The use of plasma creatinine concentration for estimating glomerular filtration rate in infants, children, and adolescents

Risk factors for surgery in children with ureteropelvic junction obstruction due to antenatally detected ınfantil hydronephrosis

BACKGROUND

Although the majority of cases with antenatally detected hydronephrosis (ANH) resolve during postnatal period; patients should be monitored for the risk of developing ureteropelvic junction obstruction (UPJO) which requires surgical intervention. We aimed to define independent risk factors for operation in whom diagnosis of UPJO was precisely proven with histopathological evidence.

METHODS

Medical files of 155 children (186 renal units) with anteroposterior pelvic diameter (APPD) ≥ 7 mm or ≥ 1SFU (Society of Fetal Urology) grade of pelvicalyceal dilatation were retrospectively investigated. Patients who underwent pyeloplasty and whose pathological examinations of resected ureteral samples confirmed obstruction, were compared to non-interventional group in terms of demographics, serum creatinine, APPD, SFU grade, cortical thickness and diuretic renogram. Multiple regression models were used to predict independent risk factors for pyeloplasty.

RESULTS

155 patients (186 renal units) were recruited for the study. Pyeloplasty was performed in 50(32.2%) patients. Increased APPD, T1/2 and Tmax values with low parenchymal thickness and DRF were demonstrated in operated patients compared to those who did not. Significant decrease in APPD and T1/2 values and also significant improvement in parenchymal thickness were observed in conservatively managed group. Multivariate analysis revealed high APPD measurements and time activity curve patterns to be associated with significantly increased likelihood of surgical intervention.

CONCLUSIONS

There is still an ongoing debate on which screening method should be used for the accurate diagnosis of UPJO or the indications for surgical intervention. Baseline APPD and diuretic renogram curve were found to be significant in predicting surgery for UPJO.

A comparison of health-related quality of life between continuous ambulatory peritoneal dialysis and automated peritoneal dialysis in children with stage 5 chronic kidney disease in Thailand: a randomized controlled trial

BACKGROUND

Improving health-related quality of life (HRQoL) is one of the main goals in managing stage 5 chronic kidney disease (CKD). However, limited evidence compares HRQoL between continuous ambulatory peritoneal dialysis (CAPD) and automated peritoneal dialysis (APD) in children. This open-label randomized controlled trial (RCT) aimed to compare HRQoL in pediatric patients with stage 5 CKD receiving CAPD vs. APD in Thailand.

METHODS

Children with stage 5 CKD were randomized 1:1 to receive APD or CAPD. The primary outcome was HRQoL, measured by EQ-5D-5L, EQ-5D-3L, and PedsQL at baseline, week 16 and week 48. Outcomes were analyzed using linear mixed models.

RESULTS

A total of 60 patients were recruited: 30 with CAPD and 30 with APD. General characteristics, utility scores measured by EQ-5D and HRQoL score measured by PedsQL were comparable between both groups at baseline. During follow-up, no significant differences in terms of utility and HRQoL scores could be identified at week 16 and week 48. Although the children in the APD group seemed to have more favorable changes in some PedsQL domains of PedsQL (school and social domain), as compared to the CAPD group, it was not found that the improvement from baseline was significantly different between both groups.

CONCLUSIONS

No significant benefit of APD was found over CAPD in terms of HRQoL improvement. However, larger studies are warranted along with qualitative studies to examine the complete impacts of APD on HRQoL among pediatric patients with stage 5 CKD and their families.

Chronic kidney disease in Syrian children: a single center experience

BACKGROUND

Chronic kidney disease (CKD) is a condition marked by permanent kidney damage, which can eventually advance to kidney failure. Our study aimed to identify CKD causes and investigate the risk factors for CKD progression in Syrian children.

METHODS

A single-center observational cohort study was conducted at Children's University Hospital in Damascus, included all patients admitted to the department of pediatric nephrology (inpatient unit) from February 2022 to February 2023, with CKD stages 2-5.

RESULTS

Our study included 100 patients, with a slight female predominance, and mean age of 4.73 years ± 3.7, ranging from 3 months to 14 years. CKD causes were congenital anomalies of the kidney and urinary tract (CAKUT) in 79%, hereditary nephropathies in 12%, and glomerular diseases in 9%. After one year of follow-up, 38% of them were stable on conservative management and 62% had kidney failure. Gender, age, and family history of CKD were not statistically significant factors in CKD progression. The progression rate to kidney failure was highest in glomerular diseases, with 100% for glomerulonephritis and 80% for steroid-resistant nephrotic syndrome, and the progression rate in kidney dysplasia patients was 78.1%. Proteinuria, metabolic acidosis, hyperparathyroidism, hypertension, anemia, and hyperphosphatemia were significantly associated with CKD progression.

CONCLUSIONS

In Syrian children, CAKUT are the leading cause of CKD. CKD progression is most rapid in glomerular diseases. Modifiable risk factors, especially hypertension and proteinuria, play a significant role in CKD progression, which highlights the importance of early detection and appropriate management of these factors.

Tacrolimus or Mycophenolate Mofetil for Frequently Relapsing or Steroid-Dependent Nephrotic Syndrome: A Randomized Clinical Trial

Importance

Both tacrolimus (TAC) and mycophenolate mofetil (MMF) are recommended for children with frequently relapsing nephrotic syndrome (FRNS) or steroid-dependent nephrotic syndrome (SDNS). However, their comparative effectiveness and safety have not been evaluated through randomized clinical trials.

Objective

To compare the effectiveness and safety of TAC and MMF in children with FRNS or SDNS.

Design, Setting, and Participants

In this multicenter, open-label randomized clinical trial conducted at 12 pediatric nephrology centers across China, 270 children aged 2 to 18 years with FRNS or SDNS were allocated at a 1:1 ratio to treatment with either TAC or MMF. The study was conducted from November 2019 to July 2023, and data analysis was completed from July 2023 to March 2024.

Intervention

Patients received either TAC (0.025-0.050 mg/kg, orally twice daily) or MMF (10-15 mg/kg, orally twice daily) for 1 year, along with a tapering regimen of steroids.

Main Outcomes and Measures

The primary end point was 1-year relapse-free survival. Relapse frequency, cumulative steroid dosage, and safety profiles were also evaluated.

Results

A total of 292 patients from 12 care centers were assessed for eligibility, and 270 patients were randomized to receive either TAC (n = 135) or MMF (n = 135). Among 270 patients, median (IQR) age was 6.91 (4.25-9.96) years, and 70 patients (25.9%) were female. Compared with MMF, the 1-year relapse-free survival rate in the TAC group was 1.86-fold higher (hazard ratio [HR], 2.86; 95% CI, 1.79-4.76; P < .001) in the intention-to-treat analysis. This difference was also significant after adjusting for the per-protocol analysis (HR, 2.78; 95% CI, 1.72-4.55; P < .001). The mean (SD) time to first relapse was significantly longer in the TAC group (323.99 [98.33] days) compared to the MMF group (263.21 [132.84] days). Furthermore, the TAC group showed a lower annual relapse rate than the MMF group (17.78% vs 41.48%) and required a significantly lower mean (SD) cumulative steroid dose (0.22 [0.10] mg/kg/day vs 0.34 [0.22] mg/kg/day). The safety profile was similar in both groups.

Conclusions and Relevance

In this randomized clinical trial, compared with MMF, a 1-year course of TAC therapy significantly extended the period of relapse-free survival in children with FRNS or SDNS.

Trial Registration

ClinicalTrials.gov Identifier: NCT04048161.

Identification of risk factors for renal progression in adults with IgAV: a retrospective cohort study of a single center in northwest China

OBJECTIVES

This investigation sought to examine the clinical and pathological characteristics, outcomes, and risk factors linked to the progression of renal function in adult-onset immunoglobulin A (IgA) vasculitis within a single center in northwest China.

METHODS

Data were retrospectively gathered from cases of adult-onset IgA vasculitis recorded at a tertiary hospital in northwest China, covering the period from January 2013 to August 2024. During the follow-up, clinical information was compared between patients who advanced to chronic kidney disease (CKD) stage 3 and those who did not.

RESULTS

A sum of 1082 adult-onset IgA vasculitis patients (632 men; median age of 37 years) were included. Among patients with baseline proteinuria >0.5 g/24h (43.9%), 40.7% progressed to chronic kidney disease (CKD) stage 3, while 5.1% developed end-stage renal disease (ESRD). COX regression analysis indicated that older age, renal pathological grade IV, hypertension (HTN), diabetes, hyperlipidemia, and hyperuricemia were independent risk factors for CKD stage 3 progression in individuals with adult-onset IgA vasculitis.

CONCLUSIONS

Older age and comorbidities such as hypertension and diabetes significantly increase the risk of renal progression in adult-onset IgAV. Early management of these comorbidities may mitigate the risk of CKD progression.

Native kidney and graft survival in a cohort of Egyptian children with nephropathic cystinosis: national referral center experience

BACKGROUND

Nephropathic Cystinosis is a rare autosomal recessive lysosomal storage disorder. In addition to kidney dysfunction, this disorder can also affect other organs, such as the eyes, thyroid, muscles, and central nervous system.

METHODS

The current cross-sectional study included 56 patients with nephropathic cystinosis to evaluate the clinical outcome in nephropathic cystinosis patients cohort with regarding kidney function and the need for kidney replacement therapy. Clinical and laboratory data were collected.

RESULTS

Among the 56 patients in our study, 32 (57.1%) were male. Furthermore, 52 (92%) of these patients were offspring of consanguineous marriage. Patients' mean age was 116.96 ± 54.1 months, and the mean onset of nephropathic cystinosis suggestive symptoms was 7.63 ± 3.2 months. In addition, the mean age of confirmed diagnosis was 45.38 ± 35.3 months, and the mean age of end-stage kidney disease (ESKD) was 104 ± 25.7 months. Eighteen patients (32.1%)underwent hemodialysis, whereas 12 patients (21.4%) underwent kidney transplantation. When comparing siblings within the same family, we observed a significant difference in the age at diagnosis. The median age for the first sibling was 60 months, while it was 24 months for the second sibling (p-value = 0.031). Additionally, there were significant differences in weight, chronic kidney disease (CKD) stage, and outcome.

CONCLUSION

Improvement in the awareness and the accessibility to diagnosis over years, early sibling screening, and kidney transplantation have a significant impact on the survival of both patients and kidney in children with nephropathic cystinosis.

Urinary biomarkers in prediction of subclinical acute kidney injury in pediatric oncology patients treated with nephrotoxic agents

BACKGROUND

Acute kidney injury (AKI) is a common complication in pediatric oncology patients, most often caused by nephrotoxic drugs. We aimed to assess whether levels of urinary kidney injury molecule-1 (uKIM-1), neutrophil gelatinase-associated lipocalin (uNGAL), liver fatty acid binding protein (uL-FABP) and Vanin-1 (uVNN-1), individually and in combination-integrated could be early markers for cytotoxic treatment induced AKI.

METHODS

Children with different malignant diseases treated with cisplatin (CIS) or ifosfamide (IFO) were included. AKI was defined using pediatric KDIGO (Kidney Disease Improving Global Outcomes) criteria by comparing pretreatment serum creatinine (sCr) values with those acquired at 48 h after the first or second chemotherapy cycle. Five serum (at baseline, 2, 6, 24 and 48 h after treatment) and four urine samples (at baseline, 2, 6 and 24 h after treatment) were obtained. Urinary biomarkers (uBm) were normalized to urine creatinine.

RESULTS

Thirty-eight patients were assessed. Within 48 h following chemotherapy 6 (15.79%) patients experienced AKI. Patients with AKI were younger and tend to have lower baseline sCr values than patients without AKI, but these differences were not statistically significant. Compared to baselines, all uBm were significantly increased during the first 6 h while sCr concentrations did not change significantly during the study period. The median increases in uBm during the first 6 h after treatment were 529.8% (interquartile range - IQR, 63.9-1835.2%) - 2194.0% (IQR, 255.3-4695.5%) in AKI vs. 302.2% (IQR 114.6-561.2%) -429.8% (156.5-1467.0%) in non-AKI group depending of tested uBm. The magnitude of these changes over time didn't differ significantly between groups. The area under receiver operator curve (AUC) for uL-FABP and uNGAL at 24 h after chemotherapy were 0.81 and 0.72, respectively. The ROC analysis revealed that the other individual biomarkers' performance at any time-point wasn't statistically significant (AUC < 0.7). A model of integrated-combined uBm, 2 h (AUC 0.78), 6 h (AUC 0.85) and 24 h after (AUC 0.92) treatment with CIS and/or IFO showed good utility for early AKI prediction.

CONCLUSIONS

The results of this study support that the use of the uBm to improves early AKI prediction in patients receiving CIS and/or IFO containing chemotherapy. Further studies on larger comparable groups of patients are needed.

Dental caries, oral hygiene and salivary characteristics in children with chronic kidney disease: a case-control study

BACKGROUND

The aim of this study was to compare the oral health findings and salivary parameters of children with different stages of chronic kidney disease (CKD) with those of healthy peers.

METHODS

Intraoral examinations were performed on 43 children aged 8-17 years with CKD and 40 healthy controls from the same pediatric nephrology clinic. Oral health was assessed using the DMFT/dft indices (decayed-missing-filled-teeth), debris index (DI), calculus index (CI), and simplified oral hygiene index (OHI-S). Saliva samples from the children were analyzed for salivary flow rate (SFR), pH, buffering capacity (BC), total oxidant status (TOS), total antioxidant capacity (TAOC), urea, creatinine (Cr), calcium (Ca), potassium (K), phosphorus (P), and salivary α-amylase (SAA). Spearman's rho coefficient was used to examine the relationship between salivary and serum biomarkers levels and oral health findings.

RESULTS

While the DMFT/dft scores were lower in children with CKD (p = 0.001), DI, CI, and OHI-S scores were higher in healthy peers (p < 0.001). Children with CKD had lower SFR, Ca, and TAOC levels, and higher BC, pH, urea, Cr, K, P, TOS, and SAA levels (p < 0.001) compared to healthy controls. Later stages of CKD was associated with the lower dft ( r s = - 0.35; p = 0.022).

CONCLUSIONS

Children with CKD exhibit fewer caries and poorer oral hygiene compared to their healthy peers, and their saliva characteristics differ significantly from those of the healthy group. Disease-related changes in serum and salivary characteristics affect the oral health of children with CKD, necessitating collaboration between pediatric nephrologists and dentists.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT06578832).

Fetal bilateral hyperechogenic kidneys: Prenatal progression and long-term postnatal outcome

OBJECTIVE

To determine the prenatal progression and long-term outcome of fetal bilateral hyperechogenic kidneys (HK).

DESIGN

Retrospective study 2005-2016. Fetal/maternal demographics, scan findings, postnatal diagnoses and outcomes were collected from electronic patient records and post-mortem reports.

RESULTS

Data available for 65 out of 72 fetuses with bilateral HK. Forty-five (69 %) had normal amniotic fluid index (AFI); of these, 23 had isolated HK and all survived the neonatal period. The remaining patients with normal AFI had other renal and multi-system anomalies; diagnoses included 13 trisomies and genetic syndromes - only one patient with suspected bladder outlet obstruction survived. Of 20 pregnancies with reduced AFI, HK were isolated in 5 fetuses, and only one survived (diagnosed with 17q12 microdeletion). The remaining 15 fetuses had multisystem anomalies and none survived; diagnoses included Meckel-Gruber Syndrome and Dandy-Walker malformation. Survival with bilateral HK and oligohydramnios was 5 %. Overall survival was 25/65 (38 %); follow-up data was available for 23 patients. HK resolved in 17 (74 %) and persisted in 6 children, who were followed-up for median 15 years (4-19 years). Of these, 3 patients developed bilateral renal cysts and were diagnosed with HNF1b/17q12 deletion kidney disease (one patient is in CKD2a, whereas the rest have normal renal function). The remaining patients were found to have a PKD1 variant; bilateral renal cysts (lost to follow-up before a genetic diagnosis) and a unilateral hydronephrosis: all have normal renal function.

CONCLUSION

Isolated HK with normal AFI is associated with survival past the neonatal period and normal renal function in most cases (96 %). As normal kidney function may be due to glomerular hyperfiltration in early childhood to teenage years, long-term follow up is advisable, in particular for those with a genetic diagnosis that predisposes to chronic renal impairment in adulthood (HNF1b, 17q12 deletion in this study). HK in the presence of reduced AFI carries a poor prognosis, with only 5 % survival (this patient had 17q12 deletion related kidney disease). Overall survival in this study was 38 % in the first year and 34 % long-term.

An innocent bystander or a predisposing culprit? Kidney injury following pediatric liver transplantation

BACKGROUND

Survival after pediatric liver transplantation has increased dramatically over the years, revealing extra-hepatic complications including impaired kidney function. We conducted a large single-center retrospective study to evaluate kidney outcomes after pediatric liver transplantation.

METHODS

From electronic charts of 121 children who underwent liver transplantation during 2007-2020, we collected pre- and post-transplant data. We investigated the presence of post-transplant permanent kidney injury, including proteinuria, hypertension, and decreased estimated glomerular filtration rate (eGFR). We excluded children who died, underwent liver-kidney transplantation, or had less than 1 year of follow-up.

RESULTS

During a median follow-up of 5.1 (interquartile range 2.9-7.3) years, eGFR decreased, mostly in the first year post-transplant. In addition, 41% of the children presented with acute kidney injury. At their last follow-up, 35% showed permanent kidney injury (hypertension 13%, proteinuria 36%, and eGFR < 90 mL/min per 1.73 m2 7%). Kidney ultrasounds were abnormal for 44% of the children at the last visit, compared to 11% before transplant (p < 0.001). In multivariate analysis, abnormal kidney ultrasound before transplant (odds ratio = 4.53, 95% CI 1.1-18.7) and liver disease with potential risk of primary kidney involvement (odds ratio = 4.77, 95% CI 1.58-14.4) were predictors for hypertension or decreased eGFR at the last follow-up.

CONCLUSIONS

The high prevalence of kidney injury after pediatric liver transplantation and the pretransplant predictors for kidney injury highlight the importance of a thorough kidney pretransplant evaluation and follow-up.

Subclinical systolic dysfunction in children with steroid-resistant nephrotic syndrome identified by speckle tracking echocardiography

BACKGROUND

Steroid resistant nephrotic syndrome (SRNS) is a clinical phenotype of nephrotic syndrome (NS) that does not respond to steroid therapy and usually results in kidney failure. The aim of this study was to determine whether children with SRNS have subclinical left ventricular systolic dysfunction and, if so, to identify the risk factors for myocardial involvement in those children.

METHODS

This prospective case-control study included of 35 children with SRNS, 40 children in the healthy control group, and 40 children with NS during the initial episode as the diseased control group. Conventional echocardiography, tissue Doppler imaging (TDI), and speckle tracking echocardiography (STE) were performed on all the studied children.

RESULTS

No statistically significant difference in conventional echocardiography's parameters were detected between the patient and control groups. TDI revealed that the E/E' ratio was significantly greater in the SRNS group than in both the healthy and diseased control groups (P = 0.001). The left ventricle global longitudinal strain (LV GLS) was markedly lower in children with SRNS than in healthy controls and NS patients (the diseased controls) (P = 0.001). Multiple binary regression analysis for the predictors of systolic dysfunction in SRNS patients revealed that the serum albumin is the only variable that predicts systolic dysfunction in these children.

CONCLUSIONS

Subclinical systolic and diastolic LV dysfunction should be screened in NS especially SRNS children.

IPNA clinical practice recommendations for the diagnosis and management of children with IgA nephropathy and IgA vasculitis nephritis

IgA nephropathy and IgA vasculitis with nephritis, albeit rare, represent two relatively frequent glomerular conditions in childhood. Compared to adults, pediatric IgA nephropathy has a more acute presentation, most frequently with synpharyngitic macrohematuria and histologically with more intense inflammation and less intense chronic damage. Management of these conditions is controversial and supported by little high-quality evidence. The paucity of evidence is due to the disease heterogeneity, its inter-ethnic variability, and the difficulty of extrapolating data from adult studies due to the peculiarities of the condition in children. IgA vasculitis with nephritis is a kidney manifestation of a systemic disorder, typical of the pediatric age, in which both the diagnosis of kidney involvement and its management are poorly defined, and an interdisciplinary approach is crucial. Both conditions can have a profound and long-lasting impact on kidney function and the global health of affected children. The International Pediatric Nephrology Association has therefore convened a diverse international group of experts from different disciplines to provide guidance on the recommended management of these conditions in children and to establish common definitions and define priorities for future high-quality, evidence-based collaborative studies for the benefit of children.

Investigation of Teicoplanin Trough Concentrations and Safety Following High-Dose Loading in a Pediatric Population

BACKGROUND

Therapeutic drug monitoring-informed teicoplanin dosage adjustments are recommended for safe and effective use. The authors' group previously reported that only half of children reached the recommended blood concentration range at the standard teicoplanin loading dose. It has been suggested that higher loading doses are necessary; however, the usefulness and safety of high-dose loading in pediatric patients in clinical practice are unknown.

METHODS

This retrospective cohort study was conducted between January 2018 and June 2021 using electronic medical records. The analysis included 2- to 16-year-old patients treated with teicoplanin who met the eligibility criteria. We assessed the trough concentration of teicoplanin and its safety after high-dose loading in pediatric patients.

RESULTS

Overall, 86 patients received a high-dose loading regimen (15 mg/kg every 12 hours for 3 doses, followed by 10 mg/kg once daily). Notably, 55 of the 86 patients (64%) achieved the target trough concentration (>15 mg/L) at significantly higher rates without increasing the incidence of organ damage compared with the standard loading regimen. Multivariate analysis revealed significant differences in age and renal function as factors that inhibited the attainment of the target trough concentration. Simulation analysis using a nomogram stratified by age and renal function revealed that the predicted teicoplanin trough levels were within the target trough values in 73% of patients.

CONCLUSIONS

High-dose teicoplanin loading safely increases trough blood concentrations in the pediatric population. For further optimization, the dose selection should be stratified according to age and renal function.

A multicenter study investigating the genetic analysis of childhood steroid-resistant nephrotic syndrome: Variants in COL4A5 may not be coincidental

This study aimed to discuss the pathogenic hereditary factors of children with steroid-resistant nephrotic syndrome (SRNS) in Guangxi, China. We recruited 89 patients with SRNS or infantile NS from five major pediatric nephrology centers in Guangxi, and conducted a retrospective analysis of clinical data. Whole-exome sequencing analysis was also performed on all patients. The risk of progression to chronic kidney disease (CKD) was assessed using the Kaplan-Meier method and Cox proportional hazards model. The study included 69 male and 20 female participants from 86 distinct families, with the median age of disease onset being 48 months (interquartile range: 24-93). Overall, 24.7% had a family history of SRNS, whereas 13.5% exhibited extra-kidney manifestations. We identified disease-causing variants in 24.7% (22/89) of patients across eight screened genes. The most frequently detected variant was found in COL4A5, followed by NPHS2 (5.6%), NPHS1 (2.2%), PAX2 (2.2%), WT1 (1.1%), LMX1B (1.1%), NUP105 (1.1%), and COL4A6 (1.1%). Twelve of the 26 pathogenic variants were determined to be de novo. Based on gene detection results, pathogenic variants were categorized into two groups: identified and unidentified variants. The identified variant group demonstrated a significant association with positive family history, steroid resistant-style, and response to immune therapy (P<0.001). Patients with the identified genetic variant were approximately ten times more likely to develop CKD (P<0.001) than those in the unidentified group at the last follow-up. Kidney biopsy was performed on 66 patients, and minimal change disease was the most prevalent histopathological diagnosis (29 cases; 32.6%). These findings suggest that children diagnosed with SRNS exhibit a diverse range of genetic alterations. We identified the COL4A5 variant as the predominant genetic abnormality and a low frequency of NPHS1 gene involvement in these children. Gene variants may serve as an independent predictor for SRNS progression to CKD.

Nephrocalcinosis tendency does not worsen under burosumab treatment for X-linked hypophosphatemic rickets: a multicenter pediatric study

Background

X-linked hypophosphatemic rickets (XLH) is associated with uninhibited FGF23 activity, which leads to phosphaturia, hypophosphatemia and depressed active vitamin D (1,25OH2D) levels. Conventional treatment with phosphate supplements and vitamin D analogs may lead to hypercalciuria (HC), nephrocalcinosis (NC) and hyperparathyroidism. We investigated the effects of burosumab treatment, an anti-FGF23 monoclonal antibody recently approved for XLH, on these complications.

Methods

This retrospective study included children with XLH who were treated with burosumab for at least one year at one of three referral centers. Clinical and biochemical potential treatment outcomes were regularly followed, including multiple urine calcium measurements and NC severity score (0 = no NC, 3 = worse NC).

Results

Twenty-six (13 male) children aged 7.6 ± 3.9 years were followed for 27.5 ± 9.6 months. Mean serum phosphate levels rapidly increased from 2.67 ± 0.61 at baseline to 3.57 ± 0.53 mg/dL after 3 months (p < 0.001) and remained stable thereafter. Concomitant decreases were observed in phosphaturia, serum alkaline phosphatase and parathyroid hormone. HC (U-Ca/Cr > 0.2 mg/mg) was detected in 2/26 (7.7%) patients before burosumab initiation, resolved in one and persisted, albeit improved, in the second. Two patients were newly diagnosed with HC, 15 and 3 months after therapy, which persisted in one of them despite dose reduction attempts. Seven patients had NC at baseline (mean score: 1.8 ± 0.34), but none showed deterioration or developed new NC.

Conclusion

In children with XLH treated with burosumab, HC was an infrequent side effect and preexisting NC did not worsen.

Physiologically Based Pharmacokinetic Modeling of Vancomycin in Critically Ill Neonates: Assessing the Impact of Pathophysiological Changes

Dosing vancomycin for critically ill neonates is challenging owing to substantial alterations in pharmacokinetics (PKs) caused by variability in physiology, disease, and clinical interventions. Therefore, an adequate PK model is needed to characterize these pathophysiological changes. The intent of this study was to develop a physiologically based pharmacokinetic (PBPK) model that reflects vancomycin PK and pathophysiological changes in neonates under intensive care. PK-sim software was used for PBPK modeling. An adult model (model 0) was established and verified using PK profiles from previous studies. A neonatal model (model 1) was then extrapolated from model 0 by scaling age-dependent parameters. Another neonatal model (model 2) was developed based not only on scaled age-dependent parameters but also on quantitative information on pathophysiological changes obtained via a comprehensive literature search. The predictive performances of models 1 and 2 were evaluated using a retrospectively collected dataset from neonates under intensive care (chictr.org.cn, ChiCTR1900027919), comprising 65 neonates and 92 vancomycin serum concentrations. Integrating literature-based parameter changes related to hypoalbuminemia, small-for-gestational-age, and co-medication, model 2 offered more optimized precision than model 1, as shown by a decrease in the overall mean absolute percentage error (50.6% for model 1; 37.8% for model 2). In conclusion, incorporating literature-based pathophysiological changes effectively improved PBPK modeling for critically ill neonates. Furthermore, this model allows for dosing optimization before serum concentration measurements can be obtained in clinical practice.

[Establishment of a population pharmacokinetic model for linezolid in neonates with sepsis]

OBJECTIVES

To establish the pharmacokinetic model of linezolid in neonates, and to optimize the administration regimen.

METHODS

A prospective study was conducted among 64 neonates with sepsis who received linezolid as anti-infective therapy, and liquid chromatography-tandem mass spectrometry was used to measure the plasma concentration of the drug. Clinical data were collected, and nonlinear mixed effects modeling was used to establish a population pharmacokinetic (PPK) model. Monte Carlo simulation and evaluation was performed for the optimal administration regimen of children with different features.

RESULTS

The pharmacokinetic properties of linezolid in neonates could be described by a single-compartment model with primary elimination, and the population typical values for apparent volume of distribution and clearance rate were 0.79 L and 0.34 L/h, respectively. The results of goodness of fit, visualization verification, and the Bootstrap method showed that the model was robust with reliable results of parameter estimation and prediction. Monte Carlo simulation results showed that the optimal administration regimen for linezolid in neonates was as follows: 6 mg/kg, q8h, at 28 weeks of gestational age (GA); 8 mg/kg, q8h, at 32 weeks of GA; 9 mg/kg, q8h, at 34-37 weeks of GA; 11 mg/kg, q8h, at 40 weeks of GA.

CONCLUSIONS

The PPK model established in this study can provide a reference for individual administration of linezolid in neonates. GA and body weight at the time of administration are significant influencing factors for the clearance rate of linezolid in neonates.

Therapeutic drug monitoring of linezolid in Chinese premature neonates: a population pharmacokinetic analysis and dosage optimization

This study aimed to develop a pharmacokinetic model of linezolid in premature neonates and evaluate and optimize the administration regimen. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to detect the blood concentration data of 54 premature neonates after intravenous administration of linezolid, and the relevant clinical data were collected. The population pharmacokinetic (PPK) model was established by nonlinear mixed effects modeling. Based on the final model parameters, the optimal administration regimen of linezolid in premature neonates with different body surface areas (BSA) was simulated and evaluated. The pharmacokinetic properties of linezolid in premature neonates are best described by a single-compartment model with primary elimination. The population typical values for apparent volume of distribution and clearance were 0.783 L and 0.154 L/h, respectively. BSA was a statistically significant covariate with clearance (CL) and volume of distribution (Vd). Monte Carlo simulations showed that the optimal administration regimen for linezolid in premature neonates was 6 mg/kg q8h for BSA 0.11 m2, 7 mg/kg q8h for BSA 0.13 m2, and 9 mg/kg q8h for BSA 0.15 m2 with minimum inhibitory concentration (MIC) ≤1 mg/L, 7 mg/kg q8h for BSA 0.11 m2, 8 mg/kg q8h for BSA 0.13 m2, and 10 mg/kg q8h for BSA 0.15 m2 with MIC = 2 mg/L. A pharmacokinetic model was developed to predict the blood concentration on linezolid in premature neonates. Based on this model, the optimal administration regimen of linezolid in premature neonates needs to be individualized according to different BSA levels.

Associations between the Serum Triglyceride Level and Kidney Outcome in Patients with Chronic Kidney Disease: The Fukuoka Kidney disease Registry Study

AIMS

Hypertriglyceridemia is a risk factor for chronic kidney disease (CKD). However, whether or not it predicts the risk of CKD progression is unknown. This study evaluated the association between serum triglyceride (TG) levels and kidney disease progression in patients with non-dialysis-dependent CKD.

METHODS

The Fukuoka Kidney disease Registry (FKR) study was a multicenter, prospective longitudinal cohort study. In total, 4,100 patients with CKD were followed up for 5 years. The primary outcome was the incidence of CKD progression, defined as a ≥ 1.5-fold increase in serum creatinine level or the development of end-stage kidney disease. The patients were divided into quartiles according to baseline serum TG levels under non-fasting conditions: Q1 ＜87 mg/dL; Q2, 87-120 mg/dL; Q3, 121-170 mg/dL, and Q4 ＞170 mg/dL.

RESULTS

During the 5-year observation period, 1,410 patients met the criteria for CKD progression. The multivariable-adjusted Cox proportional hazards model showed a significant association between high serum TG level and the risk of CKD progression in the model without macroalbuminuria as a covariate (multivariable hazard ratio[HR] for Q4 versus Q1, 1.20; 95% CI, 1.03-1.41; P=0.022), but the significance disappeared after adjusting for macroalbuminuria (HR for Q4 versus Q1, 1.06; 95% CI, 0.90-1.24; P=0.507).

CONCLUSIONS

The present findings suggest that individuals with high serum TG levels are more likely to develop CKD progression than those without; however, whether or not higher serum TG levels reflect elevated macroalbuminuria or lead to CKD progression via elevated macroalbuminuria is unclear.

Treatment Outcomes and Associated Factors of Intravenous Colistin for Nosocomial Infections in Pediatric Patients: A Retrospective Study in a University Hospital in Thailand

BACKGROUND

This study aimed to investigate the efficacy and safety of intravenous colistin in pediatric patients with nosocomial Gram-negative bacteria infections and to determine factors associated with treatment outcomes.

METHODS

This retrospective study recruited patients <18 years of age receiving intravenous colistin between January 2014 and December 2018. Clinical data and treatment outcomes were reviewed, and factors associated with treatment outcomes were assessed.

RESULTS

This study included 178 patients with a median age of 3.4 years (range, 0.1-17.8). The mean ± SD dose of colistin prescribed to patients without renal impairment was 5.1 ± 0.6 mg/kg/day. The clinical response rate was 70.8% in patients receiving colistin for specific treatment. Infection-related mortality and crude mortality were 17.5% and 19.7%, respectively. The nephrotoxicity rate was 29.8%; approximately 70% of the episodes occurred between the 3rd and 7th day of treatment. The presence of at least 2 organ dysfunctions [adjusted hazard ratio (aHR): 7.17; 95% CI: 1.64-31.40], septic shock (aHR: 2.69; 95% CI: 1.36-5.32) and receiving chemotherapy/immunosuppressants (aHR: 2.68; 95% CI: 1.36-5.25) were observed to be associated with clinical failure. The factors observed to be associated with nephrotoxicity included hypoalbuminemia (aHR: 2.93; 95% CI: 1.26-6.78), receiving amphotericin B (aHR: 2.29; 95% CI: 1.16-4.52), vancomycin (aHR: 3.36; 95% CI: 1.50-7.56) and vasopressors (aHR: 2.57; 95% CI: 1.27-5.21).

CONCLUSION

Colistin is generally effective in the treatment of nosocomial Gram-negative bacteria infections in pediatric patients. Close monitoring of renal function should be considered, especially in high-risk patients. Optimal dosage regimens for pediatric populations to promote more favorable clinical outcomes and minimize nephrotoxicity require further investigation.

Application of machine-learning models to predict the ganciclovir and valganciclovir exposure in children using a limited sampling strategy

Intravenous ganciclovir and oral valganciclovir display significant variability in ganciclovir pharmacokinetics, particularly in children. Therapeutic drug monitoring currently relies on the area under the concentration-time (AUC). Machine-learning (ML) algorithms represent an interesting alternative to Maximum-a-Posteriori Bayesian-estimators for AUC estimation. The goal of our study was to develop and validate an ML-based limited sampling strategy (LSS) approach to determine ganciclovir AUC0-24 after administration of either intravenous ganciclovir or oral valganciclovir in children. Pharmacokinetic parameters from four published population pharmacokinetic models, in addition to the World Health Organization growth curve for children, were used in the mrgsolve R package to simulate 10,800 pharmacokinetic profiles of children. Different ML algorithms were trained to predict AUC0-24 based on different combinations of two or three samples. Performances were evaluated in a simulated test set and in an external data set of real patients. The best estimation performances in the test set were obtained with the Xgboost algorithm using a 2 and 6 hours post dose LSS for oral valganciclovir (relative mean prediction error [rMPE] = 0.4% and relative root mean square error [rRMSE] = 5.7%) and 0 and 2 hours post dose LSS for intravenous ganciclovir (rMPE = 0.9% and rRMSE = 12.4%). In the external data set, the performance based on these two sample LSS was acceptable: rMPE = 0.2% and rRMSE = 16.5% for valganciclovir and rMPE = -9.7% and rRMSE = 17.2% for intravenous ganciclovir. The Xgboost algorithm developed resulted in a clinically relevant individual estimation using only two blood samples. This will improve the implementation of AUC-targeted ganciclovir therapeutic drug monitoring in children.

Clinical implications of primary "occult" vesicoureteral reflux in male children

OBJECTIVES

To compare characteristics and outcomes of vesicoureteral reflux (VUR) detected solely on isotopic cystography (IC) ("occult" VUR) with voiding cystourethrography (VCUG)-detected VUR.

MATERIALS AND METHODS

Between 2015 and 2020, we retrospectively enrolled all male children first undergoing VCUG and, if negative, IC in the same session. Kidney injury (KI) was defined by abnormal estimated glomerular filtration rate and/or blood pressure and/or proteinuria.

RESULTS

We enrolled 421 males with a median age of 3 months and a follow-up of 5.3 years. None exhibited KI initially, but 10% of those with VUR developed KI during follow-up. Two hundred and twenty-two patients (52.7%) did not show VUR, 152 (36.1%) had VCUG-diagnosed VUR, and 47 (11.2%) had occult VUR. Therefore, 47/199 patients (23.6%) with VUR had occult VUR. Among these, 34/47 (72.3%) had dilated VUR, and 22/47 (46.8%) exhibited split renal function < 45% and/or scar (scintigraphic damage). Compared to patients with occult VUR, those with VCUG-diagnosed VUR showed a similar prevalence of febrile urinary tract infection (fUTI) before and after VUR diagnostics and KI at the last follow-up but a higher prevalence of dilated VUR, of scintigraphic damage, and underwent surgery more frequently. At multiple logistic regression analysis, patients with VCUG-diagnosed VUR presented an increased risk of fUTI either before or after VUR diagnosis and of KI, while patients with occult VUR presented an increased risk of fUTI before (and among patients with dilated VUR also after) VUR diagnosis and of KI.

CONCLUSION

Occult VUR affects 23.6% of male children with VUR with a non-negligible risk of VUR-associated KI and fUTI. IC could select, among males with recurrent fUTIs and negative VCUG, those requiring surgery for a possible dilated occult VUR.

CLINICAL RELEVANCE STATEMENT

Vesicoureteral reflux may be overlooked in 25% of boys during VCUG, yet they are at risk of fUTIs and KI. In case of recurrent infections post-negative cystourethrography, IC could detect occult reflux, guiding surgical intervention.

Is there a relationship between hyperchloremia status and the risk of developing acute kidney injury in pediatric patients with diabetic ketoacidosis?

Diabetic ketoacidosis (DKA) is a life-threatening complication of type 1 diabetes mellitus (T1DM). Prerenal acute kidney injury (AKI) is associated with profound hypovolemia and reduced renal perfusion. Results regarding hyperchloremia-associated AKI in patients with DKA are conflicting; we therefore investigated the potential relationship between hyperchloremia status and the risk of developing AKI. This single-center cohort study included 113 newly diagnosed T1DM patients with DKA admitted to the pediatric intensive care unit. Laboratory parameters, including Na, K, urea, creatinine, and chloride levels, were retrospectively reviewed at the time of presentation and at 12, 24 and 36 h. AKI was defined using the eGFR according to the pediatric RIFLE classification criteria. Twenty-two (19.5%) of the 113 patients were in the AKI group. Two-way repeated-measures ANOVA showed significant (P values ≤ 0.01) time interaction effects within the groups based on the eGFR and the serum chloride, hyperchloremia, and phosphate levels. Serum chloride levels did not differ between the groups during the first 12 h (p > 0.05) but were significantly greater in the AKI group than in the non-AKI group at 24 h and 36 h (p < 0.01). The final DKA resolution time was significantly greater in the AKI group than in the non-AKI group [22.2 (9.5) vs. 17.0 (12.0) h, respectively; p = 0.03]. However, the groups had similar lengths of hospital stay [13.0 (8.0) days vs. 12.0 (4.0) days, respectively; p = 0.17].Conclusions: Hyperchloremia may be iatrogenic rather than causative during treatment. This may worsen renal failure and prolong the recovery and treatment time for DKA patients. What is Known? • Acute kidney injury resulting from severe volume depletion is a common occurrence in diabetic ketoacidosis and typically requires significant volume replacement therapy. • In recent years, hyperchloremia has been associated with increased risks of AKI, morbidity, and mortality in some conditions, such as diabetic ketoacidosis. What is New? • The incidence of hyperchloremia increases over time during the treatment of diabetic ketoacidosis. • Hyperchloremia may be an iatrogenic element rather than a cause of acute kidney injury during the treatment of diabetic ketoacidosis.

Optimal dosing regimen of caspofungin in adolescents with allogeneic haematopoietic stem cell transplantation

OBJECTIVES

The optimal dosing regimen of caspofungin in adolescents undergoing allogeneic haematopoietic stem cell transplantation against Candida spp. is unknown. The study aimed to compare body surface area (BSA)-based and fixed dosing regimens through population pharmacokinetic (PPK) analysis and to optimize dosing regimens likely to achieve therapeutic exposures.

METHODS

Opportunistic sampling was used to collect plasma concentrations through a prospective observational pharmacokinetic study. PPK analysis and Monte Carlo simulations (n = 1000) were performed using NONMEM.

RESULTS

A total of 86 samples of 30 adolescents (12-17 years old) were best described by a two-compartment pharmacokinetic model. BSA is the only covariate on clearance and central volume of distribution. For Candida glabrata and Candida albicans, a standard dosing regimen could achieve at least a 90% probability of target attainment for the indicator of AUC0-24/MIC90. Dosing regimen simulations identified a BSA cut-off value of 1.3 m2, where a fixed loading dose (LD) is preferred when BSA ≥ 1.3 m2 and a BSA-based LD is preferred when BSA < 1.3 m2. For maintenance dose (MD), however, the BSA-based dose was proposed, regardless of BSA. The current maximum dosing regimen of LD 70 mg/day and MD 70 mg/day could not result in sufficient antifungal exposure for Candida parapsilosis with MIC90 of 1 mg/L. Furthermore, an LD of 70 mg/day and MD of 60 mg/m2/day rendered 90.4% steady-state trough concentration (Ctrough) over 1 mg/L in the virtual population.

CONCLUSIONS

Our study proposed optimized dosing regimens of caspofungin based on AUC0-24/MIC90 or Ctrough, which may support further individualized treatment.

Postdiscontinuation Antibiotic Exposure in Hospitalized Infants at Risk for Late-onset Sepsis in the Neonatal Intensive Care Unit

BACKGROUND

In the neonatal intensive care unit, infants are at risk for late-onset sepsis. When blood cultures are negative, antibiotic stewardship efforts encourage stopping antibiotics, yet the duration of therapeutic exposure after the last dose is unknown.

METHODS

This retrospective cohort study of simulated antibiotic exposures used published population pharmacokinetic models within drug-specific neonatal intensive care unit cohorts of preterm and term infants, postnatal age 7-60 days and exposed to cefepime, piperacillin-tazobactam or tobramycin. Monte Carlo simulations (NONMEM 7.3) were used to predict steady-state exposures after a 72-hour antibiotic course per Neofax dosing. Exposure was assessed relative to drug-specific minimum inhibitory concentration (MIC) targets between 1 and 16 mcg/mL for Pseudomonas and Enterobacteriaceae species. Postdiscontinuation antibiotic exposure (PDAE) was defined as the time from the last dose to when antibiotic concentration decreased below a specific MIC.

RESULTS

Piperacillin-tazobactam, cefepime and tobramycin cohorts included infants with median gestation age 29, 32 and 32 weeks and postnatal age 17, 19 and 15 days, respectively. The mean PDAE was 19-68 hours, depending on the specific antibiotic/MIC combination. PDAE was longer for infants <28 days old and preterm (vs. term) infants. Cefepime exhibited the longest mean PDAE of 68 hours for Enterobacteriaceae MIC 1. Piperacillin mean PDAE was 25 hours for Enterobacteriaceae MIC 8. Tobramycin had a short mean PDAE of 19 hours.

CONCLUSIONS

Piperacillin and cefepime exposures remained therapeutic long after the expected 8- to 12-hour dosing interval. PDAE is an important consideration for antibiotic stewardship among hospitalized infants, particularly premature infants and those within 1 month postbirth.

Glomerular basement membrane ultrastructural changes in a patient with COQ2 glomerulopathy: A case report

Primary coenzyme Q10 deficiency-1, caused by COQ2 disease-causing variants, is an autosomal recessive disorder, and genetic testing is the gold standard for diagnosing this condition. A Chinese boy with steroid-resistant nephrotic syndrome, focal segmental glomerulosclerosis, and progressive kidney insufficiency was included in the study. Electron microscopy revealed the glomerular basement membrane with irregular thickness and lamellation with diffuse effacement of foot processes in the podocytes, and swollen mitochondria with abnormal cristae in the podocytes. Coenzyme Q10 supplementation started about 3 weeks after the onset of mild kidney dysfunction did not improve the proband's kidney outcome. Proband-only whole-exome sequencing and Sanger sequencing revealed two heteroallelic COQ2 variants: a maternally inherited novel variant c.1013G > A[p.(Gly338Glu)] in exon 6 and a variant of unknown origin c.1159C > T[p.(Arg387*)] in exon 7. Subsequent long-read sequencing demonstrated these two variants were located on different alleles. Our report extends the phenotypic and genotypic spectrum of COQ2 glomerulopathy.

Acute Kidney Injury in Children: A Focus for the General Pediatrician

Acute kidney injury (AKI) presents significant challenges in pediatric care, often remaining underrecognized. This paper provides an overview of pediatric AKI, highlighting its epidemiology, pathophysiology, diagnosis, predisposing conditions, and treatment. AKI in children stems from diverse causes, including renal tubular damage, vasoconstriction, and inflammation. Diagnosis relies on traditional markers such as serum creatinine and urine output, alongside emerging biomarkers such as Cystatin C, NGAL, KIM-1, IL-18, TIMP-2 and IGFBP7, urinary calprotectin, URBP4, L-FABP, and clusterin. Various pediatric conditions predispose to AKI, including type 1 diabetes, pneumonia, bronchiolitis, appendicitis, gastroenteritis, COVID-19, multisystem inflammatory syndrome, sickle cell disease, and malignancies. Treatment entails supportive care with fluid management and, in severe cases, renal replacement therapy. Timely recognition and management are essential to mitigating adverse outcomes. Enhanced awareness and integration of novel biomarkers could improve pediatric AKI care, warranting further research for better diagnosis and management.

Efficacy and Safety of Allopurinol on Chronic Kidney Disease Progression: A Systematic Review and Meta-Analysis

OBJECTIVE

Hyperuricemia is associated with the progression of chronic kidney disease (CKD). Whether urate-lowering treatment with allopurinol can delay disease progression remains controversial.

METHODS

Relevant databases were searched. Randomized clinical trials comparing the efficacy and -safety of allopurinol in patients with CKD were selected. The primary outcomes were changes in serum uric acid concentration and estimated glomerular filtration rate (eGFR). Random-effects modeling was used to -calculate the standard mean difference (SMD) with 95% CIs.

RESULTS

Four trials enrolling 698 participants were included. All were 2-arm parallel trials with a mean duration follow-up of 22.5 months. Congenital anomalies of the kidney and urinary tract were the most common cause of CKD in children, whereas diabetes was the leading cause of CKD in adults. Allopurinol significantly increased the eGFR compared with control groups (SMD, 2.04; 95% CI, 0.60-3.49; p = 0.005; I2 = 98.23%). Allopurinol led to a significant decrease in serum uric acid concentration compared with the control group (SMD, -5.16; 95% CI, -8.31 to -2.01; p = 0.001; I2 = 98.80%). No significant difference in adverse effects was identified between treatment and control groups.

CONCLUSIONS

Allopurinol treatment in patients with CKD and hyperuricemia slows the decline in eGFR as compared with placebo, without risk of increased adverse effects.

Population pharmacokinetics and dose rationale for aciclovir in term and pre-term neonates with herpes

Aciclovir is considered the first-line treatment against Herpes simplex virus (HSV) infections in new-borns and infants. As renal excretion is the major route of elimination, in renally-impaired patients, aciclovir doses are adjusted according to the degree of impairment. However, limited attention has been given to the implications of immature renal function or dysfunction due to the viral disease itself. The aim of this investigation was to characterize the pharmacokinetics of aciclovir taking into account maturation and disease processes in the neonatal population. Pharmacokinetic data obtained from 2 previously published clinical trials (n = 28) were analyzed using a nonlinear mixed effects modeling approach. Post-menstrual age (PMA) and creatinine clearance (CLCR) were assessed as descriptors of maturation and renal function. Simulation scenarios were also implemented to illustrate the use of pharmacokinetic data to extrapolate efficacy from adults. Aciclovir pharmacokinetics was described by a one-compartment model with first-order elimination. Body weight and diagnosis (systemic infection) were statistically significant covariates on the volume of distribution, whereas body weight, CLCR and PMA had a significant effect on clearance. Median clearance varied from 0.2 to 1.0 L/h in subjects with PMA <34 or ≥34 weeks, respectively. Population estimate for volume of distribution was 1.93 L with systemic infection increasing this value by almost 3-fold (2.67 times higher). A suitable model parameterization was identified, which discriminates the effects of developmental growth, maturation, and organ function. Exposure to aciclovir was found to increase with decreasing PMA and renal function (CLCR), suggesting different dosing requirement for pre-term neonates.

Development of a tool for predicting HNF1B mutations in children and young adults with congenital anomalies of the kidneys and urinary tract

BACKGROUND

We aimed to develop a tool for predicting HNF1B mutations in children with congenital abnormalities of the kidneys and urinary tract (CAKUT).

METHODS

The clinical and laboratory data from 234 children and young adults with known HNF1B mutation status were collected and analyzed retrospectively. All subjects were randomly divided into a training (70%) and a validation set (30%). A random forest model was constructed to predict HNF1B mutations. The recursive feature elimination algorithm was used for feature selection for the model, and receiver operating characteristic curve statistics was used to verify its predictive effect.

RESULTS

A total of 213 patients were analyzed, including HNF1B-positive (mut + , n = 109) and HNF1B-negative (mut - , n = 104) subjects. The majority of patients had mild chronic kidney disease. Kidney phenotype was similar between groups, but bilateral kidney anomalies were more frequent in the mut + group. Hypomagnesemia and hypermagnesuria were the most common abnormalities in mut + patients and were highly selective of HNF1B. Hypomagnesemia based on age-appropriate norms had a better discriminatory value than the age-independent cutoff of 0.7 mmol/l. Pancreatic anomalies were almost exclusively found in mut + patients. No subjects had hypokalemia; the mean serum potassium level was lower in the HNF1B cohort. The abovementioned, discriminative parameters were selected for the model, which showed a good performance (area under the curve: 0.85; sensitivity of 93.67%, specificity of 73.57%). A corresponding calculator was developed for use and validation.

CONCLUSIONS

This study developed a simple tool for predicting HNF1B mutations in children and young adults with CAKUT.

Meropenem Disposition in Neonatal and Pediatric Extracorporeal Membrane Oxygenation and Continuous Renal Replacement Therapy

This study aimed to characterize the impact of extracorporeal membrane oxygenation (ECMO) on the pharmacokinetics (PK) of meropenem in neonates and children and to provide recommendations for meropenem dosing in this specific population of patients. Therapeutic drug monitoring (152 meropenem plasma concentrations) data from 45 patients (38 received ECMO) with a body weight (BW) of 7.88 (3.62-11.97) kg (median (interquartile range)) and postnatal age of 3 (0-465) days were collected. The population PK analysis was performed using NONMEM V7.3.0. Monte Carlo simulations were performed to assess the probability of target achievement (PTA) for 40% of time the free drug remained above the minimum inhibitory concentration (fT > MIC) and 100% fT > MIC. BW was found to be a significant covariate for the volume of distribution (Vd) and clearance (CL). Additionally, continuous renal replacement therapy (CRRT) was associated with a two-fold increase in Vd. In the final model, the CL and Vd for a typical patient with a median BW of 7.88 kg that was off CRRT were 1.09 L/h (RSE = 8%) and 3.98 L (14%), respectively. ECMO did not affect meropenem PK, while superimposed CRRT significantly increased Vd. We concluded that current dosing regimens provide acceptably high PTA for MIC ≤ 4 mg/L for 40% fT > MIC, but individual dose adjustments are needed for 100% fT > MIC.

Estimated glomerular filtration rate in clinical practice: Consensus positioning of the Brazilian Society of Nephrology (SBN) and Brazilian Society of Clinical Pathology and Laboratory Medicine (SBPC/ML)

Chronic kidney disease (CKD) represents one of today's main public health problems. Serum creatinine measurement and estimation of the glomerular filtration rate (GFR) are the main tools for evaluating renal function. There are several equations to estimate GFR, and CKD-EPI equation (Chronic Kidney Disease - Epidemiology) is the most recommended one. There are still some controversies regarding serum creatinine measurement and GFR estimation, since several factors can interfere in this process. An important recent change was the removal of the correction for race from the equations for estimating GFR, which overestimated kidney function, and consequently delayed the implementation of treatments such as dialysis and kidney transplantation. In this consensus document from the Brazilian Societies of Nephrology and Clinical Pathology and Laboratory Medicine, the main concepts related to the assessment of renal function are reviewed, as well as possible existing controversies and recommendations for estimating GFR in clinical practice.

Prospective validation of an equation based on plasma cystatin C for monitoring the glomerular filtration rate in children treated with cisplatin or ifosfamide for cancer

We recently proposed an equation to estimate the glomerular filtration rate (GFR) in children with cancer based on plasma cystatin C and serum creatinine levels together with body weight (the "CysPed equation"). The current clinical study reports a prospective evaluation of this equation in 18 children treated by nephrotoxic chemotherapy. The CysPed equation resulted in less bias and greater precision compared to two equations previously proposed equations by Schwartz, with or without plasma cystatin C. Moreover, the decrease in GFR due to chemotherapy was clearly identified by the CysPed equation. This equation may be used to monitor the renal function in childhood cancer units.

When will the Glomerular Filtration Rate in Former Preterm Neonates Catch up with Their Term Peers?

AIMS

Whether and when glomerular filtration rate (GFR) in preterms catches up with term peers is unknown. This study aims to develop a GFR maturation model for (pre)term-born individuals from birth to 18 years of age. Secondarily, the function is applied to data of different renally excreted drugs.

METHODS

We combined published inulin clearance values and serum creatinine (Scr) concentrations in (pre)term born individuals throughout childhood. Inulin clearance was assumed to be equal to GFR, and Scr to reflect creatinine synthesis rate/GFR. We developed a GFR function consisting of GFRbirth (GFR at birth), and an Emax model dependent on PNA (with GFRmax, PNA50 (PNA at which half ofGFR max is reached) and Hill coefficient). The final GFR model was applied to predict gentamicin, tobramycin and vancomycin concentrations.

RESULT

In the GFR model, GFRbirth varied with birthweight linearly while in the PNA-based Emax equation, GA was the best covariate for PNA50, and current weight for GFRmax. The final model showed that for a child born at 26 weeks GA, absolute GFR is 18%, 63%, 80%, 92% and 96% of the GFR of a child born at 40 weeks GA at 1 month, 6 months, 1 year, 3 years and 12 years, respectively. PopPK models with the GFR maturation equations predicted concentrations of renally cleared antibiotics across (pre)term-born neonates until 18 years well.

CONCLUSIONS

GFR of preterm individuals catches up with term peers at around three years of age, implying reduced dosages of renally cleared drugs should be considered below this age.

Renal angina index for early identification of risk of acute kidney injury in critically ill children

BACKGROUND

The main objective was to test whether the Renal Angina Index (RAI), calculated on patient admission to the pediatric intensive care unit (PICU), is associated with the risk of acute kidney injury (AKI) based on the Kidney Disease: Improving Global Outcomes (KDIGO) (stage ≥ 2) in 72 h. The specific aim was to analyze the performance of the RAI at a specialized oncology PICU.

METHODS

Retrospective cohort study involving two pediatric intensive care units located within a general hospital and an oncology hospital. Children aged ≥ 3 months to < 18 years admitted to the intensive care units in 2017 with a length of stay ≥ 72 h were included.

RESULTS

The sample included 249 patients, of which 51% were male (127 patients), with median age of 77 months, and mean ICU stay of 5 days. Of the total admissions, 141 were clinical (57%) and 108 surgical. The rate of AKI was 15% and death rate within 30 days was 13%. Having a positive RAI on admission showed a statistically significant association with AKI at Day 3 (OR = 18.5, 95%CI = 4.3 - 78.9, p < 0.001) and with death (OR = 3.9, 95%CI = 1.6 - 9.9, p = 0.004). The accuracy of the RAI in the cancer population was 0.81 on the ROC curve (95%CI 0.74, 0.88).

CONCLUSIONS

The RAI is a useful tool for predicting AKI and death in critically ill children, including in oncology units.

Optimization of Ganciclovir and Valganciclovir Starting Dose in Children by Machine Learning

BACKGROUND AND OBJECTIVES

Ganciclovir (GCV) and valganciclovir (VGCV) show large interindividual pharmacokinetic variability, particularly in children. The objectives of this study were (1) to develop machine learning (ML) algorithms trained on simulated pharmacokinetics profiles obtained by Monte Carlo simulations to estimate the best ganciclovir or valganciclovir starting dose in children and (2) to compare its performances on real-world profiles to previously published equation derived from literature population pharmacokinetic (POPPK) models achieving about 20% of profiles within the target.

MATERIALS AND METHODS

The pharmacokinetic parameters of four literature POPPK models in addition to the World Health Organization (WHO) growth curve for children were used in the mrgsolve R package to simulate 10,800 pharmacokinetic profiles. ML algorithms were developed and benchmarked to predict the probability to reach the steady-state, area-under-the-curve target (AUC0-24 within 40-60 mg × h/L) based on demographic characteristics only. The best ML algorithm was then used to calculate the starting dose maximizing the target attainment. Performances were evaluated for ML and literature formula in a test set and in an external set of 32 and 31 actual patients (GCV and VGCV, respectively).

RESULTS

A combination of Xgboost, neural network, and random forest algorithms yielded the best performances and highest target attainment in the test set (36.8% for GCV and 35.3% for the VGCV). In actual patients, the best GCV ML starting dose yielded the highest target attainment rate (25.8%) and performed equally for VGCV with the Franck model formula (35.3% for both).

CONCLUSION

The ML algorithms exhibit good performances in comparison with previously validated models and should be evaluated prospectively.

Impact of the first 24 h of continuous kidney replacement therapy on hemodynamics, ventilation, and analgo-sedation in critically ill children

BACKGROUND

In a group of children admitted to the paediatric intensive care unit (PICU) receiving continuous kidney replacement therapy (CKRT), we aim to evaluate the data about their hemodynamic, ventilation and analgo-sedation profile in the first 24 h of treatment and possible associations with mortality.

METHODS

Retrospective cohort study of children admitted to the PICU of the University Hospital of Padova undergoing CKRT between January 2011 and March 2021. Data was collected at baseline (T0), after 1 h (T1) and 24 h (T24) of CKRT treatment. The differences in outcome measures were compared between these time points, and between survivors and non-survivors.

RESULTS

Sixty-nine patients received CKRT, of whom 38 (55%) died during the PICU stay. Overall, the vasoactive inotropic score and the adrenaline dose increased at T1 compared to T0 (p = 0.012 and p = 0.022, respectively). Compared to T0, at T24 patients showed an improvement in the following ventilatory parameters: Oxygenation Index (p = 0.005), Oxygenation Saturation Index (p = 0.013) PaO2/FiO2 ratio (p = 0.005), SpO2/FiO2 ratio (p = 0.002) and Mean Airway Pressure (p = 0.016). These improvements remained significant in survivors (p = 0.01, p = 0.027, p = 0.01 and p = 0.015, respectively) but not in non-survivors. No changes in analgo-sedative drugs have been described.

CONCLUSIONS

CKRT showed a significant impact on hemodynamics and ventilation in the first 24 h of treatment. We observed a significant rise in the inotropic/vasoactive support required after 1 h of treatment in the overall population, and an improvement in the ventilation parameters at 24 h only in survivors.

Editorial on the Special Issue "Advances in Pediatric Acute Kidney Injury"

Acute kidney injury (AKI) refers to a swift decline in kidney function, marked by the reduced excretion of waste products and disturbances in fluid and electrolyte balance [...].

Latamoxef dosing regimen adjustments and pharmaceutical care in pediatrics

Latamoxef is a semi-synthetic, broad-spectrum oxacephem antibiotic used primarily to treat infectious diseases, but the adverse drug reactions, such as the risk of fatal bleeding, once caused physicians to use it less frequently. However, with the rise of antibiotic-resistant bacterial strains, latamoxef is being used again to treat infectious diseases, especially in pediatrics. The pharmacokinetic parameters of latamoxef are highly variable, given the changes in body composition, organ maturation, and development that occurs in pediatrics. Therefore, an appropriate dosing regimen is essential. Latamoxef dosing optimization in pediatrics should adequately account for current body weight, postnatal age, postmenstrual age, and different minimum inhibitory concentration (MIC) values. In addition, attention should also be paid to some of the adverse reactions associated with latamoxef, such as coagulation disorders and bleeding risks, disulfiram-like reactions, as well as hypersensitivity and anaphylactic shock. This review summarizes the dosing regimens and some key points of pharmaceutical care for latamoxef in pediatrics in order to provide a better reference for its application in clinical practice.

Outcomes of children with isolated antenatal hydronephrosis

BACKGROUND

Antenatal hydronephrosis (ANH) is one of the most common abnormalities detected during prenatal ultrasound. There is significant variability in the postnatal management of ANH. Our objective was to report the outcomes of patients with ANH, spontaneous resolution rates, surgical intervention rates, and factors contributing to these parameters.

METHODS

A total of 227 patients and 264 renal units with ANH were included in this study. We used the renal pelvis anteroposterior diameter and the Society for Fetal Urology grading system to classify and compare ANH as mild, moderate, and severe.

RESULTS

The patients' median follow-up period was 48 months (with a minimum of 6 months and a maximum of 136 months). Of the 264 renal units, 123 (46.6%) had mild, 101 (38.26%) had moderate, and 40 (15.15%) had severe antenatal hydronephrosis. The spontaneous resolution rate was 91.9% in the mild hydronephrosis group (n = 113), 81.2% (n = 82) in the moderate hydronephrosis group, and 37.5% (n = 15) in the severe hydronephrosis group. The patients with higher hydronephrosis grades required a longer time to resolve. Only one patient with a posterior urethral valve had reduced estimated glomerular filtration. None of the patients had proteinuria or hypertension.

CONCLUSION

Although the outcome of the patients with mild hydronephrosis was excellent, there was a progression of the disease, especially within the first 6 months, and 6% of our cases required surgical intervention. Additional prospective studies are needed to define the risk of urinary tract abnormalities with any degree of ANH.

Malnutrition and protein energy wasting are associated with severity and progression of pediatric chronic kidney disease

BACKGROUND

Protein energy wasting (PEW), a state of deficient protein storage, is not well understood in children and adolescents with chronic kidney disease (CKD). We aimed to re-define PEW using pediatric malnutrition guidelines from the Academy of Nutrition and Dietetics/American Society for Parenteral and Enteral Nutrition (AND/ASPEN), and to describe the relationship between PEW, malnutrition, and kidney function.

METHODS

This was a retrospective review of outpatients ≤ 20 years old with a diagnosis of CKD from January 1, 2013, to August 31, 2018. Malnutrition was diagnosed by a licensed dietitian, and PEW was diagnosed using an updated definition incorporating AND/ASPEN malnutrition guidelines. Logistic regression and linear mixed effects modeling were performed on the relationship of malnutrition and PEW to estimated glomerular filtration rate (eGFR).

RESULTS

The 142 patients included in this analysis had a median age of 11.1 years and median eGFR of 57 ml/min/1.73 m2 at initial visit. Malnutrition was diagnosed in 50% of patients in at least one visit, and 17.6% met ≥ 2 PEW criteria. Patients with eGFR < 30 ml/min/1.73 m2 had significantly increased risk of malnutrition [OR 2.5, 95% CI 2.0-3.3] (p < 0.001) and PEW [OR 4.9, 95% CI 3.0-8.0] (p < 0.001). A diagnosis of malnutrition or PEW was associated with worse eGFR by logistic regression (p = 0.01 and p = 0.001, respectively) and more rapid eGFR decline by linear mixed effects model (p = 0.002 and p < 0.001, respectively) compared to those without these diagnoses.

CONCLUSIONS

Malnutrition and PEW are prevalent in pediatric CKD and are associated with significantly lower eGFR and more rapid decline in eGFR, emphasizing the need to address nutritional status. A higher resolution version of the Graphical abstract is available as Supplementary information.

The Importance of Sphingomyelin Phosphodiesterase Acid-Like 3b (SMPDL-3b) Levels in Kidney Biopsy Specimens of Children With Nephrotic Syndrome

OBJECTIVE

It remains unclear whether the low amount of SMPDL-3b required for rituximab binding is the cause of treatment resistance in patients with treatment-resistant nephrotic syndrome with advanced podocyte injury. Given the limited number of studies on the relationship between rituximab and SMPDL-3b, this study was conducted to assess whether SMPDL-3b levels in pretreatment renal biopsy specimens can be used to predict the clinical effectiveness of immunosuppressive drugs, especially rituximab, in children with nephrotic syndrome.

METHODS

Kidney biopsy specimens from 44 patients diagnosed with idiopatic nephrotic syndrome were analyzed using immunohistochemical staining with an anti-SMPDL-3b antibody and real-time polymerase chain reaction (PCR) for SMPDL-3b mRNA expression.

RESULTS

We showed that SMPDL-3b mRNA expression and anti-SMPDL-3b antibody staining did not differ significantly between the patient groups with different responses to immunosuppressive therapies.

CONCLUSION

Our results suggest that SMPDL-3b may actually be an indicator of disease progression rather than a marker for predicting response to a particular immunosuppressive agent.

Profile of plasma free amino acids, carnitine and acylcarnitines, and JAK2v617f mutation as potential metabolic markers in children with type 1 diabetic nephropathy

Fifty diabetic nephropathy (DN) children with type 1 diabetes mellitus (T1DM) and 50 healthy matched controls were included. Chromatographic assays of 14 amino acids, free carnitine and 27 carnitine esters using high-performance liquid chromatography/electrospray ionization-mass spectroscopy, and genetic testing for JAK2v617f mutation using real-time PCR were performed. Patients had significantly lower levels of tyrosine, branched-chain amino acids (BCAAs), and BCAA/AAA (aromatic chain amino acids) ratios, glycine, arginine, ornithine, free carnitine and some carnitine esters (C5, 6, 12 and 16) and higher phenylalanine, phenylalanine/tyrosine ratio and C18 compared with the controls and in the macro-albuminuria vs. the microalbuminuria group (p < 0.05 for all) except for free carnitine. Plasma carnitine was negatively correlated with eGFR (r = -0.488, p = 0.000). There were significant positive correlations between tyrosine with UACR ratio (r = 0.296, p = 0.037). The plasma BCAA/AAA ratio showed significant negative correlations with UACR (r = -0.484, p = 0.000). There was a significantly higher frequency of the JAK2V617F gene mutation in diabetic nephropathy patients compared with the control group and in macro-albuminuria than the microalbuminuria group (p = 0.000) for both. When monitoring children with T1DM, plasma free amino acids and acylcarnitine profiles should be considered, especially if they have tested positive for JAK2V617F for the early diagnosis of DN.

Physiologically-Based Pharmacokinetic Modeling for Drug Dosing in Pediatric Patients: A Tutorial for a Pragmatic Approach in Clinical Care

It is well-accepted that off-label drug dosing recommendations for pediatric patients should be based on the best available evidence. However, the available traditional evidence is often low. To bridge this gap, physiologically-based pharmacokinetic (PBPK) modeling is a scientifically well-founded tool that can be used to enable model-informed dosing (MID) recommendations in children in clinical practice. In this tutorial, we provide a pragmatic, PBPK-based pediatric modeling workflow. For this approach to be successfully implemented in pediatric clinical practice, a thorough understanding of the model assumptions and limitations is required. More importantly, careful evaluation of an MID approach within the context of overall benefits and the potential risks is crucial. The tutorial is aimed to help modelers, researchers, and clinicians, to effectively use PBPK simulations to support pediatric drug dosing.

Levetiracetam pharmacokinetics and its covariates: proposal for optimal dosing in the paediatric population

OBJECTIVES

Levetiracetam is an anticonvulsive drug increasingly used in paediatric populations. Ontogenesis may alter its pharmacokinetics, demanding dose individualisation of levetiracetam in paediatric populations. We therefore aimed to explore levetiracetam pharmacokinetics and to propose its optimal dosing in the paediatric population.

METHODS

Individual levetiracetam pharmacokinetic parameters were calculated based on therapeutic drug monitoring data, using a one-compartmental model, and regression models were used to explore possible covariates.

RESULTS

56 patients aged from 47 days to 18 years were included in the analysis. The median (IQR) volume of distribution and clearance of levetiracetam were 0.7 (0.58-0.85) L/kg and 0.123 (0.085-0.167) L/hour/kg, respectively. Levetiracetam pharmacokinetics were influenced by postnatal age, body size descriptors and renal functional status.

CONCLUSIONS

Based on observed relationships, an individualised loading dose of 26.2 mg/kg body weight and maintenance dose of 20.7 mg/mL/min of estimated glomerular filtration rate were calculated as optimal. Since we observed increased levetiracetam clearance in association with valproate co-medication, caution should be used when combining these two drugs.

Long-term kidney follow-up after pediatric acute kidney support therapy for children less than 15 kg

BACKGROUND

In small children, acute dialysis (pediatric acute kidney support therapy (paKST)) is increasingly used; however, it is challenging for many reasons. We compared clinical characteristics and predictors of long-term outcomes of patients < 15 kg on peritoneal dialysis (PD), hemodialysis (HD), and continuous kidney replacement therapy (CKRT).

METHODS

Patients with history of paKST (CKRT, HD, PD) weighing < 15 kg and ≥ 6 months of follow-up at Hacettepe University were included. Surviving patients were evaluated at last visit.

RESULTS

109 patients (57 females) were included. Median age at paKST was 10.1 months (IQR: 2-27 months). In total, 43 (39.4%) patients received HD, 37 (34%) PD, and 29 (26.6%) CKRT. 64 (58.7%) patients died a median 3 days (IQR: 2-9.5 days) after paKST. Percentages of patients using vasopressor agents, with sepsis, and undergoing mechanical ventilation were lower in those who survived. After mean follow-up of 2.9 ± 2.1 years, 34 patients were evaluated at mean age 4.7 ± 2.4 years. Median spot urine protein/creatinine was 0.19 (IQR: 0.13-0.37) and 12 patients (35.3%) had non-nephrotic proteinuria. Three patients had estimated glomerular filtration rate (eGFR) < 90 mL/min/1.73m2 and 2 (6%) had hyperfiltration. In total 22 patients (64.7%) had ≥ 1 kidney risk factor (elevated blood pressure/hypertension, hyperfiltration, eGFR < 90 ml/min/1.73m2, and/or proteinuria) at last visit. Among 28 patients on paKST < 32 months, 21 had ≥ 1 risk factor (75%), whereas among 6 patients who had paKST ≥ 32 months, one patient had ≥ 1 risk factor (16.7%), (p = 0.014).

CONCLUSIONS

Patients on paKST who undergo mechanical ventilation and vasopressor treatment should be followed-up more closely. After surviving the acute period, patients on paKST need to be followed-up closely during the chronic stage. A higher resolution version of the Graphical abstract is available as Supplementary information.

The Clinical Profile and Long-Term Outcome of Children with Membranous Nephropathy, and the Evaluation of Anti-Phospholipase A2 Receptor Antibody Immunohistochemistry in Kidney Biopsy

Introduction

Idiopathic membranous nephropathy (iMN) is a rare cause of nephrotic syndrome in children (1%-7%). Anti-phospholipase A2 receptor (PLA2R) antibody positivity in kidney biopsy is observed in 52%-78% of adults and 45% of children with iMN. The objectives of the study are to analyze the clinical profile and outcome of membranous nephropathy in children, to assess the prevalence of anti-PLA2R immunohistochemistry (IHC) in kidney biopsy, and to correlate their presence with disease characteristics.

Methods

We are reporting a single-center retrospective study conducted in pediatric nephrology division. Clinical data and outcome parameters of children with membranous nephropathy were analyzed. PLA2R IHC was performed in kidney biopsy specimens retrospectively.

Results

We analyzed 43 children with membranous nephropathy (MN) from a single center. 18 (42%) had idiopathic MN (iMN). PLA2R IHC was performed in kidney biopsy specimens in 14/18 (78%) patients with iMN and 7/9 (78%) non-lupus secondary membranous nephropathy (SMN) patients. The most common cause of SMN was lupus nephritis in 16 patients (64%). The mean estimated glomerular filtration rate (eGFR) at onset was 156 ± 81 ml/min/1.73m2. The sensitivity and specificity of PLA2R IHC in diagnosing pediatric MN was 50% and 57%, respectively; positive and negative predictive values were 70% and 36%, respectively. At the final follow-up, chronic kidney disease stage 5 (CKD 5) developed in 2/14 (14.3%) iMN patients.

Conclusions

IHC PLA2R staining of glomerular tissue is a useful diagnostic marker of IMN. Though PLA2R prevalence is lower in children, its role in guiding treatment needs further exploration.

Clinical Review of Risk of Nephrotoxicity with Acyclovir Use for Treatment of Herpes Simplex Virus Infections in Neonates and Children

OBJECTIVE

This study aims to clarify the risk of nephrotoxicity with intravenous use of acyclovir (ACV) for the treatment of neonates (ages <3 months) and children (ages ≥3 months to <12 years) with herpes simplex virus (HSV) infections and to identify gaps in knowledge that could be further investigated.

METHODS

Multiple databases were searched to identify studies on risk of nephrotoxicity with ACV use for treatment of invasive HSV infections, defined as any neonatal infection or HSV encephalitis (HSE) in children.

RESULTS

There were 5 and 14 studies that evaluated the risk of ACV-associated nephrotoxicity in neonates and children, respectively. The US Food and Drug Administration (FDA) delayed the approval of high (HD; 60 mg/kg/day) ACV in neonates secondary to risk of toxicity. Based on our review, the risk of ACV-associated nephrotoxicity was lower in the neonatal compared with the pediatric population. Acyclovir dose >1500 mg/m2, older age, and concomitant use of nephrotoxic drugs were identified as variables that increased the risk of ACV nephrotoxicity in children. Although the FDA has approved the use of HD ACV for the treatment of HSE in children, the American Academy of Pediatrics recommends a lower dose to minimize the risk of toxicity. The efficacy and safety of high vs lower doses of ACV for the management of HSE in children has yet to be evaluated.

CONCLUSIONS

The risk of ACV-associated nephrotoxicity was lower among neonates compared with older children. Future studies are needed to identify the optimal dosage that minimizes toxicities and maximizes the efficacy of ACV in children with HSE.

Dietary acid load in children with chronic kidney disease: its association with nutritional status and health-related quality of life

BACKGROUND

This study aimed to determine the dietary acid load of children with chronic kidney disease (CKD) and to evaluate the relationship between dietary acid load, nutritional status, and health-related quality of life (HRQOL).

METHOD

A total of 67 children aged 3-18 years with a diagnosis of CKD stages II-V were included in the study. Anthropometric measurements (body weight, height, mid-upper arm circumference, waist, and neck circumference) and 3-day food consumption records were taken to evaluate the nutritional status. The net endogenous acid production (NEAP) score was calculated to determine the dietary acid load. "Pediatric Inventory of Quality of Life (PedsQL)" was used to assess the participants' HRQOL.

RESULTS

The mean NEAP was 59.2 ± 18.96 mEq/day. Stunted and malnourished children had significantly higher NEAP than those who were not (p < 0.05). There were no significant differences in terms of HRQOL scores according to NEAP groups. The multivariate logistic regression analysis showed that waist circumference (OR: 0.890, 95% CI: 0.794-0.997), serum albumin (OR: 0.252, 95% CI: 0.068-0.929), and glomerular filtration rate (GFR) (OR: 0.985, 95% CI: 0.970-1.000) were negatively associated with high NEAP.

CONCLUSION

This study shows that a diet shifted in an acidic direction in children with CKD and a higher dietary acid load are associated with lower serum albumin, GFR, and waist circumference, but not HRQOL. These results suggest that dietary acid load might affect nutritional status and CKD progression in children with CKD. Future studies with larger samples are needed to confirm these results and to understand underlying mechanisms. A higher resolution version of the Graphical abstract is available as Supplementary information.

Immunosuppressive Therapy of Antibody-Mediated aHUS and TTP

The recent classification of pediatric thrombotic microangiopathies (TMA) takes into consideration mechanisms of disease for guidance to targeted therapies. We present our experience with seven patients with antibody mediated atypical hemolytic uremic syndrome (aHUS) and thrombotic thrombocytopenic purpura (TTP). Five children had aHUS with antibodies against complement factor H (CFH-ab) and two with TTP with antibodies against metalloproteinase ADAMTS13. In the aHUS cases diagnosed and treated before the eculizumab era, CFH-ab was detected using the ELISA assay. Mutational analysis of selected complement genes was performed. TTP was diagnosed if, in addition to microangiopathic hemolytic anemia and thrombocytopenia, ischemic organ involvement and severe deficiency in ADAMTS13 activity were present. Treatment protocol consisted of plasma exchanges (PE) and steroid pulses, followed by the combination of cyclophosphamide and rituximab to achieve long-term immunosuppression. Four patients with CFH-ab and the TTP patients with ADAMTS13 antibodies came into sustained remission. After a median follow-up of 11.7 (range 7.7-12.9) years without maintenance therapy, no disease recurrence was observed; nevertheless, six patients, two had hypertension and two had proteinuria as a late consequence. One patient, with late diagnosis of CFH-ab and additional genetic risk factors who was treated only with PE and plasma substitution, reached end-stage renal disease and was later successfully transplanted using eculizumab prophylaxis. In the cases of antibody-mediated TMAs, PE and early immunosuppressive treatment may result in sustained remission with preserved kidney function. Further data are needed to establish optimal treatment of anti-FH antibody-associated HUS.