Citations

Abstract Background and Aims Individuals who are most susceptible to developing PTLD are those who are EBV-negative and receive organs from EBV-positive donors (EBV R-/D+). The evidence regarding the connection between ATG induction therapy and PTLD is inconsistent. No studies have specifically examined the relationship between ATG use and PTLD in subgroups of EBV-negative transplant recipients (EBV R-). Using the UNOS database, we studied the association between the use of induction agents and PTLD in EBV R- patients. Method We analyzed data from 2007 to 2022 of EBV R- patients who underwent their first kidney-only transplant and excluded those who received induction agents other than ATG, basiliximab, or alemtuzumab. We used logistic regression to evaluate the association between induction agents and PTLD. Results Of 20,531 recipients, 50.7% received ATG, 19.13% received basiliximab, 13.42% received alemtuzumab, and 16.75% received no induction. The overall PTLD incidence was 2.14%. ATG recipients had higher rates of deceased donor transplants, higher degree of HLA mismatch, longer dialysis vintage, and were less likely to be white, compared to non-ATG recipients. Multivariate analysis showed ATG recipients had a higher risk of PTLD compared to non-ATG (odds ratio = 1.47, p<0.001). After excluding recipients who did not receive induction, ATG remained a significant independent risk factor for PTLD when compared to recipients who received either basiliximab or alemtuzumab (odds ratio = 1.35, p = 0.007). There was no statistically significant difference in PTLD risk among patients treated with basiliximab, alemtuzumab, or no induction (refer to Table 1). Conclusion The use of ATG induction in EBV-negative kidney transplant recipients is associated with a higher risk of PTLD compared to basiliximab, alemtuzumab, and no induction. The risk of PTLD should be considered when choosing induction therapy for this patient population.

Abstract Background and Aims The use of multiple markers may improve the accuracy in glomerular filtration rate (GFR) estimation especially when the interpretation of creatinine and cystatin C is limited. We sought to externally validate a recently developed multi-marker nuclear magnetic resonance (NMR)-based estimated GFR equation (eGFR-NMR) using the biracial Genetic Epidemiology Network of Arteriopathy cohort. Method We included 224 sex, race/ethnicity, and mGFR-category-matched participants. GFR was measured using urinary clearance of iothalamate (mGFR). We calculated eGFR-NMR using serum creatinine, valine, myo-inositol, and cystatin C, age, and sex. We compared the reliability of eGFR-NMR with current eGFR equations (2021 Chronic Kidney Disease Epidemiology Collaboration equations for creatinine [eGFR-Cr] and creatinine with cystatin C [eGFR-Cr-CysC]) using median bias, precision, and accuracy metrics. In particular, we evaluated its performance in age, sex, and race subgroups. Results In the overall cohort, mean age was 63 (±8) years, 54% were females, 49% were Black individuals, and mean mGFR was 78.7 (±24.3) ml/min/1.73 m2. eGFR-NMR overestimated mGFR by 2 mL/min/1.73 m2 (95% CI, 4 to 0.7) while eGFR-Cr-CysC underestimated mGFR by −5 mL/min/1.73 m2 (95% CI, −2 to −7). All equations had acceptable accuracy metrics. When stratified by age, sex, and race, eGFR-NMR performed the best among Black males age <65 years compared to current equations (Figure 1). In this subgroup, eGFR-NMR was unbiased (bias, 2mL/min/1.73 m2 [95% CI, -3 to 10]) compared to substantial biases of eGFR-Cr (bias, 17 mL/min/1.73 m2 [95% CI, 9 to 24]) and eGFR-Cr-CysC (bias, 15 mL/min/1.73 m2 [95% CI, 6 to 20]). In other subgroups, measures of accuracy for eGFR-NMR, eGFR-Cr, eGFR-Cr-CysC were generally similar. Conclusion eGFR-NMR can be used to estimate mGFR and was more accurate than CKD-EPI equations among Black males age <65 years.

Abstract Background and Aims Arterial hypertension (HTN) in association with chronic kidney disease (CKD) is a global healthcare burden, yet clinically proven treatments are limited. electro-Hydraulic Acoustic Therapy (eHAT), using ∼10% of the energy used in shockwave lithotripsy, is a promising technique to ameliorate ischemia and regenerate tissues. eHAT has been demonstrated to enhance healing in tissues such as bone, muscle, and myocardium, via several mechanisms, particularly by promoting neovascularization. Furthermore, previous animal studies demonstrated that eHAT reduces blood pressure (BP) and preserves renal function after ischemic kidney injury. The present pilot study explored the clinical safety and efficacy of eHAT and tested the hypothesis that eHAT would reduce BP and preserve renal function in patients with medically-treated hypertension and CKD. Method So far, a total of 15 patients with HTN and Stage III a/b CKD were enrolled in this prospective, single-arm study. The patients were treated with six sessions of eHAT during a 3-week period. At each session, 2400 shockwaves were applied to each kidney with 0.09 mJ/mm2 at 2.66Hz (NephrospecTM by Curespec LTD, Yehud, Israel). Follow-up (FU) visits were performed at 1, 3, and 6 months. Results The treatment was well tolerated with no major adverse events or need for analgesic treatment. Average Automated Office BP (AOBP) showed a strong tendency for a decrease in diastolic BP from baseline to the Primary Efficacy Objective at FU II (3 months post last treatment), which progressively decreased further at FU III (6 months) (Table 1). Similarly, average Office BP (OBP) detected a strong trend for a progressive decrease in systolic BP from baseline to the Primary Efficacy Objective (Table 1). Levels of eGFR appeared to slightly rise throughout the study, but this change has not reached statistical significance levels (Table 1). Conclusion The current study demonstrates that the eHAT procedure is tolerable and safe in this cohort. Moreover, a 3-week regimen tended to reduce BP and preserve eGFR in patients with controlled HTN and CKD. Therefore, electro-Hydraulic Acoustic Therapy may emerge as a novel, safe, and non-invasive alternative therapeutic approach in the management of HTN in the context of CKD.

Abstract Background and Aims At least 30% of acute kidney injury (AKI) survivors lack appropriate follow up after hospital discharge. AKI survivors have highly dynamic posthospital course which warrants close monitoring to prevent adverse outcomes. Digital health solutions like remote patient monitoring (RPM) could be used to improve quality and efficiency of AKI survivor care. The purpose for this study was to assess the feasibility and effectiveness of the Mayo Clinic AKI RPM program, launched in October 2021. Method The Mayo Clinic AKI RPM program enrolled individuals who experienced AKI during a hospitalization and underwent nephrology consultation (Figure 1). Feasibility was assessed as the proportion of individuals approached for AKI RPM enrollment during the first year of the program who submitted at least one set of vital signs after discharge. An effectiveness analysis compared stage 3 AKI survivors enrolled in AKI RPM with at least 30-days of follow-up to matched historical controls (3:1) sampled from before RPM was available (2018-2021). The primary endpoint was hospital readmission or emergency department (ED) visit within 30-days, assessed with the Chi-square test. Secondarily we explored time to first readmission or ED visit with a Kaplan-Meier survival curve with a non-parametric comparison between groups, as well as readmission length of stay with the Wilcoxon Rank Sum test due to right skewed data distribution. Results Of the 50 individuals approached for AKI RPM participation, 45 (90%) submitted at least one set of vitals. Among AKI RPM patients, 34 patients with stage 3 AKI were matched to 102 controls based on baseline characteristics and demographics. Dialysis during hospitalization (liberated by discharge) was used in 36 (27%) of patients. Sixty (44%) individuals required ICU level of care. Median (IQR) discharge estimated glomerular filtration rate was 15 (11, 27) mL/min/1.73m2. Through matching, groups were well balanced with respect to pertinent baseline demographics. Hospital readmission or ED visit occurred in 17 (50%) of AKI RPM patients within 30-days compared to 39 (38%) of controls within 30-days (P = .23). The endpoint appeared driven by ED visits within 30-days, not readmissions [At least one ED visit: 13 (38%) vs 21 (21%), respectively (P = .04); At least one hospital readmission: 7 (21%) vs 26 (26%), respectively (P = .56)]. Time to first readmission or ED visit within 30-days was similar between groups (P = .35; Figure 2). Among the 33 patients who were readmitted to the hospital within 30-days, readmission length of stay was similar in the AKI RPM group compared to controls [Median (IQR) 76 (10.6, 121) hours vs 108 (70, 165) hours); P = 0.33]. Conclusion In conclusion, AKI RPM was a feasible program when used to bridge the care continuum (hospital to home) in non-dialysis dependent AKI survivors. Incidence of at least one hospital readmission or ED visit within 30-days was statistically similar between AKI RPM patients and controls. More AKI RPM patients experienced ED encounters in the 30-days after discharge, but frequency of hospital readmission was similar. Digital health solutions such as RPM offer a unique opportunity to address the important gap in AKI care after discharging from the hospital. Additional research is needed to explore the impact of AKI RPM on patient outcomes.

Abstract Background and Aims Autologous mesenchymal stem/stromal cells (MSCs) have emerged as a therapeutic option for many chronic diseases. Hypertensive kidney disease (HKD) might impair MSCs’ reparative ability by altering important biomolecular properties of the cell, but the characteristics of this impairment are unclear. In our previous pre-clinical studies, hypoxic preconditioning (HPC) enhanced MSC angiogenesis and reduced senescence through global gene and protein expression. Thus, we hypothesize that HPC would improve human MSCs by enhancing their functionality and angiogenesis, creating an anti-inflammatory and anti-senescence environment in MSCs from healthy control (HC), hypertensive patients (HTN), and hypertensive kidney disease patients (HKD). Method Human MSCs were collected from abdominal subcutaneous fat tissue biopsy of HC, HTN, and HKD patients (n=12 each). Samples were collected from healthy volunteers with no history of hypertension or kidney disease (HC), patients diagnosed with hypertension controlled with antihypertensive drugs (HTN), and hypertensive patients with eGFR<60 mL/min/1.73 m2 (HKD). MSCs were harvested and cultured in Normoxic (20% O2) or Hypoxic (1% O2) conditions for 24-48 hours. MSC functionality was measured by migration and proliferation. Angiogenic and inflammatory secretome in conditioned media was assessed along with MSC senescence by senescence-associated beta-galactosidase (SA-beta-gal) activity. In addition, transcriptome analysis using RNA-sequencing (n=3/group) and quantitative PCR (qPCR) were performed to evaluate gene expression. Results At baseline, Normoxic HTN-MSCs interestingly had higher proliferation compared to HC. HC-MSC subjected to HPC showed increased proliferation (Figure 1A). SA-β-gal activity tended to decrease after HPC, particularly in the HC group (P = .06). HPC did not affect the release of the pro-angiogenic protein VEGF from MSCs, but increased EGF in HC-MSC, and decreased HGF in HC and HKD MSCs. HPC upregulated the pro-angiogenetic genes, inflammatory gene, and a few senescence genes (Figure 1F). Conclusion HPC has a more favorable functional effect on HC- than on HKD-MSC, reflected in increased proliferation and EGF release, and tends to decrease senescence, whereas it has little effect on HTN or HKD MSCs. These observations may assist in developing novel therapeutic strategies to improve the regenerative capacity of MSCs in patients with hypertensive kidney disease.

Abstract Background and Aims Acute kidney injury (AKI) is associated with an increased risk of progression to a severe form in every disease and, moreover, is associated with an increased mortality, and so it is also with coronavirus disease 2019 (COVID-19). AKI is a frequent complication in COVID-19 patients admitted to ICU for severe respiratory failure. ICU treatment itself indirectly could cause or exacerbate renal damage, through suboptimal fluid management, drug toxicity, or low human resources. The aims of this study were to assess AKI prevalence, fluid balance and glomerular filtration rate as a predictor of outcome in COVID-19 patients treated in the intensive care unit. Method We retrospectively analysed all adult patients admitted to the ICU at a regional hospital in northern Bavaria, from 1st March to 31st December 2020. Clinical data and laboratory results were retrospectively retrieved from the hospital information system and electronic case files. According to the severity of AKI based on the KDIGO criteria, and laboratory values were followed on the first 7 days on the ICU. In total 320 patients patients were included in the study. Level of significance was set to p<0.05. Results The mean age was 65 ± 19 years, 135 (42%) patients were females, 185 (58%) were males. Median length of ICU stay was 7 (2-13 days) in females, and 8 days (4- to 21 days) in males. At the ICU, 177 patients needed some form of ventilation, from which 109 (needed Invasive mechanical ventilation). During ICU stay, 81 patients have died, with fatality rate of 25%. Patients with AKI (n=48, 15%) at the admission to the ICU, had 2.1 times higher risk of death at the ICU than patients without AKI. There was a statistically significant difference in ICU survival based on a glomerular filtration rate, fluid balance, CRP and leukocyte values, F=1.957, p=0.026; Wilk's Λ=0.724, partial η2 = 0.276 Conclusion Acute kidney injury is common in coronavirus disease 2019, and it is associated with poor clinical outcomes. Even first couple of days at the ICU could point to the outcome, with markers of inflammation, glomerular filtration rate, and fluid balance being most valuable variables.

Abstract Background and Aims A significant number of patients with anti-neutrophil cytoplasmic antibodies (ANCA) associated vasculitis (AAV) with glomerulonephritis (AAV-GN) still progress to end-stage kidney disease (ESKD, eGFR<15mL/min/1.73m2) despite advances in remission-induction treatment. Method A retrospective cohort study on MPO- or PR3-ANCA positive patients with AAV (MPA or GPA) and ESKD at presentation. Renal recovery, dialysis discontinuation and maintenance in ESKD after standard remission-induction, with or without the use of PLEX were compared. Results We analyzed 166 patients with biopsy proven active kidney involvement and eGFR <15mL/min/1.73m2 at the time of AAV-GN diagnosis. Patients received glucocorticoids with CYC (n = 84) or with RTX (n = 72) for remission-induction, and 49 also received PLEX. The predictors for renal recovery were erythrocyte sedimentation rate, SCr at diagnosis and minimal or mild chronicity changes. We analyzed 71 patients who started dialysis with or without PLEX within 4 weeks from AAV-GN diagnosis. The predictors for dialysis discontinuation were minimal chronicity changes in kidney biopsy at the time of diagnosis (OR 6.138, [95%CI 1.389-27.118],p = 0.017) and focal glomerular involvement (OR 5.017,[95%CI 1.287-19.567],p = 0.020). Predictors for maintenance in ESKD at 12 months included higher serum creatinine (SCr) at the time of diagnosis (IRR 1.086, [95%CI 1.005-1.173],p = 0.037), moderate (IRR 3.797,[95%CI 1.090-13.225],p = 0.036), or severe chronicity changes in kidney biopsy (IRR 5.883,[95%CI 1.542–22.439],p = 0.009). Conclusion In our cohort, kidney recovery, dialysis discontinuation, and maintenance of ESKD in patients with AAV-GN and eGFR<15mL/min/1.73m2 depended on SCr and histologic findings on kidney biopsies at the time of diagnosis and was not affected by the addition of PLEX.

AbstractObjectiveTo examine the experience of interracial anxiety among health professionals and how it may affect the quality of their interactions with patients from racially marginalized populations. We explored the influence of prior interracial exposure—specifically through childhood neighborhoods, college student bodies, and friend groups—on interracial anxiety among medical students and residents. We also examined whether levels of interracial anxiety change from medical school through residency.Data SourceWeb‐based longitudinal survey data from the Medical Student Cognitive Habits and Growth Evaluation Study.Study DesignWe used a retrospective longitudinal design with four observations for each trainee. The study population consisted of non‐Black US medical trainees surveyed in their 1st and 4th years of medical school and 2nd and 3rd years of residency. Mixed effects longitudinal models were used to assess predictors of interracial anxiety and assess changes in interracial anxiety scores over time.Principal FindingsIn total, 3155 non‐Black medical trainees were followed for 7 years. Seventy‐eight percent grew up in predominantly White neighborhoods. Living in predominantly White neighborhoods and having less racially diverse friends were associated with higher levels of interracial anxiety among medical trainees. Trainees' interracial anxiety scores did not substantially change over time; interracial anxiety was highest in the 1st year of medical school, lowest in the 4th year, and increased slightly during residency.ConclusionsNeighborhood and friend group composition had independent effects on interracial anxiety, indicating that premedical racial socialization may affect medical trainees' preparedness to interact effectively with diverse patient populations. Additionally, the lack of substantial change in interracial anxiety throughout medical training suggests the importance of providing curricular tools and structure (e.g., instituting interracial cooperative learning activities) to foster the development of healthy interracial relationships.

Abstract Background and Aims Chronic kidney disease (CKD) is a progressive disorder that affects over 15% of adults worldwide. A major component of CKD pathophysiology is renal microvascular rarefaction and loss that pairs the progression of the disease and complications. We developed a translational swine model of CKD and showed that loss of renal function associates with a significant decrease in renal vascular endothelial growth factor (VEGF) signaling and progressive microvascular (MV) rarefaction. VEGF is a key endogenous cytokine for MV proliferation and repair, but underlying mechanisms of renal VEGF downregulation in CKD are unknown. We hypothesized that micro-RNA (miRNA)-mediated processes contribute to the downregulation of renal VEGF signaling in CKD. Method Unbiased renal micro-RNA (miRNA)-seq was performed in a swine model of CKD stage 3 (14 weeks of bilateral renal artery stenosis + atherogenic diet) and normal controls (n = 5/group). Micro-RNAs up- (>1.4 FC, p<0.05) and down-regulated (<0.7 FC, p<0.05) were identified, followed by target prediction analysis (miRwalk 3.0, Target Scan 7.2). Renal gene and protein expression of VEGF was measured by qPCR and western blot, respectively, and renal MV architecture was studied by 3D micro-CT. Results Unbiased miRNA-seq and target prediction analysis identified four miRs upregulated in the kidney of CKD pigs vs. controls, of which miR-451b (validated by qPCR), broadly conserved among species, was capable of targeting VEGFA (FC = 4.46, p = 0.04). Renal gene and protein expression of VEGF was downregulated in CKD vs. controls, associated with significant cortical and medullary microvascular rarefaction (Figure 1). Conclusion Our data suggest that post-transcriptional modulation of renal VEGF signaling may serve as a prominent mechanism of VEGF downregulation, which leads to MV rarefaction and disease progression in CKD. Furthermore, this work in progress identified a novel candidate (miR-451b) and may set the stage for its targeted modulation to preserve VEGF signaling as a potential strategy to protect the renal microvasculature in CKD.

Abstract Background and Aims Previous studies have shown that chronic changes on kidney biopsy are useful for stratifying the risk of kidney failure in patients with AAV-GN. We aimed to evaluate the impact of inflammatory activity for the prediction of renal outcomes. Method A retrospective cohort study of MPO- or PR3-ANCA positive patients with AAV and active renal disease. Inflammatory activity was assessed by the Activity Index (AI): a ratio between the number of crescents and/or necrosis and the total number of glomeruli (in percent). We calculated the AI score: 0-5 = 0; 6-10 = 1; 11-15 = 2; 16-20 = 3; 21-25 = 4; 26-37.5 = 5; 37.6-50 = 6; 51-65 = 7; 66-80 = 8; 80-90 = 9; 90-100 = 10. Chronicity was evaluated with the Mayo Clinic Chronicity Score (MCCS). For the combined score, we summed the MCCS and the AI. Results Results. We analyzed 326 patients with kidney biopsies available to score. The biopsies had in median (IQR), 13 glomeruli (9-20), 4 crescents (2-6) and an AI of 28.6% (15.3-47.6). The population was classified according with the risk of progression to kidney failure (KF) in 3 classes as (i) low (0-6) – 114 (35.0%), (ii) intermediate (7-11) – 152 (46.6%), and (iii) high (≥12) – 60 (18.4%). Median eGFR at baseline correlated with the overall risk categories: 42.2 vs. 22.1 vs. 13.4 mL/min/1.73 m2, p<0.0001. The proportion of patients with eGFR< 30 mL/min/1.73 m2 was increased in patients classified as high: 88.3% vs. 66.4% vs. 36.0%, p<0.0001. Renal recovery was more frequent in patients at low risk of progression: 87.7% vs. 64.6% vs. 36.6%, p<0.0001, whereas kidney failure at 12 months and dialysis were more frequent in patients at higher risk (36.7% vs. 12.4% vs. 3.8%, p<0.0001; 35.6% vs. 13.0% vs. 2.9%, p<0.0001, respectively). The combination of AI with MCCS independently predicted the risk of KF at 12 months (HR 1.916, 95%CI 1.210 - 3.033, p = 0.006), particularly increased in patients classified as high risk (HR 3.124, 95%CI 1.224 – 7.970, p = 0.017) and in patients with PR3-ANCA (HR 1.896, 95%CI 1.012 - 3.551, p = 0.046) independently of eGFR at AAV-GN diagnosis and adjusted for severity of renal involvement and age. Conclusion The combined assessment of acute inflammatory activity and chronic changes on kidney histology independently predicted renal outcomes in patients with AAV-GN. The impact of the inflammatory activity is cumulative to the chronic changes.