Pediatric Nephrology最新文献

Background: The native kidney biopsy is an important diagnostic procedure in pediatric nephrology. Recent meta-analyses did not find the size of the needle as a risk factor for bleeding complications, but they were predominantly based on adult studies. There are few papers comparing the safety and core adequacy in pediatric native kidney biopsy.

Methods: We present a large single-center retrospective study performed in a tertiary pediatric nephrology center. Data of children who received a real-time ultrasound-guided native kidney biopsy with a 16- or an 18-gauge needle from 2018 to 2024 were analyzed.

Results: Overall, 1040 children (644 boys) were included, with a median age of 10.25 (6.6; 14.23) years. One hundred three (9.9%) patients experienced bleeding complications. Perinephric hematoma was reported in 86 (8.3%) cases, gross hematuria in 18 (1.7%), and 3 (0.3%) children required transfusion. Multivariate regression analysis revealed the needle size (OR for 16-gauge 2.06, 95% CI 1.22-3.47, p = 0.007) as a risk factor for complications in the overall cohort and in children under 12 years old. The needle size did not affect complication rates in children aged 12-18 years. Inadequate kidney cores were reported in 37 (4.5%) cases; OR for 18-gauge needles (OR 5.08, 95% CI 1.07-24.21, p = 0.041) was found.

Conclusions: Use of a 16-gauge needle reduces the risk of obtaining an inadequate core in comparison with an 18-gauge. An 18G needle has a safety advantage over a 16G needle in children younger than 12 years. A 16G needle is as safe as an 18G needle and should be used for native kidney biopsy in children older than 12 years.

Background: Accurate glomerular filtration rate estimation (eGFR) is essential for managing pediatric kidney transplant recipients. Given the physiology of pediatric patients receiving adult-donor kidneys, identifying the most appropriate plasma creatinine (PCr)-based formula-pediatric or adult-specific-is crucial.

Methods: This cross-sectional study included pediatric kidney transplant recipients (age 1-18 years) who received adult-donor kidneys. We compared agreement thresholds of various pediatric and adult PCr-based GFR equations with CKiD 2012 combined PCr‒cystatin C (PCr-CystC) equation via intraclass correlation coefficients (ICCs), concordance correlation coefficients (CCCs), total deviation index (TDI), P30 performance metric (P30), Bland-Altman plots, and receiver-operating characteristic (ROC) analysis. Correlation between CKiD under 25 (U25) PCr-CystC and reference CKiD 2012 equation was also evaluated.

Results: One hundred twenty samples were collected from 23 recipients (mean age = 14.2 ± 3.4 years) and donors (mean age = 31.7 ± 10.0 years). Schwartz-Lyon equation demonstrated the highest performance with the reference (ICC = 0.913, CCC = 0.911, TDI = 14.0 mL/min/1.73 m², P30 = 99.2%). U25 (ICC = 0.922, CCC = 0.882, P30 = 93.3%), full age spectrum (FAS)-height (ICC = 0.897, CCC = 0.877, P30 = 96.7%), and Bedside Schwartz equations (ICC = 0.850, CCC = 0.819, P30 = 89.2%) showed comparable performance. Bland-Altman plots revealed proportional bias (p < 0.05), leading to ROC analysis, which identified eGFR < 70 mL/min/1.73 m² for Schwartz-Lyon, U25, and FAS-height, and < 60 mL/min/1.73 m² for Bedside Schwartz as optimal agreement thresholds, beyond which each equation showed increased bias. Subgroup analyses also showed better performance in patients aged 10-18 years. Additionally, U25 PCr-CystC equation showed excellent agreement with the reference (ICC = 0.993, CCC = 0.990, P30 = 100%).

Conclusions: Schwartz-Lyon equation demonstrated the highest performance among PCr-based equations with the reference in pediatric kidney transplant recipients, particularly when eGFR was < 70 mL/min/1.73 m² and in patients aged 10-18 years. U25 PCr-CystC equation showed best overall agreement with the reference and should be preferred where CystC measurement is feasible.

Background: Measures of early postnatal fluid balance may be associated with severe intraventricular hemorrhage (sIVH) and/or death in extremely preterm infants in the first postnatal week.

Methods: A single-center, retrospective cohort study including actively treated inborn infants weighing ≥ 400 g and 22-27 weeks' gestation from 2014-2021. Longitudinal mixed effect models compared daily fluid balance covariates including serum sodium, percent weight change, total fluid intake, urine output, and fluid balance (daily weight - birth weight /birth weight × 100) among infants with and without sIVH or death, during the first seven postnatal days. Multiple regression and machine learning models were developed to predict sIVH and/or death. Variables that were incorporated into the models included measures of fluid balance, gestational age, birth weight, antenatal corticosteroids, multiples, and sex.

Results: We included 932 infants with mean ± SD gestational age of 25w2d ± 11d and birth weight of 746 ± 212 g of whom 195 (20.9%) had sIVH and/or death. Lower percentage weight change (p < 0.001), higher total fluid intake (p = 0.007), higher sodium (p = 0.007), and positive early fluid balance (p < 0.001) were associated with sIVH and/or death even after adjustment for baseline characteristics. The area under the receiver-operating curve (AUC) for regression models predicting sIVH and/or death incorporating baseline characteristics improved after adding fluid balance measures from 0.75 to 0.80, while the AUC for machine learning models improved from 0.72 to 0.84.

Conclusions: In extremely preterm infants, early fluid status measures were associated with risk of sIVH and/or death. The addition of fluid status measures improves the performance of models predicting sIVH and/or death.

Background: Dialytic sodium removal (DSR) is an important parameter of peritoneal dialysis (PD) adequacy. The aim of this study was to report the DSR of children with acute kidney injury (AKI) on a standard acute PD prescription and to compare it to that of children on continuous flow peritoneal dialysis (CFPD).

Methods: A secondary analysis of prospectively collected data was performed from a published randomized controlled crossover trial comparing children on conventional PD and CFPD. The conventional PD prescription used: fill volume 20 mL/kg, glucose 2.5%, dwell time 45-60 min. In this study, we described and compared DSR in 15 children with AKI receiving PD and CFPD. Relative ultrafiltration through small pore (UFSP) was also described and compared.

Results: The median (range) weight and age of patients were 5.8 (2.3-14.0) kg and 6 (0.2-14) months. Approximately 8 h of dialysis was received per patient per modality. Results were then extrapolated and expressed per day. The mean ± SD DSR on conventional PD and CFPD were 2.7 ± 6 and 8.4 ± 10 mmol /kg/day, respectively (P = 0.02). The mean ± SD sodium dialysate to plasma (D/P) ratio on conventional PD and CFPD were 0.94 ± 0.03 and 0.94 ± 0.04 mmol/mmol (P = 1.0). Mean ± SD UFSP to total UF ratios on conventional PD and CFPD were 0.82 ± 0.39 and 0.66 ± 0.51 mL/mL (P = 0.14).

Conclusions: This study adds to the limited data on DSR in children on PD for AKI. CFPD removes more salt compared to conventional PD because of increased ultrafiltration (UF). A high percentage of UF was through small pores in both modalities.

Background: Thrombotic occlusion of permanent double lumen catheters (PDLC) in hemodialysis has traditionally been treated with urokinase (UK), a thrombolytic agent. However, because UK is no longer available, alteplase has been reported as an alternative. In this study, we compared the efficacy and safety of alteplase with those of UK.

Methods: This retrospective analysis included patients undergoing hemodialysis with thrombotic occlusion from May 2014 to February 2025. The drug was administered as a bolus dose into the catheter and allowed to dwell for 60 min. The primary endpoint was the blockage resolution rate after the first thrombolytic agent.

Results: During the study period, 24 patients underwent pharmacological thrombolysis, with a total of 165 procedures performed, including 37 with alteplase and 128 with UK. The median age and weight at the time of thrombotic occlusion were significantly lower in the alteplase group than in the UK group (1.7 vs. 3.9 years and 6.4 vs. 14.4 kg; p < 0.01). The alteplase group had a higher success rate (34/37, 94%) than the UK group (96/128, 75%) (p = 0.038). When the first dose of alteplase was unsuccessful, a second dose successfully cleared the blockage in all instances. No serious adverse effects, such as bleeding events, were observed in either group.

Conclusions: Alteplase may serve as a viable alternative in settings where UK is unavailable. Its bolus administration, established as safe in adults, also appears to be safe in children weighing less than 10 kg, with no serious adverse events observed.

Nephropathic cystinosis is a lysosomal storage disease due to biallelic pathogenic variants in the CTNS gene encoding the cystine transport protein cystinosin. Dysfunction of cystinosin results in the intralysosomal accumulation of the disulfide cystine, which crystallizes in some tissues and damages many parenchymal organs. Fanconi syndrome is the first presenting sign with all the features of generalized proximal tubular dysfunction. The natural history of cystinosis includes multisystem complications, the most prominent being glomerular failure at 9-10 years. If a kidney transplant prolongs life, other complications occur, with variable frequencies. Some of the most common are hypothyroidism, a distal vacuolar myopathy, pancreatic exocrine and endocrine insufficiency, male hypogonadism, and idiopathic intracranial hypertension. Cystinosis is diagnosed biochemically by measuring the cystine content of leucocyte and molecularly by identifying pathogenic variants in CTNS. Prenatal diagnosis is available. Treatment consists of replacement of kidney tubular losses, symptomatic management of systemic complications, and specific therapy directed at the basic defect, i.e., lysosomal cystine accumulation. This involves the free thiol cysteamine, which can deplete approximately 95% of the lysosomal cystine content. Oral cysteamine therapy has extended the time to kidney failure by approximately 7 years (to a mean of 16 years) and mitigates or prevents late complications of the disease. In addition, cysteamine eyedrops can dissolve corneal cystine crystals within months. Nevertheless, the mean age at death for individuals born between 1985 and 1999 has been 29 years, and earlier diagnosis by newborn screening, treatment with more palatable cystine-depleting agents, and trials with gene therapy are critical current pursuits.

Background: Few studies are available on changes in maintenance immunosuppression after pediatric kidney transplantation (KT). This is a retrospective registry analysis of the long-term medication modifications in the Nordic countries.

Methods: All pediatric KT recipients transplanted between the years 2005 and 2016 were identified from the Scandiatransplant registry. Of the 482 patients, 345 met the inclusion criteria: age below 16 years at KT and at least 2 years post-transplant follow-up.

Results: A change in maintenance immunosuppression occurred in 160 patients (46.4%) at 2.0 (interquartile range 1.0-3.0) years median time from KT. The most common change (35.8%) was switching cyclosporine A (CsA) to tacrolimus (Tac). Initial CsA treatment was modified significantly more often compared to Tac (72.0% vs. 6.0%; p < 0.001). Modifications of mycophenolate mofetil (MMF) were observed more often in recipients aged < 2 (75.0%) and 2-5 (55.6%) years compared with 5-16 years (13.2%; p < 0.001); particularly, MMF discontinuation was common (< 2 years 45.8% and 2-5 years 38.9%). Otherwise, initial immunosuppression remained mainly unchanged. The main reasons for changing CsA to Tac were cosmetic side effects (26.2%), rejections (26.2%), and declining graft function (23.0%). In case of rejection or declining graft function, CsA-to-Tac conversion slowed the decrease in measured glomerular filtration rate. MMF modifications did not affect graft survival from 2 to 7.5 years post-transplant.

Conclusions: Maintenance immunosuppression is modified in almost half of pediatric KT recipients. Particularly, CsA conversion to Tac and young recipients' MMF modifications are common.

Background: Few randomized controlled trials are conducted in childhood nephrotic syndrome, and substantial global practice variation exists. Trials have not reported consistent outcomes, patient-reported outcomes, or justified minimal clinically important differences (MCID). Our aim was to establish consensus on core outcomes, assessment timepoints, MCIDs, and desirability of outcome ranking (DOOR) endpoints for future childhood steroid-sensitive nephrotic syndrome research.

Methods: We conducted a two-stage Delphi consensus survey of international healthcare providers and Canadian patients and caregivers with experience in childhood nephrotic syndrome. Respondents rated potential outcomes using Likert scales and assigned MCID values for relapse and remission endpoints. Following the surveys, we held workshops for healthcare providers and patients/caregivers in Toronto, Canada, with facilitated discussions. Qualitative data was analyzed thematically to explore perspectives on childhood nephrotic syndrome clinical trial outcomes and MCIDs.

Results: Eighty-one participants (45 providers, 36 patients/caregivers, 63% Canadian) responded to the surveys. Three disease outcomes (relapse rate, relapse-free survival, and relapse occurrence) met consensus criteria as core outcomes. Median MCID values were a 25% absolute difference between two treatments in relapse risk by 1-year (for relapse prevention) choices and 10% absolute difference in remission by 2 weeks (for relapse treatment). Consensus was achieved for five core patient-reported outcomes (pain, physical symptoms, physical function and mobility, life participation, and social function) and DOOR endpoints for nephrotic syndrome relapse and remission.

Conclusions: Consensus exists among surveyed participants on core disease and patient-reported outcomes for childhood nephrotic syndrome research. Findings can improve the quality and reporting of future trials in this population.

Background: Extra-renal complications are severe in Shiga toxin-producing E. coli hemolytic uremic syndrome (STEC-HUS), with pericardial effusion being rare and inadequately characterized. This study aimed to describe the clinical and biological data, management strategies, and risk factors associated with pericardial effusion in children with STEC-HUS.

Methods: This multicentric retrospective study included all consecutive children under 18 years who developed pericardial effusion during STEC-HUS in France between 2017 and 2022. Paired comparisons were made with control children presenting STEC-HUS in the same centres, before and after the index cases.

Results: A total of 15 cases were identified. The pericardial effusion group exhibited significantly more extra-renal manifestations compared to 30 control cases. Leukocyte counts were higher in the pericardial effusion group (22.2 G/L vs. 14.5 G/L, p = 0.002), as were hematocrit levels (30.1% vs. 24.2%, p = 0.02). Fourteen children received eculizumab, and 8 out of 15 required pericardial drainage. Two patients died from non-cardiac causes. Myopericarditis was identified in 5 cases, and 5 of the 14 patients had normal troponin levels during the initial phase.

Conclusions: Children with pericardial effusion during STEC-HUS exhibited more extra-renal manifestations and biological markers indicative of severe HUS at presentation. These findings suggest that patients with severe STEC-HUS and extra-renal manifestations requiring intensive care should be routinely screened for pericardial effusion.