Clinical nephrology最新文献

Systemic COVID-19 disease is associated with a variety of organ involvement in infected patients. A rarely reported complication is the induction of complement-mediated thrombotic microangiopathy (TMA). TMA is an extremely rare pathological condition that results in thrombosis in capillaries and small arterioles, due to an endothelial injury. It is often combined with thrombocytopenia, Coombs-negative hemolytic anemia, and end-organ damage. This case involves a patient who was admitted to our hospital for the purpose of diagnosis and treatment of acute kidney injury (AKIN 3) with severe proteinuria after a preceding SARS-CoV-2 infection. A 77-year-old male patient had COVID-19 pneumonia in January 2021 with the need of high-flow oxygen therapy in the intensive care unit. In March 2021, he was hospitalized again due to elevated serum creatinine levels and proteinuria. The patient exhibited normal vital parameters. A renal biopsy showed severe TMA. A diagnosis of COVID-19-associated TMA was made, and treatment with high-dose glucocorticoid therapy and plasma exchange was initiated. Additionally, therapy with eculizumab was established. Unfortunately, the kidney failure was initially progressive, so that hemodialysis (HD) was temporarily necessary. In May 2021, kidney function recovered to an estimated glomerular filtration rate of ~ 30 mL/min/1.73m² corresponding to chronic kidney disease stage 3bA3 - 4A3. COVID-19-associated TMA is an extremely rare disease. TMA may be a possible long-term complication with the risk of end-stage renal disease if not properly diagnosed and treated.

Aim: BK polyomavirus infection is a challenging complication of renal transplantation. The management is not standardized and is based on reports from transplantation centers' experiences, usually with small sample sizes. Therefore, we aimed to present our countrywide experience with BK virus nephropathy (BKVN) in renal transplant recipients.

Materials and methods: Our study was carried out with the participation of 30 transplantation centers from all regions of Turkey. Only cases with allograft biopsy-proven BKVN were included in the study.

Results: 13,857 patients from 30 transplantation centers were screened, and 207 BK nephropathy cases were included. The mean age was 46.4 ±  13.1 years, and 146 (70.5%) patients were male. The mean time to diagnosis of BK nephropathy was 15.8 ± 22.2 months after transplantation. At diagnosis, the mean creatinine level was 1.8 ±  0.7 mg/dL, and the mean estimated glomerular filtration rate was 45.8 ± 19.6 mL/min/1.73m². In addition to dose reduction or discontinuation of immunosuppressive drugs, 18 patients were treated with cidofovir, 11 patients with leflunomide, 17 patients with quinolones, 15 patients with intravenous immunoglobulin (IVIG), 5 patients with cidofovir plus IVIG, and 12 patients with leflunomide plus IVIG. None of the patients receiving leflunomide or leflunomide plus IVIG had allograft loss. During follow-up, allograft loss occurred in 32 (15%) out of 207 patients with BK nephropathy.

Conclusion: BKVN is still a frequent cause of allograft loss in kidney transplantation and is not fully elucidated. The results of our study suggest that leflunomide treatment is associated with more favorable allograft outcomes.

Background: It is still uncertain whether vitamin intake is associated with better quality of life in hemodialysis patients. This study aims to assess the association between the quantity of supplemented vitamins and health-related quality of life (HRQoL) in this population.

Materials and methods: This cross-sectional study included all patients on chronic hemodialysis from three units. Vitamins and micronutrients assessed were B1, B6, B12, C, D, folic acid, menaquinone, carnitine, zinc, and coenzyme Q10. Quality of life scores included the 8 domains of SF-36 and the 11 domains of the Kidney Disease Quality of Life (KDQOL). Bivariate analysis compared two groups of patients divided based on the median of vitamin intake. Spearman Rho test assessed the correlation between number of vitamins and different dimensions of HRQoL.

Results: A total of 183 patients were included. Median number of vitamins supplemented was 2 (1,3); 112 patients had an intake of ≤ 2 vitamins, and 71 patients were taking > 2 vitamins. There was a significant association between higher vitamin intake and the burden of kidney disease that remained significant in the multivariable analysis (p = 0.03), but no correlation between the number of vitamins (0 - 13) and different HRQoL scores. Sub-analyses of each category of vitamins showed no significant difference in HRQoL scores except for Vitamin B and staff encouragement (p = 0.01) and for multivitamins and quality of social interaction (p = 0.03).

Conclusion: A higher number of vitamins in hemodialysis patients is associated with an increased perception of the burden of kidney disease. Interventional studies are needed to assess whether selective vitamin supplementation in case of deficiencies is associated with better quality of life.

Mixed cryoglobulinemia is a small vessel vasculitis associated with viral infections, mainly hepatitis C virus, however, other important causes include lymphoproliferative and autoimmune disorders. Influenza vaccine-induced cryoglobulinemia has been rarely reported. A 68-year-old male presented on three occasions following influenza vaccination with purpuric rash and lower extremities swelling. His lab work showed mixed cryoglobulins. On his most recent presentation, in addition to the purpura, he presented with thrombocytopenia and nephritic syndrome. A kidney biopsy showed endocapillary proliferative glomerulonephritis with organized deposits, consistent with mixed type cryoglobulinemic glomerulonephritis. The patient was treated with rituximab infusion with progressive improvement of the acute kidney injury (AKI) and complete recovery. It is unclear why cryoglobulins are produced as a response to a vaccination, but this association is important to be aware of for prompt monitoring and treatment.

Fibrillary glomerulonephritis (FGN) is a rare glomerular disease defined by the presence of microfibrils that deposit within the glomeruli. While initially thought to be idiopathic, FGN is now recognized to be associated with infection, malignancies, and autoimmune disorders. We describe a case of biopsy-proven FGN in a patient with seropositive rheumatoid arthritis (RA) and provide a review of the literature regarding the association of FGN with RA.

Aims: The mortality rate for -COVID-19 infection varies significantly depending on age and comorbidities but remains high in hospitalized patients overall. Several retrospective studies have identified patients with end-stage kidney disease (ESKD) to be at increased risk. The objective of this study was to study in-hospital outcomes of ESKD patients at an academic medical center and identify characteristics that place them at a higher risk for in-hospital mortality.

Materials and methods: A retrospective chart review was conducted including adult patients (≥ 18 years old) admitted to Loma Linda Medical Center for COVID-19 infection with a previous diagnosis of ESKD. Patients with prior kidney transplants were excluded. The main outcome of this study was the rate of in-hospital mortality.

Results: 21 of the 91 patients died with a mortality rate of 23%. Age, D-dimer > 0.4 µg/mL, ejection fraction less than 50%, and ferritin > 300 ng/mL were predictors for mortality in unadjusted univariate analysis. Adjusted multivariable analysis demonstrated that only an ejection fraction of less than 50% was associated with increased mortality risk.

Conclusion: Cardiovascular disease is the leading cause of mortality for ESKD patients and also places them at increased risk of mortality in the setting of severe COVID-19 infection.

Background: Hyperkalemia is a common complication of chronic kidney disease (CKD). This study aims to investigate the efficacy and safety of sodium zirconium cyclosilicate and calcium polystyrene sulfonate in reducing potassium in patients with acute and severe hyperkalemia in CKD who are not undergoing dialysis.

Materials and methods: A retrospective real-world study was conducted among 73 patients with non-dialysis chronic kidney disease who were hospitalized in the First Affiliated Hospital of Chengdu Medical College from June 2020 to June 2022. 33 patients treated with sodium zirconium cyclosilicate were categorized as SZC group, and the other 40 patients treated with calcium polystyrene sulfonate were categorized as CPS group. Serum potassium, serum sodium, magnesium, calcium, and phosphorus levels were examined. Adverse reactions were recorded during medication.

Results: Significantly decreased serum potassium was observed in both groups, whereas the potassium reduction was higher in the SZC group than in the CPS group at 2, 4, 24, and 48 hours after medication while there was no statistically significant difference in the serum potassium level between the two groups at 72 hours. For those people whose initial potassium exceeded 6 mmol/L, the potassium reduction was more obvious in the SZC group than in the CPS group at 2 and 4 hours after medication. The control rate of hyperkalemia in the SZC group was significantly higher than in the CPS group at 4, 24, and 48 hours. No distinct change was observed in serum sodium, calcium, magnesium, and phosphorus before and 72 hours after medication. No severe adverse reactions occurred.

Conclusion: Sodium zirconium cyclosilicate has a more obvious effect on reducing potassium particularly for those patients with moderate to severe hyperkalemia who need rapid potassium reduction.

Wilson disease is a rare autosomal recessive genetic disorder of copper metabolism that leads to copper accumulation and subsequent organ dysfunction. While classically considered a condition that primarily affects the liver and nervous system, Wilson disease and its treatments can also result in a wide range of kidney complications as well. We present the case of a 31-year-old female with a longstanding (> 10 year) history of Wilson disease who developed acute-onset nephrotic syndrome including heavy proteinuria, hypoalbuminemia, and edema after being transitioned from zinc to D-penicillamine for copper chelation therapy. Following simple cessation of D-penicillamine (and without any immunosuppressive therapies including corticosteroids), the nephrotic syndrome showed remarkable improvement including complete remission within several months. This review comprehensively summarizes the kidney complications associated with Wilson disease and its treatments.

Background: Catheter malfunctions are associated with reduced blood flow and interrupted dialysis during hemodialysis.

Aim: This meta-analysis aimed to determine whether the use of urokinase to lock hemodialysis catheters can maintain their patency and prevent catheter-related bloodstream infections (CRBSIs).

Materials and methods: The PubMed, Cochrane Library, Web of Science, Embase, and Chinese medical databases were searched for controlled trials of hemodialysis catheter locking using urokinase from database inception until July 15, 2021. The primary outcome was catheter malfunction, and the secondary outcomes were the peak catheter blood flow rate (Qb) and CRBSIs.

Results: Across 16 trials, 1,041 patients were randomized to receive either urokinase/urokinase mixture (treated) or heparin (control) locks once or thrice a week. Locking with urokinase alone or in combination with another substance significantly prevented catheter malfunction. The effect on Qb was significant, with that in the treated group being better than in the control group. Similarly, the incidence of CRBSIs in the treated group was lower.

Conclusion: Urokinase locking maintains catheter patency more effectively than heparin. Prophylactic locking with urokinase or urokinase mixtures reduces incidences of catheter malfunction, which ensures the smooth progression of hemodialysis and reduces patient medical costs. The results of this study have important clinical implications and will provide guidance to medical practitioners globally.