Pediatric Nephrology最新文献

Background: Serum creatinine (SCr), the most used biomarker to evaluate glomerular filtration rate (GFR), might be inaccurate in children with sickle cell anemia (SCA). In this context, cystatin C (SCys) could be of interest. This study evaluated the performance of commonly used SCr- and SCys-based estimated GFR (eGFR) equations in African children with SCA.

Methods: This cross-sectional study included 109 steady-state children with SCA aged 3-18 years, from the Democratic Republic of Congo. Measured GFR (mGFR) was obtained using iohexol plasma clearance. eGFR was calculated using commonly used SCr- and SCys-based equations in children. The performance of these equations was evaluated by calculating the bias, precision, and accuracy within 30% (P30) of mGFR.

Results: The mean age of participants was 9.9 ± 4.2 years, and 48.6% were female. The median mGFR was 142 (IQR 119-169) mL/min/1.73 m². Of the equations studied, the FAS-Age SCr had the lowest bias (0.9 mL/min/1.73 m²). However, the 95% limit of agreement was very wide (-80.3 to + 81.6). SCr failed to rise in an age-dependent manner, reflecting a progressive loss of muscle mass or increased tubular secretion. All SCys-based equations underestimated GFR and failed to detect hyperfiltration, but there was no age-related change in bias.

Conclusion: These data show that all common eGFR equations using SCr or SCys poorly predict mGFR in African children with SCA. SCr-based equations potentially miss a decline in kidney function, which suggests that SCys could be the preferred marker in this population.

Background: The global survival rate of preterm infants has been progressively increasing. However, concerns regarding their long-term prognosis persist. This study aimed to investigate podocyte mRNA loss in 3-5-year-old full-term and preterm children to elucidate the role of podocyte depletion in the pathogenesis of chronic kidney disease (CKD) in preterm infants.

Methods: A total of 80 children aged 3-5 years, born at Tianjin Central Hospital of Gynecology and Obstetrics, were included in this study: 42 preterm infants (gestational age 24-29 weeks) and 38 full-term infants. Morning urine samples were collected to examine podocyte mRNA levels (expressed as the urinary podocin mRNA-to-creatinine ratio, UpodCR), urine protein, and urine albumin levels. The impact of perinatal factors on UpodCR was also analyzed.

Results: Results indicated that the rate of podocyte mRNA loss in the preterm group was significantly higher than in the full-term group (1.54-fold). No significant differences were observed in urine protein and urine albumin levels between the two groups. Perinatal factor analysis revealed that gestational age and antenatal corticosteroid use were significant risk factors for podocyte loss in childhood.

Conclusions: This study is the first to confirm accelerated podocyte loss in the urine of 3-5-year-old preterm children. Although less severe than in the early postnatal period, it remains higher than in full-term children, providing crucial evidence for the involvement of podocyte depletion in the pathogenesis of preterm-related CKD. It also underscores the need for careful evaluation of the benefits and risks associated with antenatal corticosteroid use.

Proteinuria is a common laboratory finding in adolescents. It is often benign and due to transient causes or orthostatic proteinuria. However, it can also be an early sign of underlying conditions that may lead to long-term kidney damage. Early recognition and appropriate diagnostic evaluation are crucial to preventing or slowing disease progression. In this age group, proteinuria may result from newly diagnosed diseases, pre-existing conditions that become clinically evident during adolescence, or previously undiagnosed disorders. Additionally, several proteinuric conditions are specific to this age group, including those related to obesity, recreational drug use, and anabolic androgenic steroids, all of which have increased significantly in recent decades. Adolescence is a transitional phase between childhood and adulthood that presents unique diagnostic challenges due to reduced parental involvement, frequent underreporting of symptoms, and non-compliance with pharmacological treatment or diet. Furthermore, adolescents may receive care in either pediatric or adult settings, where clinical approaches and guidelines often differ. This educational review addresses the diagnostic approach to proteinuria in adolescents and aims to propose a unified algorithm for this age group.

Background: Children receiving kidney replacement therapy frequently face complications resulting in recurrent hospitalizations. This nationwide retrospective observational study, conducted using data from the Italian Registry of Pediatric Chronic Dialysis (IRPCD), aimed to compare hospitalization rates and causes between children treated with chronic peritoneal dialysis (PD) and hemodialysis (HD).

Methods: The study included children (< 18 years) on chronic PD or HD recorded between January 2000 and December 2019. Hospitalizations were defined as admissions involving at least one overnight stay, excluding those for dialysis initiation or kidney transplantation. Hospitalization causes were categorized as infectious and non-infectious dialysis-related complications, other infections, non-infectious conditions, diagnostic procedures, and complications related to kidney failure.

Results: A total of 847 dialysis patients (493 on PD, 354 on HD) were included. Among 813 patients, 420 (51.7%) were hospitalized, with PD accounting for 72.9% at the first hospitalization. Dialysis-related infections were the most common cause (24.3%), particularly in PD patients, followed by non-infectious medical conditions (17.3%) and kidney failure-related complications (14.9%). Cox modeling indicated a lower risk of hospitalization for HD compared to PD (aHR 0.75 [95%CI 0.65-0.87]), with HD showing a protective effect over time. HD patients also had a lower likelihood of treatment changes after one year compared to PD (aHR 0.29 [95%CI 0.10-0.81]).

Conclusions: This study highlights the significant burden of hospitalization among children on chronic dialysis, with PD patients experiencing higher risks over time compared to HD. These findings underscore the need for targeted strategies to mitigate hospitalization risks in pediatric dialysis populations.

BK polyomavirus-associated nephropathy is a significant therapeutic challenge in kidney transplant recipients, often leading to allograft dysfunction. We report on a 12-year-old male kidney transplant recipient with severe, biopsy-proven BK polyomavirus-associated nephropathy and concurrent JC polyomavirus (JCPyV)-associated neurological symptoms. Due to failure of standard therapy, adoptive transfer of partially HLA-matched, BK polyomavirus-specific T cells from the kidney donor was administered as rescue therapy. The intervention induced a rapid decline in both BK polyomavirus (BKPyV) and JCPyV viral loads. This virological response was accompanied by the resolution of neurological symptoms and stabilization of allograft function. This case indicates that donor-derived BK polyomavirus-specific T cells represent a viable therapeutic modality for severe, refractory polyomavirus disease.

Background: Hyperkalemia following nephrectomies in children is a poorly studied, potentially life-threatening complication. We describe the frequency and risk factors for hyperkalemia in pediatric patients who underwent nephrectomies resulting in an anephric state.

Methods: This was a single center retrospective cohort study of patients < 21y who underwent nephrectomies resulting in an anephric state. Possible predictors included age, sex, preoperative potassium value, preoperative dialysis modality, preoperative urine output, procedure type, surgical approach, intraoperative lactated Ringer's (LR), and intraoperative blood. The primary outcome was intraoperative and postoperative day 0 and day 1 hyperkalemia. Hyperkalemia was defined as potassium > 5.1 mEq/L (severe > 5.9) in children ≥ 1y and > 5.5 (severe > 6.1) in children < 1y. Treatments for hyperkalemia were recorded. We examined associations with hyperkalemia using Wilcoxon rank-sum test, Pearson's Chi-squared test, or Fisher's exact test. We used Youden's Index to determine the preoperative potassium cutoff for predicting hyperkalemia.

Results: Among 46 patients who underwent nephrectomies resulting in an anephric state, 23 (50%) experienced hyperkalemia that was severe in 18 (39%), treated in 21 (46%), and precipitated transfer to the intensive care unit in 5 (11%). In unadjusted analysis, higher preoperative potassium (p < 0.001) and intraoperative LR (p = 0.018) were associated with a higher risk of postoperative hyperkalemia. A preoperative potassium of >3.85 mEq/L was associated with the development of hyperkalemia (p < 0.001).

Conclusions: Clinically important hyperkalemia is a common complication following nephrectomy that results in an anephric state. Targeting a preoperative potassium < 3.85 mEq/L may decrease intraoperative and postoperative hyperkalemia.