Kidney Diseases最新文献

Background: Nephrotic syndrome is a special type of chronic kidney disease, the specific pathogenesis of which remains unclear. An increasing number of studies have suggested that B cells play an important role in the pathogenesis of nephrotic syndrome.

Summary: Idiopathic nephrotic syndrome is a common kidney disease in children. While previously believed to be primarily caused by T-cell disorders, recent research has shifted its focus to B cells. Studies have shown that B cells play a significant role in the pathogenesis of NS, potentially even more so than T cells. This article provides a comprehensive review of the involvement of B cells in the development of idiopathic nephrotic syndrome.

Key messages: B cells are involved in the pathogenesis of nephrotic syndrome by producing autoantibodies and various cytokines.

Introduction: Immunoglobulin A nephropathy (IgAN) patients with lower estimated glomerular filtration rate (eGFR) and higher proteinuria are at a higher risk for end-stage kidney disease (ESKD) and their prognosis is still unclear. We aim to develop and validate prognostic models in IgAN patients with chronic kidney disease (CKD) stage 3 or 4 and proteinuria ≥1.0 g/d.

Methods: Patients who came from Xijing Hospital, spanning December 2008 to January 2020 were divided into training and test cohorts randomly, with a ratio of 7:3, achieving ESKD and death as study endpoints. Created prediction models for IgAN patients based on 66 clinical and pathological characteristics using the random survival forests (RSF), survival support vector machine (SSVM), eXtreme Gradient Boosting (XGboost), and Cox regression models. The concordance index (C-index), integrated Brier scores (IBS), net reclassification index (NRI), and integrated discrimination improvement (IDI) were used to evaluate discrimination, calibration, and risk classification, respectively.

Results: A total of 263 patients were enrolled. The median follow-up time was 57.3 months, with 124 (47.1%) patients experiencing combined events. Age, blood urea nitrogen, serum uric acid, serum potassium, glomeruli sclerosis ratio, hemoglobin, and tubular atrophy/interstitial fibrosis were identified as risk factors. The RSF model predicted the prognosis with a C-index of 0.871 (0.842, 0.900) in training cohort and 0.810 (0.732, 0.888) in test cohort, which was higher than the models built by SSVM model (0.794 [0.753, 0.835] and 0.805 [0.731, 0.879], respectively), XGboost model (0.840 [0.797, 0.883] and 0.799 [0.723, 0.875], respectively) and Cox regression (0.776 [0.727, 0.825] and 0.793 [0.713, 0.873], respectively). NRI and IDI showed that the RSF model exhibited superior performance than the Cox model.

Conclusion: Our model introduced seven risk factors that may be useful in predicting the progression of IgAN patients with CKD stage 3 or 4 and proteinuria ≥1.0 g/d. The RSF model is applicable for identifying the progression of IgAN and has outperformed than SSVM, XGboost, and Cox models.

Introduction: Transcriptional coactivator with PDZ-binding motif (TAZ), a Hippo signaling pathway effector, maintains the balance of cell proliferation, differentiation, and death. However, the role of TAZ in tubular cell survival and acute kidney injury (AKI) remains largely unknown.

Methods: We used the RNA-seq database, Western blot, and immunohistochemistry to examine TAZ expression in kidneys from cisplatin-induced AKI. We generated tubular-specific TAZ knockout mice to assess the role of TAZ in cisplatin-induced renal toxicity. Immunoprecipitation-mass spectrometry followed standard procedures.

Results: TAZ was activated in tubular cells in kidneys injected with cisplatin. Conditional deletion of TAZ in tubular cells confers ferroptosis resistance and protects kidneys from cisplatin-induced AKI, whereas overexpression of TAZ(S89A) exacerbates cisplatin-induced ferroptosis. Inhibition of ferroptosis with ferrostatin-1 potently preserves renal function and alleviates morphological injury and tubular cell ferroptosis induced by cisplatin. Mechanistically, in a PPARδ-dependent manner, but not TEAD, TAZ reduces the expression of glutathione peroxidase 4 (GPX4), thus exacerbating cisplatin-induced ferroptosis.

Conclusions: Our findings show that cisplatin-induced AKI and tubular cell ferroptosis are mediated by TAZ-PPARδ interaction through regulation of GPX4, highlighting TAZ as a potential therapeutic candidate for AKI.

Introduction: Thromboembolism is a recognized complication of nephrotic syndrome (NS). Evidence supporting the use of rivaroxaban to prevent NS-related thrombosis is limited and controversial. This study aimed to explore the impact of NS on rivaroxaban pharmacokinetics and to collect observational data on the efficacy and safety of rivaroxaban as primary thromboprophylaxis in patients with NS.

Methods: This prospective study analyzed 141 patients with NS who received rivaroxaban (10 mg/day) for thromboprophylaxis. High-performance liquid chromatography-tandem mass spectrometry was used to measure the trough and peak plasma concentrations (C_trough and C_max) of rivaroxaban. The influence of clinical and genetic factors on these concentrations was examined using multivariate logistic regression.

Results: The median C_max and C_trough were 68.5 ng/mL (interquartile range [IQR], 31.7-105.5 ng/mL) and 4.4 ng/mL (IQR, 1.2-11.9 ng/mL), respectively. The incidence of thromboembolic events (TEs) was 12.8%, while that of bleeding events was 14.2%, although all were classified as minor. Albumin level was the most significant factor affecting C_max (ρ = 0.55; p < 0.001) and was also significantly associated with TEs (0.81; 0.71-0.91 per 1.0 g/dL increase; p = 0.001) and bleeding risks (1.11; 1.03-1.19 per 1.0 g/dL increase; p = 0.008). Single nucleotide polymorphisms in the ABCB1 gene significantly influenced C_trough but were not associated with clinical outcomes.

Conclusion: Hypoalbuminemia significantly affects the pharmacokinetics of rivaroxaban in NS patients. A dose-adjustment strategy based on rivaroxaban concentrations, accounting for variable albumin levels, may improve the safety and efficacy of thromboprophylaxis in this population.

Background: Increasing evidence indicates that clinicopathologic phenotypes and ANCA serotypes may differ ethnically and geographically. This review highlights the progress in the prevalence, pathogenesis, management, and outcomes of anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) in China.

Summary: AAV is not rare in China. Cumulative evidence has demonstrated a significant preponderance of microscopic polyangiitis (MPA) and myeloperoxidase (MPO)-ANCA AAV in China. Even in patients with granulomatosis with polyangiitis (GPA), there is a predominance of MPO-ANCA over proteinase 3 (PR3)-ANCA, presenting a unique subset. The pathogenesis of AAV is multifactorial, with the role of complement activation being highlighted during recent years. Treatment strategies for AAV in China have also been refined recently. A rapid tapering of glucocorticoids to minimize exposure has been recommended by the Chinese guidelines. Along with a better understanding of the disease, B cell-targeted therapy and complement-targeted therapy are developing. A considerable number of patients in China received rituximab treatment and achieved remission. However, infection risk and associated mortality still remain concerns. Therefore, less rituximab exposure should be considered and evaluated in Chinese AAV patients. Prognostic factors have been reviewed. Of note, along with improved outcomes, there is an increase of cardiovascular and malignant-related death, warranting specific care. Recently, a modified renal risk score model has been validated for early risk prediction in Chinese AAV patients. Moreover, emerging biomarkers for AAV, including complement components, have been identified in Chinese patients.

Key messages: There is a preponderance of MPA and MPO-ANCA in China. Treatment strategies for Chinese AAV patients generally align with those in western countries, and to some extent, less aggressive. Prognostic factors and emerging biomarkers for AAV in China have been identified. Further challenges include optimizing interventions, minimizing treatment-related comorbidities, improving disease monitoring, and enhancing life qualities of AAV patients.

Introduction: Previous studies have shown that rituximab (RTX) and cyclic oral corticosteroid-cyclophosphamide (CTX) regimens have similar effects on primary membranous nephropathy (PMN). However, no studies have compared RTX with an intravenous CTX regimen, which is more commonly used in China and requires fewer cumulative CTX doses.

Methods: We prospectively assigned 141 PMN patients with baseline proteinuria ≥4 g/24 h, serum albumin <30 g/L, and eGFR ≥30 mL/min × 1.73 m² despite at least 3 months of treatment with ACEI and/or ARB to the RTX group (375 mg/m² per injection per week × 4 injections) or to the CTX group (prednisone 0.8 mg/kg/day and intravenous CTX 500 mg/m² per month until the total dose reached 6-8 g). The primary endpoint was defined as a combination of partial remission or complete remission at 12 months.

Results: By the end of 12 months, 43 of 70 patients (61.43%) in the RTX group and 54 of 71 patients (76.06%) in the CTX group reached the primary endpoint (p = 0.06). Significantly fewer patients in the RTX group achieved complete remission than the CTX group (14.29% vs. 33.80%, p = 0.01). The adverse events rate was similar between the RTX group and the CTX group (28.57% vs. 40.85%, p = 0.13). In subgroup analysis, we found that fewer patients from the RTX group achieved the primary endpoint than the CTX group (48.65% vs. 74.29%, p = 0.03) among patients with massive proteinuria (urine protein ≥8 g/24 h). During the observational phase, 61 patients in the RTX group and 58 in the CTX group completed 24 months of follow-up, exhibiting similar remission rates (RTX vs. CTX: 75.41% vs. 68.97%, p = 0.54).

Conclusions: Our results show that the intravenous CTX regimen has similar safety and efficacy with higher rates of early complete remission than RTX in the treatment of PMN patients.

Introduction: Patients undergoing maintenance hemodialysis are vulnerable to coronavirus disease 2019 (COVID-19), exhibiting a high risk of hospitalization and mortality. Thus, early identification and intervention are important to prevent disease progression in these patients.

Methods: This was a two-center retrospective observational study of patients on hemodialysis diagnosed with COVID-19 at the Lingang and Xuhui campuses of Shanghai Sixth People's Hospital. Patients were randomized into the training (130) and validation cohorts (54), while 59 additional patients served as an independent external validation cohort. Artificial intelligence-based parameters of chest computed tomography (CT) were quantified, and a nomogram for patient outcomes at 14 and 28 days was created by screening quantitative CT measures, clinical data, and laboratory examination items, using univariate and multivariate Cox regression models.

Results: The median dialysis duration was 48 (interquartile range, 24-96) months. Age, diabetes mellitus, serum phosphorus level, lymphocyte count, and chest CT score were identified as independent prognostic indicators and included in the nomogram. The concordance index values were 0.865, 0.914, and 0.885 in the training, internal validation, and external validation cohorts, respectively. Calibration plots showed good agreement between the expected and actual outcomes.

Conclusion: This is the first study in which a reliable nomogram was developed to predict short-term outcomes and survival probabilities in patients with COVID-19 on hemodialysis. This model may be helpful to clinicians in treating COVID-19, managing serum phosphorus, and adjusting the dialysis strategies for these vulnerable patients to prevent disease progression in the context of COVID-19 and continuous emergence of novel viruses.

Background: Primary hyperoxaluria (PH) is a rare autosomal recessive disorder, mainly due to the increase in endogenous oxalate production, causing a series of clinical features such as kidney stones, nephrocalcinosis, progressive impairment of renal function, and systemic oxalosis. There are three common genetic causes of glycolate metabolism anomalies. Among them, PH type 1 is the most prevalent and severe type, and early end-stage renal failure often occurs.

Summary: This review summarizes PH through pathophysiology, genotype, clinical manifestation, diagnosis, and treatment options. And explore the characteristics of Chinese PH patients.

Key messages: Diagnosis of this rare disease is based on clinical symptoms, urinary or blood oxalate concentrations, liver biopsy, and genetic testing. Currently, the main treatment is massive hydration, citrate inhibition of crystallization, dialysis, liver and kidney transplantation, and pyridoxine. Recently, RNA interference drugs have also been used. In addition, technologies such as gene editing and autologous liver cell transplantation are also being developed. C.815_816insGA and c.33_34insC mutation in the AGXT gene could be a common variant in Chinese PH1 population. Mutations at the end of exon 6 account for approximately 50% of all Chinese HOGA1 mutations. Currently, the treatment of PH in China still relies mainly on symptomatic and high-throughput dialysis, with poor prognosis (especially for PH1 patients).

Introduction: Wet contamination was a common problem of peritoneal dialysis (PD) system. We developed a management algorithm for wet contamination of PD system (wet contamination) on the basis of the related research literature and clinical practice experience. The purpose of this study was to observe clinical effect of the management algorithm on the prevention of peritonitis.

Methods: Patients treated wet contamination in a single PD center between October 2017 and September 2022 were included. A management algorithm was established to treat wet contamination. It comprised identification of the contamination type, addressing contaminated or aging catheters, prophylactic antibiotics, and retraining. Demographic data and clinical data about wet contamination were collected and compared.

Results: One hundred and forty-one cases of wet contamination were included in this study. The mean age was 51.7 ± 14.1 years, and 49.6% were female. The proportion of diabetic nephropathy was 9.9%. The median PD duration was 27.0 (1.7-79.7) months. Eighteen episodes (12.8%) of wet contamination-associated peritonitis developed after wet contamination. The main pathogenic bacteria of peritonitis were Gram-positive bacteria (33.3%) and Gram-negative bacteria (27.8%). The incidence of wet contamination-associated peritonitis in the compliance with the management algorithm group was significantly lower than that in the non-compliance with the management algorithm group (0.9 vs. 48.6%; p < 0.001). Non-compliance with management algorithm (OR = 185.861, p < 0.001) together with advance age (OR = 1.116, p < 0.001) and longer distance from home to hospital (OR = 1.007, p < 0.001) were independent risk factors for wet contamination-associated peritonitis.

Conclusion: The management algorithm for wet contamination of PD system could reduce the risk of peritonitis.

Background: The NLRP3 inflammasome is a cytoplasmic polymeric protein complex composed of the cytoplasmic sensor NLRP3, the apoptosis-related spot-like protein ASC, and the inflammatory protease caspase-1. NLRP3 activates and releases IL-1β through classical pathways, and IL-18 mediates inflammation and activates gasdermin-D protein to induce cellular pyroptosis. Numerous studies have also emphasized the non-classical pathway activated by the NLRP3 inflammasome in chronic kidney disease (CKD) and the inflammasome-independent function of NLRP3.

Summary: The NLRP3-targeting inflammasome and its associated pathways have thus been widely studied in models of CKD treatment, but no drug that targets NLRP3 has thus far been approved for the treatment of CKD.

Key messages: We herein reviewed the current interventional methods for targeting the NLRP3 inflammasome in various CKD models, analyzed their underlying mechanisms of action, classified and compared them, and discussed the advantages and follow-up directions of various interventional methods. This review therefore provides novel ideas and a reference for the development of targeted NLRP3-inflammasome therapy in CKD.