Choice of dialysis modality prior to kidney transplantation: Does it matter?

Anticoagulation for people receiving long-term haemodialysis

BACKGROUND

Haemodialysis (HD) requires safe and effective anticoagulation to prevent clot formation within the extracorporeal circuit during dialysis treatments to enable adequate dialysis and minimise adverse events, including major bleeding. Low molecular weight heparin (LMWH) may provide a more predictable dose, reliable anticoagulant effects and be simpler to administer than unfractionated heparin (UFH) for HD anticoagulation, but may accumulate in the kidneys and lead to bleeding.

OBJECTIVES

To assess the efficacy and safety of anticoagulation strategies (including both heparin and non-heparin drugs) for long-term HD in people with kidney failure. Any intervention preventing clotting within the extracorporeal circuit without establishing anticoagulation within the patient, such as regional citrate, citrate enriched dialysate, heparin-coated dialysers, pre-dilution haemodiafiltration (HDF), and saline flushes were also included.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to November 2023 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Registry Platform (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-randomised controlled studies (quasi-RCTs) evaluating anticoagulant agents administered during HD treatment in adults and children with kidney failure.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed the risk of bias using the Cochrane tool and extracted data. Treatment effects were estimated using random effects meta-analysis and expressed as relative risk (RR) or mean difference (MD) with 95% confidence intervals (CI). Evidence certainty was assessed using the Grading of Recommendation, Assessment, Development and Evaluation approach (GRADE).

MAIN RESULTS

We included 113 studies randomising 4535 participants. The risk of bias in each study was adjudicated as high or unclear for most risk domains. Compared to UFH, LMWH had uncertain effects on extracorporeal circuit thrombosis (3 studies, 91 participants: RR 1.58, 95% CI 0.46 to 5.42; I2 = 8%; low certainty evidence), while major bleeding and minor bleeding were not adequately reported. Regional citrate anticoagulation may lower the risk of minor bleeding compared to UFH (2 studies, 82 participants: RR 0.34, 95% CI 0.14 to 0.85; I2 = 0%; low certainty evidence). No studies reported data comparing regional citrate to UFH on risks of extracorporeal circuit thrombosis and major bleeding. The effects of very LMWH, danaparoid, prostacyclin, direct thrombin inhibitors, factor XI inhibitors or heparin-grafted membranes were uncertain due to insufficient data. The effects of different LMWH, different doses of LMWH, and the administration of LMWH anticoagulants using inlet versus outlet bloodline or bolus versus infusion were uncertain. Evidence to compare citrate to another citrate or control was scant. The effects of UFH compared to no anticoagulant therapy or different doses of UFH were uncertain. Death, dialysis vascular access outcomes, blood transfusions, measures of anticoagulation effect, and costs of interventions were rarely reported. No studies evaluated the effects of treatment on non-fatal myocardial infarction, non-fatal stroke and hospital admissions. Adverse events were inconsistently and rarely reported.

AUTHORS' CONCLUSIONS

Anticoagulant strategies, including UFH and LMWH, have uncertain comparative risks on extracorporeal circuit thrombosis, while major bleeding and minor bleeding were not adequately reported. Regional citrate may decrease minor bleeding, but the effects on major bleeding and extracorporeal circuit thrombosis were not reported. Evidence supporting clinical decision-making for different forms of anticoagulant strategies for HD is of low and very low certainty, as available studies have not been designed to measure treatment effects on important clinical outcomes.

Could thymoglobulin increase hemorrhagic risk in the perioperative transplantation period of sensitized kidney recipients?

OBJECTIVE

It has been described that thymoglobulin could increase the risk of infections and malignancies, in comparison to basiliximab. Leukopenia and thrombocytopenia are also more common within the first days after transplantation among thymoglobulin patients. Our objective was to analyze bleeding complications in this subset of patients.

MATERIAL AND METHODS

Bleeding complications were evaluated among 515 renal transplants carried out at our institution between 2012 and 2018. We compared patients treated with thymoglobulin (Group 1, N=91) with those treated with basiliximab (Group 2, N=424).

RESULTS

We found differences in platelet decrease: 95,142.2 (55,339.6) in Group 1 and 52,364.3 (69,116.6) in Group 2 (P=0.001), number of patients with severe thrombocytopenia (<75,000/mm³) (20.8% vs. 3.7%, P=0.001), number of blood units transfused (3.25 (0.572) vs. 2.2 (0.191, P=0.028) and percentage of patients that required surgery due to bleeding (18.2% vs. 7.7%, P=0.046). In a multiple lineal regression multivariable analysis (dependent variable was number of blood units transfused), only age [OR 0.037, 95% CI (0.003-0.070)] and type of immunosuppression [OR 1.592, 95% CI (1.38-2.84)] showed statistical significance.

CONCLUSIONS

The use of thymoglobulin in the perioperative transplantation period could increase bleeding complications. In our series, in the group of patients with thymoglobulin, severe thrombocytopenia was 6 times more frequent, and active bleeding that required surgery was also 2.5 times more frequent. One way to continue with the use of this immunosuppression agent, might be to adjust the dose instead of discontinuing it. The use of thymoglobulin should be a factor to consider in the postoperative period of these patients.

Recent advances of gut microbiota in chronic kidney disease patients

Chronic kidney disease (CKD) is a worldwide public health issue and has ultimately progressed to an end-stage renal disease that requires life-long dialysis or renal transplantation. However, the underlying molecular mechanism of these pathological development and progression remains to be fully understood. The human gut microbiota is made up of approximately 100 trillion microbial cells including anaerobic and aerobic species. In recent years, more and more evidence has indicated a clear association between dysbiosis of gut microbiota and CKD including immunoglobulin A (IgA) nephropathy, diabetic kidney disease, membranous nephropathy, chronic renal failure and end-stage renal disease. The current review describes gut microbial dysbiosis and metabolites in patients with CKD thus helping to understand human disease. Treatment with prebiotics, probiotics and natural products can attenuate CKD through improving dysbiosis of gut microbiota, indicating a novel intervention strategy in patients with CKD. This review also discusses therapeutic options, such as prebiotics, probiotics and natural products, for targeting dysbiosis of gut microbiota in patients to provide more specific concept-driven therapy strategy for CKD treatment.

Host/microbiota interactions-derived tryptophan metabolites modulate oxidative stress and inflammation via aryl hydrocarbon receptor signaling

Aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that induces the expression of a broad range of downstream genes such as cytochromes P450 enzymes and cyclooxygenase-2. Recent research focuses are shifting from AhR activation induced by xenobiotics to its response patterns to physiological ligands that expand our understanding of how endogenous metabolites as ligands to modulate AhR signaling pathway under homeostasis and pathological conditions. With increasing interest in AhR and its endogenous ligands, it would seem advisable to summarize a variety of endogenous ligands especially host/gut microbiota-derived tryptophan metabolites. Mounting evidence has indicated that AhR play a critical role in the regulation of redox homeostasis and immune responses. In this review, we outline the canonical and non-canonical AhR signalling pathway that is mediated by host/gut microbiota-derived tryptophan metabolites. Through several typical endogenous AhR ligands, we investigated the molecular mechanisms of AhR-induced oxidative stress and inflammation in the pathological milieu, including diabetes, diabetic kidney disease and end-stage renal disease. Finally, we summarize and emphasize the limitations and breakthrough of endogenous AhR ligands from host/microbial tryptophan catabolites. This review might provide novel diagnostic and prognostic approach for refractory human diseases and establish new therapeutic strategies for AhR activation.

The Role of Peritoneal Dialysis in Different Phases of Kidney Transplantation

The utilization of peritoneal dialysis (PD) has been increasing in the past decade owing to various government initiatives and recognition of benefits such as better preservation of residual renal function, quality of life, and lower cost. The Advancing American Kidney Health initiative aims to increase the utilization of home therapies such as PD and kidney transplantation to treat end stage kidney disease (ESKD). A natural consequence of this development is that more patients will receive PD, and many will eventually undergo kidney transplantation. Therefore, it is important to understand the effect of pretransplant PD on posttransplant outcomes such as delayed graft function (DGF), rejection, thrombosis, graft, and patient survival. Furthermore, some of these patients may develop DGF, which raises the question of the utility of PD during DGF and its risks. Although transplant is the best renal replacement therapy option, it is not everlasting, and many transplant recipients must go on dialysis after allograft failure. Can PD be a good option for these patients? This is another critical question. Furthermore, a significant proportion of nonrenal solid organ transplant recipients develop ESKD. Is PD feasible in this group? In this review, we try to address all of these questions in the light of available evidence.

Peritoneal Dialysis for Potential Kidney Transplant Recipients: Pride or Prejudice?

Kidney transplantation (KT) is recognized as the gold-standard of treatment for patients with end-stage renal disease. Additionally, it has been demonstrated that receiving a pre-emptive KT ensures the best recipient and graft survivals. However, due to an overwhelming discrepancy between the organs available and the patients on the transplant waiting list, the vast majority of transplant candidates require prolonged periods of dialysis before being transplanted. For many years, peritoneal dialysis (PD) and hemodialysis (HD) have been considered competitive renal replacement therapies (RRT). This dualistic vision has recently been questioned by evidence suggesting that an individualized and flexible approach may be more appropriate. In fact, tailored and cleverly planned changes between different RRT modalities, according to the patient's needs and characteristics, are often needed in order to achieve the best results. While home HD is still under scrutiny in this particular setting, current data seems to favor the use of PD over in-center HD in patients awaiting a KT. In this specific population, the demonstrated advantages of PD are superior quality of life, longer preservation of residual renal function, lower incidence of delayed graft function, better recipient survival, and reduced cost.

Pediatric renal transplantation; 10 years experience

Objectives

Although renal transplantation (RT) is the first treatment option for children with end-stage renal failure, the number of transplanted chil- dren remains low compared to adults. Experience of the individual pediatric transplant center is very important in the prognosis of pediatric transplant recipients. In this study, our pediatric RT experience was presented.

Material and Methods

We retrospectively analyzed the data of 27 patients who had RT in our clinic between April 2009 and April 2019.

Results

Fifteen of the patients were males, and mean age of all patients was 12.36 ± 4.18 years (range 4-17 years). The most frequent etiology for end- stage renal disease (ESRD) was vesicourethral reflux. Eighteen (66.7%) of the transplanted kidneys came from cadaveric donors and 9 (33.3%) from live donors. One patient had preemptive RT and one patient had a re-RT. Twenty-two patients were on peritoneal dialysis program and four patients were on hemodialysis program. Mean dialysis time before transplantation was 29 (3-104) months. Bleeding was the most common surgical complication. Delayed graft function developed in four patients, and all of their grafts were from cadaveric donors. Rejection developed in 12 of our patients, graft loss was observed in only four of them. Considering all patients, graft survival rates were 100% in the 1st and 3rd years, and 92% in the 5th year.

Conclusion

Pediatric RT program is difficult to establish, maintain and develop. Complications after transplantation are not uncommon; therefore, early detection and appropriate management are needed. Strategies are still needed to increase post-transplant success.

Polymorphisms in the CYP3A5 gene significantly affect the pharmacokinetics of sirolimus after kidney transplantation

Aim: Sirolimus (SIR) is an immunosuppressant with limitations, including a narrow treatment window, multiple adverse reactions and large differences within and among individuals. Objective: The correlation between numerous SNPs and SIR in terms of trough concentration in the early stage after kidney transplantation was analyzed. Materials & methods: A retrospective cohort study involving 69 kidney transplantation recipients was designed. Blood samples were collected to extract total DNAs, and trough SIR concentrations were measured. Logistic regression was used to analyze the association between SNPs and SIR trough concentrations. Results: At 7 days, 1 month and 3 months, the mean SIR trough concentration of patients in the CYP3A5 rs4646453-CC group was significantly higher than that in the CYP3A5 rs4646453-AA and CYP3A5 rs4646453-CA groups (p < 0.001) and CYP3A5 rs15524-AA group was significantly higher than that in the CYP3A5 rs15524-AG and CYP3A5 rs15524-GG groups (p < 0.001). Conclusion: Our study indicated that both CYP3A5 rs4646453 and CYP3A5 rs15524 had a certain influence on SIR trough concentration at 7 days, 1 month and 3 months.

Effects of Nutritional Knowledge of Informal Caregivers on Depression and Metabolic Outcomes of Hemodialysis Patients

Chronic renal failure (CRF) makes significant changes in the life of patients and their families. A good family support has a positive effect on successful patients' adaptation to the treatment and compliance with dietary regimen. This study aimed to examine the effects of nutritional knowledge of informal caregivers on depression and metabolic outcomes of hemodialysis patients. This was a cross-sectional study conducted at Baskent University Hemodialysis Center with 116 hemodialysis patients and their informal caregivers. Findings revealed that the caregivers who were the couple of the patients had the highest nutritional knowledge level than the other caregivers (p < .05). The postgraduate caregivers were more likely to have high nutritional knowledge level than the others (p < .05). The inflammation marker of the patients was significantly lower in the group of caregivers with higher level (T3 group) of nutritional knowledge than the others (p < .05). The mean CES-D scores were also more likely to be low in T3 group than in the others (p < .05). These findings highlight that the nutritional knowledge of caregivers of hemodialysis patients may have an additional benefit on patients' nutritional management and metabolic outcomes.

Anemia management for home dialysis including the new US public policy initiative

Patients with end-stage kidney disease (ESKD) requiring kidney replacement therapy are often treated in conventional dialysis centers at substantial cost and patient inconvenience. The recent United States Executive Order on Advancing American Kidney Health, in addition to focusing on ESKD prevention and reforming the kidney transplantation system, focuses on providing financial incentives to promote a shift toward home dialysis. In accordance with this order, a goal was set to have 80% of incident dialysis patients receiving home dialysis or a kidney transplant by 2025. Compared with conventional in-center therapy, home dialysis modalities, including both home hemodialysis and peritoneal dialysis, appear to offer equivalent or improved mortality, clinical outcomes, hospitalization rates, and quality of life in patients with ESKD in addition to greater convenience, flexibility, and cost-effectiveness. Treatment of anemia, a common complication of chronic kidney disease, may be easier to manage at home with a new class of agents, hypoxia-inducible factor-prolyl hydroxylase inhibitors, which are orally administered in contrast to the current standard of care of i.v. iron and/or erythropoiesis-stimulating agents. This review evaluates the clinical, quality-of-life, economic, and social aspects of dialysis modalities in patients with ESKD, including during the coronavirus disease 2019 pandemic; explores new therapeutics for the management of anemia in chronic kidney disease; and highlights how the proposed changes in Advancing American Kidney Health provide an opportunity to improve kidney health in the United States.

Case series of acute peritoneal dialysis in the prone position for acute kidney injury during the Covid-19 pandemic: Prone to complications?

Patients with kidney failure and acute respiratory distress syndrome (ARDS) requiring prone position have not been candidates for peritoneal dialysis (PD) due to concern with increased intra-abdominal pressure, reduction in respiratory system compliance and risks of peritoneal fluid leaks. We describe our experience in delivering acute PD during the surge in Covid-19 acute kidney injury (AKI) in the subset of patients requiring prone positioning. All seven patients included in this report were admitted to the intensive care unit with SARS-CoV-2 infection leading to ARDS, AKI and multisystem organ failure. All required renal replacement therapy, and prone positioning to improve ventilation/perfusion mismatch. All seven were able to continue PD despite prone positioning without any detrimental effects on respiratory mechanics or the need to switch to a different modality. Fluid leakage was noted in 71% of patients, but mild and readily resolved. We were able to successfully implement acute PD in ventilator-dependent prone patients suffering from Covid-19-related AKI. This required a team effort and some modifications in the conventional PD prescription and delivery.

The Genetic Polymorphism of CYP3A4 rs2242480 is Associated with Sirolimus Trough Concentrations Among Adult Renal Transplant Recipients

BACKGROUND

The large interindividual variability in the genetic polymorphisms of sirolimus (SIR)- metabolizing enzymes, transporters, and receptors can lead to qualitatively and quantitatively distinct therapeutic responses.

OBJECTIVE

We examined the impact of numerous candidate single-nucleotide polymorphisms (SNPs) involved in the trough concentration of SIR-based immunosuppressant regimen.

METHODS

This is a retrospective, long-term cohort study involving 69 renal allograft recipients. Total DNA was isolated from recipient blood samples and trough SIR concentrations were measured by microparticle enzyme immunoassay. Genome sequence reading was targeted based on next-generation sequencing. The association of tagger SNPs to SIR trough concentrations with non-genetic covariate adjusting was analyzed using logistic regression.

RESULTS

A total of 300 SNPs were genotyped in the recipient DNA samples using target sequencing analysis. Only the SNP of CYP3A4 (Ch7: 99361466 C>T, rs2242480) had a significantly higher association with SIR trough concentration as compared to the other 36 tagger SNPs. The mean trough SIR concentration of patients in the CYP3A4 rs2242480-CC group was more significant compared to that of the CYP3A4 rs2242480-TC and TT group, respectively 533.3; 157.4 and 142.5 (ng/ml)/mg/kg, P<0.0001. After adjusting the SNPs, there was no significant association between clinical factors such as age, follow-up period, the incidence of delayed graft function, immunosuppression protocol, and sex with SIR trough concentration.

CONCLUSION

These findings indicated a significant association of polymorphism in the CYP3A4 (Ch7: 99361466 C>T, rs2242480) with SIR trough concentration after 1-year administration in patients who have undergone kidney transplantation.

Anticoagulation in Patients with End-Stage Renal Disease and Atrial Fibrillation: Confusion, Concerns and Consequences

End-stage renal disease (ESRD) patients have a higher prevalence of diabetes mellitus, hypertension, congestive heart failure and advanced age, along with an increased incidence of non-valvular atrial fibrillation (AF), thereby increasing the risk for cerebrovascular accidents. Systemic anticoagulation is therefore recommended in patients with ESRD with AF to reduce the risk and complications from thromboembolism. Paradoxically, these patients are at an increased risk of bleeding due to great degree of platelet dysfunction and impaired interaction between platelet and endothelium. Currently, CHA2DS2-VASc and Hypertension, Abnormal liver/kidney function, Stroke, Bleeding, Labile INR, Elderly, Drugs or alcohol (HAS-BLED) are the recommended models for stroke risk stratification and bleeding risk assessment in patients with AF. There is conflicting data regarding benefits and risks of medications such as antiplatelet agents, warfarin and direct oral anticoagulants in ESRD patients with AF. Moreover, there is no randomized controlled trial data to guide the clinical decision making. Hence, a multi-disciplinary approach with annual re-evaluation of treatment goals and risk-benefit assessment has been recommended. In this article, we review the current recommendations with risks and benefits of anticoagulation in patients with ESRD with AF.

Pediatric kidney transplantation in Egypt: Results of 10-year single-center experience

Pediatric kidney transplantation is a multidisciplinary therapy that needs special consideration and experience. In this study, we aimed to present CUCH experience; over a 10-year period, as a specialized center of kidney transplantation in children. We studied 148 transplantations performed at a single center from 2009 to 2018. Pretransplant and follow-up data were collected and graft/patient survival rates were evaluated. A total of 48 patients developed at least one rejection episode during 688 patient-years of follow-up. Infections, recurrence of original disease, and malignancy were the most important encountered medical complications (20%, 2%, and 1.4%, respectively). One-year patient survival was 94.1%, while graft and patient survival was 91.9%. Graft/patient survival at 5, 7, and 9 years was 90%, 77%, and 58%, respectively. Infections were the main cause (69%) of mortality. Death with a functioning graft and CR were the main causes of graft loss (48% and 33%, respectively). Pediatric kidney transplantation in Egypt is still a challenging yet successful experience. Rejections and infections are the most frequent complications. Short-term outcomes surpass long-term ones and graft survival rates are similar to the international standard.

Care Needs for Organ Transplant Recipients Scale: Development and psychometric testing

BACKGROUND

Needs assessment can determine how large the gap is between needs and available services; however, no tools are available to assess the unmet needs of renal transplant recipients.

OBJECTIVES

The aim of this study was to develop the Care Needs for Organ Transplant Recipients Scale (CNOTRS) and examine its psychometric properties.

DESIGN

A cross-sectional design for instrument development and psychometric testing.

PARTICIPANTS

In total, 217 renal transplant recipients were recruited through convenience sampling.

METHODS

An initial 36-item CNOTRS was developed after a comprehensive literature review. After the CNOTRS was tested through content validity and face validity, the factor structure was explored using exploratory factor analysis (EFA). Convergent validity was examined using Pearson's correlation between the CNOTRS and Hospital Anxiety and Depression Scale (HADS). Known-group validity was tested by comparing CNOTRS scores of patients grouped based on whether they had experienced complications or rejection.

RESULTS

Twenty-eight items with three factors (namely daily care and social interaction needs, psychological needs, and health system and service needs) were identified in EFA by parallel analysis and Velicer's MAP test. The psychological needs domain had a stronger positive correlation with the HADS than the other two domains. The known-group validity was supported as a significant association between complications or rejection occurrence and unmet needs. The Cronbach's α of the CNOTRS was 0.94.

CONCLUSIONS

The CNOTRS demonstrated satisfactory reliability and validity to assess the care needs for renal transplant recipients and can assist health care professionals to tailor more personalised care for their individual needs.

Implementation of a quality improvement strategy to increase outpatient kidney transplant referrals

BACKGROUND

Kidney transplantation remains the optimal therapy for patients with end stage kidney disease (ESKD), though a small fraction of patients on dialysis are on organ waitlists. An important barrier to both preemptive kidney transplantation and successful waitlisting is timely referral to a kidney transplant center. We implemented a quality improvement strategy to improve outpatient kidney transplant referrals in a single center academic outpatient nephrology clinic.

METHODS

Over a 3 month period (July 1-September 30, 2016), we assessed the baseline kidney transplantation referral rate at our outpatient nephrology clinic for patients 18-75 years old with an estimated glomerular filtration rate (eGFR) of less than 20 mL/min/1.73m2 (2 values over 90 days apart). Charts were manually reviewed by two reviewers to look for kidney transplant referrals and documentation of discussions about kidney transplantation. We then performed a root cause analysis to explore potential barriers to kidney transplantation. Our intervention began on July 1, 2017 and included the implementation of a column in the electronic medical record (EMR) which displayed the patient's last eGFR as part of the clinic schedule. In addition, physicians were given a document listing their patients to be seen that day with an eGFR of < 20 mL/min/1.73m2. Annual education sessions were also held to discuss the importance of timely kidney transplant referral.

RESULTS

At baseline, 54 unique patients with eGFR ≤20 ml/min/1.73 m2 were identified who were seen in the Clinic between July 1, 2016 and September 30, 2016. 29.6% (16) eligible patients were referred for kidney transplantation evaluation. 69.5% (37) of these patients were not referred for kidney transplant evaluation. 46.3% (25) did not have documentation regarding kidney transplant in the EMR. nephrologist's most recent note. Following the intervention, 66 unique patients met criteria for eligibility for kidney transplant evaluation. Kidney transplant referrals increased to 60.6% (p <  0.001).

CONCLUSIONS

Our pilot implementation study of a strategy to improve outpatient kidney transplant referrals showed that a free, simple, scalable intervention can significantly improve kidney transplant referrals in the outpatient setting. This intervention targeted the nephrologist's role in the transplant referral, and facilitated the process of patient recognition and performing the referral itself without significantly interrupting the workflow. Next steps include further investigation to study the impact of early referral to kidney transplant centers on preemptive and living donor kidney transplantation as well as successful waitlisting.

Protection of the transplant kidney during cold perfusion with doxycycline: proteomic analysis in a rat model

BACKGROUND

It has been previously shown that doxycycline (Doxy) protects the kidney from preservation injury by inhibition of matrix metalloproteinase. However, the precise molecular mechanism involved in this protection from injury is not known. We used a pharmaco-proteomics approach to identify potential molecular targets associated with kidney preservation injury.

METHODS

Rat kidneys were cold perfused with or without doxycycline (Doxy) for 22 h. Kidneys perfusates were analyzed for the presence of injury markers such as lactate dehydrogenase (LDH), and neutrophil-gelatinase associated lipocalin (NGAL). Proteins extracted from kidney tissue were analyzed by 2-dimensional gel electrophoresis. Proteins of interest were identified by mass spectrometry.

RESULTS

Triosephosphate isomerase, PGM, dihydropteridine reductase-2, pyridine nucleotide-disulfide oxidoreductase, phosphotriesterase-related protein, and aminoacylase-1A were not affected by cold perfusion. Perfusion with Doxy increased their levels. N(G),N(G)-dimethylarginine dimethylaminohydrolase and phosphoglycerate kinase 1 were decreased after cold perfusion. Perfusion with Doxy led to an increase in their levels.

CONCLUSIONS

This study revealed specific metabolic enzymes involved in preservation injury and in the mechanism whereby Doxy protects the kidney against injury during cold perfusion.

Monitoring of the influence of long-term oxidative stress and ischemia on the condition of kidneys using solid-phase microextraction chemical biopsy coupled with liquid chromatography-high-resolution mass spectrometry

The limiting factor in conventional quality assessments of transplanted organs, namely the invasiveness of tissue sample collection, has prompted much research on the field of transplantology to focus on the development of alternative evaluation methods of organ quality. In the present project, we undertake the challenge to address the need for a new analytical solution for graft quality assessments by using a novel metabolomic diagnostic protocol based on low-invasive solid-phase microextraction. Solid-phase microextraction probes of ca. 0.2 mm coated with 4 mm long mixed-mode extraction phase were inserted into rabbit kidneys immediately following euthanasia and after 2, 4, 6, and 21 h of preservation. Liquid chromatography-mass spectrometry analysis of the extracts was performed with the use of a reversed phase column and a Q-Exactive Focus mass spectrometer operated in positive ionization mode. Statistical analysis of significantly changing compounds revealed metabolic profile changes in kidneys induced by ischemia and oxidative stress as a function of the duration of cold storage. The most pronounced alterations were reflected in levels of essential amino acids and purine nucleosides. Our findings demonstrate that the proposed approach may be successfully used to monitor changes in the metabolic profile of organs over time of preservation.

Scaffold-supported extracellular matrices preserved by magnesium hydroxide nanoparticles for renal tissue regeneration

Fibroblast-derived extracellular matrix-supported scaffolds made up of PLGA were prepared with the enhanced preservation of ECM components by composites with magnesium hydroxide nanoparticles, and were applied for renal tissue regeneration.

Risk of Complications and Survival of Patients Dialyzed with Permanent Catheters

Background and Objectives: An increase in the incidence of end-stage renal disease (ESRD) is associated with the need for a wider use of vascular access. Although arteriovenous (A-V) fistula is a preferred form of vascular access, for various reasons, permanent catheters are implanted in many patients. Materials and Methods: A retrospective analysis of clinical data was carried out in 398 patients (204 women) who in 2010-2016 were subjected to permanent dialysis catheters implantation as first vascular access or following A-V fistula dysfunction. The factors influencing the risk of complications related to vascular access and mortality were evaluated and the comparison of the group of patients with permanent catheter implantation after A-V fistula dysfunction with patients with first-time catheter implantation was carried out. Results: The population of 398 people with ESRD with mean age of 68.73 ± 13.26 years had a total of 495 permanent catheters implanted. In 129 (32.6%) patients, catheters were implanted after dysfunction of a previously formed dialysis fistula. An upward trend was recorded in the number of permanent catheters implanted in relation to A-V fistulas. Ninety-two infectious complications (23.1%) occurred in the study population in 65 patients (16.3%). Multivariate analysis showed that permanent catheters were more often used as the first vascular access option in elderly patients and cancer patients. Mortality in the mean 1.38 ± 1.17 years (min 0.0, max 6.70 years) follow-up period amounted to 50%. Older age and atherosclerosis were the main risk factors for mortality. Patients with dialysis fistula formed before the catheter implantation had a longer lifetime compared to the group in which the catheter was the first access. Conclusion: The use of permanent catheters for dialysis therapy is associated with a relatively high incidence of complications and low long-term survival. The main factors determining long-term survival were age and atherosclerosis. Better prognosis was demonstrated in patients after the use of A-V fistula as the first vascular access option.