Age- and sex-dependent clinical equations to estimate glomerular filtration rates in children and young adults with chronic kidney disease

Characteristics of patients with autosomal polycystic kidney disease reaching kidney failure by age 40

BACKGROUND

Autosomal dominant polycystic kidney disease (ADPKD) demonstrates broad genetic and phenotypic variability, with kidney failure (KF) occurring across a wide age spectrum. Despite several predictor tools, there remains a need to identify factors associated with rapid disease progression. This study describes the phenotypic characteristics of a multicentric cohort experiencing early-onset KF by age 40.

METHODS

This retrospective, multicenter cohort study analyzed longitudinal data of rapidly progressive ADPKD patients (n = 199). The prevalence of established risk factors was compared to nine existing ADPKD cohorts (ntotal = 6782) with KF after 40 years of age. We examined the longitudinal impact of early hypertension and urological events on the risk of developing KF.

RESULTS

The median age at ADPKD diagnosis was 22.3 years (IQR, 16.5-28.6) and median age of KF was 35.6 years (31.7-38.0). Hypertension was observed in 68.1% of cases, with early-onset hypertension being more common among those with accelerated progression towards KF. Urological events were present in 60.1% of cases, with a high burden of gross hematuria (30.4%). Existing ADPKD cohorts had a mean age of 45.5 years, with weighted prevalences of hypertension (71.1%), kidney stones (22.4%), hematuria (22.9%), and urinary tract infections (22.8%). Extrarenal manifestations were less prevalent compared to other ADPKD cohorts.

CONCLUSION

This study outlines a cohort of ADPKD patients with accelerated disease progression, reaching KF before age 40. Hypertension and urological events were highly prevalent at a young age, emphasizing the importance of early and regular blood pressure monitoring.

Age-specific associations between per- and polyfluoroalkyl substances exposure and metabolic syndrome: a cross-sectional study

BACKGROUND

The widespread presence of per-and polyfluoroalkyl substances (PFAS) has raised global health concerns. This study aims to determine the age-specific relationships of PFAS compounds with metabolic syndrome (MetS) and its components.

METHODS

We used data from the National Health and Nutrition Examination Survey (NHANES) in 2003-2018. Modified Poisson regression was employed to estimate associations between individual PFAS compounds and prevalence of MetS, as well as its components. Multiple linear regression analyses were performed to examine the associations between PFAS congeners and metabolic markers, including lipid and glucose homeostasis traits. Additionally, weighted quantile sum (WQS) regression and Bayesian kernel machine regression (BKMR) models were conducted to investigate the joint effects of PFAS mixtures on the prevalence of MetS and its components across different age groups.

RESULTS

A total of 5850 participants were included for analysis. In the Modified Poisson regression model, ln-transformed perfluorononanoic acid (PFNA) level was positively correlated with MetS prevalence in adolescents (prevalence ratio [PR] = 1.42; 95% CI: 1.01-1.99). Conversely, ln-transformed perfluorohexanesulfonic acid (PFHxS) and ln-transformed 2-(N-Methylperfluorooctane sulfonamido) acetic acid (MeFOSAA) were negatively associated with the risks of MetS in young adults (PR = 0.86, 95% CI: 0.76-0.98) and middle-aged adults (PR = 0.88, 95% CI: 0.79-0.98), respectively. Notably, individual PFAS exposure was positively associated with levels of total cholesterol, low-density lipoprotein, non-high-density lipoprotein, and high-density lipoprotein in young and middle-aged adults. However, overall effect analyses using WQS and BKMR showed no significant associations of PFAS mixture with MetS in any age group. Nonetheless, in middle-aged adults, PFAS mixture was adversely correlated with hypertriglyceridemia and positively linked to a greater risk of hypertension and increased high-density lipoprotein cholesterol levels.

CONCLUSIONS

Our study highlighted the complex relationships between PFAS exposure and the risks of MetS and its components across different age groups. Co-exposure to PFAS was particularly linked to dyslipidemia in young and middle-aged adults. Prospective studies are needed for better comprehension of the causative impact of PFAS on the risks of MetS.

Evaluation of Pediatric and Young Adult Cancer Survivors at Risk of Long-Term Kidney Complications

BACKGROUND

Nephrotoxic chemotherapy, nephrectomy, abdominal radiotherapy exposure, and the presence of kidney or pelvic tumors are risk factors associated with long-term kidney complications. This study aimed to determine the prevalence of long-term kidney complications in patients who survived pediatric and young adult cancer and were exposed to those risk factors in the current anticancer treatment era.

METHODS

This retrospective study included patients who survived pediatric and young adult cancer and received nephrotoxic chemotherapy, nephrectomy, abdominal radiotherapy, and/or had kidney or pelvic tumors. Patients were under follow-up at Nationwide Children's Hospital pediatric cancer survivors' clinic between January 1, 2016 and December 31, 2021.

RESULTS

A total of 109 patients met inclusion criteria. Long-term kidney complications included low glomerular filtration rate (GFR) (11.9%), hyperfiltration (22.9%), and hypertension (49.5%). Risk factors associated with low GFR included surviving childhood solid tumors, nephrectomy, carboplatin, and ifosfamide treatments. Urinalysis was available in 64 patients (58.7%), and of those, five had proteinuria-associated long-term kidney complications.

CONCLUSIONS

Long-term kidney complications are prevalent in patients who survived pediatric and young adult solid tumors. Current guidelines do not recommend evaluation of urinalysis or albuminuria in patients at risk of long-term kidney complications, which can significantly impact their treatment.

Long-term kidney outcomes in survivors of Wilms tumor: a single-center retrospective cohort study

BACKGROUND

Several studies have investigated long-term kidney outcomes in survivors of Wilms tumor (WT). However, many have small sample sizes, and there is a wide variation in reported outcomes. The aim of this study is to investigate the long-term kidney outcomes in survivors of WT (S-WT), including those patients considered to be at high risk for poor kidney outcomes, and using updated estimated glomerular filtration rate (eGFR) equations.

METHODS

This was a retrospective chart review of 64 patients treated for WT at a single pediatric center. Patients were off treatment for 5 years or more at the time of analysis and were evaluated for decreased kidney function, hypertension, proteinuria, and compensatory hypertrophy of the contralateral kidney.

RESULTS

At a median follow-up time of 11.3 years off treatment (range 5-22.6) and average age of 16.7 years (range 6.5-30), 35 patients had a decreased eGFR (< 90 mL/min/1.73 m2), and 2 patients had progressed to chronic kidney disease stage 5. Compensatory hypertrophy was observed in 67% of cases. 41% of patients had elevated clinic blood pressures, with 2 patients on an anti-hypertensive medication. Three of 9 patients had evidence of hypertension on ambulatory blood pressure monitoring. Eight of 37 patients (22%) had proteinuria.

CONCLUSIONS

Kidney dysfunction is common in S-WT at a young age. This population should be carefully monitored for the development of decreased eGFR, hypertension, and proteinuria as part of their routine survivorship care. This is particularly true for modifiable risk factors of chronic kidney disease progression, such as hypertension and proteinuria.

Vanadium exposure and kidney markers in a pediatric population: a cross-sectional study

BACKGROUND

Anthropogenic vanadium (V) emissions and exposure in the general population have recently increased. Experimental studies have shown that V is a nephrotoxic agent, but little is known about its effects on human kidney health. This work evaluated the association between urinary V concentrations with early kidney damage biomarkers and function in a pediatric population without any disease diagnosed.

METHODS

A cross-sectional study was carried out and included 914 healthy subjects and determined urinary V concentrations, glomerular filtration rate (eGFR), albumin-creatinine ratio (ACR), and the presence of kidney injury molecule 1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL) in urine. We evaluated the V effect using linear and logistic regression models adjusted by confounders.

RESULTS

Subjects found in the second and third tertiles of V showed an increase in urinary log-NGAL levels (βT2 vs. T1 = 0.39; 95% CI 0.14, 0.64, and βT3 vs. T1 = 1.04; 95% CI 0.75, 1.34) and log-KIM-1(βT2 vs. T1 = 0.25; 95% CI 0.04, 0.45 and βT3 vs. T1 = 0.39; 95% CI 0.15, 0.63); in addition, subjects in the third tertile had a positive and significant association with ACR (ORT3 vs. T1 = 1.96; 95% CI 1.29, 2.97) and increased in eGFR (βT3 vs. T1 = 3.98, 95% CI 0.39, 7.58), compared with subjects in the first tertile.

CONCLUSIONS

Our study reports the effect of V on kidney markers in a healthy pediatric population. It could be related to tubulointerstitial lesions and function abnormalities.

Left atrial mechanics in youth with chronic kidney disease and similarly aged healthy controls

BACKGROUND

In adults with chronic kidney disease (CKD), abnormal left atrial reservoir strain (LASr) is an early, yet clinically significant, indicator of myocardial dysfunction. However, left atrial mechanics are understudied in youth with CKD. The objective of this study was to assess left atrial strain function in youth with CKD and similarly aged, healthy controls.

METHODS

We performed a single-center, retrospective, observational study of persons aged 12-21 years with stage 3-4 CKD and healthy controls. Exclusion criteria included a history of a kidney or other solid organ transplant, congenital heart disease, and/or dialysis requirement < 3 months prior. We measured LAS (LASr, conduit, and contractile), E/e', E/A, left ventricular mass index (LVMI), and ejection fraction. Pearson correlations were performed between echocardiographic measures.

RESULTS

This study included 37 patients with CKD and 19 controls. Mean age was similar between groups, and male sex was over-represented in both groups (CKD 62%; healthy 63%). Mean ± standard deviation (SD) eGFR in the CKD group was 32 ± 14 mL/min/1.73 m2. Mean absolute LASr was lower in those with CKD (43.0 ± 8.5%) compared to healthy controls (47.4 ± 6.1%) p = 0.050. Patients with CKD had significantly higher LVMI and lower E/A and E' compared to controls. There was poor correlation between LASr with E/A, E/e', and LVMI.

CONCLUSIONS

As observed in adults with CKD, LASr trended lower in youth with CKD compared to healthy controls. Moreover, LASr poorly correlated with traditional measures of diastolic dysfunction such as E/e' and E/A.

Prophylactic anticoagulation in patients with nephrotic syndrome in the Cure Glomerulonephropathy (CureGN) cohort

Background

Adult and paediatric patients with nephrotic syndrome (NS) due to different glomerular diseases are at a higher risk of thromboembolic events than the general population, but the use of prophylactic anticoagulation (PAC) among them has not been well described. Although the 2021 Kidney Disease: Improving Global Outcomes (KDIGO) guidelines offer an algorithm to guide the management of PAC, the degree of implementation in practice is unknown.

Methods

We evaluated thromboprophylaxis management in patients with NS secondary to membranous nephropathy, focal segmental glomerulosclerosis, minimal change disease and C1q nephropathy enrolled in the Cure Glomerulonephropathy (CureGN) cohort study (diagnosed 2010-2023) and assessed the concordance or discordance with the 2021 KDIGO guidelines practice points in adults. We also analysed thrombotic and bleeding events.

Results

Among 374 adult and 263 paediatric NS episodes, PAC was prescribed in 21 (6%) and 11 (4%) episodes, respectively. In adults, PAC prescription was associated with a history of prior thrombosis, lower serum albumin and higher proteinuria, with coumarins and direct oral anticoagulants (DOACs) being equally the most prescribed agents. In adults, anticoagulation management was concordant with guidelines in 180 (48%) episodes, discordant in 59 (16%) and indeterminate in 135 (36%). Most (92%) guideline-discordant episodes were cases with a high thrombotic risk and low bleeding risk where PAC was not prescribed. In children, PAC prescription was associated with lower albuminaemia and worse kidney function, with heparins being the only agent used. Thrombotic events occurred during 5 (1.3%) and 4 (1.5%) of all adult and paediatric NS episodes, respectively.

Conclusions

PAC was used more conservatively than guidelines suggest and was mainly driven by hypoalbuminaemia severity in both adults and children. Although not included in the guidelines practice points, DOACs were used as often as coumarins in adults.

Urinary peptide signature distinguishes autosomal recessive polycystic kidney disease from other causes of chronic kidney disease

Background

The diagnosis of autosomal recessive polycystic kidney disease (ARPKD) can be hampered by its pronounced phenotypic variability and ARPKD-mimicking phenocopies. Here, for the first time we specifically studied the urinary peptidome of patients with ARPKD with the aim of distinguishing ARPKD from other causes of chronic kidney disease (CKD).

Methods

Fifty-eight urine samples from patients with ARPKD, 662 urine samples from paediatric patients with CKD with various other CKD aetiologies and 45 samples from healthy children were included. The urinary peptidome was analysed by capillary electrophoresis/mass spectrometry.

Results

A 77-peptide signature specific for ARPKD was identified. Application of this signature in a matched random validation set of 19 samples of patients with ARPKD, 23 samples from patients with other CKD and 21 samples from healthy individuals led to a sensitivity of 84.2% [95% confidence interval (CI) 60.4-96.6], a specificity of 100% (95% CI 92.0-100%) and an area under the receiver operating characteristics curve (AUC) of 0.994 (95% CI 0.93-1.00). The 77-peptide signature displayed a specificity of 76.1% (95% CI 72.4-79.5) and an AUC of 0.88 (95% CI 0.85-0.90) in 591 samples from non-matched children with various CKD aetiologies. The signature was primarily (83%) composed of collagen fragments indicating structural damage. Of the remaining peptides, five originated from proteins known to bind to calcium potentially linking the current work to defaults in calcium signalling in polycystic disease.

Conclusions

We determined a urinary peptide signature that identifies paediatric patients with ARPKD with high precision among a population of children with CKD. Knowledge of the identity of the underlying peptides offers a novel starting point for discussion of possible pathophysiological processes involved in ARPKD.

Prolonged remission after cyclophosphamide or tacrolimus treatment in childhood nephrotic syndrome: a cohort study

BACKGROUND

Steroid-sparing immunosuppression is used in 50% of children with nephrotic syndrome, to prevent relapses and steroid-related toxicity. However, rates and predictors of prolonged remission after cyclophosphamide and tacrolimus are uncertain.

METHODS

Retrospective analysis of children (1-18 years) enrolled in a longitudinal cohort. We included children diagnosed with steroid-sensitive nephrotic syndrome between 1996-2019 from Toronto, Canada. The exposure was cyclophosphamide or tacrolimus initiation. The primary outcome was prolonged remission (no further relapse or steroid-sparing immunosuppression). We evaluated predictors of prolonged remission and calcineurin inhibitor nephrotoxicity by logistic regression.

RESULTS

Of 578 children with steroid-sensitive nephrotic syndrome, 252 received cyclophosphamide and 120 received tacrolimus. Over median 5.4-year (IQR 2.4-9.1) follow-up, prolonged remission occurred in 72 (28.6%) after cyclophosphamide and 17 (14.2%) after tacrolimus. Relapse frequency decreased after initiation of either medication. Lower prior relapse rate, more recent treatment era, and female sex were predictive of prolonged remission after cyclophosphamide treatment. Use of tacrolimus as the first steroid-sparing medication was the only factor predictive of calcineurin inhibitor nephrotoxicity.

CONCLUSIONS

Less than one-third of children achieve prolonged remission after initiating cyclophosphamide or tacrolimus, although both reduce short-term relapse rates. Few factors predict prolonged remission after cyclophosphamide or tacrolimus use, or calcineurin inhibitor nephrotoxicity.

Investigation of a targeted panel of gut microbiome-derived toxins in children with chronic kidney disease

BACKGROUND

The gut-kidney axis is implicated in chronic kidney disease (CKD) morbidity. We describe how a panel of gut microbiome-derived toxins relates to kidney function and neurocognitive outcomes in children with CKD, consisting of indoleacetate, 3-indoxylsulfate, p-cresol glucuronide, p-cresol sulfate, and phenylacetylglutamine.

METHODS

The Chronic Kidney Disease in Children (CKiD) cohort is a North American multicenter prospective cohort that enrolled children aged 6 months to 16 years with estimated glomerular filtration rate (eGFR) 30-89 ml/min/1.73 m2. Data from the 2-year study visit were used for this analysis. Toxin quantification (Metabolon Inc., Durham, NC) was performed with ultra-high performance liquid chromatography/tandem mass spectrometry. Executive function and echocardiograms were assessed. Regression analysis examined the association of toxin levels with eGFR, CKD etiology, and neurocognitive and cardiac assessments (adjusted for age, sex, and urine protein:creatinine [UPCR]).

RESULTS

There were 150 CKiD participants included in this study. All toxins levels were significantly inversely correlated with eGFR (Spearman's rho - 0.45 to - 0.69). Children with non-glomerular CKD had significantly higher levels of 3-indoxylsulfate, phenylacetylglutamine, and p-cresol glucuronide. The toxin levels did not associate with neurocognitive outcomes. P-cresol glucuronide and phenylacetylglutamine negatively associated with left ventricular mass index z score, but did not associate with left ventricular hypertrophy.

CONCLUSIONS

Children with CKD have high levels of circulating gut microbiome-derived toxins. The levels of these toxins are strongly correlated with eGFR. There appear to be differences in toxin level based on glomerular versus non-glomerular etiology, even when accounting for the differences in eGFR between these two subgroups. In this sample, we did not detect any associations between these toxin levels and neurocognitive or cardiac outcomes.

Noninvasive Diagnostic Strategies for Membranous Nephropathy in the Nephrotic Syndrome Study Network

Key Points

Background

Clinical practice guidelines recommend that a kidney biopsy is no longer required to confirm a diagnosis of membranous nephropathy (MN) in patients with nephrotic syndrome and a positive test for antiphospholipase A2 receptor antibodies (PLA2R-Ab). However, the optimal diagnostic strategy for using the PLA2R-Ab ELISA, PLA2R-Ab indirect immunofluorescence (IIF) test, and genetic risk score (GRS) for diagnosing MN, including the tests' optimal thresholds for positivity among incident patients with proteinuria, is still unknown.

Methods

We used serum samples at or before the first clinically indicated kidney biopsy from participants in the Nephrotic Syndrome Study Network to analyze test performance characteristics using different combinations and cutoffs of the PLA2R-Ab ELISA, IIF, and GRS for diagnosing MN. Secondary analyses included serum samples within 6 months after biopsy but before any immunosuppression use.

Results

There were 325 study participants with serum samples available on or before the day of kidney biopsy and an additional 143 study participants with samples within 6 months after biopsy but before any immunosuppression use. Of these participants, 26% (n=85) had biopsy-confirmed MN. The combination of ELISA ≥2 RU/ml and positive IIF was the optimal approach, with sensitivity of 0.60, specificity of 1.00, negative predictive value of 0.92, and positive predictive value of 1.00. Using IIF to confirm only borderline ELISA titers between 2 and 20 RU/ml resulted in similar sensitivity but specificity of >0.99. In our multiethnic study sample, we did not find improved diagnostic performance with the addition of GRSs.

Conclusions

In the Nephrotic Syndrome Study Network cohort, combined PLA2R-Ab testing with ELISA and IIF provided optimal test characteristics in making a noninvasive diagnosis of MN before or soon after kidney biopsy, including in patients with subnephrotic proteinuria. Further studies in multiethnic populations are needed to assess whether genetic data can augment this approach.

Is body composition important in the context of renal function in pediatric neurogenic bladder?

BACKGROUND

Neurogenic bladder due to myelomeningocele (MMC) is a significant risk factor for chronic kidney disease in children. Cystatin C (CysC) is a more accurate GFR marker than creatinine as it is unaffected by muscle mass but may be influenced by fat mass and BMI. This study evaluates: (1) GFR measurement accuracy using CysC and creatinine in MMC-related neurogenic bladder, (2) the relationship between body composition via bioelectrical impedance analysis (BIA) and renal parameters, and (3) the use of BIA for non-invasive GFR and body composition assessment.

METHODS

Forty children (median age 9.96 years) underwent serum creatinine, CysC testing, and BIA measurements. We assessed age, sex, spinal lesion level, anthropometric measurements, BMI, and activity using Hoffer's scale. GFR was calculated using five creatinine-based formulas, three CysC-based, and three combining CysC and creatinine, including BIA GFR as an alternative approach.

RESULTS

Creatinine-based GFR estimates were significantly higher than CysC-based GFR. Although only 30% of MMC patients met the traditional BMI criteria for overweight/obesity, 62.5% were obese based on BIA-measured body fat percentage. Significant differences were found in CysC and CysC-based GFR equations within BMI and fat mass groups. Positive correlations were observed between CysC and body weight, BMI percentiles, body fat mass and fat-to-muscle ratio. Muscle mass positively correlated with creatinine.

CONCLUSIONS

BIA-determined fat mass percentage is a more sensitive obesity indicator than BMI in MMC patients. CysC levels and CysC-based GFR equations are influenced by body fat mass, requiring consideration of adiposity to avoid misestimating renal impairment.

A comparison of neural networks and regression-based approaches for estimating kidney function in pediatric chronic kidney disease: Practical predictive epidemiology for clinical management of a progressive disease

PURPOSE

Clinical management of pediatric chronic kidney disease requires estimation of glomerular filtration rate (eGFR). Currently, eGFR is determined by two endogenous markers measured in blood: serum creatine (SCr) and cystatin C (CysC). Machine learning methods show promise to potentially improve eGFR, but it is unclear if they can outperform regression-based approaches under clinical constraining requiring real time measurement and only two predictors. We constructed a neural network for eGFR (NNeGFR) and compared it to the clinical standard Under 25 (U25eGFR) equations using the same data for training and validation.

METHODS

The U25eGFR data comprised 1683 training and 843 validation observations that included iohexol measured GFR (mGFR), SCr and CysC. Sex-stratified feed forward NNs included the same predictors as U25eGFR (i.e., age, height/SCr, CysC) with additional nonlinear transformations. Performance was evaluated by bias (for calibration), proportions within 10 % and 30 % of mGFR (P10 and P30, for accuracy), root mean square error (RMSE, for precision) and R2 (for discrimination).

RESULTS

NNeGFR performed comparably to the U25eGFR equations on all metrics. Biases were minimal, slightly favoring U25eGFR. NNeGFR and U25eGFR had similar P10 (>37 %), P30 (>86 %) and RMSE.

CONCLUSIONS

NNeGFR performed as well as established equations to estimate GFR. Without additional biomarkers related to kidney function, which are not currently clinically available in real time, NN methods are unlikely to substantially outperform regression derived GFR estimating equations. Implications for translation of these advanced epidemiologic methods to clinical practice are discussed.

Seraph 100 Microbind Affinity Blood Filter for Persistent Pediatric BK Virus Nephropathy

BACKGROUND

Resolution of BK viremia is almost universally required before kidney transplant. Unfortunately, proven anti-BK viral therapies are limited. The Seraph 100 mimics the action of the natural glycocalyx, which binds pathogens via heparin sulfate proteoglycans. In this case report, we describe the use of this filter to facilitate the clearance of BK viremia.

METHODS

Our patient was a 14-year-old cardiac transplant recipient secondary to familial dilated cardiomyopathy. She developed BK nephropathy resulting in end stage kidney disease (ESKD). After failed medical management and immunoreduction over 4 years, the Seraph 100 Microbind Affinity Blood Filter was utilized extracorporeally in line with continuous renal replacement therapy (CRRT) for 48 h to eliminate detectable BK viral replication.

RESULTS

The patient's BK titers initially increased negligibly but cleared within 2 months of Seraph 100 treatment, and she successfully underwent kidney transplantation without recurrence of BK viremia. There were no adverse events other than one episode of emesis at the initiation of CRRT.

CONCLUSION

Our case provides proof of concept and feasibility for studying the Seraph 100 as a potential therapeutic option for the clearance of BK viral titers, especially in ESKD patients who already have dialysis access.

Variability in Meropenem Distribution and Clearance in Children with Sepsis: Population-Based Pharmacokinetics with Assessment of Renal Biomarkers

BACKGROUND AND OBJECTIVE

Meropenem dosing to achieve therapeutic exposure in critically ill children with sepsis is challenging due to a spectrum of renal function, from augmented renal clearance (ARC) to acute kidney injury (AKI). The objective of this study was to define meropenem plasma concentrations and pharmacodynamic exposure metrics in children with septic shock during the first 3 days of PICU hospitalization.

METHODS

We prospectively evaluated meropenem clearance (CLMERO) and volume of distribution (V1-MERO), innovatively assessing renal biomarkers (serum creatinine [SCr], serum cystatin C [SCys], and neutrophil gelatinase-associated lipocalin [SNgal]), in infants aged ≥ 4 weeks and children on intravenous (IV) meropenem 20 mg/kg every 8 h from 2019 to 2023. Cases with sepsis were matched to controls without sepsis.

RESULTS

Analysis included 27 participants (19 cases and 8 controls) with 309 meropenem serum concentrations. Median age was 11.8 (range 0.6-19.6) years, weight 36.3 (7.2-98.0) kg, SCr 0.33 (0.09-2.57) mg/dL, SCys 451.1 (178.3-1824.1) ng/mL, and SNgal 180.7 (23.2-1403.0) ng/mL. A 2-compartment, population pharmacokinetic (PK) model via NONMEM best described data, with weight on VMERO and allometric scaling on CLMERO. Using the final model with SCys in V1-MERO and estimated glomerular filtration rate (eGFR)-MS in CLMERO, the median V1-MERO was 0.23 (range 0.07-0.57) L/kg and CLMERO 0.15 (0.05-0.49) L/h/kg, with eGFR-MS 139 (23-365) mL/min/1.73 m2 from AKI to ARC. Meropenem clearance, V1-MERO and eGFR-MS were significantly decreased in cases versus controls, with higher variability of eGFR-MS in cases.

CONCLUSION

Wide variation in meropenem concentrations in children with sepsis as compared to those without sepsis prompt close monitoring of GFR and drug concentrations in this population.

Glomerular filtration rate and sexual dimorphism: lessons from animal and human studies

PURPOSE OF REVIEW

Integrating sex-based analyses is becoming a key point in the new recommendations, particularly in nephrology.

RECENT FINDINGS

Whereas single nephron glomerular filtration rate (GFR) is not different between men and women, male sex is associated, after multiple adjustments, with a higher number of nephrons. However, after indexation to body surface area, measured GFR (mGFR) in healthy potential kidney donors is not different between men and women between 20 and 50 years of age. After 50 years, mGFR decline seems faster in women than in men, which is concordant with the protective role of estrogens on renal function, as demonstrated in animal and some human studies. Conversely, testosterone has a detrimental effect on renal function. Of note, although testosterone has been shown to increase the kidney volume of the remnant kidney after a unilateral nephrectomy in animal models, this may generate deleterious hyperfiltration in the longer term.

SUMMARY

Taken together, these data highlight the impact of sex on GFR, notably through sexual hormones whose receptors are expressed in glomerular cells.

Comparison of GFR estimation equations using creatinine, cystatin C, and their combination in pediatric hematology-oncology: no single equation is superior across subgroups

BACKGROUND

Accurate assessment of renal function is essential in treating pediatric patients dosed with nephrotoxic chemotherapy. The validity of the bedside Schwartz, 5-covariate St. Jude (5SJ), CKiD-CysC-U25, combined Cr-CysC-based CysPed, and the serum creatinine-BUN-cystatin C-based CKiD (CKiD Cr-CysC) equations were evaluated in pediatric hematology and oncology patients.

METHODS

A retrospective analysis was conducted comparing estimated glomerular filtration rate (eGFR) to measured GFR (mGFR) obtained from technetium- 99 m diethylenetriaminepentaacetic acid (99 mTc-DTPA) clearance between January 2016 and May 2022. The influence of corticosteroid use and inflammation in our patient population was evaluated for effect on serum cystatin C (CysC) concentrations and mGFR.

RESULTS

All equations agreed within 2 SD of the mean difference with mGFR, but the 5SJ equation had the smallest bias followed closely by the CysPed equation. Overall accuracy (P30) was assessed, and the 5SJ, CKiD Cr-CysC, CysPed, and CKiD-Cys-U25 exhibited comparable performance. In our patient population, we did not observe an effect of corticosteroids (cumulative dosage of > 0.5 mg/kg within the past 14 days) or the presence of inflammation (CRP > 1.2 mg/L) on cystatin C concentrations or mGFR.

CONCLUSIONS

In our pediatric hematology and oncology patient population, no one estimating equation demonstrated superior accuracy and bias overall and in all subgroups. Neither corticosteroid use nor elevated CRP influenced serum CysC concentrations or eGFR.

Incontinent Enterovesicostomy in the Pediatric Population: A Feasible Option for Surgical Management of Neurogenic Bladder

OBJECTIVE

To report outcomes of a series of pediatric patients undergoing incontinent enterovesicostomy. Incontinent enterovesicostomy is a viable procedure for bladder reconstruction in pediatric patients with neurogenic bladder, but clinical outcomes data in this age group are scarce.

MATERIALS AND METHODS

A retrospective chart review was conducted on pediatric patients (<18 years old) who underwent incontinent enterovesicostomy at a single institution between 2011 and 2024. Data were collected from electronic medical records and analyzed using descriptive statistics.

RESULTS

A total of 26 pediatric patients (14 female, 12 male) with neurogenic bladder underwent incontinent enterovesicostomy at a median age of 12.4years (IQR: 6.4-14.0years). The median follow-up duration was 18.99months (IQR: 11.2-44.7months), and most patients (76.9%) had a primary diagnosis of myelomeningocele. Indications for surgery included recurrent urinary infections, urethral incontinence, and bladder hostility. The median operative time was 241.5 minutes (IQR: 192-273 minutes), and the median hospital stay was 5days. Within 30days postsurgery, 76.9% of patients experienced no complications. Renal function remained stable in all patients, and hydronephrosis status worsened in only 1 patient.

CONCLUSION

Enterovesicostomy is a safe, feasible, and effective surgical option for managing neurogenic bladder in pediatric patients. It reliably treats bladder hostility and protects upper urinary tract function with a low complication rate. Future research should focus on prospective, multicenter studies comparing long-term outcomes of incontinent enterovesicostomy with augmentation cystoplasty.

The Importance of Hepatic Surveillance After Single-Ventricle Palliation: An Interventional Study Validating Liver Elastography

Predictors of Fontan-associated liver disease (FALD) are not well defined. We hypothesized that magnetic resonance elastography liver stiffness measurement (LSM) would correlate with cardiac MRI findings, and hemodynamic, clinical, radiographic, and laboratory measures of FALD and Fontan failure. Patients undergoing pre- and post- Fontan assessment with same-day MRI and cardiac catheterization were enrolled. Data was collected retrospectively. 22 Fontan (mean age 12.1 ± 7.5 years) and 17 Glenn patients (mean age 4.0 ± 0.9 years) were retrospectively enrolled. LSM was higher in Fontan vs Glenn patients (3.8 ± 0.6 kPa vs 2.2 ± 0.4 kPa; p < 0.0001), as were all fibrosis scores (FIB- 4 = 0.4 ± 0.2 vs 0.1 ± 0.1, respectively, p = 0.002). LSM positively correlated with hepatic wedge pressure (r = 0.75; p < 0.0001), and all fibrosis scores (FIB- 4; r = 0.55; p = 0.001). There was negative correlation with LSM and ejection fraction (r = - 0.64; p < 0.0001). Comparing those with Fontan failure (n = 8) and those without (n = 14), only ejection fraction was statically significant (41 ± 12% vs 51 ± 4%, respectively; p = 0.012). Of the patients in Fontan failure, there was no difference in LSM between those with FALD (n = 3), and those without (n = 5), (3.7 ± 0.3 kPa vs 3.8 ± 0.6 kPa; p = 0.72). On multivariable regression analysis, LSM and GGT were independently associated with elevated hepatic venous pressure (p = 0.004 and p = 0.016, respectively). There was no correlation with LSM and Fontan duration (r = 0.15; p = 0.517). Liver stiffness rises significantly after Fontan palliation and positively correlates with hemodynamic and clinical markers of hepatic congestion and fibrosis, however its ability to predict Fontan failure and FALD remains uncertain.

Donor-derived cell-free DNA testing in pediatric kidney transplant recipients: indications and clinical utility

BACKGROUND

We describe our single-center experience in performing donor-derived cell-free DNA (dd-cfDNA) testing for a clinical indication in pediatric kidney transplant recipients.

METHODS

Dd-cfDNA was done for increase in creatinine, appearance of de novo anti-HLA antibodies (dnHLAab) and for a clinical indication. We compared clinical characteristics of patients with dd-cfDNA > 1 with those with dd-cfDNA ≤ 1 and also compared dd-cfDNA in patients with no biopsy proven rejection (BPAR) or dnHLAab with those with BPAR, and those with dnHLAab and no BPAR.

RESULTS

Chart review was performed in 106 patients with a mean age of 11.0 ± 5.5 years. When compared with 62 patients with dd-cfDNA ≤ 1, 59.0% (26/44) of patients with dd-cfDNA > 1 had BPAR (OR 13.5: 95%CI 4.6,38; p < 0.0001), and 88.1% (37/44) had dnHLAab (OR 60.3 95%CI 17.2,192.2; p < 0.0001). Patients with DQ and DR dnHLAab (OR 115.2: 95%CI 24.8, 509.5; p < 0.0001) and those with donor-specific antibodies (DSAs) (OR 50.8: 95%CI 13.0, 168.7; p < 0.0001) were likely to have dd-cfDNA > 1. A repeated measures linear mixed effect model revealed a significant difference in dd-cfDNA between those with no antibodies or BPAR (p < 0.0001) and patients with BPAR and dnHLAab, with or without DSA. At the end of the follow-up period, eGFR was 72 mL/min/1.73 m2 in those without BPAR or dnHLAab and was significantly different from those with BPAR (eGFR 51 mL/min/1.73 m2 (p < 0.0001).

CONCLUSIONS

Elevated dd-cfDNA is strongly associated with BPAR, class II dnHLAab and DSAs. Conversely, low values are observed in immunoquiescent states. Dd-cfDNA can be a useful tool for non-invasive clinical decision-making.

Kidney Transplantation in Congenital Abnormalities of Kidney and Urinary Tract (CAKUT)

Congenital anomalies of the kidney and urinary tract (CAKUT) are a common cause of chronic kidney disease in children. Most patients will reach end-stage renal function and dialysis or transplantation in childhood or early adulthood. Patients with CAKUT deserve a careful evaluation before a kidney transplant; detailed imaging and functional studies are necessary, particularly in the presence of lower urinary tract abnormalities, and surgical procedures are advisable in selected cases. A higher incidence of complications has been reported after a kidney transplant in CAKUT, mainly urinary tract infections. However, in the long term, the prognosis seems to be comparable to other kidney diseases. A large number of reports are available in the literature on medical and surgical management of patients with CAKUT before, during, and after a kidney transplant; almost all recommendations of surgical procedures before a kidney transplantation are based on retrospective not controlled studies or personal opinions; prospective controlled studies are needed. In this narrative, nonsystematic review, we report the results of recently published selected studies and underline questions that should be addressed in future guidelines.

New Index Demonstrates Association between Social Vulnerability, Environmental Burden, and Kidney Failure Risk among Individuals with Glomerular Disease

Key Points

More tools are needed to explore upstream drivers of racial and ethnic disparities in kidney disease outcomes. The Centers for Disease Control and Prevention Environmental Justice Index is a new tool which characterizes cumulative social and environmental burden at the census tract level. This study is the first application of the Environmental Justice Index to understanding glomerular disease outcomes.

Background

The Centers for Disease Control and Prevention Environmental Justice Index Social-Environmental Ranking (EJI-SER) combines a Social Vulnerability Module with an Environmental Burden Module to characterize cumulative environmental and social burden at the census tract level. This analysis evaluates the association between EJI-SER and kidney outcomes in patients with glomerular disease (GD).

Methods

Cure Glomerulopathy is an observational cohort study of adults and children with biopsy-proven GD. EJI-SER is a percentile ranking by census tract, with a higher score indicating a more severe burden. Associations between EJI-SER and its components with kidney failure (initiation of KRT, transplant, or two eGFRs <15 ml/min per 1.73 m2) and longitudinal eGFR were tested using multivariable Cox regression and linear mixed models, respectively, adjusted for demographics, histologic diagnosis, eGFR and urine protein to creatinine ratio at enrollment, and time from biopsy to enrollment.

Results

Among 1149 participants with census tract data, the median (interquartile range [IQR]) follow-up was 5.4 (3.0–7.0) years, the median (IQR) age at biopsy was 24 (10–48), and self-identified racial distribution was 5% Asian, 18% Black, and 70% White. Median (IQR) EJI-SER was 0.49 (0.26–0.75). EJI-SER scores in the lowest two quartiles were associated with a lower hazard of kidney failure compared with the highest quartile (adjusted hazard ratio [95% confidence interval], 0.62 [0.36 to 1.08] and 0.43 [0.25 to 0.76] for EJI-SER 0%–25% and >25%–50% versus >75%, respectively) and higher eGFR at enrolllment (adjusted mean 90.1 versus 87.1 ml/min per 1.73 m2 for 0%–25% versus >75%, P = 0.08).

Conclusions

As captured by EJI-SER, higher environmental and social burdens are associated with lower eGFR and a higher risk of kidney failure in the Cure Glomerulopathy cohort. This first use of the EJI-SER in GD demonstrates the need for additional investigation into social drivers of disparities in GD and policies and resources that address these structural inequities.

The Incidence and Outcomes of Acute Kidney Disease in Critically Ill Children

Key Points

Major adverse kidney events are common in children who develop acute kidney disease in the intensive care unit. Acute kidney disease criteria identify critically ill children at risk for major adverse kidney event who do not meet AKI or CKD criteria.

Background

Acute kidney disease (AKD) includes abnormalities of kidney function present for <90 days. AKI is defined as a subset of AKD with onset within 7 days. There are scant data on the rates of AKD in children and its association with outcomes. Our primary objective was to examine the rates of AKD with and without AKI and compare major adverse events in children in the pediatric intensive care unit (PICU).

Methods

This is a retrospective cohort study of patients aged 18 years or younger who were admitted to a quaternary care PICU between 2009 and 2016 using the high-density pediatric database. All patients included in the primary analysis had a known baseline serum creatinine. Patients who had a baseline eGFR <60 ml/min per 1.73 m2 or a history of dialysis dependence or kidney transplant were excluded. AKI and AKD were defined by Kidney Disease Improving Global Outcomes definitions. Major adverse kidney events at 90 days (MAKE-90) was defined as a composite outcome of death, dialysis, or persistent kidney dysfunction 90 days after PICU admission.

Results

Among 5922 children included in this study, 1199 (20.2%) had AKD, of which 1092 (91%) had AKD with AKI and 107 (8.9%) had AKD without AKI. MAKE-90 occurred in 26% (308/1199) of those with AKD compared with 3.6% (172/4723) without (P ≤ 0.001). MAKE-90 occurred in 26% (279/1092) of AKD with AKI and 27% (29/107) of AKD without AKI. After adjusting for age, sex, and illness severity, compared with patients who had no AKD, patients with AKD with AKI (adjusted odds ratio, 14.39; 95% confidence interval, 11.06 to 18.72), and patients with AKD without AKI (adjusted odds ratio, 7.83; 95% confidence interval, 4.54 to 13.51) had a greater odds of MAKE-90.

Conclusions

More than a quarter of pediatric critically ill patients with AKD develop MAKE-90. Even in the absence of AKI, AKD is an independent risk factor for MAKE-90.

Protocol and rationale for a randomized controlled SGLT2 inhibitor trial in paediatric and young adult populations with chronic kidney disease: DOUBLE PRO-TECT Alport

BACKGROUND

Clinical trials have demonstrated positive cardiovascular and kidney outcomes of sodium-glucose co-transporter 2 (SGLT2) inhibitors in adult patients with diabetic and other chronic kidney diseases (CKDs). Whether benefits extend to children, teenagers and young adults with early-stage CKD is unknown. For this reason, the DOUBLE PRO-TECT Alport trial (NCT05944016) will study the progression of albuminuria in young patients with Alport syndrome (AS), the most common hereditary CKD, to assess the safety and efficacy of the SGLT2 inhibitor dapagliflozin. Patients living with AS and chronically elevated albuminuria have a high risk of kidney failure before the age of 50 years.

METHODS

DOUBLE PRO-TECT Alport is a multicentre, randomized, double-blind, placebo-controlled trial. Participants (ages 10-39 years) must have a diagnosis of AS by genetic testing or kidney biopsy, be on a stable (>3 months) maximum tolerated dose of a renin-angiotensin system inhibitor and have a urinary albumin:creatinine ratio (UACR) of >300 mg/g (paediatric) or >500 mg/g (adult).Eligible participants will be randomly assigned at a 2:1 ratio to 48 weeks of treatment with dapaglifozin 10 mg/day or matched placebo. Most participants are expected to be children with a normal estimated glomerular filtration rate (eGFR). In addition to safety, the primary (change in UACR from baseline to week 48) and key secondary (eGFR change from baseline to week 52) efficacy outcomes will be analysed with a mixed model repeated measures approach. Efficacy analyses will be performed primarily in the full analysis set according to the intention-to-treat principle. A sensitivity analysis will be performed using reference-based multiple imputation.

CONCLUSION

DOUBLE PRO-TECT Alport will assess whether SGLT2 inhibitors can safely reduce the UACR change from baseline as a marker for progression of CKD in young patients living with AS.

Trends in Timing of Preemptive Kidney Transplantation and Association with Allograft and Survival Outcomes in Children

Key Points

Preemptive kidney transplant is occurring at higher levels of eGFR in US children over time. Higher level of eGFR at the time of transplant is not associated with patient or allograft survival. Implications of the observed trend of performing preemptive kidney transplant at higher eGFR on the long-term health of children deserve further study.

Background

There has been a recent trend toward starting dialysis at higher eGFRs in children, with no identified survival benefits. We aimed to determine whether there are similar trends in the timing of preemptive kidney transplant and whether higher eGFR (≥15 ml/min per 1.73 m2) at preemptive kidney transplant was associated with clinical outcomes among US children.

Methods

We performed a retrospective cohort study of 1514 children in the United States Renal Data System who received a preemptive kidney transplant between 2006 and 2019. In primary analysis, we examined the association between calendar year and eGFR (ml/min per 1.73 m2) at the time of preemptive kidney transplant, categorized as higher (eGFR ≥15) versus lower (eGFR <15) using logistic regressions. The relationship between eGFR at preemptive kidney transplant and graft failure or death was assessed using Cox proportional hazards and Fine–Gray models.

Results

We found a temporal trend in eGFR at preemptive kidney transplant in children; every 5-year increase in calendar period was associated with 55% higher odds (95% confidence interval, 1.35 to 1.79) of receiving a preemptive kidney transplant at higher eGFR. There was no association between preemptive kidney transplant at higher (versus lower) eGFR and risk of allograft failure or death (hazard ratio, 1.12; 95% confidence interval, 0.87 to 1.43) over a median follow-up of 5.7 years.

Conclusions

There has been a trend toward preemptive kidney transplant at higher eGFR over time in children. Receipt of a preemptive kidney transplant at higher eGFR was not associated with allograft or patient survival. Implications of these trends deserve further study.

Performance of enzymatic creatinine methods in the pediatric concentration range

Creatinine is a widely used clinical biomarker in adult and pediatric patients to estimate kidney function and glomerular filtration rate. There are however few recent studies that have addressed method performance in the creatinine range relevant for children. This study aimed to describe measurement performance in the pediatric concentration range by comparing commonly used enzymatic methods on four platforms: Abbott Alinity, Radiometer ABL800, Roche Cobas and Siemens Atellica, to the reference method isotope dilution mass spectrometry (IDMS). A secondary aim was to compare the Roche enzymatic methods by using dilutions of control sera issued by the Nordic Association of Clinical Chemistry. We found varying accuracy of the creatinine methods in the low concentration range. The relative difference between platforms, in an investigated range below 75 µmol/L, decreased as creatinine concentration increased. Using an absolute factor to correct for method bias as recommended by one of the manufacturers could hamper measurement trueness in the low concentration range. The in vitro diagnostic industry and stakeholders should strive towards creatinine measurement agreeability. Attention to the pediatric concentration range is needed when correcting for method bias.

Kidney Function Following COVID-19 in Children and Adolescents

Importance

It remains unclear whether children and adolescents with SARS-CoV-2 infection are at heightened risk for long-term kidney complications.

Objective

To investigate whether SARS-CoV-2 infection is associated with an increased risk of postacute kidney outcomes among pediatric patients, including those with preexisting kidney disease or acute kidney injury (AKI).

Design, Setting, and Participants

This retrospective cohort study used data from 19 health institutions in the National Institutes of Health Researching COVID to Enhance Recovery (RECOVER) initiative from March 1, 2020, to May 1, 2023 (follow-up ≤2 years completed December 1, 2024; index date cutoff, December 1, 2022). Participants included children and adolescents (aged <21 years) with at least 1 baseline visit (24 months to 7 days before the index date) and at least 1 follow-up visit (28 to 179 days after the index date).

Exposures

SARS-CoV-2 infection, determined by positive laboratory test results (polymerase chain reaction, antigen, or serologic) or relevant clinical diagnoses. A comparison group included children with documented negative test results and no history of SARS-CoV-2 infection.

Main Outcomes and Measures

Outcomes included new-onset chronic kidney disease (CKD) stage 2 or higher or CKD stage 3 or higher among those without preexisting CKD; composite kidney events (≥50% decline in estimated glomerular filtration rate [eGFR], eGFR ≤15 mL/min/1.73 m2, dialysis, transplant, or end-stage kidney disease diagnosis), and at least 30%, 40%, or 50% eGFR decline among those with preexisting CKD or acute-phase AKI. Hazard ratios (HRs) were estimated using Cox proportional hazards regression models with propensity score stratification.

Results

Among 1 900 146 pediatric patients (487 378 with and 1 412 768 without COVID-19), 969 937 (51.0%) were male, the mean (SD) age was 8.2 (6.2) years, and a range of comorbidities was represented. SARS-CoV-2 infection was associated with higher risk of new-onset CKD stage 2 or higher (HR, 1.17; 95% CI, 1.12-1.22) and CKD stage 3 or higher (HR, 1.35; 95% CI, 1.13-1.62). In those with preexisting CKD, COVID-19 was associated with an increased risk of composite kidney events (HR, 1.15; 95% CI, 1.04-1.27) at 28 to 179 days. Children with acute-phase AKI had elevated HRs (1.29; 95% CI, 1.21-1.38) at 90 to 179 days for composite outcomes.

Conclusions and Relevance

In this large US cohort study of children and adolescents, SARS-CoV-2 infection was associated with a higher risk of adverse postacute kidney outcomes, particularly among those with preexisting CKD or AKI, suggesting the need for vigilant long-term monitoring.

Opioid prescribing patterns and the effect of chronic kidney disease in pediatric urology population: A retrospective cohort analysis

BACKGROUND

Significant efforts have been undertaken to decrease opioid prescribing, but there is little research into patient-specific factors presenting as barriers in the pediatric surgical population. Non-steroidal anti-inflammatory drugs (NSAIDs) have been shown to be a safe and effective alternative to opioids for pain control, however, concerns about their impact on renal function limit their use in patients with chronic kidney disease (CKD). Data is limited on the interplay of CKD on opioid prescribing.

OBJECTIVE

We hypothesized that opioid reduction efforts were successful, but patients with CKD would be more likely to receive an opioid prescription than those without CKD.

STUDY DESIGN

A retrospective cohort study of patients ≤18 years old undergoing urologic surgery from 2014 to 2022 was performed. Patients were stratified by CKD diagnosis, determined by chart diagnosis and confirmed with CKiD U25 eGFR calculations, excluding those with normal eGFR or Stage 1 CKD. Patients without a documented CKD diagnosis and without preoperative renal function testing were presumed not to have CKD. Patients were propensity matched using the optimal full algorithm across 12 different variables. Outcomes of interest were discharge opioid prescriptions, non-opioid analgesic prescriptions, and unscheduled healthcare encounters (urology clinic visits within 5 days, emergency department visits, readmissions, or reoperations within 30 days).

RESULTS

10,604 patients were included. 603 patients (5.7 %) had a pre-existing CKD diagnosis; the majority were CKD stage 2 (77.8 %, 466 patients). A significant decrease in discharge opioid prescriptions was seen for patients with and without CKD. Patients with CKD had greater opioid exposure prior to surgery (17.2 %, 104 versus 2.8 %, 280, p = 0.04). Those with CKD were equally likely to be prescribed NSAIDs (p = 0.36) and opioids (p = 0.09) at discharge. Patients with CKD were more likely to present to the emergency department (ED) within 30 days of surgery (17.6 % versus 7.9 %, p = 0.007).

DISCUSSION

Similar proportions of patients with and without CKD received an opioid prescription at discharge. Patients with CKD were more likely to be exposed to opioids in-hospital earlier than non-CKD counterparts.

CONCLUSIONS

Multiple interventions and a dedicated postoperative opioid reduction protocol worked well, even in patients with CKD where there is concern about safely receiving NSAIDs. All-cause unplanned healthcare encounters did not differ significantly within groups with introduction of these interventions.

Incomplete concordance between laboratory and pathologic findings on post-induction kidney biopsy in pediatric patients with proliferative lupus nephritis

BACKGROUND

Proliferative lupus nephritis (LN) is associated with increased risk of progression to kidney failure. After initial kidney biopsy, the utility and timing of subsequent biopsies is unknown. There is known discordance between the laboratory parameters used to diagnose LN and the histopathologic classification. We explore the utility of a subsequent kidney biopsy in guiding treatment of LN to determine the factors that warrant follow-up kidney biopsy.

METHODS

We conducted a single center retrospective cohort study of 30 SLE patients who underwent serial kidney biopsy for LN. Subjects were stratified based on their Childhood Arthritis and Rheumatology Research Alliance (CARRA) renal response into complete renal response (CRR) and incomplete renal response (IRR) groups at the time of second biopsy.

RESULTS

Among 30 patients with LN, 11/18 in CRR group and 11/12 in IRR group had persistent proliferative nephritis at 1 ± 0.3 years after initial biopsy. Only SLEDAI score was associated with an increased risk of persistent proliferative nephritis (p = 0.03). Initial CARRA response category was associated with outcome at last follow-up (mean 4.5 years), with 11/18 CRR and 3/12 IRR achieving CRR at last follow-up at mean 4.5 years (p < 0.001). Kidney biopsy directly impacted clinical decision in 7/18 CRR patients in the CRR group who had therapy escalated or reduction withheld due to biopsy findings.

CONCLUSIONS

Available laboratory markers in LN are insufficient to identify children with ongoing proliferative nephritis. Follow-up kidney biopsy may be warranted for children with CRR at 1 year after initial biopsy.

Interval healthcare provider contact and blood pressure control in children with chronic kidney disease and hypertension

BACKGROUND

Prior studies in the CKiD (Chronic Kidney Disease in Children) cohort have shown poor blood pressure (BP) control over time. It is unclear whether the lack of BP control is associated with frequency of provider contact between annual study visits.

METHODS

Six hundred eighty-nine CKiD participants with elevated BP or self-reported history of hypertension contributed longitudinal annual data (2,916 total visits). Provider visits were categorized as any well or sick visit, excluding emergency department visits. Repeated measures logistic regression quantified the association between number of visits over the last year (categorized as 0, 1-2, 3-5, 6-10 or > 10 visits) and BP control (defined as non-elevated BP at an annual CKiD visit). Models were unadjusted, minimally adjusted (controlling for sociodemographic factors), and fully adjusted (additionally controlling for chronic kidney disease (CKD) severity).

RESULTS

Compared to those with no interval healthcare provider visits over the prior year, participants with 3-5 visits had significantly greater odds of BP control across all models (unadjusted, OR 1.45, 95% CI 1.10-1.89; minimally adjusted, OR 1.36, 95% CI 1.03-1.79; fully adjusted, OR 1.36, 95% CI 1.01-1.81); those with fewer or more frequent visits did not consistently have significant improvement in BP control.

CONCLUSIONS

In this cohort of youth with CKD and elevated BP, interval healthcare provider contact of 3-5 visits per year between annual CKiD visits was associated with improved BP control; less and more frequent contact was not, even after adjusting for CKD severity. Optimal frequency of health visits by CKD and comorbidity severity deserves further study.

Association of patent ductus arteriosus treatment in extremely low gestational age neonates with two year kidney outcomes: a secondary analysis of the preterm erythropoietin neuroprotection trial (PENUT)

BACKGROUND

Management of patent ductus arteriosus (PDA) is variable and includes expectant, medical, and procedural options. Both the hemodynamic effects of a PDA and its treatment put neonates at risk for acute kidney injury (AKI). Little is known about how different management approaches to a PDA, either conservative management or active management and either medical or surgical treatment, in preterm neonates impact kidney function over the longer term. The objective of this study is to evaluate rates of kidney dysfunction at two years of age in extremely low gestational age neonates (ELGANs) with treated compared to untreated PDAs.

METHODS

Secondary analysis of prospectively collected data from the PENUT trial. Kidney dysfunction defined by: eGFR < 90 mL/min/1.73 m2, systolic or diastolic blood pressures (SBP or DBP) > 90th percentile, or proteinuria measured by albumin to creatinine ratio (ACR) > 30 mg/g. Between-group, variables were compared using chi-square or t-test statistics. General estimating equations and multivariable logistic regression was used to evaluate the association with outcomes.

RESULTS

Of 780 ELGANs, 261 (43%) were treated for PDA. Of those treated, 168 (64.4%) received pharmacologic treatment, 12 (4.6%) received surgical treatment, 57 (21.8%) received both, and 24 (9.2%) were listed as having a treated PDA without specification of management. After adjusting for confounding factors, those actively treated for a PDA were less likely to have SBP > 90th percentile at two years (29.5% treated vs. 34.3% control, adjusted OR 0.59, CI 0.36-0.99). The adjusted odds-ratios for differences in other 2-year kidney outcomes did not differ. Among those medically treated, indomethacin was used more commonly than either ibuprofen or acetaminophen.

CONCLUSIONS

ELGANs receiving treatment for a PDA were less likely to have elevated SBP at two years. Prospective studies are needed to examine the effects of a hemodynamically significant PDA and its management on long-term kidney outcomes.

Framework for Kidney Health Follow-Up Among Neonates With Critical Cardiac Disease: A Report From the Neonatal Kidney Health Consensus Workshop

Acute kidney injury is common among neonates with critical cardiac disease. Risk factors and associations with kidney-related outcomes are heterogeneous and distinct from other neonates. As survival of children with critical cardiac disease increases to adulthood, the burden of chronic kidney disease is increasing. Thirty percent to 50% of adults with congenital heart disease have impaired kidney function, even in the absence of prior kidney injury episodes. This may be related to the current standardized acute kidney injury criteria, which may not fully capture clinically meaningful kidney injury and long-term kidney health risks. An improved understanding of which neonates with critical cardiac disease should undergo kidney health follow-up is imperative. During the National Institutes of Health-supported Neonatal Kidney Health Consensus Workshop to Address Kidney Health meeting conducted in February 2024, a panel of 51 neonatal nephrology experts focused on at-risk groups: (1) preterm infants, (2) critically ill infants with acute kidney injury, and (3) infants with critical cardiac disease. The critical cardiac disease subgroup, comprising multidisciplinary experts, used a modified Delphi process to achieve consensus on recommendations for kidney health follow-up. In this report, we review available data on kidney health follow-up in critical cardiac disease and summarize the 2 consensus-based recommendations. We introduce novel diagnostic and risk-stratification tools for acute kidney injury diagnosis in neonates with cardiac disease to guide follow-up recommendations. Finally, we identify important knowledge gaps, representing areas of focus for future research. These should be prioritized to understand and improve long-term kidney health in critical cardiac disease.

Renal Autotransplantation for Resection of Bilateral Nephroblastoma and High-Risk Neuroblastoma in Children

BACKGROUND/OBJECTIVES

In bilateral nephroblastoma and high-risk neuroblastoma in children with extensive tumor involvement of the renal vessels or pedicle, complete tumor resection with preservation of healthy renal tissue is not feasible with in situ nephron-sparing surgery or vascular replacement. The aim of this study was to present our experience with ante situ tumor resection and renal autotransplantation (RATX) in these children.

METHODS

A retrospective study of children with bilateral nephroblastoma and high-risk neuroblastoma who underwent tumor resection and RATX at an international referral center for pediatric surgical oncology between 2006 and 2024 was performed. RATX was performed by transection of renal vessels, ante situ mobilization, and perfusion of the kidney with Bretschneider's solution. Tumor resection was performed on a bloodless kidney under hypothermia.

RESULTS

Ante situ tumor resection and RATX were performed at a median age of 36 months (range 13-62) in 4 children with bilateral nephroblastoma and 4 children with high-risk neuroblastoma. Complete tumor resection was achieved in all patients. One patient with neuroblastoma died of sepsis after 14 days. The 7 surviving patients showed no evidence of disease and normal to slightly decreased glomerulofiltration rates at a median follow-up of 20 months (range 3-155). Limitations include the retrospective design, small sample size, and heterogeneity of the study population due to very rare indication.

CONCLUSIONS

Ante situ tumor resection and RATX is a feasible surgical approach for children with multifocal bilateral nephroblastoma or high-risk neuroblastoma who are ineligible for in situ nephron-sparing surgery or vascular reconstruction.

Reduced kidney function in very-low-birth-weight preterm infants at preschool age

BACKGROUND

Very-low-birth-weight (VLBW) infants have significant risk factors for adverse health outcomes. Previous studies have focused on neurological, pulmonary, and cardiovascular complications, but the long-term outcomes of other organ functions particularly kidney function warrant further investigation. This prospective study aimed to compare kidney function between VLBW preterm and term infants at 5-6 years of age.

METHODS

Participants underwent comprehensive assessments of kidney function and blood pressure. Estimated glomerular filtration rates (eGFR) for serum creatinine (Cr) and cystatin C (CysC) were calculated using the CKiD-U25 equations, and comparative analyses conducted between preterm and term groups. In the preterm group, perinatal growth rates of weight and height at various stages were monitored to investigate their potential association with kidney function.

RESULTS

A total of 61 VLBW preterm and 40 term children participated in the study. The preterm group exhibited significantly higher serum CysC levels (0.97 vs. 0.87 mg/L, p = 0.001), lower eGFR-CysC (82.3 vs. 93.0 mL/min/1.73 m2, p < 0.001), and smaller kidney length compared to the term group. Notably, 72% of VLBW preterm children exhibited abnormal eGFR-CysC levels (< 90 mL/min/1.73 m2). Preterm children exhibited significantly higher systolic and diastolic blood pressures, but growth velocities and perinatal characteristics did not significantly affect kidney function at preschool age.

CONCLUSIONS

Kidney function may be diminished in VLBW preterm children at preschool age. However, no significant effects of perinatal risk factors or growth on kidney function were observed. These findings underscore the importance of ongoing long-term monitoring of kidney health in this vulnerable population.

Comparison of three different cystatin C measurement procedures in a pediatric chronic kidney disease cohort: Calibration for longitudinal measurements and implications for clinical estimation of GFR

INTRODUCTION

Serum cystatin C (CysC) is used to estimate glomerular filtration rate (eGFR), including in the Chronic Kidney Disease in Children (CKiD) Under 25 years (U25eGFR) equations. Several CysC measurement procedures available from diagnostic vendors include reference material for calibration, but the extent of heterogeneity across manufacturers is unclear. Since heterogeneity may have clinical and research implications for eGFR, we evaluated three CysC procedures in samples from the CKiD study representing a wide spectrum of kidney function.

MATERIALS AND METHODS

The three CysC measurement procedures evaluated were: Siemens BN II N Latex CystatinC Assay; Gentian CystatinC Immunoassay; and Roche Tina-quant CystatinC Gen.2. Bland-Altman quantified agreement with Siemens as reference because that method was used for longitudinal CKiD samples from 2003 to 2023. We present derivation of the interquartile range (IQR) of U25eGFR as a measure of precision and describe differences outside this range.

RESULTS

From 53 samples from 44 participants, Gentian measurements were 7 % higher than Siemens (95 %CI: +5.6 %,+8.5 %), while Roche measurements were 4.8 % lower on average (95 %CI: -6.2 %,-3.3 %). Both had very high correlation: 0.9926 and 0.9906, respectively. There was strong agreement across procedures, but a simple correction factor of 7 % reduction applied to Gentian yielded unbiased estimates (+0.03 %, 95 %CI: -1.3 %,+1.4 %) and strong performance in Deming regression. For precision, 98 % of U25eGFR values based on Gentian and Roche CysC were each within the IQR of the Siemens-based estimates.

CONCLUSIONS

Despite reference material calibration, heterogeneity across CysC measurement procedures was observed. Procedure variability was within the limits of U25eGFR estimates indicating that practically, all procedures are appropriate for clinical use. Clinicians may consider calculating IQR of U25eGFR estimates for pediatric chronic kidney disease management.

Kidney Outcomes in Children Receiving Extracorporeal Membrane Oxygenation: A Single-Center Acute Cohort From 2009 to 2019, Followed to 2021

OBJECTIVES

Long-term kidney outcomes after extracorporeal membrane oxygenation (ECMO) are little quantified and understood. We aimed to describe the frequency of kidney dysfunction screening during follow-up and the prevalence of long-term kidney disease.

DESIGN

Retrospective cohort of pediatric ECMO patients with estimated glomerular filtration rate (eGFR) (mL/min/1.73 m 2 ) using all post-discharge serum creatinine values to define three kidney outcomes: 1) acute kidney injury (AKI), with eGFR of less than 60 mL/min/1.73 m 2 , which subsequently improved to normal (≥ 90 mL/min/1.73 m 2 ); 2) abnormal eGFR of less than 90 mL/min/1.73 m 2 at last follow-up; and 3) chronic kidney disease (CKD) with eGFR of less than 90 mL/min/1.73 m 2 on at least two occasions separated by greater than or equal to 90 days, without an intervening or subsequently normal eGFR.

SETTING

Single-center tertiary care children's hospital system.

PATIENTS

All pediatric patients surviving ECMO from 2009 to 2019.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

In the 10-year cohort of 666 patients, 399 (60%) survived at least 3 months post-discharge. Of these, 382 of 399 (96%) were followed at our institution for a median of 5 years (interquartile range, 3-8 yr). Two hundred sixty-four of 382 (69%) had at least one creatinine value post-discharge, and 209 of 382 (55%) had at least two values three months apart. Of the 264 with at least one creatinine value, 61 (23%) had an abnormal eGFR; of the 209 with at least two values greater than or equal to 90 days apart, 18 (9%) met criteria for CKD. Of those with CKD, 12 of 18 had AKI during ECMO, and seven of 18 had AKI events post-discharge (range, 1-6 episodes).

CONCLUSIONS

This 2009-2019 pediatric ECMO cohort of survivors, followed for a median of 5 years, shows the subsequent high burden of kidney disease. We found that monitoring and following kidney function was not complete in this population, which is a concern since the rate of later AKI events and CKD is significant. Further study is needed to mitigate this post-ECMO vulnerability.

Cardiorenal syndrome: evolving concepts and pediatric knowledge gaps

Cardiorenal syndrome (CRS) refers to concomitant dysfunction of both the heart and kidneys. The pathology in CRS is bidirectional. Many individuals with kidney disease will develop cardiovascular complications. Conversely, rates of acute kidney injury and chronic kidney disease are high in cardiac patients. While our understanding of CRS has greatly increased over the past 15 years, most research has occurred in adult populations. Improving cardiorenal outcomes in children and adolescents requires increased collaboration and research that spans organ systems. The purpose of this review is to discuss key features of CRS and help bring to light future opportunities for pediatric-specific research.

IPNA consensus definitions for clinical trial outcomes in steroid-resistant nephrotic syndrome

Assessment of the true impact of therapeutic interventions is a challenge in the absence of universal, standardized definitions for clinical trial endpoints in children with kidney diseases. Steroid-resistant nephrotic syndrome (SRNS) is a difficult kidney disease to treat, with unremitting disease progressing to kidney failure. Currently, available therapies result in suboptimal cure rates. Clinical trials with innovative, targeted treatments will likely be conducted for this disease in the foreseeable future. An international consortium of the IPNA Best Practices and Standards Committee and the Pediatric Nephrology Expert Group of the conect4children (c4c) network developed through consensus, standardized, internationally acceptable definitions for trial outcomes for SRNS. The endpoint definitions were formulated for use with urine protein to creatinine ratios and estimated glomerular filtration rates. Definitions of complete remission, partial remission, non-remission of disease, reduction in proteinuria, kidney disease progression, kidney failure, and composite kidney outcome were refined using an iterative process until a consensus was achieved.

Comparative Efficacy of Nonsteroid Immunosuppressive Medications in Childhood Nephrotic Syndrome

Importance

Cyclophosphamide and calcineurin inhibitors are the most used nonsteroid immunosuppressive medications globally for children with various chronic inflammatory conditions. Their comparative effectiveness remains uncertain, leading to worldwide practice variation. Nephrotic syndrome is the most common kidney disease managed by pediatricians globally and suboptimal treatment is associated with high morbidity.

Objective

To evaluate the comparative effectiveness of cyclophosphamide vs calcineurin inhibitors (tacrolimus or cyclosporine) for childhood nephrotic syndrome relapse prevention.

Design, Setting, and Participants

Using target trial emulation methods, the study team emulated a pragmatic, open-label clinical trial using available data from the Insight Into Nephrotic Syndrome: Investigating Genes, Health, and Therapeutics (INSIGHT) study. INSIGHT is a multicenter, prospective cohort study in the Greater Toronto Area, Canada. Participants included children (1 to 18 years) with steroid-sensitive nephrotic syndrome diagnosed between 1996 and 2019 from the Greater Toronto Area, who initiated cyclophosphamide or a calcineurin inhibitor treatment. Data analysis was performed in 2024.

Exposures

Incident cyclophosphamide or calcineurin inhibitor treatment. Randomization was emulated by overlap weighting of propensity scores for treatment assignment.

Main Outcomes

The primary outcome was time to relapse, analyzed by weighted Kaplan-Meier and Cox proportional hazards models. Secondary outcomes included relapse rates, subsequent immunosuppression, kidney function, hypertension, adverse events, and quality of life.

Results

Of 578 children (median age at diagnosis, 3.7 [IQR, 2.8-6.0] years; 371 male [64%] and 207 female [36%]), 252 initiated cyclophosphamide, 131 initiated calcineurin inhibitors, and 87 sequentially initiated both medications. Baseline characteristics were well balanced after propensity score weighting. During median 5.5-year (quarter 1 to quarter 3, 2.5-9.2) follow-up, there was no significant difference in time to relapse between calcineurin inhibitor vs cyclophosphamide treatment (hazard ratio [HR], 1.25; 95% CI, 0.84-1.87). Relapses were more common after calcineurin inhibitor treatment than cyclophosphamide (85% vs 73%) in the weighted cohorts, but not statistically significant. There were also no significant differences in subsequent relapse rates, nonsteroid immunosuppression use, or kidney function between medications. Calcineurin inhibitor treatment was associated with more hospitalizations (HR, 1.83; 95% CI, 1.14-2.92) and intravenous albumin use (HR, 2.81; 95% CI, 1.65-4.81).

Conclusions and Relevance

In this study, there was no evidence of difference in time to relapse after cyclophosphamide and calcineurin inhibitor treatment in children with nephrotic syndrome. Cyclophosphamide treatment is shorter in duration and more accessible globally than calcineurin inhibitors.

Switching to the CKD-EPI but Not Modified FAS eGFR Formula Underdetects CKD Among Adolescents and Young Adults in México

BACKGROUND

Guidelines recommend switching the glomerular filtration rate (eGFR) estimation from the CKiD-U25 to the CKD-EPI formula at age 18. We investigated how this would affect chronic kidney disease (CKD) classification.

METHODS

Serum creatinine was enzymatically measured in 1061 samples from 914 community-based 10-23-year-olds from Tlaxcala, Mexico, a region where urinary biomarkers demonstrated early kidney damage associated with exposure to inorganic toxins in a pediatric population. We calculated their eGFR using CKiD-U25, modified Schwartz, the first and modified Pottel full-age spectrum (FAS), and CKD-EPI formulae. Correlation analysis characterized the CKD stage stratified by age and sex.

RESULTS

At baseline, the median age was 13 (IQR: 12, 15) years, and 55% were female. Median CKiD-U25 eGFR was 96.9 (IQR: 83.3, 113.3) mL/min/1.73 m2, significantly lower than the CKD-EPI eGFR, which was 140.8 (IQR: 129.9, 149.3) mL/min/1.73 m2 (p < 0.0001, Wilcoxon rank test). The mean bias was 36.99 ± 12.89 mL/min/1.73 m2. Pearson correlation was r = 0.8296 (95% confidence interval 0.0898-0.8474). There was a better correlation between the modified Schwartz (r = 0.9421 (0.9349, 0.9485)) and the Pottel FAS (r = 0.9299 (0.9212, 0.9376)) formulae. Agreement was deficient when the eGFR was >75 mL/min/1.73 m2 in younger age and female sex. Modified Schwartz identified 281 (26.4%) measurements as having CKD 2 and 3 (2+), U25 identified 401 (37.7%) measurements as having CKD 2+, FAS identified 267 (25.1%) and modified FAS identified 282 (30%) measurements as having CKD 2+, and CKD-EPI identified 51 (4.8%) measurements as having CKD 2+, respectively.

CONCLUSIONS

In this population, there needed to be better agreement between the various eGFR formulae. CKD-EPI identifies substantially fewer at-risk participants as having CKD.

Metabolic acidosis is associated with infection severity in pediatric pyelonephritis and pneumonia

BACKGROUND

Pyelonephritis is the most common serious bacterial infection in pediatric patients. Several electrolyte abnormalities have been described with pyelonephritis, including metabolic acidosis. We sought to describe the frequency and clinical significance of metabolic acidosis in pediatric patients with acute Escherichia coli (E. coli) pyelonephritis, with comparison to parallel infection group of bacterial pneumonia.

METHODS

This was a single-center, retrospective study of pediatric patients with pyelonephritis or pneumonia hospitalization. Nadir serum bicarbonate and anion gap values were collected, and baseline and recovery values when available. Serum electrolyte and creatinine values and markers of infection severity were recorded.

RESULTS

Ninety-four pyelonephritis and 95 pneumonia subjects were included. Pyelonephritis mean nadir bicarbonate was 20 (SD 3) mEq/L, statistically significantly lower than 21 (3) mEq/L in pneumonia. Corresponding anion gap was 16 (4) mEq/L in pyelonephritis, statistically significantly lower than 17 (3) mEq/L in pneumonia. There was significant correlation between acidosis and number of fever days in pyelonephritis and between acidosis and hospital length of stay in both groups.

CONCLUSIONS

This study demonstrated development of acidosis in 84% of patients with pyelonephritis and in 66% with pneumonia. The mechanism of acidosis appears to have a greater contribution from elevated anion gap in the pneumonia group compared to the pyelonephritis group. Lower nadir serum bicarbonate values are associated with longer hospital length of stay in both groups and greater number of fever days in the pyelonephritis patients.

Cobalamin Deficiency in Children and Adolescents with Sickle Cell Disease

Background/Objective: Cobalamin (B12) deficiency is reported in 18% of adults with sickle cell disease (SCD) and only 10% without SCD; limited data are available on children. Diagnosing B12 deficiency is challenging given the lack of an established gold standard method of assessment and the unique renal features of SCD. B12 metabolism can be impacted by the clinical use of nitrous oxide gas (N2O), which is a standard therapy for SCD pain in some European countries. In response to emerging reports of neurologic sequalae in patients with SCD receiving N2O, we evaluated the prevalence of B12 deficiency in children with SCD pain. Methods: Secondary analysis of prospective blood and urine samples in children aged 3-21 hospitalized with SCD pain. B12 deficiency was defined as plasma methylmalonic acid (MMA) > 592 nmol/L or urine MMA/creatinine ≥ 2.2 mmol/mol. Results: Ninety-four children (13 ± 4 years, 54% female, 68% hemoglobin-SS, and 72% on hydroxyurea) were assessed. Further, 53% (50/94) had B12 deficiency diagnosed by either urine, plasma, or both; 27% (25/94) were deficient based on urine; 39% (37/94) were deficient by plasma; and 13% (12/94) were deficient by both plasma and urine. Plasma MMA and urine MMA/creatinine did not correlate with hemoglobin or mean corpuscular volume. Conclusions: B12 deficiency was common in children with SCD. The absence of a gold standard for diagnosing B12 deficiency compounded with the reliability issues of testing modalities make it impractical to determine whether this is an over- or under-estimation of the true prevalence. Future studies to better understand the dynamics of B12 metabolism during acute and steady states in SCD are warranted and could elucidate the influence of acute SCD pain on these biomarkers.

KDIGO 2024 Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease in Children and Adults: a commentary from the European Renal Best Practice (ERBP)

The Kidney Disease: Improving Global Outcomes (KDIGO) 2024 Guideline for Identification and Management of Chronic Kidney Disease (CKD) is a welcome development, coming 12 years after the paradigm-changing 2012 guidelines. We are living in an unprecedented era in nephrology with novel therapies, including sodium-glucose cotransporter-2 inhibitors, glucagon-like peptide-1 receptor agonists and non-steroidal mineralocorticoid receptor antagonists, now being proven in multiple randomized controlled clinical trials to reduce both the progression of CKD and cardiovascular morbidity and mortality. The KDIGO 2024 CKD Guideline is aimed at a broad audience looking after children and adults with CKD and provide practical and actionable steps to improve care. This commentary reviews the guideline sections pertaining to the evaluation and risk assessment of individuals with CKD from a European perspective. We feel that despite the last guideline being published 12 years ago, and the fact that the assessment of CKD has been emphasized by many other national/international nephrology, cardiology and diabetology guidelines and societies, the diagnosis and treatment of CKD remains poor across Europe. As such, the KDIGO 2024 CKD Guideline should be seen as an urgent call to action to improve diagnosis and care of children and adults with CKD across Europe. We know what we need to do. We now need to get on and do it.

Age-Related Changes in Brain Structure in Pediatric Chronic Kidney Disease

Importance

Pediatric patients with chronic kidney disease (CKD) exhibit reduced cerebellum volume, which is associated with neurocognitive deficits and a lower estimated glomerular filtration rate (eGFR), even before dialysis or transplantation. These differences have not been examined within the context of age-related brain changes during childhood to early adulthood.

Objective

To evaluate differences in age-related neurodevelopmental changes in patients with CKD compared with control participants and to investigate associations between regional neuroanatomy, functional outcomes, and disease-related variables.

Design, Setting, and Participants

Case-control study of individuals aged 6 through 21 years with and without CKD at an academic medical center in Iowa City, Iowa, from September 2016 to August 2024.

Exposures

Neurocognitive testing; 3-T magnetic resonance imaging.

Main Outcomes and Measures

Participants completed standardized neurocognitive assessments and quantitative neuroanatomical scans. Brain regions of interest (ROIs) were analyzed for volumetric differences using automated pipelines. Multivariable linear models assessed neurocognitive and neuroanatomical differences between groups, including an age × group interaction for ROI analyses.

Results

The sample included 124 individuals (mean [SD] age, 12.8 [4.5] years; 74 [59.7%] male), including 87 control participants (44 [50.6%] male) and 37 participants with CKD (30 [81.1%] male). The mean (SD) eGFR was 71.3 [25.5] mL/min/1.73 m2 for the CKD group. Participants with CKD scored lower than control participants on most neurocognitive measures included in the analyses. The CKD group showed differential age-related changes in cerebellar gray matter (β = -0.10; 95% CI, -0.18 to -0.01; Cohen f = 0.22) and white matter (β = -0.09; 95% CI, -0.19 to -0.00; Cohen f = 0.19). The age × group interaction approached but did not reach significance for amygdala volume (β = 0.09; 95% CI, -0.01 to 0.19; Cohen f = 0.18; P = .06). Volumetric variation in these regions was associated with proxy ratings of executive function in patients with CKD. A significant, positive association between cerebellar gray matter and eGFR was observed in the CKD group (β = 0.04; 95% CI, 0.00 to 0.02; P = .01).

Conclusions and Relevance

In this case-control study, age-related neurodevelopmental differences were observed in pediatric patients with CKD compared with healthy peers. Reductions in cerebellar volume were associated with cognitive deficits and lower kidney function. These findings underscore the importance of monitoring neurodevelopmental trajectories in children with CKD, as early interventions may be necessary to mitigate cognitive impairments associated with CKD.

Acute kidney injury is associated with abnormal cefepime exposure among critically ill children and young adults

BACKGROUND

Elevated cefepime blood concentrations can cause neurotoxicity in adults. The consequences of elevated cefepime concentrations among pediatric patients are unknown. Future exploration of such effects requires first identifying patients at risk for elevated cefepime exposure. We investigated the role of acute kidney injury as a risk factor for increased cefepime concentrations in critically ill children.

METHODS

This was a retrospective analysis at a single pediatric intensive care unit. Analyzed patients received at least 24 h of cefepime and had at least two opportunistic samples collected for total cefepime concentration measurement. Individual pharmacokinetic (PK) profiles during treatment courses were reconstructed using Bayesian estimation with an established population PK model. Elevated trough concentration (Cmin) was defined as ≥ 30 mg/L based on adult toxicity studies. The effect of kidney dysfunction on cefepime PK profiles was interrogated using a mixed-effect model.

RESULTS

Eighty-seven patients were included, of which 13 (14.9%) had at least one estimated Cmin ≥ 30 mg/L. Patients with elevated Cmin were more likely to have acute kidney injury (AKI) during their critical illness (92% vs. 57%, p = 0.015 for any AKI; 62% vs. 26%, p = 0.019 for severe AKI). Patients who had AKI during critical illness had significantly higher cefepime exposure, as quantified by the area under the concentration-time curve over 24 h (AUC24h) and Cmin.

CONCLUSIONS

Among critically ill children, AKI is associated with elevated cefepime concentrations. Identifying these high-risk patients is the first step toward evaluating the clinical consequences of such exposures.

KDIGO 2024 Guidelines-Key Points for Pediatricians

This Viewpoint summarizes key takeaways for pediatricians from the 2024 Kidney Disease: Improving Global Outcomes guidelines.

KDOQI US Commentary on the KDIGO 2024 Clinical Practice Guideline for the Evaluation and Management of CKD

The Kidney Disease Outcomes Quality Initiative (KDOQI) convened a work group to review the 2024 KDIGO (Kidney Disease: Improving Global Outcomes) guideline for the management of chronic kidney disease (CKD). The KDOQI Work Group reviewed the KDIGO guideline statements and practice points and provided perspective for implementation within the context of clinical practice in the United States. In general, the KDOQI Work Group concurs with several recommendations and practice points proposed by the KDIGO guidelines regarding CKD evaluation, risk assessment, and management options (both lifestyle and medications) for slowing CKD progression, addressing CKD-related complications, and improving cardiovascular outcomes. The KDOQI Work Group acknowledges the growing evidence base to support the use of several novel agents such as sodium/glucose cotransporter 2 inhibitors for several CKD etiologies, and glucagon-like peptide 1 receptor agonists and nonsteroidal mineralocorticoid receptor antagonists for type 2 CKD in setting of diabetes. Further, KDIGO guidelines emphasize the importance of team-based care which was also recognized by the work group as a key factor to address the growing CKD burden. In this commentary, the Work Group has also assessed and discussed various barriers and potential opportunities for implementing the recommendations put forth in the 2024 KDIGO guidelines while the scientific community continues to focus on enhancing early identification of CKD and discovering newer therapies for managing kidney disease.

Supporting Transgender, Nonbinary, and Gender Diverse Youth During Solid Organ Transplantation

As gender diversity becomes more understood and accepted in mainstream culture, medical systems and health care providers must learn to provide comprehensive and affirming care to gender diverse individuals. As the number of gender diverse pediatric patients continues to grow, these patients will be cared for by pediatric solid-organ transplant programs. This review summarizes the basic principles of gender-affirming care and describes how transplant teams can provide equitable and affirming care to young gender diverse patients undergoing solid organ transplant (SOT). In addition, this review uses kidney transplant as a framework to explore gender-affirming hormone therapy and gender-affirming surgery in the setting of transplant, laboratory value interpretation in gender diverse individuals, and the importance of an individualized approach in care of the gender diverse transplant recipient.

Sodium glucose co-transporter 2 inhibitors (SGLT2i) for pediatric kidney disease: the future is near

The sodium glucose co-transporter 2 (SGLT2) functions in the proximal tubule to reabsorb the bulk of filtered glucose. SGLT2 inhibitors have been developed to promote renal glucose excretion to improve glycemic control in diabetes. Regulatory guidance mandated adequately powered studies to detect increased cardiovascular risk from emerging hypoglycemic medications. This led to recognition of remarkable improvement in cardiovascular and kidney outcomes with SGLT2 inhibition. Moreover, cardiovascular and kidney benefits extend beyond patients with diabetes. The dramatic kidney benefits of SGLT2 inhibitors documented in CKD in adult patients underscores the need for pediatric nephrologists to familiarize themselves with SGLT2 inhibitor therapies. This review explores the currently available body of knowledge regarding the kidney protective effects of SGLT2 inhibitors in adults and mechanisms thought to contribute to improved kidney outcomes. The limited data for SGLT2i treatment in pediatric kidney disease are reviewed and highlight the need for randomized controlled trials of this drug class in pediatric kidney patients as has been done for pediatric diabetes. Dosing patterns for SGLT2 inhibitors from other pediatric settings are reviewed as well as guidance for initiating SGLT2 inhibition in young adults remaining in pediatric nephrology care.