Association between serum potassium, risk and prognosis of peritonitis in peritoneal dialysis patients - results from the Peritoneal Dialysis Telemedicine-assisted Platform Cohort (PDTAP) Study.

BACKGROUND: Hypokalemia has been associated with an increased risk of peritoneal dialysis (PD)-associated peritonitis. However, hypokalemia is commonly associated with malnutrition, inflammation, and severe coexisting comorbidities, which thus are suspected of being potential confounders. This study was aimed at testing whether hypokalemia was independently associated with the occurrence and prognosis of PD-associated peritonitis. METHODS: A national-level dataset from the Peritoneal Dialysis Telemedicine-assisted Platform Cohort (PDTAP) Study was used to explore the independent association of serum potassium with PD-associated peritonitis. Unmatched and propensity score-adjusted multivariate competing risk models, as well as univariate competing risk models following 1:1 propensity score matching, were conducted to balance potential biases between patients with and without hypokalemia. The association between potassium levels prior to peritonitis and treatment failure due to peritonitis was also investigated. RESULTS: During a median follow-up of 25.7 months in 7220 PD patients, there was a higher incidence of peritonitis in patients with serum potassium below 4.0 mmol/L compared to those with higher serum levels (677 [0.114/patient-year] vs. 914 [0.096/patient-year], P = 0.001). After adjusting for demographics, laboratory tests, residual renal function, and medication use, baseline potassium levels below 4.0 mmol/L were not linked to an increased risk of peritonitis, with a hazard ratio of 0.983 (95% CI 0.855-1.130, P = 0.810). This result remained consistent in both the propensity score adjusted multivariate competing risk regression (HR = 0.974, 95% CI 0.829-1.145, P = 0.750) and the univariate competing risk regression after 1:1 propensity score matching (Fine-Gray test, P = 0.218). The results were similar when analyzing patients with serum potassium level above or below 3.5 mmol/L. Lastly, hypokalemia before the occurrence of peritonitis was not independently associated with treatment failure. CONCLUSION: Hypokalemia was not found to be an independent risk factor for PD-associated peritonitis or treatment failure of peritonitis in China.

Cut-off values of haemoglobin and clinical outcomes in incident peritoneal dialysis: the PDTAP study.

BACKGROUND: To explore the cut-off values of haemoglobin (Hb) on adverse clinical outcomes in incident peritoneal dialysis (PD) patients based on a national-level database. METHODS: The observational cohort study was from the Peritoneal Dialysis Telemedicine-assisted Platform (PDTAP) dataset. The primary outcomes were all-cause mortality, major adverse cardiovascular events (MACE) and modified MACE (MACE+). The secondary outcomes were the occurrences of hospitalization, first-episode peritonitis and permanent transfer to haemodialysis (HD). RESULTS: A total of 2591 PD patients were enrolled between June 2016 and April 2019 and followed up until December 2020. Baseline and time-averaged Hb <100 g/l were associated with all-cause mortality, MACE, MACE+ and hospitalizations. After multivariable adjustments, only time-averaged Hb <100 g/l significantly predicted a higher risk for all-cause mortality {hazard ratio [HR] 1.83 [95% confidence interval (CI) 1.19-281], P = .006}, MACE [HR 1.99 (95% CI 1.16-3.40), P = .012] and MACE+ [HR 1.77 (95% CI 1.15-2.73), P = .010] in the total cohort. No associations between Hb and hospitalizations, transfer to HD and first-episode peritonitis were observed. Among patients with Hb ≥100 g/l at baseline, younger age, female, use of iron supplementation, lower values of serum albumin and renal Kt/V independently predicted the incidence of Hb <100 g/l during the follow-up. CONCLUSION: This study provided real-world evidence on the cut-off value of Hb for predicting poorer outcomes through a nation-level prospective PD cohort.

Lower limb arterial thrombosis in an adult with membranous glomerulonephritis.

Massive proteinuria and hypoalbuminemia are potential risk factors in thromboembolic complications. Venous thrombosis is a frequent complication of thromboembolism in patients with membranous glomerulonephritis, while arterial thrombosis is much less reported. A 35-year-old man presented with nephrotic syndrome and osteofascial compartment syndrome in the right lower limb due to arterial thrombosis. The biopsy findings were consistent with those of stage 2 membranous nephropathy. After immunotherapy (steroids and cyclosporine), the massive proteinuria, renal function, and serum albumin improved markedly. This is the first case of adult membranous glomerulonephritis with unilateral lower extremity arterial thrombosis diagnosed by renal biopsy and arteriography. It further confirms the high incidence of thromboembolic complications with membranous nephropathy.

Telemedicine and Clinical Outcomes in Peritoneal Dialysis: A Propensity-Matched Study.

INTRODUCTION: Telemedicine (TM) has shown to provide potential benefits on clinical outcomes in patients with chronic kidney disease but limited evidences published in the peritoneal dialysis (PD) population. This study aimed to explore the long-term effects of TM on the mortality and technique failure. METHODS: The Peritoneal Dialysis Telemedicine-assisted Platform Cohort Study (PDTAP Study) was conducted prospectively in 27 hospitals in China since 2016. Patient and practice data were collected through the doctor-end of the TM app (Manburs) for all participants. TM including self-monitoring records, on-line education materials, and real-time physician-patient contact was only performed for the patient-end users of the Manburs. The primary outcome was all-cause mortality. The secondary outcomes were cause-specific mortality and all-cause and cause-specific permanent transfer to hemodialysis. RESULTS: A total of 7,539 PD patients were enrolled between June 2016 and April 2019, with follow-up till December 2020. Patients were divided into two cohorts: TM group (39.1%) and non-TM group (60.9%). A propensity score was used to create 2,160 matched pairs in which the baseline covariates were well-balanced. There were significantly lower risks of all-cause mortality (HR 0.59 [0.51, 0.67], p < 0.001), CVD mortality (HR 0.59 [0.49, 0.70], p < 0.001), all-cause transfer to hemodialysis (0.57 [0.48, 0.67], p < 0.001), transfer to hemodialysis from PD-related infection (0.67 [0.51, 0.88], p = 0.003), severe fluid overload (0.40 [0.30, 0.55], p < 0.001), inadequate solute clearance (0.49 [0.26, 0.92], p = 0.026), and catheter-related noninfectious complications (0.41 [0.17, 0.97], p = 0.041) in the TM group compared with the non-TM group. CONCLUSION: This study indicated real-world associations between TM usage and reduction in patient survival and technique survival through a multicenter prospective cohort.

The Peritoneal Dialysis Telemedicine-assisted Platform Cohort (PDTAP) Study: Design and methods.

OBJECTIVES: The primary objective of the Peritoneal Dialysis Telemedicine-assisted Platform Cohort (PDTAP) Study is to explore potential predictors and their effects on patient survival, technique survival, and the occurrence of infectious and noninfectious complications. DESIGN: The PDTAP study is a national-level cohort study in China. A newly developed PD telemedicine application provided a unique and convenient way to collect multicenter, structured data across units. SETTING: The PDTAP study was underway in 27 hospitals from 14 provinces located at 7 geographical regions (northwest, northeast, north, central, southwest, southeast, and south) in China. PARTICIPANTS: Our study aims to enroll at least 7000 adult patients with end-stage renal disease receiving PD. METHODS: Approval has been obtained through the ethics committees of all hospitals. All participants signed the informed consent form after the center had received ethics board approval in accordance with the Declaration of Helsinki. MAIN OUTCOME MEASURES: Patient survival, technique survival, hospitalization, and the occurrence of infectious and noninfectious complications. CONCLUSIONS: The PDTAP study aims to explore potential predictors and their effects on patient survival, technique survival, and infectious and noninfectious complications using a newly developed PD telemedicine system to collect multicenter, structured data in real-world practice. Substantial and transformable findings in relation to PD practices were expected. This study also developed a national-level infrastructure for further collaboration and ancillary investigation.

Pleural effusion and ascites in extrarenal lymphangiectasia caused by post-biopsy hematoma: A case report.

BACKGROUND: The renal system has a specific pleural effusion associated with it in the form of "urothorax", a condition where obstructive uropathy or occlusion of the lymphatic ducts leads to extravasated fluids (urine or lymph) crossing the diaphragm via innate perforations or lymphatic channels. As a rare disorder that may cause pleural effusion, renal lymphangiectasia is a congenital or acquired abnormality of the lymphatic system of the kidneys. As vaguely mentioned in a report from the American Journal of Kidney Diseases, this disorder can be caused by extrinsic compression of the kidney secondary to hemorrhage. CASE SUMMARY: A 54-year-old man with biopsy-proven acute tubulointerstitial nephropathy experienced bleeding 3 d post hoc, which, upon clinical detection, manifested as a massive perirenal hematoma on computed tomography (CT) scan without concurrent pleural effusion. His situation was eventually stabilized by expeditious management, including selective renal arterial embolization. Despite good hemodialysis adequacy and stringent volume control, a CT scan 1 mo later found further enlargement of the perirenal hematoma with heterogeneous hypodense fluid, left side pleural effusion and a small amount of ascites. These fluid collections showed a CT density of 3 Hounsfield units, and drained fluid of the pleural effusion revealed a dubiously light-colored transudate with lymphocytic predominance (> 80%). Similar results were found 3 mo later, during which time the patient was free of pulmonary infection, cardiac dysfunction and overt hypoalbuminemia. After careful consideration and exclusion of other possible causative etiologies, we believed that the pleural effusion was due to the occlusion of renal lymphatic ducts by the compression of kidney parenchyma and, in the absence of typical dilation of the related ducts, considered our case as extrarenal lymphangiectasia in a broad sense. CONCLUSION: As such, our case highlighted a morbific passage between the kidney and thorax under an extraordinarily rare condition. Given the paucity of pertinent knowledge, it may further broaden our understanding of this rare disorder.

Zinc-Mediated Intermolecular Reductive Radical Fluoroalkylsulfination of Unsaturated Carbon-Carbon Bonds with Fluoroalkyl Bromides and Sulfur Dioxide.

A versatile and general zinc-mediated intermolecular reductive radical fluoroalkylsulfination of unsaturated C-C bonds has been developed using readily available fluoroalkyl bromides and 1,4-diazabicyclo[2.2.2]octane-bis(sulfur dioxide) adduct (DABSO) with wide substrate scope and excellent functional group tolerance. Sulfur dioxide anion radical generated in situ from the reduction of sulfur dioxide with zinc may be involved in the reaction mechanism.

Predicting risk of pulmonary infection in patients with primary membranous nephropathy on immunosuppressive therapy: The AIM-7C score.

AIM: Pulmonary infection (PI) is the leading cause of death in patients with primary membranous nephropathy on immunosuppressive therapy. A rating score was thus developed to foresee the risk of PI in such patients. METHODS: We reviewed the charts of the pertinent patients treated during the past 3 years either with (n = 29) or without PI (n = 304). Clinical and laboratory data, the usage of cyclosporin A (CysA), and occurrence of PI were recorded. Cox regression analysis and receiver operating characteristic (ROC) curve were respectively used to identify the risk factors and assess their clinical relevance. RESULTS: The incidence of PI was 8.7% at 82.1 ± 20.9 days after the initiation of CysA regimen with a male predominance superimposed on smoking. Factors associated with PI were immunoglobulin G titer (hazard ratio = 4.56, 95% confidence interval = 2.31-8.95), plasma CysA concentration (3.71, 1.87-6.18), serum creatinine level (2.57, 1.31-5.82), CD4+ /CD8+ ratio (2.36, 1.26-6.06) and plasma albumin content (1.53, 1.05-3.25). These five factors, along with the male gender and smoking status, were granted different ratings after examined by the ROC curve and constituted the anticipating pulmonary infection in primary membranous nephropathy receiving CysA (AIM-7C) score. Accordingly, the respective percent composition of the infection and non-infection group was 0, 11.1%, 72.2%, 16.7% and 91.7%, 8.3%, 0, 0 in the order of low, moderate, high and utmost risk. Furthermore, eight new cases of PI were successfully predicted. CONCLUSION: Our AIM-7C score may therefore help to predict the onset and facilitate the prevention of PI, a potentially life-threatening complication of the immunosuppressive therapy.

Kidney injury molecule-1 expression in IgA nephropathy and its correlation with hypoxia and tubulointerstitial inflammation.

Tubulointerstitial injury plays an important role in the development and progression of chronic kidney disease (CKD). Kidney injury molecule (KIM)-1 is induced in damaged proximal tubules in both acute renal injury and CKD. However, the dynamics of KIM-1 in CKD and effects of KIM-1 expression on disease progression are unknown. Here, we aimed to determine the associations between tubular KIM-1 expression levels, renal function, and inflammation in CKD. The relationships between levels of KIM-1 and clinicopathological parameters were analyzed in patients with progressive and nonprogressive IgA nephropathy. KIM-1 expression was increased in patients with IgA nephropathy, and its expression was significantly correlated with the decrease of renal function. KIM-1 was particularly evident at the site with reduced capillary density, and KIM-1-positive tubules were surrounded by infiltrates of inflammatory cells. Using in vitro cell models, we showed that cellular stressors, including hypoxia, induced KIM-1 expression. KIM-1-expressing cells produced more chemokines/cytokines when cultured under hypoxic conditions. Furthermore, we showed that tubular cells with KIM-1 expression can regulate the immune response of inflammatory cells through the secretion of chemotactic factors. These data suggest that KIM-1-expressing epithelial cells may play a role in the pathogenesis of tubulointerstitial inflammation during chronic renal injury through the secretion of chemokines/cytokines.

[Effects of erigeron injection on renal interstitial fibrosis in rats].

OBJECTIVE: To investigate the effect and mechanism of Erigeron Injection (EI) on renal interstitial fibrosis in rats. METHODS: Unilateral ureteral obstruction (UUO) model rats were taken as the subject of study. Thirty-six Sprague-Dawley rats were randomly divided into the control group (A), the UUO model group (B) and the treatment group (C) treated with intraperitoneal injection of EI 5 mL/kg per day from 24 h before to 9 days after the operation. On the 10th day of UUO, rats were killed and their kidneys were processed to paraffin sections with HE, PAS and picro-sirius-red staining. The pathological change of renal tubular interstitial tissue and relative cortical/interstitial volume (C/I) as well as the relative content of collagen (RC) were observed by light microscope. The expression of transforming growth factor beta1 (TGF-beta1), alpha-smooth muscle actin (alpha-SMA) and collagen I in the renal mesenchyma were examined by immunohistochemistry. RESULTS: Marked renal interstitial fibrosis changes were found in Group B and C, but the changes were milder in Group C. C/I and RC were higher in Groups B and C as compared with those in Group A (P < 0.01), but they were much lower in Group C than in Group B (P < 0.01). The expression of TGF-beta1, alpha-SMA and collagen I were higher in Group B and C than those in Group A (P < 0.05), but they were lower in Group C than in Group B (P < 0.05). CONCLUSION: EI could ameliorate renal interstitial fibrosis in rats, which might be partially realized by down-regulating the expression of TGF-beta1 to prevent the renal epithelial cell differentiation and reducing the synthesis of collagen I.