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A novel infectious disease, coronavirus disease-2019 (COVID-19), spread globally since December 2019. Without effective treatment and vaccination, the strategies to restrain this disease are only keeping social distance, maintaining personal hygiene, quarantine, and isolation. However, thrice-a-week treatment is inevitable for all hemodialysis patients. In addition to the high risk of cluster infection and compromised immunity in patients with end-stage renal disease (ESRD), an atypical disease presentation could also make the medial system neglect these patients during CVOID-19 pandemic. To avoid COVID-19 transmission among patients on dialysis, the major societies of nephrology around the world have provided their guidelines for screening, dialysis facilities adjustment, and health education, respectively. In this review, we summarized the main contents and differences of these guidelines and addressed the prompt management for patients with ESRD to reduce the risk of infection during COVID-19 pandemic.

BACKGROUND: Cytosine methylation is an epigenetic mark that dictates cell fate and response to stimuli. The timing and establishment of methylation logic during kidney development remains unknown. DNA methyltransferase 3a and 3b are the enzymes capable of establishing de novo methylation. METHODS: We generated mice with genetic deletion of Dnmt3a and Dnmt3b in nephron progenitor cells (Six2(Cre)Dnmt3a/3b) and kidney tubule cells (Ksp(Cre)Dnmt3a/3b). We characterized Ksp(Cre)Dnmt3a/3b mice at baseline and after injury. Unbiased omics profiling, such as whole genome bisulfite sequencing, reduced representation bisulfite sequencing and RNA sequencing were performed on whole-kidney samples and isolated renal tubule cells. RESULTS: Ksp(Cre)Dnmt3a/3b mice showed no obvious morphologic and functional alterations at baseline. Knockout animals exhibited increased resistance to cisplatin-induced kidney injury, but not to folic acid–induced fibrosis. Whole-genome bisulfite sequencing indicated that Dnmt3a and Dnmt3b play an important role in methylation of gene regulatory regions that act as fetal-specific enhancers in the developing kidney but are decommissioned in the mature kidney. Loss of Dnmt3a and Dnmt3b resulted in failure to silence developmental genes. We also found that fetal-enhancer regions methylated by Dnmt3a and Dnmt3b were enriched for kidney disease genetic risk loci. Methylation patterns of kidneys from patients with CKD showed defects similar to those in mice with Dnmt3a and Dnmt3b deletion. CONCLUSIONS: Our results indicate a potential locus-specific convergence of genetic, epigenetic, and developmental elements in kidney disease development.

Kidney fibrosis is the histologic manifestation of CKD. Sustained activation of developmental pathways, such as Notch, in tubule epithelial cells has been shown to have a key role in fibrosis development. The molecular mechanism of Notch-induced fibrosis, however, remains poorly understood. Here, we show that, that expression of peroxisomal proliferation g-coactivator (PGC-1α) and fatty acid oxidation-related genes are lower in mice expressing active Notch1 in tubular epithelial cells (Pax8-rtTA/ICN1) compared to littermate controls. Chromatin immunoprecipitation assays revealed that the Notch target gene Hes1 directly binds to the regulatory region of PGC-1α. Compared with Pax8-rtTA/ICN1 transgenic animals, Pax8-rtTA/ICN1/Ppargc1a transgenic mice showed improvement of renal structural alterations (on histology) and molecular defect (expression of profibrotic genes). Overexpression of PGC-1α restored mitochondrial content and reversed the fatty acid oxidation defect induced by Notch overexpression in vitro in tubule cells. Furthermore, compared with Pax8-rtTA/ICN1 mice, Pax8-rtTA/ICN1/Ppargc1a mice exhibited improvement in renal fatty acid oxidation gene expression and apoptosis. Our results show that metabolic dysregulation has a key role in kidney fibrosis induced by sustained activation of the Notch developmental pathway and can be ameliorated by PGC-1α.

Background: The effect of warfarin on the risk of cardiovascular (CV) disease is unknown among chronic hemodialysis patients with atrial fibrillation (HD-AF). Methods: Population-based propensity score and prescription time-distribution matched cohort study including 6719 HD-AF patients with CHA2DS2-VASc score ≥ 2 were divided into warfarin users and nonusers and followed-up for CV events and death. Results: Warfarin treatment in HD-AF patients with AF preceding HD was associated with higher risks of developing congestive heart failure [hazard ratio (HR) = 1.82, 95% confidence interval (CI) = 1.29–2.58, p

To evaluate the long-term survival rate of critically ill sepsis survivors following cardiopulmonary resuscitation on a national scale.Retrospective and observational cohort study.Data were extracted from Taiwan's National Health Insurance Research Database.A total of 272,897 ICU patients with sepsis were identified during 2000-2010. Patients who survived to hospital discharge were enrolled. Post-discharge survival outcomes of ICU sepsis survivors who received cardiopulmonary resuscitation were compared with those of patients who did not experience cardiopulmonary arrest using propensity score matching with a 1:1 ratio.None.Only 7% (n = 3,207) of sepsis patients who received cardiopulmonary resuscitation survived to discharge. The overall 1-, 2-, and 5-year postdischarge survival rates following cardiopulmonary resuscitation were 28%, 23%, and 14%, respectively. Compared with sepsis survivors without cardiopulmonary arrest, sepsis survivors who received cardiopulmonary resuscitation had a greater risk of all-cause mortality after discharge (hazard ratio, 1.38; 95% CI, 1.34-1.46). This difference in mortality risk diminished after 2 years (hazard ratio, 1.11; 95% CI, 0.96-1.28). Multivariable analysis showed that independent risk factors for long-term mortality following cardiopulmonary resuscitation were male sex, older age, receipt of care in a nonmedical center, higher Charlson Comorbidity Index score, chronic kidney disease, cancer, respiratory infection, vasoactive agent use, and receipt of renal replacement therapy during ICU stay.The long-term outcome was worse in ICU survivors of sepsis who received in-hospital cardiopulmonary resuscitation than in those who did not, but this increased risk of mortality diminished at 2 years after discharge.

Renin-angiotensin-aldosterone system blockers are the preferred antihypertensive medications in patients with diabetes and prior stroke. This study aimed to compare the effects of angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin II receptor blockers (ARBs) in terms of major adverse cardiac events (MACEs) in patients with diabetes who survived ischemic stroke.We conducted an observational, nationwide, propensity score-matched cohort study using Taiwan's National Health Insurance Research Database. Patients aged at least 20 years with type 2 diabetes who initiated ACEI (n = 15,959) or ARB (n = 23,929) use within 90 days after discharge for first ischemic stroke between January 2000 and December 2011 were allocated to ACEI and ARB groups, respectively. The primary outcomes were MACEs (myocardial infarction, ischemic stroke, and cardiovascular mortality). The secondary outcomes were hospitalization for acute kidney injury and hyperkalemia. Intention-to-treat and as-treated models were used.Intention-to-treat analysis showed no significant difference between the ACEI and ARB groups in the outcomes of MACEs [hazard ratio (HR), 0.99; 95% confidence interval (CI), 0.95-1.04], including ischemic stroke (HR, 1.01; 95% CI, 0.97-1.06), myocardial infarction (HR, 1.06; 95% CI, 0.95-1.18), and cardiovascular mortality (HR, 0.98; 95% CI, 0.91-1.06). As-treated analysis produced similar results. Additionally, the groups showed no difference in the risk of hospitalization for acute kidney injury or hyperkalemia.Our study supports the hypothesis that the risks of MACEs and two additional secondary outcomes in patients with diabetes who survived ischemic stroke did not differ according to ACEI versus ARB use.

Background— Whether oral anticoagulant use should be considered in patients undergoing hemodialysis with atrial fibrillation (AF) remains controversial because of the uncertainty regarding risk-benefit assessments. The purpose of this study was to investigate the risk of ischemic stroke in patients undergoing hemodialysis with new-onset AF, in comparison with those without arrhythmia. Methods and Results— This nationwide, population-based, propensity score–matched cohort study used data from Taiwan’s National Health Insurance Research Database during 1998 to 2011 for patients on hemodialysis with new-onset nonvalvular AF and matched subjects without arrhythmia. The clinical end points were ischemic stroke (fatal or nonfatal), all-cause death, and other serious adverse cardiovascular events. In comparison with the matched cohort, patients with AF (n=6772) had higher risks of ischemic stroke (adjusted hazard ratio [aHR], 1.27; 95% confidence interval [CI], 1.13–1.43), all-cause death (aHR, 1.59; 95% CI, 1.52–1.67), in-hospital cardiovascular death (aHR, 1.83; 95% CI, 1.71–1.94), myocardial infarction (aHR, 1.33; 95% CI, 1.17–1.51), and hospitalization for heart failure (aHR, 1.90; 95% CI, 1.76–2.05). After considering in-hospital death as a competing risk, AF significantly increased the risk of heart failure (HR, 1.56; 95% CI, 1.45–1.68), but not those of ischemic stroke and myocardial infarction. Additionally, the predictive value of the CHA 2 DS 2 –VASc score for ischemic stroke was diminished in the competing-risk model. Conclusions— The risk of stroke was only modestly higher in patients undergoing hemodialysis with new-onset AF than in those without AF, and it became insignificant when accounting for the competing risk of in-hospital death.

Diabetic kidney disease (DKD) is a microvascular complication that leads to kidney dysfunction and ESRD, but the underlying mechanisms remain unclear. Podocyte Wnt-pathway activation has been demonstrated to be a trigger mechanism for various proteinuric diseases. Notably, four-and-a-half LIM domains protein 2 (FHL2) is highly expressed in urogenital systems and has been implicated in Wnt/β-catenin signaling. Here, we used in vitro podocyte culture experiments and a streptozotocin-induced DKD model in FHL2 gene-knockout mice to determine the possible role of FHL2 in DKD and to clarify its association with the Wnt pathway. In human and mouse kidney tissues, FHL2 protein was abundantly expressed in podocytes but not in renal tubular cells. Treatment with high glucose or diabetes-related cytokines, including angiotensin II and TGF-β1, activated FHL2 protein and Wnt/β-catenin signaling in cultured podocytes. This activation also upregulated FHL2 expression and promoted FHL2 translocation from cytosol to nucleus. Genetic deletion of the FHL2 gene mitigated the podocyte dedifferentiation caused by activated Wnt/β-catenin signaling under Wnt-On, but not under Wnt-Off, conditions. Diabetic FHL2(+/+) mice developed markedly increased albuminuria and thickening of the glomerular basement membrane compared with nondiabetic FHL2(+/+) mice. However, FHL2 knockout significantly attenuated these DKD-induced changes. Furthermore, kidney samples from patients with diabetes had a higher degree of FHL2 podocyte nuclear translocation, which was positively associated with albuminuria and progressive renal function deterioration. Therefore, we conclude that FHL2 has both structural and functional protein-protein interactions with β-catenin in the podocyte nucleus and that FHL2 protein inhibition can mitigate Wnt/β-catenin-induced podocytopathy.

Background— Substantial infective endocarditis (IE)–related morbidity and mortality may occur even after successful treatment. However, no previous study has explored long-term hard end points (ie, stroke, myocardial infarction, heart failure, cardiovascular death) in addition to all-cause mortality in IE survivors. Methods and Results— A nationwide population-based cohort study was conducted among IE survivors identified with the use of the Taiwan National Health Insurance Research Database during 2000 to 2009. IE survivors were defined as those who survived after discharge from first hospitalization with a diagnosis of IE. A total of 10 116 IE survivors were identified. IE survivors were matched to control subjects without IE at a 1:1 ratio through the use of propensity scores. The primary outcomes were stroke, myocardial infarction, readmission for heart failure, and sudden cardiac death or ventricular arrhythmia. The secondary outcomes were repeat IE and all-cause mortality. Compared with the matched cohort, IE survivors had higher risks of ischemic stroke (adjusted hazard ratio [aHR], 1.59; 95% confidence interval [CI], 1.40–1.80), hemorrhagic stroke (aHR, 2.37; 95% CI, 1.90–2.96), myocardial infarction (aHR, 1.44; 95% CI, 1.17–1.79), readmission for heart failure (aHR, 2.24; 95% CI, 2.05–2.43), sudden death or ventricular arrhythmia (aHR, 1.69; 95% CI, 1.44–1.98), and all-cause death (aHR, 2.27; 95% CI, 2.14–2.40). Risk factors for repeat IE were older age, male sex, drug abuse, and valvular replacement after an initial episode of IE. Conclusion— Despite treatment, the risk of long-term major adverse cardiac events was substantially increased in IE survivors.

Renin and aldosterone activity levels are low in elderly patients, raising concerns about the benefits and risks of angiotensin-converting-enzyme inhibitors (ACEIs) and angiotensin II receptor blockers (ARB) use. However, data from direct comparisons of the effects of ACEIs on ARBs in the elderly population remain inconclusive. In this nationwide study, all patients aged ≥ 70 years were retrieved from the Taiwan National Health Insurance database for the period 2000 to 2009 and were followed up until the end of 2010. The ARB cohort (12,347 patients who continuously used ARBs for ≥ 90 days) was matched to ACEI cohort using high-dimensional propensity score (hdPS). Intention-to-treat (ITT) and as-treated (AT) analyses were conducted. In the ITT analysis, after considering death as a competing risk, the ACEI cohort had similar risks of myocardial infarction (hazard ratio [HR] 0.92, 95% confidence interval [CI] 0.79–1.06), ischemic stroke (HR 0.98, 95% CI 0.90–1.07), and heart failure (HR 0.93, 95% CI 0.83–1.04) compared with the ARB cohort. No difference in adverse effects, such as acute kidney injury (HR 0.99, 95% CI 0.89–1.09) and hyperkalemia (HR 1.02, 95% CI 0.87–1.20), was observed between cohorts. AT analysis produced similar results to those of ITT analysis. We were unable to demonstrate a survival difference between cohorts (HR 1.03, 95% CI 0.88–1.21) after considering drug discontinuation as a competing risk in AT analysis. Our study supports the notion that ACEI and ARB users have similar risks of major adverse cardiovascular events (MACE), even in elderly populations.