Clinical nephrology最新文献

Introduction: The etiology and pathogenesis of idiopathic nephrotic syndrome (INS) in children remains incompletely understood. We investigated correlations of blood concentrations of eosinophilic cationic protein (ECP), some vitamins, and anti-nephrin antibodies with disease activity of INS in Slovenian children.

Materials and methods: In this prospective, single-center study, we took sequential blood samples from children with INS at disease onset or relapse (before corticosteroid (CS) treatment), at time of remission, and after discontinuation of CS treatment, whenever feasible. We performed the quantitative detection of anti-nephrin antibodies in patients serum with enzyme-linked immuno-sorbent assay, blood concentration measurements of ECP and vitamins with standard laboratory methods and statistical analysis with ANOVA.

Results: We included 17 children with INS (15 boys and 2 girls). We detected statistically significantly highest ECP concentrations at disease onset or relapse, lowest vitamin E concentrations in remission after CS treatment and highest vitamin A concentrations at time of remission achievement. We also detected decreased levels of vitamin D at times of disease onset, relapse and remission achievement. However, we did not detect anti-nephrin antibodies in any serum sample.

Conclusion: We confirmed significant concentration variations of ECP and vitamins E, A, and D at different stages of INS disease activity. These findings suggest their potential role in the etiology of INS and make these molecules as candidates for biomarkers of disease activity. We did not confirm the pathogenic role of anti-nephrin antibodies in our pediatric population.

Introduction: The Mediterranean diet (MD) offers numerous health benefits, including improvements in cardiovascular health, cognitive function, and reduced inflammation. Its role in patients with chronic kidney disease (CKD), particularly those undergoing peritoneal dialysis (PD), remains understudied, but attractive. This study evaluated achieved adherence to the MD, impact on dietary fiber intake, and serum uremic toxins in PD patients.

Materials and methods: An interventional randomized pilot study was conducted on 21 PD patients, randomized into intervention (MD diet counseling) and control groups (standard diet). Dietary intake, fiber consumption, serum potassium, phosphate and serum uremic toxins (trimethylamine-N-oxide (TMAO), p-cresyl sulfate (pCS), and indoxyl sulfate (IS)) were measured before and after a 4-week intervention. Dietary adherence was assessed using the Mediterranean Diet Adherence Screener (MEDAS). Statistical analyses compared the changes between groups.

Results: Adherence to the principles of MD significantly improved in the intervention group (MEDAS: 6.6 ± 1.0 to 8.8 ± 1.2, p < 0.001). Dietary fiber intake increased modestly but not significantly (16.7 ± 6.7 g/day to 19.8 ± 7.5 g/day, p = 0.374). Serum levels of uremic toxins showed no significant change, while potassium and phosphate levels remained stable.

Conclusion: The MD counseling improved dietary adherence to the goals of MD without negatively affecting serum electrolyte and phosphate control in PD patients. No significant changes were observed in serum uremic toxin levels or dietary fiber intake.

Background: Hypervolemia (HV) and arterial stiffness present an important problem for chronic hemodialysis (HD) patients. The most promising methods for evaluating excess fluid are bioelectrical impedance analysis (BIA) and lung ultrasonography with B-line assessment (LUS). The latter is traditionally performed in 28 anatomical locations on the front side of the chest. The study aimed to investigate whether a shorter LUS procedure in 8 locations correlates with other markers of HV and arterial stiffness.

Materials and methods: We performed a single dialysis center observational study in adult chronic HD patients. Patients had to be without active malignancy, infection, chronic atrial fibrillation, carotid stenosis, severe aortic stenosis, or peripheral artery disease. We performed predialysis blood pressure measurements, LUS on 8 predefined locations, BIA, carotid-femoral pulse wave velocity (cfPWV) assessment, and laboratory values of the N-terminal prohormone of brain natriuretic peptide.

Results: 19 patients were included, 7 male (36.8%). The median age of the patients was 71 years (IQR (60 - 74)), the median dialysis vintage was 51 months (IQR (27 - 87)). We found a statistically significant positive correlation between LUS and overhydration measured by BIA (r_s= 0.697; p < 0.001), LUS and intracellular water measured by BIA (r_s= 0.478; p = 0.038), and between LUS and extracellular water measured by BIA (r_s= 0.462; p = 0.046). Furthermore, we also found a statistically significant negative correlation between LUS and cfPWV (r_s= -0.539; p = 0.026).

Conclusion: LUS in 8 locations is associated with markers of HV in HD patients, correlating positively with BIA measurements. Its correlation with cfPWV should be further investigated.

Introduction: Metabolic health refers to the proper functioning and balance of metabolic processes in our bodies. The metabolism of carbohydrates, lipids, and proteins has a direct impact on the cardiovascular system. Recent advances in pharmacotherapy have introduced several drugs into clinical practice that can improve cardiometabolic health.

Materials and methods: Between September 2023 and March 2024, we systematically collected cardiometabolic data from 800 kidney transplant patients (KTPs) during their routine outpatient visits. These included clinical data - office blood pressure, body weight and height, body mass index (BMI), and waist circumference (WC) - and laboratory data such as high-sensitivity C-reactive protein (hs-CRP), lipid profile, lipoprotein(a) (Lp(a)), glycated hemoglobin (HbA1c), serum urate, serum albumin, and proteinuria from spot urine samples. Patients who required treatment adjustment were selected.

Results: Deviations from the desired values of individual components of the metabolic syndrome (blood pressure, WC, triglycerides, high-density lipoprotein cholesterol, and fasting glucose) were observed in 23 - 61.5% of patients. Elevated hs-CRP levels (5 - 10 mg/L), a known cardiovascular risk factor, were observed in 13.5% of patients. Lp(a) levels exceeded the upper normal limit (> 500 mg/L) in 17% of patients. Only a small proportion of patients with moderate to advanced kidney disease - 13% and 23.6%, respectively - had low-density lipoprotein cholesterol levels within the reference range.

Conclusions: Between 23% and 61.5% of patients failed to meet target values for individual components of metabolic health. The largest deviation (61.5%) was observed in WC among women. WC and waist-to-height ratio are two simple and reliable parameters for assessing metabolic status.

Introduction: Solid organ transplant patients require appropriate immunosuppression to sufficiently control the allorecognition of the graft. Two tests, the QuantiFERON Monitor (QFM) and the Torque teno virus load (TTVL) provide an option to monitor the strength of immunosuppression.

Materials and methods: TTVL and QFM were simultaneously determined in kidney transplant patients. Clinical data, microbiological and histopathological findings were collected from the patients' medical records.

Results: 128 TTVL and QFM values were quantified in 107 patients. 69 patients (54%) had recurrent infections in the previous 6 months, 19 (15%) had malignancies, 47 (37%) had a recent kidney biopsy and among them 17 (36%) had histologically proven graft rejection. Results showed that there was no significant correlation between TTVL and QFM (ρ = -0.169, p = 0.061). In patients with histologically proven rejection, TTVL was significantly lower than in patients without rejection (3.64 ± 2.45 vs. 5.02 ± 1.67 log₁₀ copies/mL, p = 0.026), but there was no difference between the groups in QFM (1.63 ± 0.67 vs. 1.55 ± 0.80 log₁₀ IU/mL, p = 0.735). Patients with known malignancy had lower TTVL compared to patients without it (p = 0.041). No statistically significant difference was observed in TTVL and patients with or without infections (p = 0.278). QFM was not different in patients with or without infection or malignancy.

Conclusion: TTVL as an immune marker was associated with transplant rejection. There were no clinically significant associations between QFM and rejection and TTVL or QFM with infections and malignancies. Further prospective studies should be performed to confirm these results.

Introduction: We assessed the use of resorbable extracellular bio-matrix in vascular access surgery.

Materials and methods: A retrospective analysis was made of procedures where a resorbable extracellular bio-matrix was used for the construction or reconstruction of an arteriovenous (AV) fistula. A tubular shape of a certain length and diameter was made from sheets of resorbable bio-matrix (CorMatrix), which was then incorporated into AV anastomosis. Puncturing for hemodialysis began 8 - 10 weeks after construction.

Results: Since 2016, our unit has used resorbable extracellular bio-matrix in 22 patients. We used it as an arterial circuit to the AV fistula vein, a reduction segment in high-flow AV fistulas, to extend the puncture area, as a connecting segment after partial removal of an AV fistula, and to construct the entire AV fistula instead of a graft. All procedures were successful with no significant peri- or post-operative complications. Additional procedures to ensure patency were also successfully performed. Histopathological analysis showed complete vascular differentiation of the bio-matrix resulting in thickening of the wall and narrowing of the lumen.

Conclusion: The use of resorbable extracellular bio-matrix in vascular surgery is safe and feasible. It is recommended to use wider grafts to avoid thrombosis due to narrowing of the lumen. Further research and pre-prepared tubular bio-grafts of different diameters and lengths are needed.

Introduction: Patients with chronic kidney disease (CKD) often experience various nutritional disorders, leading to increased frailty, morbidity, and mortality. The aim of our study was to explore the impact of dietary habits and physical activity on body composition in non-dialysis CKD patients.

Materials and methods: This cross-sectional study included 199 non-frail CKD patients (stages 1 - 5) from the University Medical Center Ljubljana. Participants completed a food frequency questionnaire, and anthropometric measurements were collected. Body composition was assessed using bioelectrical impedance analysis (BIA), and muscle strength was evaluated with handgrip dynamometry.

Results: Central obesity was present in 79.9% of participants, and obesity based on body mass index (BMI) was found in 26.6%. Elevated fat mass was observed in 58.3% of patients. Sarcopenia was identified in 1%, and sarcopenic obesity in 0.5%. Based on the Global Leadership Initiative on Malnutrition (GLIM) criteria, 11.6% of patients were malnourished. Dietary analysis revealed too frequent intake of refined carbohydrates, red meat, and sweets, while intake of fruits and vegetables was not often enough. Dietary habits were suboptimal, with no significant differences between individuals with normal waist circumference and BMI and those with central obesity and elevated BMI. However, a significant difference was observed in physical activity, with those having central obesity engaging in less physical activity.

Conclusion: Central obesity was the most prevalent nutritional disorder in non-frail CKD patients that was markedly more prevalent than obesity defined by BMI. Waist circumference was a more sensitive marker of increased fat mass determined with BIA than BMI. Inadequate dietary habits and insufficient physical activity were major contributing factors to the observed nutritional disorders in our CKD patients and call for long-term lifestyle modifications.

Introduction: The aim of our study was to analyze the results of peritoneal dialysis (PD) treatment in all patients treated with PD in our dialysis center.

Materials and methods: This is a retrospective observational study in which we included all PD patients from the start of PD treatment in 2000 until the end of follow-up on 30 September 2024.

Results: During an observation period of 24 years, 89 patients started PD treatment. Two patients who started PD treatment due to heart failure were excluded. The mean age of the patients was 47 ± 14 years, 61 (70.1%) were men. During PD treatment, 30 (34.5%) patients developed PD-related peritonitis after a median PD duration of 1,174 ± 936 days. During follow-up, 27 (31%) were converted to hemodialysis, 24 (27.6%) received a kidney transplant, 15 (17.2%) patients died during PD treatment, and the remaining 21 patients were still being treated with PD at the end of follow-up. The median duration of PD for all patients was 1,414 ± 1,253 days. Cardiovascular disease (50%) and infection (50%) were the most common causes of death among patients. The comparison between surviving and deceased PD patients showed that surviving patients had a higher baseline serum albumin level (37.7 vs. 34.5 g/L; p = 0.004). The Kaplan-Meier survival analysis showed a worse outcome for diabetics (log rank (Mantel-Cox) = 5.457; p = 0.019).

Conclusion: Cardiovascular disease and infection were common causes of death in PD patients. Peritonitis was the most common cause of PD discontinuation. Diabetics undergoing PD had a poorer survival rate. The average duration of PD treatment was 3.9 years. The average time until the first peritonitis was 3.2 years.

Introduction: Catheter-related bloodstream infections (CBSI) are serious complications in pediatric hemodialysis (HD) patients. We aimed to compare the CBSI rates associated with cuffed and uncuffed central venous catheters (CVC) in small children.

Materials and methods: All HD patients weighing < 15 kg and dialyzed via cuffed CVCs for at least 3 months between March 2016 and March 2022 were included. The CBSI rate was compared to that of a well-matched historical series of our patients before implementing cuffed CVCs.

Results: Three boys and 1 girl (median weight: 14.0 kg) matched the inclusion criteria and received HD using the same type of cuffed CVC. Eleven CBSIs occurred during 4,870 days with cuffed CVCs, yielding a CBSI rate of 2.3/1,000 catheter days, compared to 7.7/1,000 catheter days in our historical series with uncuffed CVCs (p = 0.002). A 70% reduction in the CBSI rate was achieved with cuffed CVCs (p = 0.002). The median catheter survival times for cuffed and uncuffed CVCs were 189 and 53 days, respectively (p = 0.002).

Conclusion: Our results show that cuffed CVCs are associated with reduced CBSI rates and improved catheter longevity compared to uncuffed ones in small children.

Introduction: Catheter-related infections significantly increase the morbidity and mortality of dialysis patients. Our study aimed to assess the incidence of catheter-related infections in tunneled central venous catheters at our dialysis center.

Materials and methods: We retrospectively analyzed the incidence of catheter-related bloodstream infections (CRBSI) and tunnel infections in patients with a tunneled central venous catheter inserted at Trbovlje General Hospital between January 2015 and August 2024. The indication for catheter insertion was a reduced left ventricular ejection fraction (< 30%), polymorbidity with a short life expectancy (< 1 year), or a condition of the vascular system that made construction of an arteriovenous fistula/graft impossible.

Results: We included 344 patients (average age 73 ± 13 years, 49% men). In all patients, we inserted a tunneled central venous catheter with a symmetrical tip in a retrograde manner (64% through the right jugular vein). During the observed period, there were 16 cases of CRBSI (after 10 (IQR 5 - 14) months) and 4 cases of catheter tunnel infection (after 9 (IQR 4 - 16) months). In all cases of CRBSI, the catheter was replaced. In the case of catheter tunnel infections, the outer part of the catheter was replaced, and the tunnel infection was treated locally. The incidence of CRBSI was 0.09/1,000 catheter days.

Conclusion: The incidence of CRBSI in our cohort was low, likely due to the implementation of preventive protocols for insertion and maintenance of tunneled central venous catheters.