Life expectancy with chronic kidney disease: an educational review

Global disease burden attributable to kidney dysfunction, 1990-2019: A health inequality and trend analysis based on the global burden of disease study

OBJECTIVE

This study aimed to evaluate the burden of kidney dysfunction (KD), assess socioeconomic inequalities, and project trends in the future.

METHODS

Data on deaths, disability-adjusted life years (DALYs), years lived with disability (YLDs), and years of life lost (YLLs) were from Global Burden of Disease Study 2019. The Joinpoint regression model was utilized to analyze the temporal trend by the annual percentage change (APC). The slope index and concentration index were employed to evaluate cross-country disparities. The future trend was predicted using an age-period-cohort analysis.

RESULTS

In the past three decades, the death numbers of KD increased from 1,571,720 to 3,161,552, DALYs from 42,090,331 to 76,486,945, YLDs from 5,003,267 to 11,282,484, and YLLs from 37,087,065 to 65,204,461, respectively. The age-standardized rate (ASR) of deaths, DALYs, and YLLs exhibited a declining trend. The ASR of YLDs increased until 2017, then decreased. The slope index and concentration index for DALYs increased from 248.1 to 351.9 and from 40.70 to 57.8. In the future, the ASR of deaths, DALYs, YLDs, and YLLs will remain stable, while their numbers will continue to rise, except for YLLs.

CONCLUSIONS

The disease burden of KD remained serious. Tailored interventions should be developed based on national contexts.

Chronic kidney disease and transvenous cardiac implantable electronic device infection-is there an impact on healthcare utilization, costs, disease progression, and mortality?

AIMS

Cardiac implantable electronic device (CIED) infections are a burden to hospitals and costly for healthcare systems. Chronic kidney disease (CKD) increases the risk of CIED infections, but its differential impact on healthcare utilization, costs, and outcomes is not known.

METHODS AND RESULTS

This retrospective analysis used de-identified Medicare Fee-for-Service claims to identify patients implanted with a CIED from July 2016 to December 2020. Outcomes were defined as hospital days and costs within 12 months post-implant, post-infection CKD progression, and mortality. Generalized linear models were used to calculate results by CKD and infection status while controlling for other comorbidities, with differences between cohorts representing the incremental effect associated with CKD. A total of 584 543 patients had a CIED implant, of which 26% had CKD and 1.4% had a device infection. The average total days in hospital for infected patients was 23.5 days with CKD vs. 14.5 days (P < 0.001) without. The average cost of infection was $121 756 with CKD vs. $55 366 without (P < 0.001), leading to an incremental cost associated with CKD of $66 390. Infected patients with CKD were more likely to have septicaemia or severe sepsis than those without CKD (11.0 vs. 4.6%, P < 0.001). After infection, CKD patients were more likely to experience CKD progression (hazard ratio 1.26, P < 0.001) and mortality (hazard ratio 1.89, P < 0.001).

CONCLUSION

Cardiac implantable electronic device infection in patients with CKD was associated with more healthcare utilization, higher cost, greater disease progression, and greater mortality compared to patients without CKD.

Association between periodontitis and its treatment on mortality rates of end-stage renal disease: A systematic review and meta-analysis

BACKGROUND

The association between periodontitis and systemic diseases is widely researched. Conflicting literature exists on the relationship between periodontitis and the outcomes of end-stage renal disease (ESRD) patients. We hereby reviewed evidence to examine if periodontitis and its management impact the mortality rates of ESRD patients.

MATERIAL AND METHODS

Literature was searched on the databases of PubMed, Embase, CENTRAL, Web of Science, and Scopus till 27th April 2023. All cohort studies reporting adjusted effect size of the relationship between periodontitis or its management and mortality rates of ESRD patients were included.

RESULTS

Eight studies were eligible of which six reported the association between periodontitis and mortality while two reported between periodontal treatment and mortality. Pooled analysis showed no association between the presence of periodontitis and all-cause mortality amongst ESRD patients (HR: 1.13 95% CI: 0.77, 1.65 I2=72%). Results were unchanged on sensitivity analysis. Pooled analysis of three studies showed no difference in the risk of cardiovascular mortality amongst ESRD patients with and without periodontitis (HR: 1.44 95% CI: 0.57, 3.60 I2=86%). A descriptive analysis of two studies showed that periodontal treatment could reduce the risk of mortality in ESRD patients with periodontitis.

CONCLUSIONS

Limited evidence indicates that periodontitis does not impact all-cause and cardiovascular mortality in ESRD patients. Data on the role of periodontal therapy in improving outcomes is scarce. Further research is needed to generate high-quality evidence on this subject.

Coronary Artery Disease Assessment and Cardiovascular Events in Middle-Aged Patients on Hemodialysis

OBJECTIVE

To explore whether, in younger patients on dialysis with longer life expectancy, assessment of coronary artery disease (CAD) could identify individuals at higher risk of events and revascularization might improve outcomes in selected patients contrary to what had been observed in elderly patients.

METHODS

From August 1997 to January 2019, 2265 patients with stage 5 chronic kidney disease were prospectively referred for cardiovascular assessment. For this study, we selected 1374 asymptomatic patients aged between 18 and 64 years. After clinical risk stratification and cardiac scintigraphy by single-photon emission computed tomography, 866 patients underwent coronary angiography. The primary end point was the composite incidence of nonfatal/fatal major adverse cardiovascular events during a follow-up period of 0.1 to 189.7 months (median, 26 months). The secondary end point was all-cause mortality.

RESULTS

The primary end point occurred in 327 (23.8%) patients. Clinically stratified high-risk patients had a 3-fold increased risk of the primary end point. The prevalence of abnormal findings on perfusion scans was 29.2% (n=375), and significant CAD was found in 449 (51.8%) of 866 patients who underwent coronary angiography. An abnormal finding on myocardial perfusion scan and the presence of CAD were significantly associated with a 74% and 22% increased risk of cardiovascular events, respectively. In patients undergoing percutaneous coronary intervention or coronary artery bypass grafting (n=99), there was an 18% reduction in the risk of all-cause death relative to patients receiving medical treatment (P=.03).

CONCLUSION

In this cohort of middle-aged, asymptomatic patients on dialysis, assessment of CAD identified individuals at higher risk of events, and coronary intervention was associated with reducing the risk of death in selected patients.

Glucose Metabolism Indices and the Development of Chronic Kidney Disease: A Cohort Study of Middle-Aged and Elderly Chinese Persons

Objective

Chronic kidney disease (CKD) has become a major global health issue, and abnormalities of glucose metabolism are a risk factor responsible for development of CKD. We aimed to investigate associations between glucose metabolism indices and CKD in a Chinese population and determine which index is superior for predicting incident CKD.

Methods

We performed a community-based population on 5232 subjects aged ≥40 years without baseline CKD. CKD was defined as an estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m2 or urinary albumin-to-creatinine ratio (UACR) ≥30 mg/g. We examined the associations of glucose metabolism indices, including fasting plasma glucose (FPG), 2-hour (2 h) oral glucose tolerance test (OGTT), hemoglobin A1c (HbA1c), fasting insulin level, homeostasis model assessment of insulin resistance (HOMA-IR), and HOMA-β and the development of CKD.

Results

With an average follow-up of 3.6 years, 6.4% of the subjects developed CKD. Pearson's correlation analysis revealed that FPG, HbA1c, fasting insulin, and HOMA-IR were all significantly correlated with UACR and eGFR. The association persisted in multivariate linear regression analysis adjusted for age and sex. Compared with other glucose indices, HOMA-IR exhibited the strongest associations with CKD in COX multivariate regression analysis (HR = 1.17, 95% CI: 1.04-1.31).

Conclusion

HOMA-IR is superior to other routine indices of glucose metabolism for predicting the development of CKD in middle-aged Chinese persons. Screening with HOMA-IR may help prevent the development of CKD in the general population.

The Etiology of Kidney Failure in Indonesia: A Multicenter Study in Tertiary-Care Centers in Jakarta

BACKGROUND

Despite a large number of patients requiring dialysis, the etiology of kidney failure is poorly documented in Indonesia. With the aim to reduce the disease burden, it is essential to obtain more insight in the etiology of chronic kidney disease (CKD).

OBJECTIVES

In the present study, we attempted to investigate the primary renal disease of kidney failure patients from five tertiary-care centers in Jakarta.

METHODS

This is a multicenter, cross-sectional study of kidney failure patients receiving kidney replacement therapy (KRT), from December 2021 to July 2022. We recruited patients aged ≥18 years, had been receiving dialysis for at least three months or a kidney transplantation.

FINDINGS

This study included 1,152 patients treated with hemodialysis (68.1%), peritoneal dialysis (7.5%), and kidney transplantation (24.4%). At the start of KRT, the median (interquartile-range [IQR]) age was 48 [37-58] years with low eGFR (median [IQR]: 5.9 [4.0-8.34] ml/minute/1.73 m2). Hypertension was the main comorbidity (74.2%), followed by diabetes mellitus (30.1%). The major primary kidney disease was diabetic kidney disease (27.2%), followed by glomerulonephritis (13.0%), hypertension (11.5%), and urolithiasis (10.3%). Lupus nephritis was the common underlying etiology of secondary glomerulonephritis (91%). A high rate of unknown cause (31.1%) was also observed.

CONCLUSIONS

Our results suggest that diabetic kidney disease is the leading cause of kidney failure in Jakarta, followed by glomerulonephritis. This study highlights the need for a better approach on primary prevention of diabetes mellitus as well as to better recognize glomerulonephritis at earlier stage might have a significant impact on reduction of the rate of kidney failure in Indonesia.

Renal Disturbances during and after Radioligand Therapy of Neuroendocrine Tumors-Extended Analysis of Potential Acute and Chronic Complications

Neuroendocrine tumors (NEN) are a group of neoplasms that arise from hormonal and neural cells. Despite a common origin, their clinical symptoms and outcomes are varied. They are most commonly localized in the gastrointestinal tract. Targeted radioligand therapy (RLT) is a treatment option which has proven to be successful in recent studies. However, the possible outcomes and true safety profile of the treatment need to be fully determined, especially by new, more sensitive methods. Our study aimed to present an extended analysis of acute and chronic renal complications during and after radioligand therapy using, for the first time in the literature, innovative and complex renal parameters. Forty patients with neuroendocrine tumors underwent four courses of radioligand therapy with [¹⁷⁷Lu]Lu-DOTATATE or [¹⁷⁷Lu]Lu/[⁹⁰Y]Y-DOTATATE. Radioisotopes were administrated in intervals of 8-12 weeks, with concurrent intravenous nephroprotection. New detailed and sensitive renal parameters were used to determine the renal safety profile during and after radioisotope therapy for standard treatment of NEN. During the first and fourth courses of RLT, no change in the glomerular filtration rate (GFR) was observed. However, long-term observations one year after the treatment showed a 10% reduction in the GFR. During the first course of treatment, the fractional urea and calcium excretions increased, while the fractional potassium concentration decreased. The fractional calcium excretion remained highly increased in long-term observations. Decreases in urine IL-18, KIM-1 and albumin concentrations were observed during RLT. The concentrations of IL-18 and KIM-1 remained low even a year after therapy. The ultrasound parameters of renal perfusion changed during treatment, before partially returning to the baseline one year after therapy, and were correlated with the biochemical parameters of renal function. A permanent increase in diastolic blood pressure was correlated with the decrease in the GFR observed during the study. In this innovative and complex renal assessment during and after RLT, we found a permanent 10% per year decrease in the GFR and noticeable disturbances in renal tubule function. The diastolic blood pressure also increased.

Long-Term Kidney and Cardiovascular Complications in Pediatric Cancer Survivors

OBJECTIVE

The objective of this study was to describe the burden of adverse kidney and hypertension outcomes in patients evaluated by pediatric nephrology in a multidisciplinary survivorship clinic.

STUDY DESIGN

Retrospective chart review of all patients followed up by nephrology in our multidisciplinary survivorship clinic from August 2013 to June 2021. Data included clinic blood pressure, longitudinal ambulatory blood pressure monitoring (ABPM), echocardiography, serum creatinine, and first-morning urine protein/creatinine ratios. For patients with multiple ABPMs, results of initial and most recent ABPMs were compared.

RESULTS

Of 422 patients followed in the multidisciplinary cancer survivorship clinic, 130 were seen by nephrology. The median time after therapy completion to first nephrology visit was 8 years. The most common diagnoses were leukemia/myelodysplastic syndrome (27%), neuroblastoma (24%), and Wilms tumor (15%). At the last follow-up, 68% had impaired kidney function, 38% had a clinical diagnosis of hypertension, and 12% had proteinuria. There were 91 ABPMs performed in 55 (42%) patients. Patients with multiple ABPMs (n = 21) had statistically significant reductions in overall median blood pressure loads: systolic initial load 37% vs most recent 10% (P = .005) and diastolic load 36% vs 14% (P = .017). Patients with impaired kidney function were more likely to have received ifosfamide. Patients with hypertension were more likely to have received total body irradiation or allogeneic stem cell transplant.

CONCLUSIONS

History of leukemia/myelodysplastic syndrome, neuroblastoma, and Wilms tumor was frequent among survivors seen by nephrology. There was significant improvement in cardiovascular measures with increased recognition of hypertension and subsequent treatment.

Staged autogenous to prosthetic hemodialysis access creation strategy to maximize forearm options

OBJECTIVE

When an adequate cephalic vein is not available for fistula construction, surgeons often turn to basilic vein or prosthetic constructions. Single-stage forearm prosthetic hemodialysis accesses are associated with poor durability, and upper arm non-autogenous access options are often limited by axillary outflow failure, which inevitably drives transition to the contralateral arm or lower extremity. We hypothesized that initial creation of a modest flow proximal forearm arterial-venous anastomosis to dilate ("develop") inflow and outflow vessels, followed by a planned second-stage procedure to create a cannulation zone with a prosthetic graft in the forearm, would result in reliable and durable hemodialysis access in patients with limited options.

METHODS

We performed an institutional cohort study from 2017 to 2021 using a prospectively maintained database supplemented with adjudicated chart review. Patients without traditional autogenous hemodialysis access options in the forearm underwent an initial non-wrist arterial-venous anastomosis creation in the forearm as a first stage, followed by a second-stage interposition graft sewn to the existing inflow and venous outflow segments to create a useable cannulation zone in the forearm while leveraging vascular development. Outcomes included time from second-stage access creation to loss of primary and secondary patency, frequency of subsequent interventions, and perioperative complications.

RESULTS

The cohort included 23 patients; first-stage radial artery-based (74%) configurations were more common than brachial artery-based (26%). Mean age was 63 years (standard deviation, 14 years), and 65% were female. Median follow-up was 340 days (interquartile range [IQR], 169-701 days). Median time to cannulation from second-stage procedure was 28 days (IQR, 18-53 days). Primary, primary assisted, and secondary patency at 1 year was 16.7% (95% confidence interval [CI], 5.3%-45.8%), 34.6% (95% CI, 15.2%-66.2%), and 95.7% (95% CI, 81.3%-99.7%), respectively. Subsequent interventions occurred at a rate of 3.02 (IQR, 1.0-4.97) per person-year, with endovascular thrombectomy with or without angioplasty/stenting (70.9%) being the most common. There were no cases of steal syndrome. Infection occurred in two cases and were managed with antibiotics alone.

CONCLUSIONS

For patients without adequate distal autogenous access options, staged prosthetic graft placement in the forearm offers few short-term complications and excellent durability with active surveillance while strategically preserving the upper arm for future constructions.

Deceased donor organ allocation in pediatric transplantation: A historical narrative

BACKGROUND

Since the earliest clinical successes in solid organ transplantation, the proper method of organ allocation for children has been a contentious subject. Over the past 30-35 years, the medical and social establishments of various countries have favored some degree of preference for children on the respective waiting lists. However, the specific policies to accomplish this have varied widely and changed frequently between organ type and country.

METHODS

Organ allocation policies over time were examined. This review traces the reasons behind and the measures/principles put in place to promote early deceased donor transplantation in children.

RESULTS

Preferred allocation in children has been approached in a variety of ways and with varying degrees of commitment in different solid organ transplant disciplines and national medical systems.

CONCLUSION

The success of policies to advantage children has varied significantly by both organ and medical system. Further work is needed to optimize allocation strategies for pediatric candidates.

A review of ferric citrate clinical studies, and the rationale and design of the Ferric Citrate and Chronic Kidney Disease in Children (FIT4KiD) trial

Pediatric chronic kidney disease (CKD) is characterized by many co-morbidities, including impaired growth and development, CKD-mineral and bone disorder, anemia, dysregulated iron metabolism, and cardiovascular disease. In pediatric CKD cohorts, higher circulating concentrations of fibroblast growth factor 23 (FGF23) are associated with some of these adverse clinical outcomes, including CKD progression and left ventricular hypertrophy. It is hypothesized that lowering FGF23 levels will reduce the risk of these events and improve clinical outcomes. Reducing FGF23 levels in CKD may be accomplished by targeting two key stimuli of FGF23 production-dietary phosphate absorption and iron deficiency. Ferric citrate is approved for use as an enteral phosphate binder and iron replacement product in adults with CKD. Clinical trials in adult CKD cohorts have also demonstrated that ferric citrate decreases circulating FGF23 concentrations. This review outlines the possible deleterious effects of excess FGF23 in CKD, summarizes data from the adult CKD clinical trials of ferric citrate, and presents the Ferric Citrate and Chronic Kidney Disease in Children (FIT4KiD) study, a randomized, placebo-controlled trial to evaluate the effects of ferric citrate on FGF23 in pediatric patients with CKD stages 3-4 (ClinicalTrials.gov Identifier NCT04741646).

Establishment and Evaluation of Artificial Intelligence-Based Prediction Models for Chronic Kidney Disease under the Background of Big Data

Objective

To establish a prediction model for the risk evaluation of chronic kidney disease (CKD) to guide the management and prevention of CKD.

Methods

A total of 1263 patients with CKD and 1948 patients without CKD admitted to the Tongde Hospital of the Zhejiang Province from January 1, 2008, to December 31, 2018, were retrospectively analyzed. Spearman's correlation was used to analyze the relationship between CKD and laboratory parameters. XGBoost, random forest, Naive Bayes, support vector machine, and multivariate logistic regression algorithms were employed to establish prediction models for the risk evaluation of CKD. The accuracy, precision, recall, F1 score, and area under the receiver operating curve (AUC) of each model were compared. The new bidirectional encoder representations from transformers with light gradient boosting machine (MD-BERT-LGBM) model was used to process the unstructured data and transform it into researchable unstructured vectors, and the AUC was compared before and after processing.

Results

Differences in laboratory parameters between CKD and non-CKD patients were observed. The neutrophil ratio and white blood cell count were significantly associated with the occurrence of CKD. The XGBoost model demonstrated the best prediction effect (accuracy = 0.9088, precision = 0.9175, recall = 0.8244, F1 score = 0.8868, AUC = 0.8244), followed by the random forest model (accuracy = 0.9020, precision = 0.9318, recall = 0.7905, F1 score = 0.581, AUC = 0.9519). Comparatively, the predictions of the Naive Bayes and support vector machine models were inferior to those of the logistic regression model. The AUC of all models was improved to some extent after processing using the new MD-BERT-LGBM model.

Conclusion

The new MD-BERT-LGBM model with the inclusion of unstructured data has contributed to the higher accuracy, sensitivity, and specificity of the prediction models. Clinical features such as age, gender, urinary white blood cells, urinary red blood cells, thrombin time, serum creatinine, and total cholesterol were associated with CKD incidence.

Microneedle patches integrated with lateral flow cassettes for blood-free chronic kidney disease point-of-care testing during a pandemic

Chronic kidney disease (CKD) is the most neglected chronic disease affecting over 750 million persons in the world. Currently, many patients with cancers or other chronic diseases (i.e., CKD) struggle to receive clinical treatment or examination due to hospitals cancelling or delaying in the COVID-19 pandemic, which may increase the risk of death. Cystatin C (Cys C) has been proposed as a potential glomerular filtration rate (GFR) marker for the early detection of acute kidney injury and CKD. However, most traditional methods for Cys C detection are immunoassays using serum as a sample and are tedious to perform and economically burdensome. To diagnose the disease in the early stage and carry out daily management during the current pandemic, we developed an integration of hydrogel microneedle patch (HMNP) and lateral flow cassette (LFC) to rapidly detect Cys C in skin interstitial fluid (ISF) in 25 min for blood-free CKD management anytime and anywhere by the naked eye that can reduce the impact of an individual's quality of life and life expectancy. Conceivably, this strategy presents a wide scope in the application of numerous other diseases if corresponding analytes are available in skin ISF.

Genotype-Phenotype correlations of SCARB2 associated clinical presentation: a case report and in-depth literature review

BACKGROUND

Biallelic pathogenic variants in the SCARB2 gene have been associated with action myoclonus-renal failure (AMRF) syndrome. Even though SCARB2 associated phenotype has been reported to include typical neurological characteristics, depending on the localization and the feature of the pathogenic variants, clinical course and the presentations have been shown to differ.

CASE PRESENTATION

Whole exome sequencing (WES) analysis revealed a homozygous truncating variant (p.N45MfsX88) in SCARB2 gene in the index case, and subsequent sanger sequencing analysis validated the variant in all affected family members from a Turkish family with the clinical characteristics associated with AMRF and related disorders. Intrafamilial clinical heterogeneity with common features including dysarthria, tremor and proteinuria, and distinct features such as peripheral neuropathy (PNP), myoclonus and seizures between the affected cases, was observed in the family. In-depth literature review enabled the detailed investigation of the reported variants associated with AMRF and suggested that while the type of the variant did not have a major impact on the course of the clinical characteristics, only the C terminal localization of the pathogenic variant significantly affected the clinical presentation, particularly the age at onset (AO) of the disease.

CONCLUSIONS

In this study we showed that biallelic SCARB2 pathogenic variants might cause a spectrum of common and distinct features associated with AMRF. Of those features while the common features include myoclonus (100%), ataxia (96%), tonic clonic seizures (82%), dysarthria (68%), tremor (65%), and renal impairment (62%), the uncommon features involve PNP (17%), hearing loss (6.8%), and cognitive impairment (13.7%). AO has been found to be significantly higher in the carriers of the p.G462DfsX34 pathogenic variant. SCARB2 pathogenic variants have not been only implicated in AMRF but also in the pathogenesis of Parkinson's disease (PD) and Gaucher disease (GD), suggesting the importance of genetic and functional studies in the clinical and the diagnostic settings. Given the proven role of SCARB2 gene in the pathogenesis of AMRF, PD and GD with a wide spectrum of clinical symptoms, investigation of the possible modifiers, such as progranulin and HSP7, has a great importance.

Building human renal tracts

Severe kidney failure affects several million people worldwide. Among these are children born with abnormal renal tracts, and some carry mutations of genes active in renal tract development. Kidney transplants are in short supply, and long term dialysis does not obviate uraemia and its associated harmful effects. It has been envisaged that a combination of stem cell technology, developmental biology, and genetics will revolutionise our understanding of kidney disease and provide novel therapies for kidney failure. Here, we review progress towards making functional kidney tissues from human pluripotent stem cells. Organoids rich in immature glomeruli and tubules can be created in culture from pluripotent stem cells. Moreover, differentiation can be increased by implanting these cells into immunodeficient mice. Challenges remain to be overcome, however, before these tissues can be used for regenerative medicine therapies. Current limitations include the small size of an organoid, the lack of large blood vessels feeding it, and the lack of a urinary tract to plumb the kidney organoid. Pluripotent stem cell technology is also being used to create 'diseases in a dish' to understand the pathobiology underlying human renal tract malformations.

Mid-term clinical outcomes and complications of primary total knee arthroplasty in hemodialysis patients: a retrospective comparative cohort study

Background

Numerous patients who receive hemodialysis (HD) undergo total knee arthroplasty (TKA) due to advanced knee joint arthritis. However, there are few studies that describe the clinical outcomes and complications of TKA in HD patients. This study investigated the mid-term results of TKA in patients undergoing HD.

Methods

This single-center retrospective study compared clinical and surgical outcomes following TKA in patients who were receiving HD with those who were not. We used propensity scores to match 21 knees of 18 patients who received HD to 706 knees of 569 patients who had not received HD, from a total of 727 knees (587 patients) that underwent primary unilateral TKA. The clinical outcomes were evaluated using the American Knee Society Score-knee (AKSS-knee) and AKSS-function scores. The primary surgical outcome measure was the number of knees with postoperative complications.

Results

In both the HD and non-HD groups, postoperative AKSS-knee and function scores significantly improved when compared to preoperative values. Postoperative AKSS-knee and function scores were not significantly different between the groups. The number of knees with postoperative complications was larger in the HD group than the non-HD group within the first postoperative month, 0–12 months, 12–24 months, 0–24 months, and two years after surgery. Additionally, in the HD group, more complications occurred in the first month than any subsequent month in the two years after surgery.

Conclusions

TKA improves AKSS-knee and function scores equivalently for HD patients and non-HD patients. However, HD patients develop more complications after TKA, especially within the first month. Therefore, surgeons who perform TKA for HD patients should obtain informed consent after explaining the possible complications, and HD patients should be carefully observed following TKA.

Positron emission tomography and single photon emission computed tomography imaging of tertiary lymphoid structures during the development of lupus nephritis

Lymphoid neogenesis occurs in tissues targeted by chronic inflammatory processes, such as infection and autoimmunity. In systemic lupus erythematosus (SLE), such structures develop within the kidneys of lupus-prone mice ((NZBXNZW)F1) and are observed in kidney biopsies taken from SLE patients with lupus nephritis (LN). The purpose of this prospective longitudinal animal study was to detect early kidney changes and tertiary lymphoid structures (TLS) using in vivo imaging. Positron emission tomography (PET) by tail vein injection of 18-F-fluoro-2-deoxy-D-glucose (¹⁸F-FDG)(PET/FDG) combined with computed tomography (CT) for anatomical localization and single photon emission computed tomography (SPECT) by intraperitoneal injection of ^99mTC labeled Albumin Nanocoll (^99mTC-Nanocoll) were performed on different disease stages of NZB/W mice (n = 40) and on aged matched control mice (BALB/c) (n = 20). By using one-way ANOVA analyses, we compared two different compartmental models for the quantitative measure of ¹⁸F-FDG uptake within the kidneys. Using a new five-compartment model, we observed that glomerular filtration of ^18FFDG in lupus-prone mice decreased significantly by disease progression measured by anti-dsDNA Ab production and before onset of proteinuria. We could not visualize TLS within the kidneys, but we were able to visualize pancreatic TLS using ^99mTC Nanocoll SPECT. Based on our findings, we conclude that the five-compartment model can be used to measure changes of FDG uptake within the kidney. However, new optimal PET/SPECT tracer administration sites together with more specific tracers in combination with magnetic resonance imaging (MRI) may make it possible to detect formation of TLS and LN before clinical manifestations.

A prospective randomized feasibility trial comparing angiography and angiography with intravascular ultrasound for treatment of hemodialysis access failures

OBJECTIVE

Hemodialysis accesses suffer from limited primary patency requiring frequent interventions, revisions, or even abandonment. Prolongation of access life and usability with minimization of these adverse events is paramount. Endovascular methods are established first-line interventions for failing arteriovenous access and treatment of venous outflow stenoses. The Primary goal of this feasibility study was to evaluate intravascular ultrasound (IVUS) during interventional treatments on outcomes in those undergoing angiography for failing hemodialysis access. Secondary goals were to determine differences between IVUS and angiography on vessel and lesion characteristics and impact on treatment.

METHODS

In this prospective, randomized controlled trial, patients scheduled for angiography to evaluate and treat a failing hemodialysis access were randomized to use of angiography (DSA) alone or angiography plus IVUS (DSA + IVUS). Patients were treated by a standardized protocol and seen in follow-up at 2 weeks, and every 3 months for 2 years or until a study endpoint was reached. Measurement of vessel diameters, % stenosis, lesion length, and study endpoints (AV access thrombosis, re-intervention, or surgical revision) were recorded.

RESULTS

A total of 55 subjects were enrolled, 27 in the DSA cohort and 28 in the DSA + IVUS cohort. There were 41 treated lesions in each group. Freedom from the composite endpoint of AV access thrombosis or re-intervention was 46.3% in the DSA cohort and 61.0% in the DSA + IVUS cohort (p = 0.27). Diameter measurements matched between the two imaging modalities only 9 times out of 41 total comparison measures. In pre-treatment lesions with >80% stenosis, IVUS had a greater tendency than DSA to underestimate the severity of stenosis, whereas in pre-treatment lesions with 50-80% stenosis, DSA was more likely than IVUS to underestimate the severity of stenosis. Post-treatment % stenosis had mean difference of -7.5% between DSA versus DSA + IVUS cohorts. In five lesions with <30% stenosis measured by angiogram, IVUS led to treatment escalation.

CONCLUSION

In the interventional treatment of failing angioaccess, IVUS and angiography differ in the vast majority of cases in measurement of vessel diameter. A significant number of patients were found to have suboptimal therapeutic response by IVUS only, which led to an escalation in treatment, and in over one-third of cases, the IVUS results led to a change in treatment plan. The improved patency rates in the IVUS group was not statistically significant in this small population but should be further investigated in a larger trial.

Development and Evaluation of a Quantitative Fluorescent Lateral Flow Immunoassay for Cystatin-C, a Renal Dysfunction Biomarker

The diagnosis, prognosis, and control of chronic kidney disease rely on an understanding of the glomerular filtration rate (GFR). The renal clearance of the cystatin-C is closely associated with the GFR. Cystatin-C is a more suitable GFR marker than the commonly used creatinine. General techniques for cystatin-C calculation, such as particle-enhanced turbidimetric and nephelometric assay, are time-consuming and tedious. Here, we propose a rapid, quantitative immunoassay for the detection of cystatin-C. A fluorescence-based lateral-flow kit was developed in a sandwich format by using a monoclonal antibody. A Linear calibration was obtained over the clinical diagnostic range of 0.023-32 µg/mL and the limit of detection (LOD) was 0.023 µg/mL and the limit of quantification (LOQ) was 0.029 µg/mL. Average recoveries from spiked urine samples ranged from 96-100% and the coefficient of variation was less than 4% for both intra and inter-day assays with excellent repeatability. With the comparison with an ELISA kit, the developed kit is highly sensitive, performs well over the detection range, provides repeatable results in a short time, and can easily be used at point-of-care (POC), making it an ideal candidate for rapid testing in early detection, community screening for renal function disorders.

Effectiveness and safety among direct oral anticoagulants in nonvalvular atrial fibrillation: A multi-database cohort study with meta-analysis

AIMS

There are conflicting signals in the literature about comparative safety and effectiveness of direct oral anticoagulants (DOACs) for nonvalvular atrial fibrillation (NVAF).

METHODS

We conducted multicentre matched cohort studies with secondary meta-analysis to assess safety and effectiveness of dabigatran, rivaroxaban and apixaban across 9 administrative healthcare databases. We included adults with NVAF initiating anticoagulation therapy (dabigatran, rivaroxaban or apixaban), and constructed 3 cohorts to compare DOACs pairwise. The primary outcome was pooled hazard ratio (pHR) of ischaemic stroke or systemic thromboembolism. Secondary outcomes included pHR of major bleeding, and a composite of stroke, major bleeding, or all-cause mortality. We used proportional hazard Cox regressions models, and pooled estimates were obtained with random effect meta-analyses.

RESULTS

The cohorts included 73 414 new users of dabigatran, 92 881 of rivaroxaban, and 61 284 of apixaban. After matching, the pHRs (95% confidence intervals) comparing rivaroxaban initiation to dabigatran were: 1.11 (0.93, 1.32) for ischaemic stroke or systemic thromboembolism, 1.26 (1.09, 1.46) for major bleeding, and 1.17 (1.05, 1.30) for the composite endpoint. For apixaban vs dabigatran, they were: 0.91 (0.74, 1.12) for ischaemic stroke or systemic thromboembolism, 0.89 (0.75, 1.05) for major bleeding, and 0.94 (0.78 to 1.14) for the composite endpoint. For apixaban vs rivaroxaban, they were: 0.85 (0.74, 0.99) for ischaemic stroke or systemic thromboembolism, 0.61 (0.53, 0.70) for major bleeding, and 0.82 (0.76, 0.88) for the composite endpoint.

CONCLUSION

We found that apixaban use is associated with lower risks of stroke and bleeding compared with rivaroxaban, and similar risks compared with dabigatran.

Illness perceptions predict mortality in patients with predialysis chronic kidney disease: a prospective observational study

BACKGROUND

Illness perceptions have been shown to predict a range of psychosocial and clinical outcomes in kidney disease; including quality of life, distress, treatment adherence and even survival in end-stage renal disease patients on dialysis. The aim of this study was to evaluate whether illness perceptions impact mortality in incident predialysis Chronic Kidney Disease (CKD) patients.

METHODS

Over the study period between September 2015 and June 2019, a total of 200 participants with predialysis CKD were recruited from the Nephrology Outpatient's clinics at Mater Dei Hospital, Malta. The participants were followed up until June 2019, and the mortality information was collected. Cox proportional hazards models were used to examine the association between illness perceptions, and mortality risk, after adjustment for covariates including distress, kidney function, co-morbidity and psychological distress.

RESULTS

Of the 200 cases available for analysis, there were 43 deaths. The mean survival time was 718.55 days (min. 3 days, max. 1297 days). The cumulative survival 1-year post the assessment of the Revised Illness Perceptions Questionnaire (IPQ-R) was 93%. Stronger identity beliefs (HR = 1.199, 95% CI: 1.060-1.357, p = 0.004), perceptions of a chronic timeline (HR = 1.065, 95% CI: 1.003-1.132, p = 0.041), personal control beliefs (HR = 0.845, 95% CI: 0.748-0.955, p = 0.007) and perceptions of control over the treatment (HR = 0.812, 95% CI: 0.725-0.909, p = 0.000) demonstrated a significant association with mortality after controlling covariates. In a subsequent saturated model, perceived identity, chronic timeline and treatment control perceptions remained significant predictors of mortality, together with serum albumin, comorbidities and urea.

CONCLUSIONS

CKD patients' perceptions of treatment control, perceptions of a chronic timeline and perceived illness identity predict survival independently of clinical prognostic factors, including kidney function and co-morbidity. Illness perceptions are important and potentially modifiable risk factors in CKD. Further studies are required to test whether the assessment and the implementation of psychological interventions aimed to modify maladaptive illness perceptions influence clinical outcomes in CKD.

Transcriptome analysis of primary podocytes reveals novel calcium regulated regulatory networks

Podocytes are pivotal in establishing the selective permeability of the glomerular filtration barrier. Recently, we showed that an increase of the intracellular calcium ion concentration [Ca²⁺ ] causes a rapid and transient actin reset (CaAR) measurable through live imaging microscopy using lifeact-mCherry as an actin dye in different cell types including the podocyte. This and other studies show the critical role [Ca²⁺ ] and the actin cytoskeleton play in podocyte homeostasis. To further investigate the role of [Ca²⁺ ] and the actin cytoskeleton in podocytes, we used a double fluorescent reporter mouse model to establish a primary podocyte culture system. We treated these podocytes temporarily with a Calcium Ionophore and facultatively with Latrunculin A, an inhibitor of actin polymerization. Unbiased genome wide transcriptional analysis identified a transcriptional response in podocytes to elevated [Ca²⁺ ] levels, affecting mRNA levels of PDGF-BB, RICTOR, and MIR17HG as mediators of Ca²⁺ -signaling. Comparison of the ex vivo transcriptional response from the primary podocyte culture with glomerular transcripts across a wide spectrum of CKD disease confirmed co-regulation of transcript sets, establishing the disease relevance of the model system. Our findings demonstrate novel [Ca²⁺ ] regulated gene networks in podocytes deepening our understanding of podocyte biology and disease.

Estimating the Loss in Expectation of Life and Relative Survival Rate among Hemodialysis Patients in Iran

BACKGROUND

Information regarding the prognosis and burden of diseases can be used by policymakers to determine competing health priorities. We aimed to assess the Relative Survival Rate (RSR) and loss of expectation of life (LEL) to evaluate the prognosis and burden of diseases in Hemodialysis (HD) patients.

STUDY DESIGN

A retrospective cohort study.

METHODS

We recruited 648 HD patients referred to three referral centers in Kerman City, Iran, from 2008 to 2019. RSR, was defined as the ratio of the observed and the expected survival rates of general population for persons of the same age and sex as patients in the current study. LEL was determined as the difference between corresponding life expectancies (LE). The extended Cox proportional hazard model was used to identify variables associated with the outcome.

RESULTS

Variables associated with outcome were diabetic status and age. In the 5th year of the follow-up study, the overall RSR was 0.57. In general, for HD patients, the estimation of LE and LEL was 22.6 and 12.36 year, respectively.

CONCLUSION

HD patients, especially older patients, showed a very poor prognosis, with a large amount of lost life expectancy. Therefore, they need more care and attention from health authorities. It is suggested to estimate the cost of eliminating the risk factors causing kidney diseases.

Preventing CKD in Developed Countries

Chronic kidney disease (CKD) is an important public health concern in developed countries because of both the number of people affected and the high cost of care when prevention strategies are not effectively implemented. Prevention should start at the governance level with the institution of multisectoral polices supporting sustainable development goals and ensuring safe and healthy environments. Primordial prevention of CKD can be achieved through implementation of measures to ensure healthy fetal (kidney) development. Public health strategies to prevent diabetes, hypertension, and obesity as risk factors for CKD are important. These approaches are cost-effective and reduce the overall noncommunicable disease burden. Strategies to prevent nontraditional CKD risk factors, including nephrotoxin exposure, kidney stones, infections, environmental exposures, and acute kidney injury (AKI), need to be tailored to local needs and epidemiology. Early diagnosis and treatment of CKD risk factors such as diabetes, obesity, and hypertension are key for primary prevention of CKD. CKD tends to occur more frequently and to progress more rapidly among indigenous, minority, and socioeconomically disadvantaged populations. Special attention is required to meet the CKD prevention needs of these populations. Effective secondary prevention of CKD relies on screening of individuals at risk to detect and treat CKD early, using established and emerging strategies. Within high-income countries, barriers to accessing effective CKD therapies must be recognized, and public health strategies must be developed to overcome these obstacles, including training and support at the primary care level to identify individuals at risk of CKD, and appropriately implement clinical practice guidelines.

Screening of multiple hemoprotein-specific aptamers and their applications for the binding, quantification, and extraction of hemoproteins in a microfluidic system

The blood hemoproteins, albumin, γ-globulin, and fibrinogen, serve as biomarkers for a variety of human diseases, including kidney and hepatorenal syndromes. Therefore, there is a need to quickly and accurately measure their concentrations in blood. Herein, nucleic acid aptamers demonstrating high affinity and specificity toward these hemoproteins were selected via systematic evolution of ligands by exponential enrichment, and their ability to capture their protein targets was assessed with sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by a tetramethyl benzidine assay. The limits of detection for the hemoproteins were all around 10-3 μM, and dissociation constant values of 131, 639, and 29nM were obtained; capture rates were measured to be 66%, 71%, and 61%, which is likely to be suitable for clinical diagnostics. Furthermore, a multi-layer microfluidic disk system featuring hemoprotein-specific aptamers for depleting hemoproteins was demonstrated. It could be a promising approach to use aptamers to replace conventional antibodies.

Pregnancy in Advanced Kidney Disease: Clinical Practice Considerations on a Challenging Combination

BACKGROUND

Thanks to the advances in care, pregnancy is now attainable for the majority of young female CKD patients, although it is still a high-risk endeavor. Clinical decision-making in these cases is impacted by a myriad of factors, making (pre)pregnancy counseling a complex process. The complexities, further impacted by limited data and unknown risks regarding outcome, can cause discussions when deciding on the best care for a specific patient.

OBJECTIVES

In this article, we provide an overview of the considerations and dilemmas we encounter in preconception counseling and offer our perspective on how to deal with them in daily clinical practice.

METHODS

The main topics we discuss in our counseling are (1) the high risk of pregnancy complications, (2) the risk of permanent CKD deterioration due to pregnancy and subsequent decreased life expectancy, (3) appropriate changes in renal medication, and (4) assisted reproduction, genetic testing, and prenatal or preimplantation genetic diagnostics.

RESULTS AND CONCLUSIONS

In our clinic, we openly address moral dilemmas arising in clinical practice in pregnancy and CKD, both within the physician team and with the patient. We do this by ensuring an interpretive physician-patient interaction and shared decision-making, deliberating in a multidisciplinary setting and, if needed, with input from an expert committee.

Cardiovascular risk factors in children on dialysis: an update

Cardiovascular disease (CVD) is a life-limiting comorbidity in patients with chronic kidney disease (CKD). In childhood, imaging studies have demonstrated early phenotypic characteristics including increases in left ventricular mass, carotid artery intima-media thickness, and pulse wave velocity, which occur even in young children with early stages of CKD. Vascular calcifications are the signature of an advanced phenotype and are mainly found in adolescents and young adults treated with dialysis. Association studies have provided valuable information regarding the significance of a multitude of risk factors in promoting CVD in children with CKD by using intermediate endpoints of measurements of surrogate parameters of CVD. Dialysis aggravates pre-existing risk factors and accelerates the progression of CVD with additional dialysis-related risk factors. Coronary artery calcifications in children and young adults with CKD accumulate in a time-dependent manner on dialysis. Identification of risk factors has led to improved understanding of principal mechanisms of CKD-induced damage to the cardiovascular system. Treatment strategies include assessment and monitoring of individual risk factor load, optimization of treatment of modifiable risk factors, and intensified hemodialysis if early transplantation is not possible.

Host Lymphotoxin-β Receptor Signaling Is Crucial for Angiogenesis of Metanephric Tissue Transplanted into Lymphoid Sites

The mouse lymph node (LN) can provide a niche to grow metanephric kidney to maturity. Here, we show that signaling through the lymphotoxin-β receptor (LTβR) is critical for kidney organogenesis both in the LN and the omentum. By transplanting kidney rudiments either in the LNs of mice undergoing LTβR antagonist treatment or in the omenta of Ltbr knockout (Ltbr-/-) mice, the host LTβR signals were found to be crucial for obtaining a well-vascularized kidney graft. Indeed, defective LTβR signaling correlated with decreased expression of endothelial and angiogenic markers in kidney grafts as well as structural alterations. Because the number of glomerular endothelial cells expressing the LTβR target nuclear factor κB-inducing kinase (NIK) decreased in the absence of a functional LTβR, it was speculated that an LTβR/NIK axis mediated the angiogenetic signals required for successful ectopic kidney organogenesis, given the established role of NIK in neovascularization. However, the transplantation of kidney rudiments in omenta of Nik-/- mice revealed that NIK is dispensable for ectopic kidney vascular integration and maturation. Finally, defective LTβR signaling impaired compensatory glomerular adaptation to renal mass reduction, indicating that kidney regeneration approaches, besides whole kidney reconstruction, might benefit from the presence of LTβR signals.

Effect of Kidney Disease on Hemiarthroplasty Outcomes After Femoral Neck Fractures

OBJECTIVE

To compare the outcomes of patients with predialysis chronic kidney disease (CKD) or end-stage renal disease (ESRD) with the outcomes of patients with no kidney disease after hemiarthroplasty (HA) for femoral neck fractures (FNF).

DESIGN

Retrospective review utilizing the Nationwide Readmissions Database.

SETTING

National database incorporating inpatient data from 22 states.

PATIENTS

Using the Nationwide Readmissions Database, 214,399 patients who underwent HA after FNF between 2010 and 2014 were identified and divided into 3 groups using ICD-9 diagnosis codes: no kidney disease (n = 176,300, 82%), predialysis CKD (n = 34,400, 16%), and ESRD (n = 3,698, 2%).

INTERVENTION

HA for FNF.

MAIN OUTCOME MEASUREMENT

Mortality, blood transfusion, and postoperative complications during index hospitalization. Hospital readmission, postoperative dislocation, periprosthetic fracture, and revision surgery within 90 days of surgery.

RESULTS

Compared to patients with no kidney disease, ESRD patients had an increased risk of mortality [odds ratio (OR) = 3.76, 95% confidence interval (CI), 2.95-4.78], blood transfusion (OR = 2.35, 95% CI, 2.08-2.64), and postoperative complications (OR = 1.64, 95% CI, 1.45-1.86) during the index hospitalization as well as an increased risk of 90-day hospital readmission (OR = 3.09, 95% CI, 2.72-3.50). Interestingly, even patients with predialysis CKD had an increased risk of mortality (OR = 1.80, 95% CI, 1.59-2.05), blood transfusion (OR = 1.66, 95% CI, 1.59-1.75), and postoperative complications (OR = 2.37, 95% CI, 2.25-2.50) during the index hospitalization as well as an increased risk of 90-day hospital readmission (OR = 1.43, 95% CI, 1.37-1.51).

CONCLUSIONS

This retrospective cohort study demonstrates that both ESRD and CKD patients have worse outcomes compared to patients with no kidney disease after HA for FNF.

LEVEL OF EVIDENCE

Prognostic Level III. See instructions for authors for a complete description of levels of evidence.

Proteomics study of the antifibrotic effects of α-mangostin in a rat model of renal fibrosis

Background

Renal fibrosis is a consequence of a “faulty” wound-healing mechanism that results in the accumulation of extracellular matrix, which could lead to the impairment of renal functions. α-Mangostin (AM) may prevent the formation of liver fibrosis, but there has yet to be a conclusive investigation of its effect on renal fibrosis.

Objectives

To investigate the renoprotective effect of AM against thioacetamide (TAA)-induced renal fibrosis in rats at the morphological and proteomic levels.

Methods

We divided 18 male Wistar rats into 3 groups: a control group, a TAA-treated group, and a TAA + AM group. The various agents used to treat the rats were administered intraperitoneally over 8 weeks. Subsequently, the morphology of renal tissue was analyzed by histology using Sirius Red staining and the relative amount of stained collagen fibers quantified using ImageJ analysis. One-dimensional gel liquid chromatography with tandem mass spectrometry (GeLC-MS/MS) was used to track levels of protein expression. Proteomic bioinformatics tools including STITCH were used to correlate the levels of markers known to be involved in fibrosis with Sirius Red-stained collagen scoring.

Results

Histology revealed that AM could reduce the relative amount of collagen fibers significantly compared with the TAA group. Proteomic analysis revealed the levels of 4 proteins were modulated by AM, namely CASP8 and FADD-like apoptosis regulator (Cflar), Ragulator complex protein LAMTOR3 (Lamtor3), mitogen-activated protein kinase kinase kinase 14 (Map3k14), and C-Jun-amino-terminal kinase-interacting protein 3 (Mapk8ip3).

Conclusion

AM can attenuate renal fibrosis by the suppression of pathways involving Cflar, Lamtor3, Map3k14, and Mapk8ip3.

Donepezil Treatment for Alzheimer's Disease in Chronic Dialysis Patients

Donepezil is one of the cholinesterase inhibitors that are indicated for the treatment of mild to moderate Alzheimer's disease (AD). Pharmacokinetic analysis has shown that donepezil is primarily eliminated by renal excretion rather than biliary excretion in humans. Therefore, patients with impaired renal function are at high risk of toxicity caused by accumulation of this drug. It is also well known that dialysis patients have very often cholinergic disorders. On the other hand, with the increasing number of long-term chronic dialysis patients, the prevalence of cognitive disorders is increasing in elderly dialysis patients. Because of the above-mentioned special risks of these patients, acetylcholinesterase inhibitors, such as donepezil, are avoided to be prescribed for them. We studied 5 cases of chronic hemodialysis outpatients (3 men [70, 72, and 86 years old] and 2 women [65 and 71 years old]) who were diagnosed as having moderate AD. We administered donepezil at 2.5 mg/day orally to the patients. After 1 month's treatment, their behavioral symptoms were improved, without them having any adverse events. We enhanced the dose to 5 mg/day without the patients experiencing any episodes of drug toxicity. After 3 months of treatment with the higher dose, their cognitive and executive functions were slightly improved and their behavioral disorders were remarkably milder, without them experiencing any episodes of drug toxicity. The patients' condition remained stable for 6 months after the initial administration of the drug. All of them were followed for the 10 following years, showing a mild cognitive decline per year for the first 5 years and more severe decline for the remaining years of the follow-up. Our cases indicate that donepezil treatment under prudent use may be well tolerated and have a beneficial impact on chronic hemodialysis patients with AD.

Nephrotoxin-Related Acute Kidney Injury and Predicting High-Risk Medication Combinations in the Hospitalized Child

BACKGROUND

In the hospitalized patient, nephrotoxin exposure is one potentially modifiable risk factor for acute kidney injury (AKI). Clinical decision support based on nephrotoxin ordering was developed at our hospital to assist inpatient providers with the prevention or mitigation of nephrotoxin-related AKI. The initial decision support algorithm (Algorithm 1) was modified in order to align with a national AKI collaborative (Algorithm 2).

OBJECTIVE

Our first aim was to determine the impact of this alignment on the sensitivity and specificity of our nephrotoxin-related AKI detection system. Second, if the system efficacy was found to be suboptimal, we then sought to develop an improved model.

DESIGN

A retrospective cohort study in hospitalized patients between December 1, 2013 and November 30, 2015 (N = 14,779) was conducted.

INTERVENTIONS

With the goal of increasing nephrotoxin-related AKI detection sensitivity, a novel model based on the identification of combinations of high-risk medications was developed.

RESULTS

Application of the algorithms to our nephrotoxin use and AKI data resulted in sensitivities of 46.9% (Algorithm 1) and 43.3% (Algorithm 2, P = .22) and specificities of 73.6% and 89.3%, respectively (P < .001). Our novel AKI detection model was able to deliver a sensitivity of 74% and a specificity of 70%.

CONCLUSIONS

Modifications to our AKI detection system by adopting Algorithm 2, which included an expanded list of nephrotoxins and equally weighting each medication, did not improve our nephrotoxin-related AKI detection. It did improve our system's specificity. Sensitivity increased by >50% when we applied a novel algorithm based on observed data with identification of key medication combinations.

Mechanical versus bioprosthetic valves in patients on dialysis

Background

The aim of this study is to evaluate the outcomes of bioprosthetic versus mechanical valves in patients on dialysis.

Methods

All patients who underwent aortic (AVR) or mitral valve replacement (MVR) at a single institution from 2011-2017 were reviewed. Primary stratification was bioprosthetic versus mechanical valves. The primary outcome was all-cause mortality. Secondary outcomes included hospital readmission, valve reoperation rates and bleeding events. Kaplan-Meier curves were generated and Cox proportional hazards regression models were used for risk-adjustment.

Results

During the study period, 3,969 patients underwent AVR or MVR, of which 97 (2.4%) were on dialysis. In dialysis patients, unadjusted 30-day mortality was comparable between bioprosthetic (12.7%) versus mechanical (5.9%) valves (P=0.31). However, the bioprosthetic group had higher rates of 1-year (40.3% versus 15.2%; P=0.03) and 5-year mortality (67.9% versus 60.7%; P=0.02). Most patients were readmitted within 5 years with no differences between the groups (bioprosthetic 80.3% versus mechanical 100%; P=0.57). There were no valve reoperations in either group at 5 years. The 5-year readmission rate was higher in the mechanical cohort (10.5% versus 53.8%; P=0.05). Risk-adjusted analysis confirmed these findings, where mechanical valves were independently associated with reduced mortality at 1-year and 5-years.

Conclusions

Despite the limited life expectancy of patients on dialysis, mechanical valves have an intermediate term mortality benefit compared to bioprosthetic valves. This comes at the expense of a higher rate of readmission for bleeding. Although valve choice should consider multiple factors, these data suggest that mechanical valve usage in dialysis patients is reasonable.

Toxicological evaluation of Picralima nitida in rodents

Picralima nitida (Stapf) T. Durand and H. Durand (Apocynaceae), over the years has shown wide range of usage in African folk medicine and its safety profile in instances of prolonged use and pregnancy are major concerns. The study aimed to extensively investigate the toxicological effects of Picralima nitida in albino rodents and make appropriate extrapolations to humans. In the first phase of the experiment which evaluated the genotoxicity and subchronic toxicity of P. nitida, a total of 40 albino rats (male and female) were randomized into 4 groups of 10 animals per group. Group 1 (control group) was orally administered with 10 ml/kg of distilled water. Animals in Groups 2 to 4 were administered with aqueous seed extract of the plant at 100, 200, 400 mg/kg body weight/day, respectively. Oral administration at the designated doses was continued for 90 days after which they were sacrificed by cervical dislocation for subchronic toxicological assessment. In the genotoxicity phase, 30 female mice were randomized into 5 groups, the control group was treated with 10 ml/kg of distilled water, groups 2 to 4, treated with 100 mg/kg, 200 mg/kg and 400 mg/kg doses of extract, and the 5th group had cyclophosphamide (0.1 mg/kg). The mice were sacrificed on the 28th day for bone marrow sampling for genotoxicity testing. In the second phase of the experiment which evaluated the teratogenicity of P. nitida, graded doses of the extract were administered to pregnant rats from day 1-19. Three groups of 6 female rats per group were administered 75, 150 and 300 mg/kg aqueous extract of P. nitida and a fourth group of 6 rats used as control was administered distilled water at 10 ml/kg. On day 20, 3 dams from each group were sacrificed and the foetuses were harvested through abdominal incision for physical examination. The 3 remaining dams were allowed to litter. The litters were sacrificed at 6 weeks for biochemical, haematological and histological analyses. The LD₅₀ determined was 707.107 mg/kg. The aqueous seed extract of P. nitida was found to be genotoxic at all the test doses. There were no significant alterations in haematologic and renal parameters following subchronic administration. Notable dynamics were observed in hormonal characteristics: there was a significant dose-dependent reduction in FSH while oestradiol and progesterone showed dose-dependent increase. Furthermore, P. nitida may cause hepatopathy as shown by hepatic venous and sinusoidal congestion on hepatic histology. Also, there is non-significant reduction in total cholesterol and LDL. No significant alteration in glucose level. Furthermore, the extract produced a statistically significant decrease in birth weight (p < 0.0001). The extract induced a significant (p < 0.05) increase in creatinine and transaminase levels in the first filial of group 150 mg/kg. The platelet count was increased in all treated group (p < 0.005). All the histology of kidney in 150 mg/kg group showed vascular congestion. In conclusion, the aqueous seed extract of P. nitida has teratogenic effects and should not be used in pregnant women. Also, P. nitida is highly genotoxic and may cause hepatic damage and depletion of glutathione pool on chronic use, thereby causing oxidative stress and its potential sequelae.

The effects of intradialytic resistance training on muscle strength, psychological well-being, clinical outcomes and circulatory micro-ribonucleic acid profiles in haemodialysis patients: Protocol for a quasi-experimental study

BACKGROUND

Intradialytic resistance training (IRT) protects patients' muscle mass and functions against protein-energy wasting, malnutrition and cachexia. However, the evidence of the effects of such an intervention in haemodialysis patients is limited and not conclusive. To improve the applicability of such interventions, we need a better understanding of molecular, functional and psycho-social adaptation in dialysed patients following a physical training. Therefore, the aim of this study is to investigate the effects of IRT on lower extremity muscle functions, quality of life, and anxiety and depression, clinical outcomes and circulatory micro-ribonucleic acid (miRNA) profiles in patients on chronic haemodialysis therapy.

METHODS

We will perform a quasi-experimental study in 3 dialysis centres. Patients will be recruited via their nephrologists and will be allocated to an experimental and a control group based on the location of the patients' dialysis centre. Patients allocated to the experimental group will undergo a 12-week IRT, while the control group will remain physically inactive during dialysis. The primary outcome is the change in the maximal force produced during an isometric contraction of lower extremity muscles. Secondary outcomes regard quality of life, anxiety and depression, clinical outcomes and circulatory miRNA profiles. Patients' level of health literacy defined as the ability to get and understand health information will be also measured in the study as a potential modifier of effects.

DISCUSSION

This quasi-experimental study can add in an important way to our understanding of the effects of resistance training on dialysis patients' muscle strength, quality of life and disease-specific outcomes.

Infectious Disease Risk in Dialysis Patients: A Transdisciplinary Approach

PURPOSE OF REVIEW

Infections are a major contributor to morbidity and mortality in end-stage renal disease (ESRD) patients. A better understanding of the interplay between infectious processes and ESRD may eventually lead to the development of targeted treatment strategies aimed at lowering overall disease morbidity and mortality. Monogenic causes are a major contributor to the development of adult chronic kidney disease (CKD). Recent studies identified a genetic cause in 10% to 20% of adults with CKD. With the introduction of whole-exome sequencing (WES) into clinical mainstay, this proportion is expected to increase in the future. Once patients develop CKD/ESRD due to a genetic cause, secondary changes, such as a compromised immune status, affect overall disease progression and clinical outcomes. Stratification according to genotype may enable us to study its effects on secondary disease outcomes, such as infectious risk. Moreover, this knowledge will enable us to better understand the molecular interplay between primary disease and secondary disease outcomes.

SOURCES OF INFORMATION

We conducted a literature review using search engines such as PubMed, PubMed central, and Medline, as well as cumulative knowledge from our respective areas of expertise.

METHODS

This is a transdisciplinary perspective on infectious complications in ESRD due to monogenic causes, such as autosomal dominant polycystic kidney disease (ADPKD), combining expertise in genomics and immunology.

KEY FINDINGS

In ADPKD, infection is a frequent complication manifesting primarily as lower urinary tract infection and less frequently as renal infection. Infectious episodes may be a direct consequence of a specific underlying structural abnormality, for example the characteristic cysts, among others. However, evidence suggests that infectious disease risk is also increased in ESRD due to secondary not-well-understood disease mechanisms. These disease mechanisms may vary depending on the underlying nature of the primary disease. While the infectious disease risk is well documented in ADPKD, there are currently insufficient data on the risk in other monogenic causes of ESRD. WES in combination with novel technologies, such as RNA sequencing and single-cell RNA sequencing, can provide insight into the molecular mechanisms of disease progression in different monogenic causes of CKD/ESRD and may lead to the development of novel risk-stratification profiles in the future.

LIMITATIONS

This is not a systematic review of the literature and the proposed perspective is tainted by the authors' point of view on the topic.

IMPLICATIONS

WES in combination with novel technologies such as RNA sequencing may enable us to fully unravel underlying disease mechanisms and secondary disease outcomes in monogenic causes of CKD and better characterize individual risk profiles. This understanding will hopefully facilitate the development of novel targeted therapies.

Forearm loop arteriovenous grafts preserve and may create new upper arm access sites

INTRODUCTION

This study evaluated the mid-term patency of forearm loop arteriovenous grafts and the dilation of previously inadequate upper arm basilic and cephalic veins after failed forearm loop arteriovenous graft.

METHODS

All access procedures from September 2009 to December 2015 were reviewed. Vein mapping measurements were used to determine whether there was "adequate" upper arm cephalic and/or basilic vein, defined as ⩾3 mm by duplex ultrasound, at the time of forearm loop arteriovenous graft creation. Outcomes of forearm loop arteriovenous graft were compared with upper arm arteriovenous fistula, and primary and cumulative patencies were evaluated.

RESULTS

Thirty-eight forearm loop arteriovenous grafts and 278 upper arm arteriovenous fistulas were created. In the forearm loop arteriovenous graft cohort, nine were inserted with adequate upper arm vein, group A, and 29 were inserted with inadequate upper arm vein, group B. Cumulative patency was lower for forearm loop arteriovenous graft compared with upper arm arteriovenous fistula at 6 months, 1 year, and 2 years (67% vs 91%, 61% vs 85%, and 49% vs 80%, respectively, P < .01). Comparison of group A forearm loop arteriovenous graft and upper arm arteriovenous fistula did not show a statistical difference in cumulative patency at 6 months, 1 year, and 2 years (P = .80, .62, and .70, respectively). Of group B with failed forearm loop arteriovenous graft, 36% became candidates for upper arm arteriovenous fistula with dilation of ipsilateral upper arm cephalic or basilic vein to ⩾3 mm.

CONCLUSION

In this study, forearm loop arteriovenous graft with adequate upper arm vein did not show a statistical difference in mid-term patencies compared with upper arm arteriovenous fistula. For those forearm loop arteriovenous grafts with inadequate upper arm vein, approximately one-third of patients became candidates for upper arm arteriovenous fistula demonstrating the benefits forearm loop arteriovenous graft.

Development of a risk score for earlier diagnosis of chronic kidney disease in children

Objective

To develop a clinical score for the early identification of chronic kidney disease (CKD) in children and adolescents. The early diagnosis of CKD in childhood allows the adoption of measures to slow the progression of the disease, thereby reducing morbidity and mortality. Nevertheless, the diagnosis is often made too late for proper patient management.

Study design

We preformed a case-control study of a multicenter Brazilian sample of 752 pediatric patients; the study cases (n = 376) were CKD patients with a median estimated GFR of 37 (IQR = 22 to 57) ml/min/1.73 m². The control group (n = 376) comprised age-, gender- and center-matched children who were followed for nonrenal diseases. Potential risk factors were investigated through a standard questionnaire that included symptoms, medical history, and a clinical examination. Two multivariable models (A and B) were fitted to assess predictors of the diagnosis of CKD.

Results

In model A, 9 variables were associated with CKD diagnosis: antenatal ultrasound with urinary malformation, recurrent urinary tract infection, polyuria, abnormal urine stream, nocturia, growth curve flattening, history of hypertension, foamy urine and edema (c-statistic = 0.938). Model B had the same variables as model A, except for the addition of the history of admission during the neonatal period and the exclusion of antenatal ultrasound variables (c-statistic = 0.927).

Conclusions

The present scores may serve as a warning sign for CKD diagnosis in children among professionals working in the primary care setting where the symptoms associated with a risk of CKD may be overlooked.

Dysregulated Expression of microRNA-21 and Disease-Related Genes in Human Patients and in a Mouse Model of Alport Syndrome

Alport syndrome is a genetic disease caused by mutations in type IV collagen and is characterized by progressive kidney disease. The Col4α3^-/- mouse model recapitulates the main features of human Alport syndrome. Previously, it was reported that kidney microRNA-21 (miR-21) expression is significantly increased in Col4α3^-/- mice, and administration of anti-miR-21 oligonucleotides (anti-miR-21) attenuates kidney disease progression in Col4α3^-/- mice, indicating that miR-21 is a viable therapeutic target for Alport syndrome. However, the expression pattern of miR-21 in the kidneys of patients with human Alport syndrome has not been evaluated. Paraffin-embedded kidney specimens were obtained from 27 patients with Alport syndrome and from 10 normal controls. They were evaluated for miR-21 expression and for in situ hybridization and mRNA expression by quantitative polymerase chain reaction. In addition, anti-miR-21 was administrated to Col4α3^-/- mice at different stages of disease, and changes in proteinuria, kidney function, and survival were monitored. Transcriptomic analysis of mouse kidney was conducted using RNA sequencing. miR-21 expression was significantly elevated in kidney specimens from patients with Alport syndrome compared to normal controls. Elevated renal miR-21 expression positively correlated with 24 h urine protein, serum blood urea nitrogen, serum creatinine, and severity of kidney pathology. On histological evaluation, high levels of miR-21 were localized to damaged tubular epithelial cells and glomeruli. Kidney specimens from both humans and mice with Alport syndrome exhibited abnormal expression of genes involved in kidney injury, fibrosis, inflammation, mitochondrial function, and lipid metabolism. Administration of anti-miR-21 to Alport mice resulted in slowing of kidney function decline, partial reversal of abnormal gene expression associated with disease pathology, and improved survival. Increased levels of miR-21 in human Alport kidney samples showed a correlation with kidney disease severity measured by proteinuria, biomarkers of kidney function, and kidney histopathology scores. These human data, combined with the finding that a reduction of miR-21 in Col4α3^-/- mice improves kidney phenotype and survival, support miR-21 as a viable therapeutic target for the treatment of Alport syndrome.

The creation and maintenance of vascular access for chronic hemodialysis in the Moscow region: a five-year experience of a regional center

Aim:to analyze the results of the regional center for the creation and maintenance of vascular access for hemodialysis.

Materials and methods.We performed a retrospective analysis. In five years (2012–2016) we performed 3,837 different operations on vascular access (VA) in 1,862 patients.

Results.There is a strong dependence of type VA and the cause of CKD 5D. At the time of the HD start, the proportion of arteriovenous fistula (AVF), synthetic vascular graft (SVG) and central venous catheter (CVC) was 73.7, 0.3 and 26% for glomerulonephritis; 58.4, 0.4 and 41% for pyelonephritis; 53, 1 and 26% for diabetes mellitus; 32, 8 and 60% for polycystic disease and 33, 2 and 65% for systemic processes, respectively. After one year on HD the shares of AVF, SVG and CVC were 89, 2 and 9% for glomerulonephritis; 76, 6 and 18% of pyelonephritis; 70, 5 and 25% for diabetes mellitus; 68, 10 and 22% for polycystic disease and 53, 5 and 42% for systemic processes, respectively. In a case of start of HD via AVF, five years survival was 61% [95% CI 51.8; 71.9]; in a case of start HD via CVC with followed by conversion to AVF – 53.9% [95% CI 42.5; 67]; in a case of CVC remained the only access – 31.6% [21.4; 41.4]. Non-maturation of AVF was observed in 5.9% of new AVF (the risk increased in a case of diabetes mellitus), early thrombosis (before the first use of AVF) was observed in 12.7% of new AVF (the risk increased with diabetes, polycystic and systemic diseases). Creation of AVF a week before the start of HD or 1–2 weeks later significantly increased the risk of thrombosis. Primary patency in a year, three and five years was 77.2% (95% CI 71.7; 81.7); 48% (95% CI 41.6, 54.1); 34.1% (95% CI 27.8, 40.5) respectively; secondary patency – 87% [95% CI 83.7; 89.7]; 74.4% [95% CI 70.3; 78,12]; 60.9% [95% CI 56.4; 65.1] respectively. The use of temporary CVC is associated with a three-fold increase of the risk of infection compared with permanent CVC: IRR 3,31 (2,46; 4,43), p < 0,0001.

Conclusion.A more detailed analysis is required to identify risk factors for complications of vascular access and to optimize approaches to its creation and maintenance.

Novel Extracorporeal Dialysis Circuit to Improve the Removal Efficiency of High and Middle Molecular Weight Toxins

A new extracorporeal circuit for hemodialysis was designed with the goal of improving the middle and high molecular weight toxins removal. A recirculation pathway was added to the hemodialysis circuit and relevant pressure regulation was performed along the circuit in order to keep the ultrafiltration rate as zero. The influence of increasing the recirculation to dialysate flow rate ratio on the removal of urea, vitamin B12, and hemoglobin was investigated. This removal was also modeled by an analytical method and solved by MATLAB software. A significant increase in removal of vitamin B12 (34%) and especially hemoglobin (228%) was achieved using the recirculation flow in an adjusted hemodialysis circuit. The model showed an acceptable agreement with the experimental results which shows its applicability for prediction of different toxin removal in this circuit.

The Use of Aspirin to Reduce the Risk of Thrombotic Events in Patients With End-Stage Renal Disease: Protocol for a Randomized Controlled Trial

Background

End-stage renal disease (ESRD) is the last stage of chronic kidney disease, mainly caused by type 2 diabetes mellitus and characterized by an increased mortality risk related to cardiovascular disease. Low-dose aspirin (acetylsalicylic acid or ASA) seems to effectively prevent cardiovascular events in patients with ESRD. However, the number of interventional studies in this population remains limited and the mechanisms of aspirin-related bleeding remain poorly understood. Aspirin’s efficacy and safety may be modified by the presence of type 2 diabetes mellitus or platelet hyperreactivity.

Objective

The overall objective of this protocol is to (1) evaluate aspirin’s safety and efficacy in reducing the risk of thrombotic events in patients with ESRD on hemodialysis and (2) examine whether aspirin’s efficacy is modified by the presence of type 2 diabetes mellitus or platelet hyperreactivity. Specifically, the primary objective is to compare the 12-month rate of any thrombotic event (cardiac death, nonfatal myocardial infarction, nonfatal stroke, arteriovenous fistula thrombosis) and Thrombolysis in Myocardial Infarction (TIMI) major bleeding in patients treated with aspirin compared to those on placebo. Secondary objectives are to test for effect modification of treatment by the presence of type 2 diabetes mellitus or platelet hyperreactivity and compare the rate of TIMI minor bleeding between treatment groups.

Methods

We developed a protocol for a phase 2 randomized, single-center, placebo-controlled, triple-blind, superiority clinical trial to assess the prophylactic efficacy and safety of aspirin in patients with ESRD and on hemodialysis. It follows the ethical principles of the Declaration of Helsinki of the World Medical Association. A total of 342 participants would be enrolled over 12 months at a large dialysis center. Patients will be randomized in a 1:1 ratio and stratified by presence of type 2 diabetes mellitus and platelet hyperreactivity to receive either oral aspirin (100 mg/d) or placebo for a treatment period of 12 months. An intention-to-treat statistical analysis will be performed.

Results

The randomized clinical trial will be performed after approval by the ethical committee of the participating center and registration at ClinicalTrials.gov.

Conclusions

We provide a protocol for a randomized controlled trial to evaluate the safety and efficacy of treatment with aspirin to reduce the risk of thrombotic events. In addition, such a study would further our understanding of the mechanism of aspirin-related bleeding and help identify subgroups of best-responders and patients with a higher risk of adverse events.

Registered Report Identifier

RR1-10.2196/10516

Generation of Functioning Nephrons by Implanting Human Pluripotent Stem Cell-Derived Kidney Progenitors

Human pluripotent stem cells (hPSCs) hold great promise for understanding kidney development and disease. We reproducibly differentiated three genetically distinct wild-type hPSC lines to kidney precursors that underwent rudimentary morphogenesis in vitro. They expressed nephron and collecting duct lineage marker genes, several of which are mutated in human kidney disease. Lentiviral-transduced hPSCs expressing reporter genes differentiated similarly to controls in vitro. Kidney progenitors were subcutaneously implanted into immunodeficient mice. By 12 weeks, they formed organ-like masses detectable by bioluminescence imaging. Implants included perfused glomeruli containing human capillaries, podocytes with regions of mature basement membrane, and mesangial cells. After intravenous injection of fluorescent low-molecular-weight dextran, signal was detected in tubules, demonstrating uptake from glomerular filtrate. Thus, we have developed methods to trace hPSC-derived kidney precursors that formed functioning nephrons in vivo. These advances beyond in vitro culture are critical steps toward using hPSCs to model and treat kidney diseases.

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Reproducible differentiation to kidney progenitors in 3 hESC lines

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After subcutaneous implantation, kidney-like tissues detectable by bioluminescence

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Implant nephrons contain glomeruli, proximal and distal tubules, and collecting ducts

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Vascularized glomeruli filter intravenously injected low-molecular-weight dextran