Clinical nephrology最新文献

Introduction: Brown tumors are benign lesions caused by hyperparathyroidism and characterized by increased osteoclast activity and mass effect, which can lead to paraplegia when the spine is involved. Secondary hyperparathyroidism is common in patients on long-term hemodialysis therapy.

Case report: We report the case of a 48-year-old man on regular dialysis who presented with leg weakness as well as back pain and was diagnosed with secondary hyperparathyroidism and thoracic spine tumor. Since the spinal cord was compressed, T12 mass excision combined with spinal canal decompression was performed under general anesthesia. Post-operative pathology demonstrated abundant fibrovascular tissue and osteoclast-like multinucleated giant cells with hemorrhage and hemosiderin pigment deposition. The patient was diagnosed with brown tumor. Following operation, the patient recovered well. He remains on regular hemodialysis with follow-ups and unaffected activities 10 years later.

Discussion: In dialysis patients with combined spinal tumors, brown tumors should be considered. For patients presenting with symptoms of spinal cord compression, surgical resection can lead to a favorable prognosis.

Objective: Antineutrophil cytoplasmic antibody (ANCA) associated vasculitis (AAV), a multisystem autoimmune disorder, deteriorates small vessels. Kidney involvement occurs in most affected patients and is the most common cause of rapidly progressive glomerulonephritis (RPGN). Rituximab (RTX), an anti-CD20 antibody, has been used in the induction and maintenance therapy of AAV as a non-inferior alternative to cyclophosphamide. Administration of 4 once-weekly doses of 375 mg/m² is the common dose in remission induction therapy, referred to as a conventional regimen. Recently, it was shown that the cumulative complete remission (CR) rates did not differ between low-dose RTX (2 once-weekly doses of 375 mg/m²) and the conventional RTX regimen. We aimed to explore the effect of the B cell-driven RTX dosing regimen.

Case reports: Herein, we reported B cell-driven reduced-dose RTX therapies in a 71-year-old male de novo patient (case 1) and a 60-year-old female patient (case 2). Case 1, de novo diagnosed based on kidney biopsy, received 3 once-semimonthly doses of 300 mg RTX as induction therapy. Case 2, who was clinically diagnosed with ANCA-associated renal vasculitis 4 years before receiving treatment at our hospital, accepted 4 once-monthly doses of 300 mg RTX as induction therapy. Further dosages were dependent on peripheral CD19+ B-cell levels.

Results: During the course of treatment, peripheral B-cell counts of both patients turned 0, and symptoms of both patients improved, complete remission occurred in case 1, with a Birmingham vasculitis activity score (BVAS) of 0.

Conclusion: B cell-driven reduced-dose RTX might be also effective in induction therapy for AAV. Further study is warranted to confirm the efficacy, safety, and risk of relapse of a reduced-dose RTX regimen.

Background: Among hemodialysis patients, left ventricular hypertrophy (LVH) is a prevalent cardiac abnormality. The uremic toxin indole-3-acetic acid (IAA) is elevated in uremia patients, but the connection between IAA and LVH in individuals undergoing hemodialysis remains uncertain. Hence, the objective of this research was to examine the correlation between blood IAA levels and LVH in individuals undergoing hemodialysis.

Materials and methods: In total, 205 individuals undergoing hemodialysis were chosen and categorized into two groups, with (143 patients) and without LVH (62 patients). Patient clinical data were collected, and serum creatinine, calcium, phosphorus, hemoglobin, and IAA levels were measured.

Results: Compared to the non-LVH group, the LVH group had higher IAA and serum phosphorus but lower hemoglobin. The serum IAA concentration was positively correlated with both left ventricular mass (LVM) and left ventricular mass index (LVMI) but negatively correlated with both left ventricular ejection fraction (LVEF) and the ratio of left ventricular transmitral early peak flow velocity to left ventricular transmitral late peak flow velocity (E/A). Logistic regression analysis indicated that increased IAA levels are a risk factor for LVH and are not influenced by other factors. In addition, we exposed primary neonatal cultured mouse cardiomyocytes to varying concentrations of IAA in a controlled environment. Cardiomyocyte hypertrophy was induced by IAA in a concentration-dependent manner.

Conclusion: Serum IAA is correlated with alterations in both the function and structure of the left ventricle. The serum IAA concentration is an independent risk factor for LVH. IAA may be a novel biomarker of LVH in hemodialysis patients.

Introduction: Kidney dysfunction is a frequent complication of multiple myeloma (MM) and is associated with worse survival outcomes. Despite its prevalence, the prognostic value of long-term kidney function decline remains insufficiently explored. This study aimed to investigate the impact of the estimated glomerular filtration rate (eGFR) slope on survival in patients with MM.

Materials and methods: A retrospective cohort study was conducted on 43 patients with MM treated at the University Medical Center Maribor between 2015 and 2020, with a minimum follow-up of 1 year. Kidney function was assessed quarterly using eGFR. Kaplan-Meier analysis and Cox regression were applied to evaluate the association between eGFR slope and overall survival.

Results: The median baseline eGFR was 52.8 mL/min/1.73m² (interquartile range: 35.2 - 78.1), with 39.5% of patients classified as having stage 3 or worse chronic kidney disease. We observed an association between faster annual eGFR slope decline and increased mortality (log-rank; p < 0.001). Cox regression confirmed eGFR slope as an independent predictor of mortality (hazard ratio = 1.121, 95% confidence interval: 1.069 - 1.174, p < 0.001). Additional prognostic factors included a lower platelet count.

Conclusion: Kidney function decline is an independent prognostic factor in patients with MM. Regular monitoring and early nephrology intervention may help mitigate its impact. Future research should focus on targeted strategies to slow kidney function deterioration and improve patient outcomes.

Rituximab (RTX) is the anti-CD20 monoclonal antibody that has been used as the first-line therapy for primary membranous nephropathy (PMN) in recent years. However, the optimal dosing regimen and timing of RTX, or combination with other immunosuppressants, especially in patients with extremely high titers (> 1,000 RU/mL) of anti-PLA2R antibody (aPLA2R), are unclear at present. This report describes the case of a 70-year-old PMN patient with extremely high aPLA2R titer who failed to respond to very high doses of RTX. We also discuss the possible reasons for treatment failure.

Introduction: Minimal change disease (MCD) is one of the causes of nephrotic syndrome (NS) in adults. Recently, anti-nephrin antibodies have been detected in a certain subset of patients with MCD, supporting the proposed autoimmune etiology and appearing to be markers of disease activity. Despite their diagnostic and prognostic potential, the use of anti-nephrin autoantibodies in routine clinical practice is not yet widespread. Studies have shown that patients with anti-nephrin-associated MCD have a more fulminant NS and a better response to antibody-depleting therapy than those who are anti-nephrin-negative.

Materials and methods: We report cases of a 79- and a 42-year-old male patient presenting with new-onset NS and acute kidney injury. Both patients had negative immunologic tests, including antibodies against phospholipase A2-receptor (anti-PLA2R) and thrombospondin-7A (anti-THSD7A). Renal biopsy was performed in both patients.

Results: In both cases, light microscopy of kidney samples from thick-needle biopsy showed acute tubular injury attributed to severe proteinuria. Electron microscopy revealed diffuse (90%) effacement of the podocyte foot processes without electron-dense deposits. Immunofluorescence presented discrete intracytoplasmic IgG podocyte deposits with a high probability of MCD due to anti-nephrin autoantibodies. In addition to therapy with angiotensin convertase inhibitors, calcium channel blockers, and furosemide, we started treatment with low-dose oral glucocorticoids and mycophenolic acid (case 1) or oral glucocorticoids alone (case 2) depending on patients' comorbidities. We administered rituximab, resulting in a fast and complete resolution of proteinuria and improvement of kidney function.

Conclusion: Anti-nephrin autoantibodies have been detected in a subgroup of patients with MCD supporting the autoimmune etiology of the disease. Targeted anti-B-cell therapy with rituximab is an additional therapeutic option in patients with relapsing or treatment-resistant disease, or drug-related adverse effects to standard therapy.

Introduction: This study evaluated the effectiveness and safety of an add-on treatment with finerenone as combination therapy in patients with diabetic kidney disease (DKD), an area where real-world data is limited.

Materials and methods: We retrospectively evaluated patients with DKD treated with sodium-glucose cotransporter 2 (SGLT-2) inhibitors and add-on finerenone, to assess the effectiveness and safety of the combination therapy (data collected between June 2021 and October 2024). Outcomes included changes in urinary albumin-to-creatinine ratio (UACR), protein-to-creatinine ratio (UPCR), estimated glomerular filtration rate (eGFR), and serum potassium before and after finerenone initiation.

Results: Among 23 patients (mean age 72 ± 7; 17 male) on SGLT-2 inhibitors, 21 (91%) also received renin-angiotensin system (RAS) inhibitors and 9 (39%) glucagon-like peptide-1 (GLP-1) receptor agonists. Addition of finerenone significantly reduced UPCR from 0.52 (0.18 - 1.35) to 0.41 (0.16 - 1.78) g/g (p = 0.046), a median decrease of 35% (IQR -53 to -8). UACR showed a reduction trend from 285 (36 - 1,020) to 266 (57 - 1,006) mg/g (p = 0.15), with a median decrease of 36% (IQR -65 to +14). Kidney function remained stable with a small non-significant decline in eGFR (45 ± 22 to 44 ± 21 mL/min/1.73m²; -4% ± 13%; p = 0.13). Serum potassium increased slightly but significantly (4.3 ± 0.5 to 4.5 ± 0.4 mmol/L; p = 0.045), with 1 mild hyperkalemia case (5.6 mmol/L) and no treatment discontinuations.

Conclusion: In this real-world cohort, the renoprotective combination therapy with added finerenone was associated with a further reduction in albuminuria and proteinuria. The treatment was well tolerated with a minimal increase in potassium levels and generally stable renal function.

Aim: The risk of infection with COVID-19 in hemodialysis (HD) patients is higher compared to the general population. Additionally, HD patients are at higher risk of developing post-COVID-19 infection sequelae. However, this has not been thoroughly investigated. Therefore, we aimed to study the impact of COVID-19 on nutritional status and psychological health in HD patients 6 months following recovery.

Materials and methods: We recruited HD patients who were proven to be infected with COVID-19 and received treatment at two HD units in two institutions between April 2022 and December 2022. Additionally, we enrolled a group of age- and sex-matched HD patients who had not previously been infected with COVID-19 or received vaccination. Nutritional status was assessed using malnutrition inflammation score (MIS), while psychological health was assessed using online questionnaires. The Patient Health Questionnaire 9 (PHQ 9) was employed to assess symptoms of depression, the Generalized Anxiety Disorder 7 (GAD 7) was used to identify anxiety disorders, the Patient Health Questionnaire 15 (PHQ 15) was utilized to measure somatic symptoms, and the Insomnia Severity Index (ISI) was used to measure insomnia.

Results: A total of 60 subjects (30 patients and 30 controls) were assessed in the study. We found statistically significant differences between patients and controls regarding the MIS (median score (interquartile range (IQR)); 11 (9 - 12) and 5.5 (5 - 7), respectively), PHQ 15 (median score (IQR); 17.5 (15 - 19) and 9 (6 - 11), respectively), PHQ 9 (median score (IQR); 17 (13 - 19) and 5 (7 - 8), respectively), GAD 7 (median score (IQR); 14 (11 - 16) and 6 (4 - 8), respectively), and ISI (median score (IQR); 20 (15 - 22) and 8 (7 - 11), respectively), with p < 0.001 for all scores.

Conclusion: COVID-19 has long-term effects on the psychosocial health of HD patients and may lead to a higher incidence of malnutrition 6 months post recovery.

Background and objectives: Chronic kidney disease (CKD) is associated with increased cardiovascular risk, which may be mediated by vascular calcification. Based on evidence that bisphosphonates inhibit vascular calcification, we hypothesized use of bisphosphonates in CKD would be associated with lower incident cardiovascular disease (CVD), CVD-related mortality, and all-cause mortality.

Materials and methods: This was a longitudinal observational study including 2,593 Framingham Offspring participants. We used propensity score-adjusted Cox regression models to determine the association between bisphosphonate use and outcomes: time to incident CVD, time to CVD-related mortality, and time to all-cause mortality. The data were stratified by presence or absence of CKD, defined as estimated glomerular filtration rate < 60 mL/min/1.73m². The propensity score included age, sex, hypertension, smoking status, diabetes, total cholesterol, high-density lipoprotein, and self-reported history of fracture.

Results: In unadjusted and propensity score-adjusted analyses, those with CKD using bisphosphonates had a trend toward increased incident CVD risk (adjusted hazard ratio (HR) 1.66 (95% CI, 93 - 2.97)) compared to those with CKD not using bisphosphonates. Those with CKD using bisphosphonates also had increased risk of cardiovascular mortality in the propensity score-adjusted model (adjusted HR 2.20 (95% CI, 1.12 - 4.32)). There was no significant association between bisphosphonate use and all-cause mortality in participants with CKD. Among individuals without CKD, bisphosphonate use was significantly associated with an increase in all-cause mortality in the propensity-score adjusted analysis (adjusted HR 1.59 (95% CI, 1.27 - 1.98)). However, there was no significant association between bisphosphonate use and incident CVD events (adjusted HR 0.85 95% CI, 0.63 - 1.16) or CVD-related death (adjusted HR 0.70 (95% CI 0.36 - 1.37) in those without CKD.

Conclusion: Contrary to our hypothesis, bisphosphonate use was associated with a trend toward increased incident CVD and a two-fold higher risk of CVD mortality in CKD.

Introduction: Hypocalcemia is a common and clinically significant side effect of etelcalcetide therapy. The aim of this study was to evaluate the utility of ionized calcium (iCa) measurements with a point-of-care ionometer compared to albumin-corrected total calcium and to assess the incidence of hypocalcemia in patients receiving etelcalcetide therapy using pre-dialysis iCa values.

Materials and methods: This was a phase IV, non-interventional, prospective, single-arm, observational study. A total of 20 chronic hemodialysis patients were included in the study. The iCa concentration was determined before dialysis using a point-of-care ionometer (GEM Premier 3000) at the patient's bedside. Hypocalcemia was defined by a pre-dialysis iCa concentration of less than 0.90 mmol/L.

Results: Pre-dialysis corrected total calcium and iCa decreased over time during treatment with etelcalcetide. A statistically significant linear association was observed between point-of-care iCa and albumin-corrected calcium (r = 0.532, p = 0.019; R² = 0.283). Visual comparisons generally showed parallel behavior, but only a moderate correlation. Of 240 iCa values measured, 3 cases (1.25%) were < 0.90 mmol/L and 20 cases (8.3%) were between 0.90 and 0.96 mmol/L.

Conclusion: Our results highlight the value of direct iCa monitoring as a practical and sensitive tool for detecting hypocalcemia and guiding etelcalcetide therapy. Bedside measurement enabled timely dialysate calcium adjustments, preventing clinically significant hypocalcemia and treatment discontinuation. Point-of-care iCa monitoring offers a safer, more responsive strategy for optimizing calcium management in hemodialysis patients.