case study of poly (aryl ether sulfone) hemodialysis membrane interactions with human blood: Molecular dynamics simulation and experimental analyses

Patients with end-stage renal diseases (ESRD) require specific health cares as the accumulation of toxins due to the lack of kidney functionality would affect their lives. However, the mortality rate is still high due to cardiovascular diseases, socks, etc. A majority of patients with chronic kidney disease (CKD) require hemodialysis services. Blood purifying membranes, as the main component of hemodialysis setups, however, still suffer from lack of optimum biocompatibility, which results in morbidity and mortality of hemodialysis service receiving patients. The goal of the present case study is to have an in-depth understanding of the current blood-hemodialysis membrane interactions occurring during hemodialysis sessions using poly (aryl ether sulfone)-poly (vinyl pyrrolidone) (PAES-PVP) membrane. Attenuated total reflectance-Fourier transmission infrared (ATR-FTIR) spectroscopy, Raman spectroscopy, and solid-state nuclear magnetic resonance (SSNMR) spectroscopy were used to assess the initial chemical structure of the PAES-PVP membrane along with the variations after with the infections with human blood. Furthermore, scanning electron microscopy (SEM) and Transition electron microscopy (TEM) were used to visualize the structural variation of the membrane, blood aggregations, and blood clots on the membrane surface. Besides, Molecular dynamics (MD) simulation was used to assess the interaction of PAES-PVP with major human blood proteins, in terms of interaction energy, which is a novel contribution to the area. The macromolecules (human serum albumin (HSA), human serum transferrin (TRF), and human fibrinogen (HFG)) were chosen from the plasma protein component. These protein structures were chosen based on their different molecular size. Three advanced spectroscopy techniques and two advanced visualization techniques were used for the assessment of the membranes. Spectroscopy studies revealed amine related peak displacement and intensity shifts as indices for attachment of biological species to the polymeric membrane surfaces. Raman peaks around 370, 798, and 1299 cm^-1, which experienced significant shifts that were related to carbon-nitrogen and sulfur-oxygen bonds due to protein adhesion. Visualization techniques illustrated blood protein fouling patterns and extracellular vesicles' presence in the pore structures into membranes. The findings highlight the importance of whole structure biocompatibility improvement, rather than only focusing on surface modifications of hemodialysis membranes. Molecular dynamics simulation assessment showed various interaction behaviors for different proteins suggesting molecular weight and active residues of the protein macromolecules play an important role in interacting with polymeric structure. FB had the highest interaction (4,274,749.07 kcal/mol) and binding (10,370.90 kcal/mol) energy with the PAES-PVP structure. TRF owned the lowest interaction energy with respect to its lower molecular weight and fewer active residue count.

In vitro blood compatibility evaluation method: incubating while rotating hemodialyzers filled with fresh human blood

One of the often-used methods for in vitro evaluation of the blood compatibility of hemodialysis membranes is the circulation of human blood through a miniaturized hemodialyzer. The use of a rather small amount of human blood in its evaluation is one advantage of this method. However, because it is manufactured by a different process than actual ones, a miniaturized hemodialyzer membrane cannot always preserve the properties of actual hemodialyzers. To address this problem, we established a new experimental method that uses a relatively small amount of human blood and actual dialyzers. In this method, a test hemodialyzer and a control hemodialyzer filled with human blood obtained from the same donor is slowly rotated to prevent spontaneous blood cell sedimentation for 4 h at 37 °C. By use of this method, we were able to compare blood compatibility between a polysulfone (PS) membrane and a vitamin E (VE)-bonded PS membrane in terms of their relative antithrombotic, antioxidative, and anti-inflammatory properties. Consistent with many previous reports, the results clearly showed that compared with the PS membrane, VE-bonded PS membrane is more blood compatible. These findings suggest that our method is applicable, at least to in vitro blood compatibility evaluation of PS type dialysis membranes.

A modified microchip-based flow chamber system for evaluating thrombogenicity in patients with thrombocytopenia

BACKGROUND

In the intensive care unit (ICU), patients with thrombocytopenia are at high risk for bleeding and should be assessed for their thrombogenic potential. However, the analytical conditions of conventional hemostatic tests are unsuitable for the evaluation of low-platelet samples. Here we aimed to establish suitable analytical conditions with the Total Thrombus-formation Analysis System (T-TAS) for quantitative assessment of thrombogenic potential in patients with thrombocytopenia and to investigate how T-TAS values relate to bleeding symptoms and the effects of platelet transfusion.

METHODS

Modified chips with a different chamber depth were developed for the analysis of low-platelet samples in the T-TAS. We included 10 adult patients admitted to the ICU of Kagoshima University Hospital who required platelet transfusion. Patients were divided into major and minor bleeding groups according to their bleeding scale before platelet transfusion. The thrombogenic potential of these patients before and after platelet transfusion was assessed with hemostatic function tests, including rotational thromboelastometry, multiplate aggregometry, and the T-TAS.

RESULTS

Analysis of low-platelet samples revealed that, compared with the conventional chip (80-μm-deep chamber), the modified chip (50-μm-deep chamber) achieved higher sensitivity in detecting elevation of flow pressure caused by growth of an occlusive thrombus in the T-TAS analytical chamber. All patients in the minor bleeding group retained thrombogenic potential that occluded the modified chip (occlusion time 16.3 ± 3.3 min), whereas most patients in the major bleeding group were unable to occlude the modified chip during the 30-min measurement (P <  0.01). The recovery of thrombogenic potential after platelet transfusion was confirmed with the T-TAS and correlated with the function, rather than the count, of transfused platelets. Among all evaluated parameters in hemostatic function tests, only the T-TAS showed significant differences in occlusion time and area under the curve both between the minor and major bleeding groups and between pre- and post-platelet transfusion.

CONCLUSIONS

We developed a modified microchip-based flow chamber system that reflects the hemostatic function of patients with thrombocytopenia.

Older Age and High Serum Ferritin Levels Associated With the Risk of Chronic Cytopenia in Hemodialysis Patients

Leukopenia or thrombocytopenia is sometimes observed in end-stage renal disease (ESRD) patients, but the association between chronic leukopenia or thrombocytopenia and hemodialysis (HD) is still unclear. We aimed to investigate the incidence of chronic leukopenia or thrombocytopenia in patients with ESRD who received HD and to determine the risk factors of this complication. We retrospectively analyzed ESRD patients treated with HD at Ditmanson Medical Foundation Chia-Yi Christian Hospital in 2018. The risk factors for the occurrence of chronic leukopenia and thrombocytopenia were analyzed by Cox regression models. Of the 473 patients in our study cohort, 46 (9.7%) patients had a hematologic abnormality, including 18 patients with chronic leukopenia, 18 with chronic thrombocytopenia, and 10 with pancytopenia. Multivariate analysis revealed that patient age ≥60 years at the initiation of dialysis was a significant predictor for both chronic leukopenia [adjusted hazard ratio (aHR), 2.71; 95% confidence interval (CI), 1.06-6.89] and chronic thrombocytopenia (aHR, 2.83; 95% CI, 1.08-7.35). Chronic liver disease (aHR, 3.31; 95% CI, 1.27-8.61) and serum ferritin levels >800 mg/dl (aHR, 3.29; 95% CI, 1.29-8.39) were risk factors for chronic thrombocytopenia. A trend showed that vitamin D from intravenous supplementation (aHR, 0.13; 95% CI, 0.01-1.16, P = 0.066) and serum phosphorous level (aHR, 0.73; 95% CI, 0.53-1.02, P = 0.068) may be associated with chronic thrombocytopenia. Our study demonstrated that hematological abnormality was a long-term complication of HD. These results reveal that older patients with HD and high serum ferritin levels are at an elevated risk for chronic cytopenia. Healthcare professionals should be aware of this risk when treating HD patients in order to improve their prognosis.