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

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.

CCL22 and Leptin associated with steroid resistance in childhood idiopathic nephrotic syndrome

Objective

Previous studies have indicated a decrease in T regulatory cells (Tregs) among patients with steroid-resistant nephrotic syndrome. CCL22 and Leptin influenced the immune function of Tregs through their respective pathways. This study aimed to compare patients with steroid-sensitive nephrotic syndrome (SSNS) and steroid-resistant nephrotic syndrome (SRNS) in terms of CCL22 and Leptin levels.

Methods

This prospective study included 117 children diagnosed with idiopathic nephrotic syndrome (INS). Peripheral blood samples were collected before initiating steroid therapy, and serum levels of CCL22 and Leptin were measured. Patients were categorized into three groups based on their response to steroid treatment. Renal biopsies were recommended for all children diagnosed with INS, with higher acceptance rates in glucocorticoid resistance patients.

Results

Based on the response to steroid treatment, 117 children were divided as groups of SSNS (82 cases), frequent relapse nephrotic syndrome (FRNS) (10 cases), and SRNS (25 cases). A total of 41 patients underwent kidney biopsy, 11 cases (13.4%) in SSNS, 7 cases (70.0%) in FRNS and 24 cases (96.0%) in SRNS. 30 cases were minimal change disease (MCD), 9 cases were mesangial proliferative glomerulonephritis (MsPGN) and 3 cases were focal segmental glomerulosclerosis (FSGS). The levels of Leptin were significantly higher in SR patients (1208.1 ± 1044.1 pg/ml) compared to SS patients (515.4 ± 676.9 pg/ml) and controls (507.9 ± 479.8 pg/ml), regardless of the pathological type. CCL22 levels were significantly elevated in SRNS (92.2 ± 157.0 pg/ml), but the difference seemed to be attributed to the specific type of pathology, such as Minimal change disease (MCD) (127.4 ± 206.7 pg/ml) and focal segmental glomerulosclerosis (FSGS) (114.8 ± 22.0 pg/ml). For SRNS prediction, the AUC of Leptin, CCL22, and the joint prediction index were 0.764, 0.640, and 0.806, respectively.

Conclusion

Serum levels of CCL22 and Leptin, detected prior to steroid therapy, were associated with steroid resistance in childhood INS.

Clinical significance of hypouricemia in children and adolescents

BACKGROUND

Although hyperuricemia is a widely studied condition with well-known effects on the kidneys, hypouricemia is usually considered a biochemical abnormality of no clinical significance despite the fact that it can be a sign or major finding of serious metabolic or genetic diseases affecting kidney health. In this study, we aimed to investigate and emphasize the clinical significance of hypouricemia.

METHODS

Patients were evaluated retrospectively for persistent hypouricemia defined as serum uric acid concentrations of < 2 mg/dL on at least 3 different occasions. According to the blood and urine uric acid (UA) levels, the patients were classified as having hypouricemia due to UA underproduction vs. overexcretion. Demographic, clinical, and genetic characteristics were noted for analysis.

RESULTS

Fourteen patients (n = 14; M/F 8/6) with persistent hypouricemia were identified. Hypouricemia due to underproduction was the cause of 42.8% of these cases. All of the patients with a uric acid level of 0 mg/dL (n = 4) had hypouricemia due to underproduction. The median serum uric acid level was 0.85 (0-1.6) mg/dL. Isolated hypouricemia and hypouricemia with metabolic acidosis were equally distributed. Among the patients with hypouricemia due to underproduction, the final diagnoses were xanthine dehydrogenase deficiency (n = 5) and alkaptonuria (n = 1). In the overexcretion group, the final diagnoses were nephropathic cystinosis (n = 6), distal renal tubular acidosis (n = 1), and hereditary renal hypouricemia (n = 1). The diagnostic lag was longer for patients with isolated hypouricemia compared to other patients (p = 0.001).

CONCLUSIONS

Hypouricemia may reflect underlying genetic or metabolic diseases, early diagnosis of which could help preserve kidney function. A higher resolution version of the Graphical abstract is available as Supplementary information.

Association of antenatal corticosteroids with kidney function in adolescents born preterm with very low birth weight

OBJECTIVE

Investigate if antenatal corticosteroids (ANCS) are associated with worse kidney function in adolescence and if greater adiposity magnifies this association.

STUDY DESIGN

Prospective cohort of 162 14-year-olds born preterm with very low birth weight (<1500 g). Outcomes were estimated glomerular filtration rate (eGFR) and first-morning urine albumin-to-creatinine ratio (UACR). We used adjusted generalized linear models, stratified by waist-to-height ratio (WHR) ≥ 0.5.

RESULTS

Fifty-five percent had ANCS exposure and 31.3% had WHR ≥ 0.5. In adjusted analyses of the entire cohort, ANCS was not significantly associated with eGFR or UACR. However, the ANCS-eGFR association was greater in those with WHR ≥ 0.5 (β -16.8 ml/min/1.73 m2, 95% CL -31.5 to -2.1) vs. WHR < 0.5: (β 13.9 ml/min/1.73 m2, 95% CL -0.4 to 28.1), interaction term p = 0.02.

CONCLUSION

ANCS exposure was not associated with worse kidney function in adolescence, though ANCS may be associated with lower eGFR if children develop obesity by adolescence.

Serum IgE levels are a risk factor with prognosis of pediatric minimal change disease

BACKGROUND

Minimal change disease (MCD) is one of the most common primary glomerular disorders with high serum IgE levels. This study was aimed to investigate the clinical features of different serum IgE levels in pediatric MCD and evaluate the prognostic significance of serum IgE levels with regard to remission and relapse in pediatric cohort.

METHODS

This study enrolled 142 new-onset children diagnosed with biopsy-proven MCD from January 2010 to December 2021 at the Jinling Hospital in Nanjing, China. These cases were divided into three groups according to serum IgE levels. MCD patients' demographics, clinical parameters, and follow-up data were collected and analyzed. The primary and secondary outcomes were defined as the time to the first complete remission (CR) and the first relapse.

RESULTS

The results manifested that 85.2% (121/142) of MCD children had high serum IgE levels (IgE > 90.0 IU/ml). A total of 142 patients were divided into the normal-, low-, and high-IgE groups based on the normal reference value level (90.0 IU/ml) and median serum IgE level (597.5 IU/ml). The high-IgE group had a significantly lower cumulative rate of the first CR (log-rank, P = 0.032) and a higher rate of the first relapse (log-rank, P = 0.033) than the normal-IgE and low-IgE groups. Multivariate Cox analysis showed that IgE ≥597.5 IU/ml was independently associated with the delayed first CR [hazard ratio (HR) = 0.566, 95% confidence interval (CI) = 0.330-0.972, P = 0.039] and the early first relapse (HR = 2.767, 95% CI = 1.150-6.660, P = 0.023).

CONCLUSIONS

Serum IgE levels were an independent correlation factor for pediatric MCD-delayed remissions and early relapses.

A clinicopathological and prognostic study of 18 children with C1q nephropathy and focal segmental glomerulosclerosis: an 18-year experience from a single center

BACKGROUND

C1q nephropathy is a relatively rare glomerulonephritis characterized by dominant mesangial deposition of C1q. Even though C1q nephropathy has been described for more than three decades, the clinicopathological features and renal outcomes remain unclear. C1q nephropathy may present diverse morphological patterns, including focal segmental glomerulosclerosis and, the notion of C1q nephropathy as a separate disease entity is still debated. This study aimed to describe the clinical and prognostic relevance of C1q nephropathy in children with primary focal segmental glomerulosclerosis.

METHODS

Three hundred eighty-nine children were diagnosed with primary focal segmental glomerulosclerosis in Jinling Hospital from 2003 to 2020. Among them, 18 cases fulfilled the criteria for C1q nephropathy. We then selected as a control group 18 children with primary focal segmental glomerulosclerosis without C1q nephropathy matched to those with C1q nephropathy for age, sex, and period of renal biopsy. Clinical and prognostic parameters were compared in children with and without C1q nephropathy. Renal end-point was defined as a ≥ 40% reduction in estimated glomerular filtration rate or end-stage renal disease.

RESULTS

Four point sixty-three percent (18/389) of primary focal segmental glomerulosclerosis cases were diagnosed with C1q nephropathy. The male-to-female ratio of patients diagnosed with C1q nephropathy was 1:1. The median age at biopsy and age at onset was 15.63 (13.00-16.50) years and 14.50 (9.00-16.00) years, respectively. The prevalence of nephrotic syndrome, hematuria, and hypertension was 38.90% (7/18), 72.20% (13/18), and 33.30% (5/18), respectively. Four (22.2%) patients were steroid-dependent, 13 (72.2%) patients were steroid-resistant, and 1 (5.6%) patient developed secondary steroid-resistance. During a follow-up of 52.24 (25.00-72.47) months, 10 (55.6%) patients achieved remission, and 5 (27.8%) progressed to the end-point [including 2 (11.11%) patients who developed end-stage kidney disease]. There was no significant difference in the estimated end-stage renal disease-free survival rates, the estimated end-point-free survival rates, and the long-term remission rate between patients with and without C1q nephropathy (Kaplan-Meier, Log-rank, all P > 0.05).

CONCLUSIONS

C1q nephropathy was rare in pediatric patients with focal segmental glomerulosclerosis. These patients usually had poor response to steroids. The long-term renal outcomes and remission of children with primary focal segmental glomerulosclerosis with C1q nephropathy were comparable to those without C1q nephropathy.

A different approach to cystinosis: ultrasound, doppler, and shear wave elastography findings of thyroid gland

BACKGROUND

While thyroid dysfunction develops in about 50% of untreated children with cystinosis, there is no data about how the sonography of thyroid tissue appears in this disease. Therefore, the purpose of this study was to assess the sonographic appearance, color doppler findings in this disease and to evaluate how cystine crystal accumulation affect tissue stiffness using shear wave elastography (SWE).

METHODS

Sixteen children diagnosed with cystinosis and a control group consisting of 34 healthy children were included in this study. B mode ultrasound, color doppler imaging and real-time SWE of thyroid tissue were performed.

RESULTS

Ultrasound imaging revealed lower echogenicity and diffuse heterogeneous echotexture in 7 of the 16 cystinosis patients. Thyroid gland volumes were lower in cystinosis patients (p 0.005). Doppler ultrasound demonstrated increased flow in 8 patients. On SWE, the thyroid tissue stiffness was established to be lower in patients compared to healthy children (p 0.003).

CONCLUSIONS

This is the first study evaluating thyroid gland B mode, color doppler ultrasonography, and SWE findings in cystinosis. Our findings indicate that cysteamine treatment still cannot completely prevent the disease infiltration process of thyroid gland. The other important finding-that thyroid tissue stiffness was established to be lower than that of the controls-also demonstrates the ongoing disease infiltration process.

Retroperitoneal kidney transplantation with liver and native kidney mobilization: a safe technique for pediatric recipients

BACKGROUND

Pediatric kidney transplant (KT) using larger, deceased or living donor adult kidneys can be challenging in the pediatric population due to limited space in the retroperitoneum. Liver and native kidney (L/NK) mobilization techniques can be used in smaller and younger transplant recipients to aid in retroperitoneal placement of the renal allograft. Here, we compare the clinical outcomes of pediatric retroperitoneal KT with and without L/NK mobilization.

METHODS

We retrospectively analyzed pediatric renal transplant recipients treated between January 2015 and May 2021. Donor and recipient demographics, intraoperative data, and recipient outcomes were included. Recipients were divided into two groups according to the surgical technique utilized: with L/NK mobilization (Group 1) and without L/NK mobilization (Group 2). Baseline variables were described using frequency distributions for categorical variables and means and standard errors for continuous variables. Tests of association with the likelihood of using L/NK mobilization were performed using standard χ2 tests, t tests, and the log-rank test.

RESULTS

Forty-six pediatric recipients were evaluated and categorized into Group 1 (n = 26) and Group 2 (n = 20). Recipients in Group 1 were younger (6.7 ± 0.8 years vs. 15. 3 ± 0.7, P < 0.001), shorter (109.5 ± 3.7 vs. 154.2 ± 3.8 cm, P < 0.001) and weighed less (21.4 ± 2.0 vs. 48.6 ± 3.4 kg, P < 0.001) than those in Group 2. Other baseline characteristics did not differ between Groups 1 and 2. One urologic complication was encountered in Group 2; no vascular or surgical complications were observed in either group. Additionally, no stents or drains were used in any of the patients. There were no cases of delayed graft function or graft primary nonfunction. The median follow-up of the study was 24.6 months post-transplant. Two patients developed death-censored graft failure (both in Group 2, P = 0.22), and there was one death with a functioning graft (in Group 2, P = 0.21).

CONCLUSIONS

Retroperitoneal liver/kidney mobilization is a feasible and safe technique that facilitates implantation of adult kidney allografts into pediatric transplant recipients with no increased risk of developing post-operative complications, graft loss, or mortality.

Predictors of long-term outcomes in pediatric focal segmental glomerulosclerosis

BACKGROUND

Available data on primary focal segmental glomerulosclerosis (FSGS) in children usually report on short follow-up and small samples. Furthermore, the application of the Columbia classification for FSGS in children has not yet been fully agreed. We aimed to confirm the prognosis and risk factors of FSGS in a large cohort of Chinese children.

METHODS

Two hundred seventy-four children with primary FSGS from a single center were enrolled from 2003 to 2018. Long-term renal survival and related risk factors were evaluated by the Kaplan-Meier method and Cox multivariate regression analysis. Receiver operating characteristic (ROC) curve analysis further tested the effect of various risk factors in predicting renal outcomes. The composite end-point included ≥ 50% reduction in estimated glomerular filtration rate and/or end-stage renal disease or death.

RESULTS

One hundred twenty-five children were diagnosed with not otherwise specified (NOS) (45.6%) variant; 79 with tip lesions (28.8%), 32 with collapsing (11.7%), 31 with cellular (11.3%), and 7 with perihilar lesions (2.6%). The renal survival rate was 80.73% at 5 years, 62.58% at 10 years and 34.66% at 15 years. Multivariate analysis showed that chronic tubulointerstitial damage ≥ 25% (HR 4.14, 95% CI 1.49-11.50, P < 0.01), collapsing variant [(reference: NOS) HR 2.16, 95% CI 1.10-4.27, P = 0.03], segmental sclerosis (HR 1.03, 95% CI 1.01-1.04, P < 0.01) and age at biopsy (HR 0.91, 95% CI 0.85-0.98, P = 0.01) were significantly associated with renal outcomes. ROC curve analysis showed an excellent diagnostic yield of the Columbia classification. The combination of Columbia classification, CTI ≥ 25% and segmental sclerosis had the best predictive value for renal outcomes (AUC = 0.867, sensitivity = 77.78%, specificity = 82.27%, P < 0.01).

CONCLUSIONS

This study reports a renal survival rate of Chinese children with FSGS of 62.58% at 10 years and 34.66% at 15 years. Prognosis is poorer in patients with collapsing variant or CTI ≥ 25% and good in patients with tip variant. The Columbia classification is confirmed as a valuable tool for predicting prognosis of Chinese children with FSGS.

Potential of Urine Biomarkers CHI3L1, NGAL, TIMP-2, IGFBP7, and Combinations as Complementary Diagnostic Tools for Acute Kidney Injury after Pediatric Cardiac Surgery: A Prospective Cohort Study

Acute kidney injury (AKI) is common after pediatric cardiac surgery (CS). Several urine biomarkers have been validated to detect AKI earlier. The objective of this study was to evaluate urine CHI3L1, NGAL, TIMP-2, IGFBP7, and NephroCheck® as predictors for AKI ≥ 1 in pediatric CS after 48 h and AKI ≥ 2 after 12 h. Pediatric patients (age < 18 year; body weight ≥ 2 kg) requiring CS were prospectively included. Urine CHI3L1, NGAL, TIMP-2, IGFBP7, and NephroCheck® were measured during surgery and intensive care unit (ICU) stay and corrected for urine dilution. One hundred and one pediatric patients were included. AKI ≥ 1 within 48 h after ICU admission occurred in 62.4% and AKI ≥ 2 within 12 h in 30.7%. All damage biomarkers predicted AKI ≥ 1 within 48 h after ICU admission, when corrected for urine dilution: CHI3L1 (AUC-ROC: 0.642 (95% CI, 0.535–0.741)), NGAL (0.765 (0.664–0.848)), TIMP-2 (0.778 (0.662–0.868)), IGFBP7 (0.796 (0.682–0.883)), NephroCheck® (0.734 (0.614–0.832)). Similarly, AKI ≥ 2 within 12 h was predicted by all damage biomarkers when corrected for urine dilution: uCHI3L1 (AUC-ROC: 0.686 (95% CI, 0.580–0.780)), NGAL (0.714 (0.609–0.804)), TIMP-2 (0.830 (0.722–0.909)), IGFBP7 (0.834 (0.725–0.912)), NephroCheck® (0.774 (0.658–0.865)). After pediatric cardiac surgery, the damage biomarkers urine CHI3L1, NGAL, TIMP-2, IGFBP7, and NephroCheck® reliably predict AKI after correction for urine dilution.

Vitamin D Deficiency in Childhood Cancer Survivors: Results from Southern Thailand

There is limited information on vitamin D deficiency among childhood cancer survivors (CSS), especially in tropical countries. The aims of this study are to determine the prevalence and risk factors for vitamin D deficiency in CCSs. This study was conducted at the long-term follow-up clinic for CCSs at Prince of Songkla University, Songkhla, Thailand. All CCSs who were followed up between January 2021 and March 2022 were enrolled. Demographic data, dietary dairy intake, average weekly duration of outdoor activities, total 25-hydroxyvitamin D [25(OH)D] levels, parathyroid hormone levels, and blood chemistry were collected. A total of 206 CCSs with a mean age at follow-up of 10.8 ± 4.7 years were included. The prevalence of vitamin D deficiency was 35.9%. Female gender (odds ratio (OR): 2.11, 95% CI: 1.08-4.13), obesity (OR: 2.01, 95% CI: 1.00-4.04), lack of outdoor activities (OR: 4.14, 95% CI: 2.08-8.21), and lower dietary dairy intake (OR: 0.59, 95% CI: 0.44-0.80) were independent risk factors for vitamin D deficiency. Vitamin D deficiency was common in CCSs and associated with female gender, obesity, lack of outdoor activities, and lower dietary dairy intake. Regular 25(OH)D screening should be established in long-term care to identify those who require vitamin D supplements.

Exploring the Past to Inform the Future to Optimize the Pharmacokinetics of Vancomycin in Children With Severe Burn Injuries

Sepsis remains one of the leading causes of death among pediatric patients with burn injuries. Despite limited vancomycin pharmacokinetic (PK) information within this population, it is widely used to treat severe burn injuries. Those with severe burns are at risk of nephrotoxicity, with an incidence of acute kidney injury (AKI) over 50%. Delivering an effective vancomycin dose and avoiding unnecessary toxicity is essential for improved patient outcomes. This was a retrospective analysis of 115 children aged 0.2 months to 18 years with severe burns, >10% total body surface area. Vancomycin was given via intravenous infusion; blood samples were drawn between 6- and 12-hour postinfusion. A population pharmacokinetic model was developed using nonlinear mixed-effect modeling (Monolix, version 2016R1). A one-compartment model described a steady-state volume of distribution (V), dependent on weight. Vancomycin clearance (CL) was influenced by age and estimated creatinine clearance (CrCL). The study population's (median age = 4 years, median weight = 20 kg, median total body surface area (%TBSA) = 40%) median V and CL were calculated to be 1.25 L/kg (95% CI, 1.04-1.46) and 0.15 L/h/kg (95% CI, 0.126-0.165), respectively. The PK model was explicitly developed to characterize the impact of physiological changes in children under 18 years of age and the percentage of the burn surface area using limited data. The analysis determined that weight, age, and estimated CrCL were important covariates in predicting vancomycin PK with high variability in CL and V.

Association between microscopic hematuria and albuminuria in patients with chronic kidney disease caused by diabetes and hypertension: the Fukuoka Kidney disease Registry Study

BACKGROUND

The association between microscopic hematuria (MH) and albuminuria in patients with chronic kidney disease (CKD) caused by diabetes and hypertension remains unclear.

METHODS

The Fukuoka Kidney disease Registry Study is a Japanese multicenter prospective cohort study of 4476 patients with non-dialysis-dependent CKD. In this cohort, we conducted a cross-sectional study in 994 patients with diabetic nephropathy and hypertensive nephrosclerosis. Patients were divided into three groups according to erythrocyte count in urine sediment [T1: < 5/high power field (HPF); T2: 5-9/HPF; T3: ≥ 10/HPF]. Macroalbuminuria was defined as urinary albumin-creatinine ratio > 300 mg/g. Associations between the degree of MH (T1-T3) and the prevalence of macroalbuminuria were analyzed using logistic regression.

RESULTS

The prevalence of macroalbuminuria was 50.8%, 50.4%, and 67.4% in T1 (n = 725), T2 (n = 226), and T3 (n = 43), respectively. The multivariable-adjusted odds ratios for the presence of macroalbuminuria were 0.95 [95% confidence interval (CI) 0.65-1.39; P = 0.86] and 2.50 (95% CI 1.15-5.47; P = 0.022) for patients in T2 and T3, respectively, compared with patients in T1.

CONCLUSIONS

MH with erythrocytes ≥ 10/HPF was significantly associated with increased prevalence of macroalbuminuria in patients with non-dialysis-dependent CKD caused by diabetes and hypertension.

Urine Complement Factor Ba Is Associated with AKI in Critically Ill Children

Key Points

Complement activation, specifically factor B, is implicated in AKI pathogenesis in animal models. Urine Ba (an activation fragment of factor B) was significantly higher in critically ill children with stage 3 AKI and sepsis-AKI. If larger studies show similar association between urine Ba and AKI severity, clinical trials of factor B inhibition are warranted.

Background:

Critically ill children with AKI have high morbidity and mortality rates and lack treatment options. Complement activation is implicated in AKI pathogenesis, which could be treated with complement-targeted therapeutics. We assessed for an association between urine Ba, an activation fragment of the alternative complement pathway, and AKI in a large cohort of critically ill children.

Methods:

A biorepository of children requiring mechanical ventilation was leveraged. AKI was based on pediatric version of the RIFLE criteria—stage 1: 25% decreased eGFR or urine output (UOP) <0.5ml/kg per hour for 8 hours; stage 2: 50% decreased eGFR or UOP <0.5 ml/kg per hour for 16 hours; stage 3: 75% decreased eGFR or UOP <0.3ml/kg per hour for 24 hours or anuric for 12 hours. ELISAs were performed to quantitate urine Ba values. Log Ba was used in ANOVA with pairwise comparison by the Tukey method. Logistic regression was performed to test the association between urine Ba and AKI diagnosis.

Results:

Seventy-three patients were included, of which 56 had AKI: 26 (46%) stage 1, 16 (29%) stage 2, and 14 (25%) stage 3. Ba was significantly higher in patients with stage 3 AKI compared with all other stages. Ba was higher in sepsis-associated AKI compared with non–sepsis-associated AKI. Multivariate analysis included urine Ba, urine IL-18, urine NGAL, sepsis, and Pediatric Risk of Mortality Scores-II (an estimate of illness severity) and showed a significant association between urine Ba and AKI (odds ratio 1.57, 95% confidence interval, 1.13 to 2.20; P 0.007).

Conclusion:

Urine Ba is significantly increased in patients with AKI compared with patients without AKI. In patients with similar illness severity, a doubling of urine Ba level was associated with a 57% increase in AKI diagnosis of any stage. Further studies are needed to study complement inhibition in treatment or prevention of AKI in critically ill children.

Consistent methods for fat-free mass, creatinine clearance, and glomerular filtration rate to describe renal function from neonates to adults

Quantifying the effect of kidney disease on glomerular filtration rate (GFR) is important when describing variability in the clearance of drugs eliminated by the kidney. We aimed to develop a continuous model for renal function (RF) from prematurity to adulthood based on consistent models for fat-free mass (FFM), creatinine production rate (CPR), and GFR. A model for fractional FFM in premature neonates to adults was developed using pooled data from 4462 subjects and 2847 FFM observations. It was found that girls have an FFM higher than that predicted from adult women based on height, total body mass, and sex, and boys have an FFM lower than adult men until around the onset of puberty, when it approaches adult male values. Data from 108 subjects with measurements of serum creatinine (Scr) and GFR were used to construct a model for CPR. Creatinine clearance was predicted using a model for CPR (based on FFM, postmenstrual age, and sex) and Scr that avoids discontinuous predictions between neonates, children, and adults. Individual CPR may then be used with individual Scr to predict the estimated GFR (eGFR; eGFR = CPR/Scr). A previously published model for human GFR based on 1153 GFR observations in 923 subjects without known kidney disease was updated using the model for fractional FFM to predict individual size and age-consistent values for the expected normal GFR (nGFR). Individual renal function was then calculated using RF = eGFR/nGFR.

Proenkephalin A as a marker for glomerular filtration rate in critically ill children: validation against gold standard iohexol GFR measurements

OBJECTIVES

Accurate determination of glomerular filtration rate (GFR) is important. Several endogenous biomarkers exist for estimating GFR, yet, they have limited accuracy, especially in the paediatric population. Proenkephalin A 119-159 (PENK) is a novel and promising GFR marker, but its relation with age in children remains unknown. Also, the value of PENK has never been validated against measured GFR (mGFR) in children when compared to traditional GFR markers including serum creatinine (SCr), SCr-based estimated GFR (eGFR) and cystatin C (cysC).

METHODS

Critically ill children and term-born neonates were included in this single-centre, prospective study. Iohexol-based mGFR, SCr, and cysC were determined in each patient. eGFR was calculated using the bedside Schwartz equation, incorporating SCr and height. Spearman correlation coefficients were calculated to determine the correlation between mGFR and PENK, SCr, cysC and eGFR.

RESULTS

For 97 patients (56 children and 41 neonates), mGFR, SCr, cysC and PENK levels were available. PENK levels were higher in young children and decreased to adult PENK reference values around two years of age. PENK levels were highly correlated with mGFR (ρ=-0.88, p<0.001), and similar to mGFR-eGFR correlation (ρ=-0.87, p<0.001). For cysC and SCr the correlation with mGFR was lower (ρ=-0.77 and ρ=-0.46, respectively. Both p<0.001).

CONCLUSIONS

The correlation of PENK with mGFR was as good as SCr-based eGFR-mGFR correlation. To determine the added value of PENK in paediatric clinical care and prior to implementation, PENK reference values are needed and the development and validation of a paediatric PENK-based eGFR equation is necessary.

'Children Kidney Care Centers': Rationale, requirements and recommendations for best facilities and better future

Specialized centers are needed for nephrology and urology care of children. The justifications are the specialized nature of care needed and the growing incidence and prevalence. Children with chronic kidney disease (CKD) are at risk of morbidity, mortality, and decreased quality of life. Current pediatric practice structures are apparently poorly suited for the increasing demands of chronic disease in children. Kidney diseases account for around 8%-10% of total outpatients and 12% of admissions to the pediatric ward in hospitals. The major causes of pediatric CKD in registries are congenital anomalies of the kidney and urinary tract (around 50%), followed by inherited nephropathies and glomerulonephritis. The nephrologist's role is important for specialized investigations and treatment. Urologist's services are essential for the wide variety of conditions from birth to early adult age for complete cure and complementing medical management. Children have a right to treatments and to resources that are as sophisticated and advanced as those available to adults. Simple and sophisticated care for all children with ailments of the kidneys and related structures is important for ensuring 'health for all'. The availability of 'Child Kidney Care Centers' will go a long way in improving the lives of affected children.

Effects of Lockdown for COVID-19 Pandemic on Chronic Kidney Disease Progression in Children with Congenital Anomalies of the Kidney and Urinary Tract: A Retrospective Pilot Study

The coronavirus disease 2019 (COVID-19) pandemic changed adults and children's lifestyle. We focused our attention on children affected by chronic kidney disease (CKD) due to congenital abnormalities of kidney and urinary tract (CAKUT) and their behavior during the lockdown. Our aims were to evaluate the incidence of CKD progression within 6 months after the end of the first Italian lockdown and the factors associated to it. CKD progression was defined by the transition to higher CKD stage or by the drop in estimated glomerular filtration rate by a 25% or more for patients belonging to CKD stages 1 and 2. We retrospectively selected 21 children with CAKUT and CKD ≥ stage 1 observed within 3 months before and 6 months after the first Italian lockdown. We called them by phone and asked them about their lifestyle before and during lockdown focusing on physical activity, screen time, sweet/candies/sugar-sweetened beverages eaten/drunk and adherence to the Mediterranean diet (MD) (through KIDMED questionnaire). We calculated and analyzed the delta between the pre- and post- lockdown observation of all collected parameters (clinical and biochemical parameters and questionnaires scores). Analyzing the overall cohort, we found significantly increased mean BMI and mean screen time and significantly lower mean physical activity time in post- compared with pre-lockdown observations. Eleven out of twenty-one patients (52.4%) had a worsening of CKD. These patients presented higher delta of levels of uric acid and microalbuminuria and showed minor adherence to the MD and declared to have consumed more sweets or candies or sugar-sweetened beverages/week during the lockdown with a tendentially major increment of BMI compared with patients not presenting CKD progression. In conclusion, the lockdown for COVID-19 pandemic determined increase of BMI in all enrolled patients due to a "forced" negative lifestyle. About half of these patients presented CKD progression. This progression was associated to less adherence to the MD and major consumption of sweets or candies or sugar-sweetened beverages.

Burden and severity of deranged electrolytes and kidney function in children seen in a tertiary hospital in Kano, northern Nigeria

INTRODUCTION

Derangement in serum electrolytes and kidney function is often overlooked, especially in resource-constrained settings, and associated with increased risk of morbidity and mortality. This study aimed to describe the burden of derangements in serum electrolytes and kidney function in children presenting to a tertiary hospital in Nigeria.

METHODS

The laboratory records of all children who had serum electrolytes urea and creatinine ordered on their first presentation to hospital between January 1 and June 30, 2017 were retrospectively reviewed. Basic demographic data including admission status (inpatient or outpatient) were recordedandserum levels of sodium, potassium, chloride and bicarbonate were assessed for derangements usingnormal values from established reference ranges. Results of repeat samples were excluded. Kidney function was classified based on the serum creatinine relative to normal values for age and sex.

RESULTS

During the study period, 1909 children (60.3% male); median (IQR) age 42 (11.9) months had serum chemistry and 1248 (65.4%) were admitted. Results of their first samples were analyzed. Electrolyte derangements were present in 78.6% of the samples most commonly hyponatraemia (41.1%), low bicarbonate(37.2%), hypochloraemia (33.5%) and hypokalemia(18.9%). Azotaemia was found in 20.1% of the results. Elevated serum creatinine levels were found in 399 children (24.7%), 24.1% of those being in the severe category. Children aged 5 years and younger accounted for 76.4% of those with derangement in kidney function. One hundred and eight outpatients (17.8%) had deranged kidney function.

CONCLUSION

Deranged serum electrolytes and kidney function were common in this cohort.

Improved equations to estimate GFR in Chinese children with chronic kidney disease

BACKGROUND

There is currently no specific equation for estimating glomerular filtration rate (GFR) in Chinese children with chronic kidney disease (CKD). The commonly used equations are less robust than expected; we therefore sought to derive more appropriate equations for GFR estimation.

METHODS

A total of 751 Chinese children with CKD were divided into 2 groups, training group (n = 501) and validation group (n = 250). In the training group, a univariate linear regression model was used to calculate predictability of variables associated with GFR. Residuals were compared to determine multivariate predictability of GFR in the equation. Standard regression techniques for Gaussian data were used to determine coefficients of GFR-estimating equations after logarithmic transformation of measured GFR (iGFR), height/serum creatinine (height/Scr), cystatin C, blood urea nitrogen (BUN), and height. These were compared with other well-known equations using the validation group.

RESULTS

Median ^99mTc-DTPA GFR was 90.1 (interquartile range: 67.3-108.6) mL/min/1.73 m² in training dataset. Our CKD equation, eGFR (mL/min/1.73 m²) = 91.021 [height(m)/Scr(mg/dL)/2.7]^0.443 [1.2/Cystatin C(mg/L)]^0.335 [13.7/BUN (mg/dL)]^-0.095 [ 0.991^male] [height(m)/1.4]^0.275, was derived. This was further tested in the validation group, with percentages of eGFR values within 30% and 15% of iGFR (P30 and P15) of 76.00% and 48.40%, respectively. For centres with no access to cystatin C, a creatinine-based equation, eGFR (mL/min/1.73 m²) = 89.674 [height(m)/Scr(mg/dL)/2.7]^0.579 [ 1.007^male] [height(m)/1.4]^0.187, was derived, with P30 and P15 73.60% and 49.20%, respectively. These were significantly higher compared to other well-known equations (p < 0.05).

CONCLUSION

We developed equations for GFR estimation in Chinese children with CKD based on Scr, BUN and cystatin C. These are more accurate than commonly used equations in this population.

Immature granulocytes as biomarkers of inflammation in children with predialysis chronic kidney disease

BACKGROUND

Chronic inflammation in patients with predialysis chronic kidney disease (CKD) is quite common. We aimed to investigate the relationship of the percentage of immature granulocytes (IG%) and immature granulocyte count (IGC) with inflammation in children with predialysis CKD.

METHODS

The data from children with stage 2-4 CKD and a control group of healthy children were evaluated retrospectively. A highly-sensitive C-reactive protein (hs-CRP) level above 5 mg/dL was considered the presence of inflammation. The IGCs were calculated in the white cell differential channel of the Sysmex XN-9000 using the fluorescent flow cytometry method. The IG% was expressed as percentage of total leucocyte concentration.

RESULTS

The data from 57 patients (30 stage 2 CKD, 15 stage 3 CKD, 12 stage 4 CKD) and 46 controls were analyzed. hs-CRP levels, IG%, IGC, white blood cell (WBC) and neutrophil counts, and neutrophil-to-lymphocyte ratio (NLR) were higher in patients than the control group (p < 0.000, p < 0.000, p < 0.000, p = 0.001, p = 0.002, p < 0.000, respectively). Both IG% and IGC were positively correlated with hs-CRP, WBC and neutrophil counts, and NLR (r = 0.485, p < 0.000; r = 0.379, p = 0.004; r = 0.543, p < 0.000; r = 0.628, p < 0.000 for IG%; r = 0.379, p = 0.004; r = 0.351, p = 0.007; r = 0.525, p < 0.000; r = 0.601, p < 0.000 for IGC, respectively). A ROC analysis of the relationship between IGC, IG%, and inflammation showed IGC and IG% had predictive value for the presence of inflammation (cut-off value: 0.035 × 10⁶/mL, AUC: 0.799 ± 0.061, sensitivity: 74.2%, specifity: 63%, p < 0.001 for IGC; cut-off value: 0.45%, AUC: 0.838 ± 0.056, sensitivity: 70.8%, specifity: 67.3%, p = 0.001 for IG%).

CONCLUSIONS

Immature granulocytes may be used as a biomarker of inflammation in children with predialysis CKD. A higher resolution version of the Graphical abstract is available as Supplementary information.

Assessment of the oral health status of children with chronic kidney disease

BACKGROUND

There are various oral symptoms related to the disease and its management in individuals with chronic kidney disease (CKD). The aim of the study was to investigate the oral health status of children with different stages of CKD, kidney transplant recipients (KTR), and healthy children.

METHODS

A total of seventy-one children diagnosed with CKD and fifty-two healthy children were included in the study. Each patient was examined for dental caries by the decayed-missing-filled-teeth (DMFT/dmft) index and the International Caries Detection and Assessment System (ICDAS-II), developmental defects of enamel (DDE) by the DDE index, and oral hygiene by the debris (DI), calculus (CI), and simplified oral hygiene (OHI-S) indices.

RESULTS

The median number of DMFT/dmft was 1.00 (interquartile range (IQR):1.00-4.00) in children with stage 1-3 CKD, 0.00 (IQR: 0.00-2.50) in stage 4-5 children, 0.00 (IQR: 1.00-3.00) in KTR, and 8.00 (IQR: 1.00-13.00) in healthy children. According to ICDAS-II categories, the percentage of children with severe caries was 53.8% in healthy children, while it was 44.4% in KTR, 25.9% in stage 1-3, and 11.4% in stage 4-5 children. While the percentage of children with DDE was 88.8% in KTR, 80% in stage 4-5, and 66.7% in stage 1-3 children, this rate was 44.2% in healthy children. The highest mean OHI-S score was observed in stage 4-5 children (2.10 ± 1.08), followed by KTR (1.46 ± 1.19), stage 1-3 (1.27 ± 0.61), and healthy children (0.45 ± 0.44), respectively.

CONCLUSIONS

Compared to healthy children, children with CKD had more debris accumulation, calculus formation, and more DDE but a lower severity of dental caries. A higher resolution version of the Graphical abstract is available as Supplementary information.

Glomerular capillary C3 deposition as a risk factor for unfavorable renal outcome in pediatric primary focal segmental glomerular sclerosis

Introduction

Some patients with primary focal segmental sclerosis (FSGS) demonstrate complement 3 (C3) deposition in glomerular capillary loops (Cap-C3) and/or mesangial area (Mes-C3). The clinicopathological and prognostic significance of C3 deposition remains incompletely investigated, especially in the pediatric cohort.

Methods

We retrospectively analyzed 264 children of biopsy-proven primary FSGS between January 2003 and December 2020. The correlation between Cap-C3 and renal outcome was evaluated by the Kaplan-Meier method and Cox multivariate regression analysis. Renal end-point event was defined as the development of end-stage renal disease, death for renal disease, or an estimated glomerular filtration rate reduction by at least 50% from baseline.

Results

Among the 264 patients, 30 (11.4%) had Cap-C3. Kaplan-Meier analysis showed that patients with Cap-C3 had significantly lower renal survival rates than patients without Cap-C3 (60.17% vs. 84.71% at 5 years, 39.49% vs. 65.55% at 10 years, P < 0.01). Cox multivariate regression analysis showed that Cap-C3 was an independent risk factor for poor renal outcome (HR 3.53, 95% CI 1.22-10.19, P = 0.02).

Conclusion

Glomerular capillary C3 deposition was an independent risk factor for unfavorable renal outcome in children with primary FSGS.

Evaluation of Arterial Stiffness and Carotid Intima-Media Thickness in Children with Primary and Renal Hypertension

Hypertension is an increasing disease in children and the risk of endothelial damage and target organ damage increases in the presence of additional risk factors such as obesity. In our study, the effect of hypertension on early atherosclerotic changes and target organ damage in children was investigated. Twenty four-hour ambulatory pulse wave analysis was performed by oscillometric method in 71 children aged 8-18 years, 17 of whom were diagnosed with primary hypertension without obesity, 18 had both primary hypertension and obesity, and 16 had renal hypertension. Twenty healthy normotensive children were included as the control group. Carotid intima-media thickness (CIMT) and Left Ventricular Mass Index were measured. Central systolic blood pressure (cSBP), central diastolic blood pressure (cDBP), systolic blood pressure (SBP) and diastolic blood pressure (DBP) were higher in the primary hypertension group compared to controls (p = 0.001, p = 0.005, p = 0.001, p = 0.009, respectively), cSBP was higher in the renal hypertension group than the control group (p = 0.018). There was no difference between the groups in terms of pulse wave analysis parameters, CIMT, or left ventricular mass index (p > 0.05). Pulse wave velocity was positively correlated with SBP, DBP, cSBP, cDBP (p < 0.001). Augmentation index was positively correlated with DBP and cDBP (p = 0.01, p = 0.002, respectively). Our findings show that high blood pressure is associated with arterial stiffness and target organ damage beginning in childhood. The detection of early atherosclerotic vascular changes using pulse wave analysis allows to take necessary precautions such as lifestyle changes to prevent target organ damage in hypertensive children.

Glomerular filtration rate in critically ill neonates and children: creatinine-based estimations versus iohexol-based measurements

BACKGROUND

Acute kidney injury (AKI) and augmented renal clearance (ARC), both alterations of the glomerular filtration rate (GFR), are prevalent in critically ill children and neonates. AKI and ARC prevalence estimates are based on estimation of GFR (eGFR) using serum creatinine (SCr), which is known to be inaccurate. We aimed to test our hypothesis that AKI prevalence will be higher and ARC prevalence will be lower in critically ill children when using iohexol-based measured GFR (mGFR), rather than using eGFR. Additionally, we aimed to investigate the performance of different SCr-based eGFR methods.

METHODS

In this single-center prospective study, critically ill term-born neonates and children were included. mGFR was calculated using a plasma disappearance curve after parenteral administration of iohexol. AKI diagnosis was based on the KDIGO criteria, SCr-based eGFR, and creatinine clearance (CrCL). Differences between eGFR and mGFR were determined using Wilcoxon signed-rank tests and by calculating bias and accuracy (percentage of eGFR values within 30% of mGFR values).

RESULTS

One hundred five children, including 43 neonates, were included. AKI prevalence was higher based on mGFR (48%), than with KDIGO or eGFR (11-40%). ARC prevalence was lower with mGFR (24%) compared to eGFR (38-51%). eGFR equations significantly overestimated mGFR (60-71 versus 41 ml/min/1.73 m², p < 0.001-0.002). Accuracy was highest with eGFR equations based on age- and sex-dependent equations (up to 59%).

CONCLUSION

Iohexol-based AKI prevalence was higher and ARC prevalence lower compared to standard SCr-based eGFR methods. Age- and sex-dependent equations for eGFR (eGFR-Smeets for neonates and eGFR-Pierce for children) best approached measured GFR and should preferably be used to optimize diagnosis of AKI and ARC in this population. A higher resolution version of the Graphical abstract is available as Supplementary information.

Kidney concentrating capacity in children with autosomal recessive polycystic kidney disease is linked to glomerular filtration and hypertension

BACKGROUND

Impaired kidney concentration capacity is present in half of the patients with autosomal dominant polycystic kidney disease (ADPKD). The kidney concentrating capacity was further impaired within the animal model of autosomal recessive polycystic kidney disease (ARPKD). To date, only one small study has investigated it in children having ARPKD. Therefore, we aimed to study the kidney concentrating ability in a larger cohort of children with ARPKD.

METHODS

Eighteen children (median age 8.5 years, range 1.3-16.8) were retrospectively investigated. A standardized kidney concentrating capacity test was performed after the application of a nasal drop of desmopressin (urine osmolality > 900 mOsmol/kg). The glomerular filtration rate was estimated using the Schwartz formula (eGFR) and blood pressure (BP) was measured as office BP.

RESULTS

Kidney concentrating capacity was decreased (urine osmolality < 900 mOsmol/kg) in 100% of children with ARPKD. The median urine osmolality after desmopressin application was 389 (range 235-601) mOsmol/kg. Sixteen patients (89%) were defined as hypertensive based on their actual BP level or their use of antihypertensive drugs. The maximum amounts of urinary concentration correlated significantly with eGFR (r = 0.72, p < 0.0001) and hypertensive scores (r = 0.50, p < 0.05), but not with kidney size. Twelve patients (67%) were defined as having CKD stages 2-4. The median concentrating capacity was significantly lower in children within this group, when compared to children with CKD stage 1 possessing a normal eGFR (544 mOsmol/kg, range 413-600 mOsmol/kg vs. 327 mOsmol/kg, range 235-417 mOsmol/l, p < 0.001).

CONCLUSIONS

Impaired kidney concentrating capacity is present in most children with ARPKD and is associated with decreased eGFR and hypertension. A higher resolution version of the Graphical abstract is available as Supplementary information.

Pediatric kidney transplants with multiple renal arteries show no increased risk of complications compared to single renal artery grafts

Background

Kidney allografts with multiple renal arteries (MRA) are not infrequent and have been historically associated with a higher risk of developing vascular and urologic complications. Reports of kidney transplantation using MRA allografts in the pediatric population remain scarce. The aim of this study was to evaluate if transplantation of allografts with MRA with a surgical intent of creating a single arterial inflow using vascular reconstruction techniques when required, and without the routine use of surgical drains or ureteral stents, is associated with an increased risk of complications when compared to single renal artery (SRA) grafts.

Methods

We retrospectively analyzed all pediatric renal transplant recipients performed by a single surgeon at our center between January 2015 and June 2022. Donor and recipient demographics, intraoperative data, and recipient outcomes were included. Recipients were divided into two groups based on SRA vs. MRA. Baseline variables were described using frequency distributions for categorical variables and means and standard errors for continuous variables. Comparisons of those distributions between the two groups were performed using standard chi-squared and t-tests. Time-to-event distributions were compared using the log-rank test.

Results

Forty-nine pediatric transplant recipients were analyzed. Of these, 9 had donors with MRA (Group 1) and 40 had donors with SRA (Group 2). Native kidney and liver mobilization was performed in 44.4% (4/9) of Group 1 vs. 60.0% (24/40) of Group 2 cases (p = 0.39). There were no cases of delayed graft function or graft primary nonfunction. No surgical drainage or ureteral stents were used in any of the cases. One patient in Group 2 developed a distal ureter stricture. The geometric mean serum creatinine at 6- and 12-months posttransplant was 0.7 */ 1.2 and 0.9 */ 1.2 mg/dl in Group 1 and 0.7 */ 1.1 and 0.7 */ 1.1 mg/dl in Group 2. Two death-censored graft failures were observed in Group 2, with no significant difference observed between the two groups (p = 0.48).

Conclusions

Our study demonstrates that pediatric renal transplantation with MRA grafts, using a surgical approach to achieve a single renal artery ostium, can be safely performed while achieving similar outcomes as SRA grafts and with a low complication rate.

Clinical Outcomes of Renal Replacement Therapy in Pediatric Acute Kidney Injury: A 10-Year Retrospective Observational Study

Children with severe acute kidney injury (AKI) have had a high mortality rate despite the use of advanced renal replacement therapy (RRT). This study aims to determine the clinical outcomes and the predictors of survival in pediatric AKI requiring RRT in Thailand. All patients aged 1 month to 18 years with AKI requiring RRT in the Department of Pediatrics, Ramathibodi Hospital from January 1st, 2010 to December 31st, 2019 were enrolled. Clinical and laboratory data were obtained through a medical record review. There were 92 patients with a 45% survival rate. Five factors associated with mortality included multi-organ dysfunction syndrome, presence of sepsis, high pediatric risk of mortality III, use of nephrotoxic drugs, and use of vasopressors. By multivariate analysis, the presence of sepsis and the use of nephrotoxic drugs were independently associated with mortality. Patients with fluid overload ≥10% was associated with poor survival.

Evaluation of Renal Function and Urinalysis in Children With Simple Febrile Convulsions

Febrile convulsion (FC) is the most prevalent type of seizure in children. Febrile diseases have been associated with alterations in kidney function and urine indices. Therefore, in this study, renal function and urine analysis were examined in children with simple FC. The study comprised children with simple FC who were referred to the Amirkabir hospital in Arak between 2020 and 2021. Children were examined for urinalysis and kidney function by assessing the estimated glomerular filtration rate (eGFR). A total of 157 patients with FC were admitted. Hematuria, proteinuria, and pyuria were detected in 8.9%, 1.9%, and 5.1% of cases, respectively. The urine cultures of 2 children were positive. Moreover, it was found that in simple FC, eGFR decreases regardless of gender (P > .05), although kidney function decreases more in children older than 24 months. In conclusion, all children with FC must undergo renal function assessments. Furthermore, urinalysis and urine culture are advised to rule out infection.

Whole exome sequencing identifies KIF26B, LIFR and LAMC1 mutations in familial vesicoureteral reflux

Vesicoureteral reflux (VUR) is a common urological problem in children and its hereditary nature is well recognised. However, despite decades of research, the aetiological factors are poorly understood and the genetic background has been elucidated in only a minority of cases. To explore the molecular aetiology of primary hereditary VUR, we performed whole-exome sequencing in 13 large families with at least three affected cases. A large proportion of our study cohort had congenital renal hypodysplasia in addition to VUR. This high-throughput screening revealed 23 deleterious heterozygous variants in 19 candidate genes associated with VUR or nephrogenesis. Sanger sequencing and segregation analysis in the entire families confirmed the following findings in three genes in three families: frameshift LAMC1 variant and missense variants of KIF26B and LIFR genes. Rare variants were also found in SALL1, ROBO2 and UPK3A. These gene variants were present in individual cases but did not segregate with disease in families. In all, we demonstrate a likely causal gene variant in 23% of the families. Whole-exome sequencing technology in combination with a segregation study of the whole family is a useful tool when it comes to understanding pathogenesis and improving molecular diagnostics of this highly heterogeneous malformation.

Acute kidney injury and childhood acute myeloid leukemia

BACKGROUND

Acute kidney injury (AKI) appears to be particularly common in children with acute myeloid leukemia (AML), although the epidemiology data on this patient population is sparse. The objective of this study was to assess the prevalence and factors associated with AKI in childhood AML during chemotherapy treatment.

METHODS

The medical records of 112 children aged under 15 years diagnosed with AML who received chemotherapy in a major tertiary-care referral center in southern Thailand were reviewed. Logistic regression was used to identify factors associated with AKI.

RESULTS

Fifty-six (50%) children had AKI events. The median time from AML diagnosis to the first AKI was 29.5 days (interquartile range: 11.0-92.8) and the median follow-up time was 10.9 months (interquartile range: 3.6-31.1). Age at diagnosis ≥ 10 years (OR 2.75, 95% CI 1.09-6.93), glomerular filtration rate < 90 mL/min/1.73 m² at AML diagnosis (OR 7.58, 95% CI 1.89-30.5), and septic shock (OR 22.0, 95% CI 4.63-104.3) were independently associated with AKI.

CONCLUSIONS

Childhood AML has a high rate of kidney injury with 50% having AKI. Age ≥ 10 years at diagnosis, impaired kidney function before treatment, and septic shock were strongly associated with AKI. A higher resolution version of the Graphical abstract is available as Supplementary information.

Time to Rethink the Current Paradigm for Assessing Kidney Function in Drug Development and Beyond

Chronic kidney disease (CKD) is an important health issue that affects ~ 9.1% of the world adult population. Serum creatinine is the most commonly used biomarker for assessing kidney function and is utilized in different equations for estimating creatinine clearance or glomerular filtration rate (GFR). The Cockcroft-Gault formula for adults and "original" Schwartz formula for children have been the most commonly used equations for estimating kidney function during the last 3-4 decades. Introduction of standardized serum creatinine bioanalytical methodology has reduced interlaboratory variability but is not intended to be used with Cockcroft-Gault or original Schwartz equations. More accurate equations (for instance, Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) for adults and bedside Schwartz or Chronic Kidney Disease in Children Schwartz equation for children) based on standardized serum creatinine values (and another biomarker-cystatin C) have been introduced and validated in recent years. Recently, the CKD-EPI equation refitted without a race variable was introduced. Clinical practice guidance in nephrology advocates a shift to these equations for managing health care of patients with CKD. The guidance also recommends use of albuminuria in addition to GFR for CKD diagnosis and management. Significant research with large data sets would be necessary to evaluate whether this paradigm would also be valuable in drug dose adjustments. This article attempts to highlight some important advancements in the field from a clinical pharmacology perspective and is a call to action to industry, regulators, and academia to rethink the current paradigm for assessing kidney function to enable dose recommendation in patients with CKD.

Arterial stiffness and nocturnal hypertension in preterm children and adolescents

BACKGROUND AND OBJECTIVES

Preterm birth has been associated with increased risk for developing hypertension and other chronic diseases during childhood and adulthood. The aim of the current prospective case-control study was to investigate the associations of preterm birth with ambulatory blood pressure (BP) levels and arterial stiffness during childhood and adolescence.

METHODS

The study population included 52 children and adolescents born preterm and 26 healthy children born full term with similar age. The participants underwent ambulatory BP monitoring (ABPM) and assessment of carotid-femoral pulse wave velocity (PWV).

RESULTS

Preterm children presented higher night SBP z score values compared to controls, but did not differ in other ABPM parameters, office peripheral and central SBPs. Nocturnal hypertension was found in 78% (7/9) of ex-preterm children with ambulatory BP hypertension. Preterm birth was an independent predictor of PWV z score adjusted for heart rate. Estimated marginal means for PWV z score adjusted for age, sex, presence of kidney disease at birth, office BPs, night BPs, central SBP, and BMI z scores were significantly higher in preterm individuals compared to controls (0.703, 95% confidence interval [CI] 0.431-0.975 versus -0.19, 95% CI -0.574-0.536, respectively, P  = 0.027). Preterm children who were overweight presented the highest values of night SBP and PWV z score.

CONCLUSION

Preterm birth is associated with higher nocturnal BP and increased arterial stiffness in childhood and adolescence. Increased awareness for detection of hypertension and prevention of obesity in childhood could prevent future adverse cardiovascular outcomes in preterm individuals.

Evolution of congenital anomalies of urinary tract in children with and without solitary kidney

BACKGROUND

We hypothesized that children with congenital solitary functioning kidney (CSFK) present forms of congenital urinary tract anomalies (CUTA) with higher chance of spontaneous resolution compared with patients with two kidneys.

METHODS

We retrospectively selected 75 consecutive children with CUTA of the CSFK and 75 matched patients with unilateral CUTA but without CSFK (controls) with prenatal suspicion of unilateral CUTA and early evaluation. We compared the spontaneous CUTA resolution and the prevalence of kidney injury between groups at last follow-up. Patients and controls were clustered under the categories of "severe" and "non-severe" CUTA.

RESULTS

The mean age at first and last follow-up was 0.17 ± 0.07 and 8.5 ± 5.2 years. Compared with controls, patients with CSFK had lower prevalence of severe CUTA at first evaluation; lower prevalence of febrile urinary tract infections, need of surgical correction, and higher rate of spontaneous CUTA resolution during follow-up; and a similar prevalence of mild kidney injury at last follow-up. CSFK compared with controls presented higher cumulative proportion of spontaneous resolution from severe CUTA (100 vs 41.8%; p < 0.001) and from the single CUTA sub-categories (severe vesicoureteral reflux, non-obstructive hydronephrosis, and megaureter).

CONCLUSIONS

CSFK patients had lower prevalence of severe forms and better outcomes of their CUTA compared with controls.

IMPACT

One-third of patients with congenital solitary functioning kidney (CSFK) present congenital urinary tract anomalies (CUTA) and manifest poorer outcomes compared with CSFK without CUTA. CSFK patients had lower prevalence of severe forms and better outcomes of their CUTA in spite of similar prevalence of kidney injury compared with controls. This adds evidence about disturbed nephrogenesis in CSFK patients and emboldens conservative management of many of their non-obstructive CUTA.

Current antihypertensive treatment and treatment-resistant hypertension in Japanese patients with chronic kidney disease

BACKGROUND

Hypertension is an important prognostic predictor in patients with chronic kidney disease (CKD), and the recommended target blood pressure has been continuously revised. This study aimed to reveal the current antihypertensive practices in Japanese patients with CKD.

METHODS

In the Fukuoka Kidney disease Registry, we extracted 3664 non-dialysis-dependent patients with CKD. Apparent treatment-resistant hypertension (aTRH) was defined as a failure of blood-pressure control treated with three antihypertensive medication classes or a treatment with ≥ 4 classes regardless of blood pressure. The blood-pressure control complied with the target blood pressure recommended by the KDIGO 2012 guideline.

RESULTS

The median age of the patients was 67 years, body mass index (BMI) was 23 kg/m², and estimated glomerular filtration rate (eGFR) was 40 mL/min/1.73 m². The number of patients with unachieved blood-pressure control was 1933, of whom 26% received ≥ 3 classes of antihypertensive medications. The first choice of medication was renin-angiotensin system inhibitors, followed by calcium-channel blockers. The rate of thiazide use was low in all CKD stages (3-11%). The prevalence of aTRH was 16%, which was significantly associated with BMI (odds ratio [95% confidence interval] per 1-standard deviation change, 1.38 [1.25-1.53]), decreased eGFR (1.87 [1.57-2.23]), as well as age, diabetes mellitus, and chronic heart disease.

CONCLUSIONS

Renal dysfunction and obesity are important risk factors of aTRH. Even under nephrologist care, most patients were treated with insufficient antihypertensive medications. It is important to prescribe sufficient classes of antihypertensive medications, including diuretics, and to improve patients' lifestyle habits.

Diffusion Tensor Imaging of the Dentate Nucleus After Repeated Administration of Gadobutrol in Children

This study aimed to investigate possible signal changes in the dentate nucleus (DN) on diffusion tensor imaging (DTI) after administration of gadobutrol in a pediatric cohort. Total of 50 pediatric patients (mean age: 6.2 ± 4.3 years) with normal renal function exposed exclusively to the macrocyclic GBCA (mcGBCA) gadobutrol and 50 age- and sex-matched control patients with nonpathological neuroimaging findings (and no GBCA administration). Mean diffusivity (MD) and fractional anisotropy (FA) values were determined in the DN. A paired t test was performed to compare FA, MD values, and DN-to-middle cerebral peduncle (MCP) T1WI SI ratios between children exposed to gadobutrol and controls. Pearson correlation analysis was conducted to determine any correlation between FA and MD values as well as T1WI SI ratios and confounding parameters. The mean FA values of DN was significantly lower in children with mcGBCA than in the control group (p < 0.001; non-GBCA group, 0.299 ± 0.03; mcGBCA group, 0.254 ± 0.05), but no significant difference of the T1WI SI ratio was noted between the mcGBCA group (0.946 ± 0.06) and the control group (0.963 ± 0.05; p = 0.336). There was also a significant MD value difference between mcGBCA group and control group (p < 0.001; non-GBCA group, 0.152 ± 0.02 × 10^-3 mm²/s; mcGBCA group, 0.173 ± 0.03 × 10^-3 mm²/s). A significant correlation was identified between FA/MD values and the number of mcGBCA administration (FA; correlation coefficient =  - 0.355, p = 0.011 and MD; correlation coefficient = 0.334, p = 0.018). The administration of the gadobutrol was associated with higher MD and lower FA values in DN suggesting a difference in cerebellar tissue integrity between children exposed to mcGBCAs and control group.

Prospective Evaluation of Kidney Function in Long-Term Survivors of Pediatric CNS Tumors

Purpose: Numerous acute effects of chemotherapeutics on kidney function are well described. However, data on the long-term effects of chemotherapy in the growing population of childhood central nervous system (CNS) tumor survivors is limited. We aimed to evaluate the kidney function of a cohort of long-term CNS tumor survivors treated with different standard chemotherapeutic regimens. Methods: Patients treated for a CNS tumor were prospectively evaluated up to 12 years after completion of their therapy. Examination of kidney function was performed during routine follow-up visits. Blood pressure and blood and urine parameters were analyzed for kidney function evaluation. Glomerular function was assessed by calculating the estimated glomerular filtration rate (eGFR), tubular functions were analyzed by measuring serum electrolytes, bicarbonate and phosphate reabsorption, and proteinuria was assessed by calculating the protein/creatinine ratio and phosphate reabsorption. Results: None of the 65 patients evaluated suffered from clinically relevant kidney impairment (eGFR < 90 mL/min/L, 73 m2). There was no association between chemotherapy dose and eGFR. Only two patients showed mild signs of tubulopathy and 11 patients were diagnosed with elevated blood pressure. Conclusion: With adequate supportive measures, such as sufficient hydration according to chemotherapy protocol guidelines, as well as avoidance or close monitoring of additional nephrotoxic medication, impaired kidney function is rare in CNS tumor survivors treated with standard chemotherapy. Nonetheless, long-term follow-up is essential for early detection of mild impairment of kidney function.

The Association of Controlling Nutritional Status Score and Prognostic Nutritional Index with Cardiovascular Diseases: the Fukuoka Kidney Disease Registry Study

AIM

The Controlling Nutritional Status (CONUT) score and the Prognostic Nutritional Index (PNI) reflect the immunonutritional status of patients. However, the associations of these two indices with cardiovascular disease (CVD) have not been characterized in patients with chronic kidney disease (CKD). Therefore, the current study aimed to determine whether the CONUT score or PNI was associated with prior CVD in patients with CKD.

METHODS

A cross-sectional study of 2,751 patients with CKD who were not on dialysis was performed. The patients were grouped into tertiles (T1-T3) of PNI and placed into three groups following their CONUT score: low- (CONUT score, 0), mild- (CONUT score, 1-2), and moderate-to-high- (CONUT score, ≥ 3) risk groups.

RESULTS

Prior CVD was present in 655 (24%) of the participants. Multivariable logistic regression analyses, with adjustment for potential confounders, showed that high CONUT score was associated with prior CVD than the low score (mild-risk group: odds ratio [OR]=1.35, 95% confidence interval [CI]=1.04-1.76; moderate-to-high-risk group: OR=1.66, 95% CI=1.19-2.30). In addition, the lower PNI tertiles were independently associated with prior CVD compared with T3 of PNI (T1: OR=1.45, 95% CI=1.09-1.92; T2: OR=1.32, 95% CI=1.01-1.72).

CONCLUSIONS

Both CONUT score and PNI were found to be independently associated with prior CVD in patients with CKD in the present cross-sectional study. A longitudinal study is needed to elucidate whether these two indices are associated with subsequent cardiovascular events.

Diagnostic Performance of Height-Estimated Baseline Creatinine in Diagnosing Acute Kidney Injury in Children with Type 1 Diabetes Mellitus Onset

At type 1 diabetes mellitus (T1DM) onset, acute kidney injury (AKI) is very common. To diagnose AKI, the availability of a baseline serum creatinine (bSCr) is pivotal. However, in most hospitalized children the bSCr is unknown. We aimed to test whether the bSCr estimated on the basis of height (ebSCr) could be a reliable surrogate for AKI diagnosis compared with the measured bSCr (mbSCr). As the mbSCr, we considered the creatinine measured 14 days after T1DM onset while ebSCr (mg/dL) = (k × height [cm])/120 mL/min/1.73 m2, where k = 0.55 for children and adolescent girls and k = 0.7 for adolescent boys. AKI was defined as serum creatinine values >1.5 times the baseline creatinine. Kappa statistics and the percentage of agreement in AKI classification by ebSCr−AKI versus mbSCr−AKI definition methods were calculated. Bland−Altman plots were used to show the agreement between the creatinine ratio (highest/baseline creatinine; HC/BC) calculated with mbSCr and ebSCr. The number of 163 patients with T1DM onset were included. On the basis of mbSCr, 66/163 (40.5%) presented AKI while, on the basis of ebSCr, 50/163 (30.7%) accomplished AKI definition. ebSCr showed good correlation with mbSCr using both the Spearman test (rho = 0.67; p < 0.001) and regression analysis (r = 0.68; p < 0.001). Moreover, at the Bland−Altman plots, the bias of the highest/baseline creatinine ratio calculated on the basis of the mbSCr compared to ebSCr was minimal (bias = −0.08 mg/dL; 95% limits of agreement = −0.23/0.39). AKI determined using ebSCr showed 90% agreement with AKI determined using mbSCr (kappa = 0.66; p < 0.001). Finally, we compared the area under a receiver−operating characteristic curve (AUROC) of HC/BC ratio calculated on the basis of ebSCr with AUROC of the gold standard HC/BC ratio calculated on the basis of mbSCr. As expected, the gold standard had an AUROC = 1.00 with a 95% confidence interval (CI) between 0.98 and 1.00, p < 0.001. The HC/BC ratio calculated on the basis of ebSCr also had significant AUROC (AUROC = 0.94; 95% CI: 0.90−0.97; p < 0.001). The comparison of the two ROC curves showed a p < 0.001. In conclusion, when mbSCr is unknown in patients with T1DM onset, the ebSCr calculated on the basis of height could be an alternative to orientate clinicians toward AKI diagnosis.

Nutritional and health status of a cohort of school-age children born to mothers treated for severe acute malnutrition in their childhood in The Democratic Republic of Congo

Background

Malnutrition is a public health problem, but outside the theoretical framework, little is known about the concrete intergenerational effects of malnutrition.

Objective

The objective of this study is to compare the nutritional status and health indicators of school children born to mothers who were treated for severe acute malnutrition (SAM).

Methodology

The study took place in Miti-Murhesa health zone in the Democratic Republic of Congo. This is a cohort study assessing the nutritional and health status of school children born to mothers who had been treated for SAM, based on WHZ or edema, in Lwiro hospital between 1988–2002 compared to children born to mothers who were not exposed to SAM. Stunting and thinness were evaluated by Height for Age Z-score (HAZ) and Body Mass Index by Age criteria (BMIAZ) respectively. On admission, blood samples were taken to assess anemia, HIV serology, hemogram and others biological indicators. Stool’s examinations were conducted by using Olympus optical microscope. Parametric and non-parametric tests were applied to compare the different variables in two groups.

Results

We identified 106 children aged 5–16 years (103 exposed and 58 unexposed) and we received 83.5% and 91.4% children respectively for anthropometric parameters. The mean of age was 7.9 ± 2.4 year in exposed group and 7.4 ± 2.1 year in unexposed group (p = 0.26). The prevalence of stunting was 68.3% in the exposed group and 67.3% in the unexposed group (p = 0.90). The prevalence of thinness was 12.8% in the exposed group and 9.6% in the unexposed group (p = 0.57). The biological profile (glycemia, urea, creatinine and hemogram) and the prevalence of intestinal parasites were similar in the two groups.

Conclusion

In this sample, in a malnutrition-endemic area, there was no statistically significant difference in nutrition and health indicators between school children born to mothers exposed to SAM and their community controls.

Effects of Concomitant Administration of PXR Ligand Drugs on the Anticoagulant Effects of Warfarin

We encountered cases in which the anticoagulant effects of warfarin (CYP2C9 substrate) were reversibly attenuated by the concomitant administration of rifampicin or bosentan, which are potent pregnane X receptor (PXR) ligands. The purpose of the present study is to report the previous case with rifampicin, and to evaluate the changes in the warfarin anticoagulant effects when withdrawing or switching bosentan treatment. The former is a case study of a 4-year-old girl undergoing warfarin treatment. The latter is a longitudinal study of 20 pediatric patients receiving stable warfarin treatment. The prothrombin time and international normalized ratio (PT-INR) values were extracted from the medical records and normalized by the daily-dose per body size as an index for the warfarin anticoagulant effects. Rifampicin treatment resulted in a 52.0% decrease in the anticoagulant index. On the other hand, 10 of 20 patients started bosentan and their anticoagulant index was reduced by a median of 2.00. Bosentan was withdrawn in 4 of 20 patients and their anticoagulant index increased by a median of 3.67. Six of 20 patients switched from bosentan to macitentan, which is considered not to activate PXR in clinical settings. However, switching from bosentan to macitentan resulted in a median of 2.25 reduction of the anticoagulant index rather than recovery of the response to warfarin. This study suggests not only the possibility of heterogeneity in the response to PXR activation and deactivation, but also the importance of long-term monitoring of drug-drug interactions when switching from bosentan to macitentan.

Impact of nephrotoxic drugs on urinary biomarkers of renal function in very preterm infants

BACKGROUND

Following preterm birth, the immature kidney is exposed to several harmful conditions, with an increased risk of renal impairment. We aimed to assess urinary biomarkers of renal function in very preterm infants during early nephrotoxic treatments.

METHODS

Infants ≤32 weeks' gestation and ≤1500 g were enrolled in this observational prospective study. Urine samples were collected on day 1(T1), 2-4(T2), 5-7(T3), 8-10(T4), 11-13(T5). The following urinary biomarkers were determined: osteopontin (uOPN), epidermal growth factor (uEGF), neutrophil gelatinase-associated lipocalin (uNGAL), cystatin C (uCysC). The infants were grouped according to their exposure to amikacin or ibuprofen during the study period and a between-group comparison of urinary biomarkers at each time point was performed.

RESULTS

Thirty-six infants were included. Urinary CysC, uOPN, and uNGAL rose significantly during ibuprofen or amikacin treatment, while no difference was observed for uEGF. After adjustment for possible influencing factors, amikacin administration was associated with higher uCysC at T1 (p = 0.007) and T2 (p = 0.016), whereas ibuprofen increased uOPN (p = 0.001) and uNGAL concentration (p = 0.009) at T3.

CONCLUSION

Nephrotoxic therapies induce molecule-specific change patterns of renal function biomarkers in treated preterm infants. Serial assessments of these biomarkers may aid to identify neonates at risk of renal impairment and to develop tailored therapeutic approaches.

IMPACT

Despite the wide use of nephrotoxic therapies in neonatal settings, little is known on their effect on renal function biomarkers in preterm infants. This study describes molecule-specific change patterns of urinary biomarkers during ibuprofen and amikacin administration, suggesting underlying pathophysiological effects on renal function. Given their low analytical costs and non-invasive collection, the urinary biomarkers investigated in this study represent a promising strategy for serial monitoring of renal function in at-risk neonates and may aid the early detection of renal function impairment at different kidney levels during nephrotoxic treatments.

Clinical, Pathological, and Genetic Characteristics in Patients with Focal Segmental Glomerulosclerosis

Background

Approximately 30% of children with steroid-resistant nephrotic syndrome (SRNS) have causative monogenic variants. SRNS represents glomerular disease resulting from various etiologies, which lead to similar patterns of glomerular damage. Patients with SRNS mainly exhibit focal segmental glomerulosclerosis (FSGS). There is limited information regarding associations between histologic variants of FSGS (diagnosed using on the Columbia classification) and monogenic variant detection rates or clinical characteristics. Here, we report FSGS characteristics in a large population of affected patients.

Methods

This retrospective study included 119 patients with FSGS, diagnosed using the Columbia classification; all had been referred to our hospital for genetic testing from 2016 to 2021. We conducted comprehensive gene screening of all patients using a targeted next-generation sequencing panel that included 62 podocyte-related genes. Data regarding patients' clinical characteristics and pathologic findings were obtained from referring clinicians. We analyzed the associations of histologic variants with clinical characteristics, kidney survival, and gene variant detection rates.

Results

The distribution of histologic variants according to the Columbia classification was 45% (n=53) FSGS not otherwise specified, 21% (n=25) cellular, 15% (n=18) perihilar, 13% (n=16) collapsing, and 6% (n=7) tip. The median age at end stage kidney disease onset was 37 years; there were no differences in onset age among variants. We detected monogenic disease-causing variants involving 12 of the screened podocyte-related genes in 34% (40 of 119) of patients. The most common genes were WT1 (23%), INF2 (20%), TRPC6 (20%), and ACTN4 (10%). The perihilar and tip variants had the strongest and weakest associations with detection of monogenic variants (83% and 0%, respectively; P<0.001).

Conclusions

We revealed the distributions of histologic variants of genetic FSGS and nongenetic FSGS in a large patient population. Detailed data concerning gene variants and pathologic findings are important for understanding the etiology of FSGS.

Maturation of Glomerular Filtration Rate in Term-Born Neonates: An Individual Participant Data Meta-Analysis

Background: The evidence from individual studies to support the maturational pattern of glomerular filtration rate (GFR) in healthy term-born neonates is inconclusive. We performed an individual participant data (IPD) meta-analysis of reported measured GFR (mGFR) data aimed to establish neonatal GFR reference values. Furthermore, we aimed to optimise neonatal creatinine-based GFR estimations Methods: We identified studies reporting mGFR measured by exogenous markers or creatinine clearance (CrCL) in healthy term-born neonates. The relationship between postnatal age and clearance was investigated using cubic splines with generalized additive linear mixed models. From our reference values, we estimated an updated coefficient for the Schwartz equation (eGFR(ml/min/1.73m²)=(k*height (cm))/serum creatinine(mg/dl)). Results: Forty-eight out of 1521 screened articles reported mGFR in healthy term-born neonates, and 978 mGFR values from 881 neonates were analysed. IPD were available for 367 neonates and the other 514 neonates were represented by 41 aggregated data points as means/medians per group. GFR doubled in the first five days after birth from 19.6 (95%CI 14.7;24.6) ml/min/1.73m² to 40.6 (95%CI 36.7;44.5) ml/min/1.73m², then more gradually increased to 59.4 (95%CI 45.9;72.9) ml/min/1.73m² by four weeks of age. A coefficient of 0.31 to estimate GFR best fitted the data. Conclusions: These reference values for healthy term-born neonates show a biphasic increase in GFR with the largest increase between days 1 and 5. Together with the re-examined Schwartz equation, this can help identify altered GFR in term-born neonates. To enable widespread implementation of our proposed eGFR equation, validation in a large cohort of neonates is required.

Can we predict early renal impairment in pediatric cirrhosis?

AIMS

Published literature on renal dysfunction (RD) in pediatric cirrhosis are limited. We aimed to detect early RD in cirrhotic children by renal resistive index (RI) and plasma aldosterone (PA). We evaluated the effects of large-volume paracentesis (LVP) and albumin infusion on the same.

METHODS

Non-azotemic cirrhotic children with tense ascites (undergoing LVP with albumin infusion) were prospectively enrolled. Blood biochemistry and doppler ultrasonography for RI and PA were measured at regular intervals. RI >0.7 was considered as RD. Outcomes were noted at D90 and 1 year. Chronic liver disease children without ascites were included as controls.

RESULTS

Of the 99 cirrhotic children, tense ascites (n=51) had higher baseline RI than controls (n=48) (p<0.001). Overall, baseline RD was observed in 32% and was significantly higher in tense ascites compared to controls (59% vs. 4%, p<0.001). Tense ascites with RD at admission had higher chances of acute kidney injury (AKI) (p=0.009), ascites recurrence (p=0.043), hospital readmission (p=0.048), and mortality (p=0.009) compared to patients without RD by D90. Significant reduction in RI was noted at 48 h, D7, D30, and D90 compared to baseline after LVP with albumin. Pediatric End-stage Liver Disease (PELD) score and PA had a strong positive correlation with baseline RI (R²=0.51, R²=0.47). Using multivariate analysis, PELD score and PA were predictors of AKI (odds ratio [OR]: 1.14; 95% confidence interval [CI]: 1.04-1.24; p=0.003) and mortality (OR: 1.82; 95% CI: 1.22-2.72; p=0.004), respectively.

CONCLUSIONS

Abnormal baseline RI can be used as an early predictor of RD and predict long-term renal ouctomes in pediatric cirrhosis. Baseline RI correlated well with the severity of liver disease and PA. Paracentesis and albumin infusion effectively reduced RI.

Serum Homocysteine Level Is Positively Correlated With Serum Uric Acid Level in U.S. Adolescents: A Cross Sectional Study

Background

Physiologically, the levels of homocysteine (Hcy) and serum uric acid (SUA) are closely related; however, clinical studies on the relationship between Hcy and SUA have drawn different conclusions and have not analyzed this association among adolescents. This study therefore aimed to evaluate the relationship between Hcy and SUA levels among adolescents.

Methods

In this study, we performed a cross-sectional analysis of data from the National Health and Nutrition Examination Survey for the period 1999–2006, which included 5,404 adolescents aged 12–19 years. An elevated SUA level was defined as ≥5.5 mg/dL. Multivariate logistic regression and multivariate linear regression models were also applied in this study.

Results

The mean concentrations of Hcy and SUA were 6.0 μmol/L and 5.0 mg/dL, respectively, and 33.6% of the participants had SUA levels of ≥5.5 mg/dL. There was a dose–response relationship between Hcy and SUA, and Hcy was linearly positively correlated with SUA. The β value [95% confidence interval (CI)] for SUA in the fully adjusted model was1.43 (95% CI: 1.18, 1.68). The multivariate logistic regression model showed that per 1 increment in log-transformed Hcy, the risk of elevated SUA levels increased by 8.80 times (odds ratio, 8.80, 95% CI: 4.25, 18.20). Subgroup analyses showed that the relationship between Hcy and SUA was significantly different according to sex, age, body mass index (BMI), and estimated glomerular filtration rate (eGFR) stratification (P for interaction <0.05).

Conclusion

Hcy levels were positively correlated with SUA levels and elevated SUA levels among U.S. teenagers, and this effect was more significant among boys aged ≥17 years and among people with lower BMI and eGFR.

Early unhealthy eating habits underlie morpho-functional changes in the liver and adipose tissue in male rats

Early-life consumption of high-fat and sugar-rich foods is recognized as a major contributor for the onset of metabolic dysfunction and its related disorders, including diabetes and nonalcoholic fatty liver disease. The lifelong impact of early unhealthy eating habits that start at younger ages remains unclear. Therefore, to better understand the effects of diet, it is essential to evaluate the structural and functional changes induced in metabolic organs and potential mechanisms underlying those changes. To investigate the long-term effects of eating habits, young male rats were exposed to high-sugar and high-energy diets. After 14 weeks, body composition was assessed, and histopathological changes were analyzed in the liver and adipose tissue. Serum biochemical parameters were also determined. Expression of inflammatory markers in the liver was evaluated by immunohistochemistry. Our results revealed that serum levels of glucose, creatinine, aspartate transaminase (AST), alanine transaminase (ALT), and lipid profile were increased in rats red high-sugar and high-energy diets. Histopathological alterations were observed, including abnormal hepatocyte organization and lipid droplet accumulation in the liver, and abnormal structure of adipocytes. In both unhealthy diet groups, hepatic expression of Toll-like receptor 4 (TLR4), cyclooxygenase 2 (COX-2), and E-selectin were increased, as well as a biomarker of oxidative stress. Together, our data demonstrated that unhealthy diets induced functional and structural changes in the metabolic organs, suggesting that proinflammatory and oxidative stress mechanisms trigger the hepatic alterations and metabolic dysfunction.

Long-term follow-up of patients after acute kidney injury in the neonatal period: abnormal ambulatory blood pressure findings

Background

Data on the long-term effects of neonatal acute kidney injury (AKI) are limited.

Methods

We invited 302 children who had neonatal AKI and survived to hospital discharge; out of 95 patients who agreed to participate in the study, 23 cases were excluded due to primary kidney, cardiac, or metabolic diseases. KDIGO definition was used to define AKI. When a newborn had no previous serum creatinine, AKI was defined as serum creatinine above the mean plus two standard deviations (SD) (or above 97.5^th percentile) according to gestational age, weight, and postnatal age. Clinical and laboratory features in the neonatal AKI period were recorded for 72 cases; at long-term evaluation (2–12 years), kidney function tests with glomerular filtration rate (eGFR) by the Schwartz formula, microalbuminuria, office and 24-h ambulatory blood pressure monitoring (ABPM), and kidney ultrasonography were performed.

Results

Forty-two patients (58%) had stage I AKI during the neonatal period. Mean age at long-term evaluation was 6.8 ± 2.9 years (range: 2.3–12.0); mean eGFR was 152.3 ± 26.5 ml/min/1.73 m². Office hypertension (systolic and/or diastolic BP ≥ 95^th percentile), microalbuminuria (> 30 mg/g creatinine), and hyperfiltration (> 187 ml/min/1.73 m²) were present in 13.0%, 12.7%, and 9.7% of patients, respectively. ABPM was performed on 27 patients, 18.5% had hypertension, and 40.7% were non-dippers; 48.1% had abnormal findings. Female sex was associated with microalbuminuria; low birth weight (< 1,500 g) and low gestational age (< 32 weeks) were associated with hypertension by ABPM. Twenty-three patients (33.8%) had at least one sign of microalbuminuria, office hypertension, or hyperfiltration. Among 27 patients who had ABPM, 16 (59.3%) had at least one sign of microalbuminuria, abnormal ABPM (hypertension and/or non-dipping), or hyperfiltration.

Conclusion

Even children who experienced stage 1 and 2 neonatal AKI are at risk for subclinical kidney dysfunction. Non-dipping is seen in four out of 10 children. Long-term follow-up of these patients is necessary.

Extended genetic analysis of exome sequencing for primary hyperoxaluria in pediatric urolithiasis patients with hyperoxaluria

PURPOSE

Next generation sequencing-based exome sequencing can be used to identify genetic abnormalities in patients believed to be suffering from primary hyperoxaluria. We outline our efforts to improve the diagnostic capacity of exome sequencing for these patients.

METHODS

We conducted a retrospective analysis of exome sequencing data from 77 pediatric urolithiasis patients with hyperoxaluria of unknown origin. Canonical exome sequencing analysis was performed to identify pathogenic variants in three known primary hyperoxaluria-related genes (AGXT, GRHPR, HOGA1) as per the guidelines of the American College of Medical Genetics. Then, extended exome sequencing analyses of 5'-untranslated region, non-canonical splicing site and copy number variant were performed on patients with negative diagnostic results in these three genes.

RESULTS

Canonical exome sequencing analyses led to the diagnosis of primary hyperoxaluria in 20/77 (26%) patients, including eight, four, and eight patients diagnosed with type 1, 2 and 3 primary hyperoxaluria, respectively. Non-canonical splicing site analyses discovered a pathogenic variant in the HOGA1 gene, which led to the diagnosis of six additional patients with type 3 primary hyperoxaluria, while copy number variant analyses from exome sequencing data identified a 1.8 kb copy number loss that impacted the AGXT gene, resulting in the diagnosis of an additional type 1 primary hyperoxaluria case.

CONCLUSIONS

Extended non-canonical splicing site and copy number variant analyses improve the diagnostic yield of canonical exome sequencing analysis for primary hyperoxaluria from 26% (20/77) to 35% (27/77) in 77 pediatric urolithiasis patients with hyperoxaluria.