Search

Background: Studies in adults have shown that persistent kidney dysfunction ≥7–90 days following acute kidney injury (AKI), termed acute kidney disease (AKD), increases chronic kidney disease (CKD) and mortality risk. Little is known about the factors associated with the transition of AKI to AKD and the impact of AKD on outcomes in children. The aim of this study is to evaluate risk factors for progression of AKI to AKD in hospitalized children and to determine if AKD is a risk factor for CKD. Methods: Retrospective cohort study of children age ≤18 years admitted with AKI to all pediatric units at a single tertiary-care children's hospital between 2015 and 2019. Exclusion criteria included insufficient serum creatinine values to evaluate for AKD, chronic dialysis, or previous kidney transplant. Results: A total of 528 children with AKI were included in the study. There were 297 (56.3%) hospitalized AKI survivors who developed AKD. Among children with AKD, 45.5% developed CKD compared to 18.7% in the group without AKD (OR 4.0, 95% CI 2.1–7.4, p-value <0.001 using multivariable logistic regression analysis including other covariates). Multivariable logistic regression model identified age at AKI diagnosis, PCICU and NICU admission, prematurity, malignancy, bone marrow transplant, previous AKI, mechanical ventilation, AKI stage, duration of kidney injury, and need for kidney replacement therapy during day 1–7 as risk factors for AKD after AKI. Conclusions: AKD is common among hospitalized children with AKI and multiple risk factors are associated with AKD. Children that progress from AKI to AKD are at higher risk of developing CKD. [ABSTRACT FROM AUTHOR]

Steroid-resistant nephrotic syndrome (SRNS) is the most severe form of childhood nephrotic syndrome with an increased risk of progression to chronic kidney disease stage 5. Research endeavors to date have identified more than 80 genes that are associated with SRNS. Most of these genes regulate the structure and function of the podocyte, the visceral epithelial cells of the glomerulus. Although individuals of African ancestry have the highest prevalence of SRNS, especially those from Sub-Saharan Africa (SSA), with rates as high as 30–40% of all cases of nephrotic syndrome, studies focusing on the characterization and understanding of the genetic basis of SRNS in the region are negligible compared with Europe and North America. Therefore, it remains unclear if some of the variants in SRNS genes that are deemed pathogenic for SRNS are truly disease causing, and if the leading causes of monogenic nephrotic syndrome in other populations are the same for children in SSA with SRNS. Other implications of this lack of genetic data for SRNS in the region include the exclusion of children from the region from clinical trials aimed at identifying potential novel therapeutic agents for this severe form of nephrotic syndrome. This review underlines a need for concerted efforts to advance the genetic basis of SRNS in children in SSA. Such endeavors will complement global efforts at understanding the genetic basis of nephrotic syndrome. [ABSTRACT FROM AUTHOR]

APOL1 risk variants are associated with an increased risk of chronic kidney disease. Findings from a new study demonstrate that a small molecule, inaxaplin, inhibits APOL1 channel function; furthermore, inaxaplin reduced proteinuria in patients with focal segmental glomerulosclerosis and two APOL1 risk variants. [ABSTRACT FROM AUTHOR]

Advances in kidney genomics in the past 20 years has opened the door for more precise diagnosis of kidney disease and identification of new and specific therapeutic agents. Despite these advances, an imbalance exists between low-resource and affluent regions of the world. Individuals of European ancestry from the United States, United Kingdom, and Iceland account for 16% of the world's population, but represent more than 80% of all genome-wide association studies. South Asia, Southeast Asia, Latin America, and Africa together account for 57% of the world population but less than 5% of genome-wide association studies. Implications of this difference include limitations in new variant discovery, inaccurate interpretation of the effect of genetic variants in non-European populations, and unequal access to genomic testing and novel therapies in resource-poor regions. It also further introduces ethical, legal, and social pitfalls, and ultimately may propagate global health inequities. Ongoing efforts to reduce the imbalance in low-resource regions include funding and capacity building, population-based genome sequencing, population-based genome registries, and genetic research networks. More funding, training, and capacity building for infrastructure and expertise is needed in resource-poor regions. Focusing on this will ensure multiple-fold returns on investments in genomic research and technology. [Display omitted] [ABSTRACT FROM AUTHOR]

Background and objectives: Chronic kidney disease is a persistent chronic health condition commonly seen in pediatric nephrology programs. Our study aims to evaluate the sensitivity of the Patient Reported Outcomes Measurement Information System (PROMIS) pediatric instrument to indicators of disease severity and activity in pediatric chronic kidney disease. Methods: This cross sectional study included 233 children 8-17 years old, with chronic kidney disease from 16 participating institutions in North America. Disease activity indicators, including hospitalization in the previous 6 months, edema, and number of medications consumed daily, as well as disease severity indicators of kidney function and coexisting medical conditions were captured. PROMIS domains, including depression, anxiety, social-peer relationships, pain interference, fatigue, mobility, and upper extremity function, were administered via web-based questionnaires. Absolute effect sizes (AES) were generated to demonstrate the impact of disease on domain scores. Four children were excluded because of missing glomerular filtration rate (GFR) estimations. Results: Of the 229 children included in the final analysis, 221 completed the entire PROMIS questionnaire. Unadjusted PROMIS domains were responsive to chronic kidney disease activity indicators and number of coexisting conditions. PROMIS domain scores were worse in the presence of recent hospitalizations (depression AES 0.33, anxiety AES 0.42, pain interference AES 0.46, fatigue AES 0.50, mobility AES 0.49), edema (depression AES 0.50, anxiety AES 0.60, pain interference AES 0.77, mobility AES 0.54) and coexisting medical conditions (social peer-relationships AES 0.66, fatigue AES 0.83, mobility AES 0.60, upper extremity function AES 0.48). Conclusions: The PROMIS pediatric domains of depression, anxiety, social-peer relationships, pain interference, and mobility were sensitive to the clinical status of children with chronic kidney disease in this multi-center cross sectional study. We demonstrated that a number of important clinical characteristics including recent history of hospitalization and edema, affected patient perceptions of depression, anxiety, pain interference, fatigue and mobility. The PROMIS instruments provide a potentially valuable tool to study the impact of chronic kidney disease. Additional studies will be required to assess responsiveness in PROMIS score with changes in disease status over time. [ABSTRACT FROM AUTHOR]

Background: Idiopathic nephrotic syndrome (NS) in children is classified as steroid sensitive or steroid resistant. Steroid sensitivity typically portends a low risk of permanent renal failure. However, some initially steroid-sensitive patients later develop steroid resistance. These patients with late steroid resistance (LSR) are often treated with immunosuppressant medications, but the effect of these additional drugs on the long-term prognosis of LSR is still unknown. Methods: A retrospective chart review was performed on patients diagnosed with idiopathic NS and subsequent LSR during the 8-year study period from 2002 up to and including 2009, with a minimum of 2 years of follow-up. Primary outcome measures were proteinuria and renal function. Results: A total of 29 patients were classified as having LSRNS. The majority of patients received treatment with calcineurin inhibitors and/or mycophenolate mofetil. Seven patients received three or more non-steroid immunosuppressant medications. Sustained complete or partial remission was achieved in 69 % of patients. Three developed end-stage renal disease, and all others maintained normal renal function. There were 13 episodes of serious adverse events, none of which were fatal or irreversible. Conclusion: Most patients with LSRNS responded to immunosuppressive therapy by reduction or resolution of proteinuria and preservation of renal function. The results suggest that immunosuppressive treatment is a viable option in NS patients who develop LSR. [ABSTRACT FROM AUTHOR]

Focal and segmental glomerulosclerosis (FSGS) is a major cause of end-stage kidney disease. Recent advances in molecular genetics show that defects in the podocyte play a major role in its pathogenesis and mutations in inverted formin 2 (INF2) cause autosomal dominant FSGS. In order to delineate the role of INF2 mutations in familial and sporadic FSGS, we sought to identify variants in a large cohort of patients with FSGS. A secondary objective was to define an approach for genetic screening in families with autosomal dominant disease. A total of 248 individuals were identified with FSGS, of whom 31 had idiopathic disease. The remaining patients clustered into 64 families encompassing 15 from autosomal recessive and 49 from autosomal dominant kindreds. There were missense mutations in 8 of the 49 families with autosomal dominant disease. Three of the detected variants were novel and all mutations were confined to exon 4 of INF2, a regulatory region responsible for 90% of all changes reported in FSGS due to INF2 mutations. Thus, in our series, INF2 mutations were responsible for 16% of all cases of autosomal dominant FSGS, with these mutations clustered in exon 4. Hence, screening for these mutations may represent a rapid, non-invasive and cost-effective method for the diagnosis of autosomal dominant FSGS. [ABSTRACT FROM AUTHOR]

Focal and segmental glomerulosclerosis (FSGS) is the most common glomerular cause of end-stage kidney disease (ESKD). Although the etiology of FSGS has not been fully elucidated, recent results from the positional cloning of genes mutated in nephrotic syndromes are now beginning to provide insight into the pathogenesis of these diseases. Mutations in PLCE1/NPHS3 have recently been reported as a cause of nephrotic syndrome characterized by diffuse mesangial sclerosis (DMS) histology. One single family with a missense mutation had late onset of the disease that was characterized by FSGS. To further define the role of PLCE1 mutations in the etiology of FSGS, we performed mutational analysis in 69 families with FSGS. A total of 69 families with 231 affected individuals were examined. The median age of disease onset was 26 years (range 1–66 years). Onset of ESKD was at a median age of 35.5 years. Seven variants leading to non-synonymous changes were found, of which only two are new variants (exon 4 c.1682 G>A R561Q, exon 31 c.6518A>G K2173R). No known disease-causing mutations were identified in the families screened. PLCE1/NPHS3 mutations are not a cause of FSGS in this cohort. The absence of mutations in PLCE1/NPHS3 in this study indicates that there are additional genetic causes of FSGS and that hereditary FSGS is a heterogeneous disease. Kindreds appropriate for genome-wide screening are currently being subjected to analysis with the aim of identifying other genetic causes of FSGS. [ABSTRACT FROM AUTHOR]

Increased vascular stiffness is an established risk marker of cardiovascular diseases (CVD) in adults with end-stage renal disease, but its role in pediatric patients remains to be defined. We prospectively examined arterial compliances of adolescents and young adults on hemodialysis (HD) using diastolic pulse wave analysis (DPWA). Each of the ten HD patients (age 17.3 ± 3.9 years; mean ± SD) had two DPWA tests within a three-week time period. DPWA measurement was performed before and hourly until the end of three-hour HD. Pre-HD large artery elasticity index (LAEI) was reduced in one patient and small artery elasticity index (SAEI) was reduced in another. Neither patient was hypertensive. Eight other patients had a reduction in both LAEI and SAEI. Among them, six patients had systolic and/or diastolic hypertension, and the other two were normotensive. Serum phosphorus correlated positively with stroke volume and cardiac output indices and negatively with SAEI. The reduction in BP during HD correlated with the amount of fluid removal. LAEI and SAEI were unchanged during HD. In conclusion, the reduction in LAEI and/or SAEI was observed in four normotensive patients, suggesting hypertension was not the only contributing factor for the reduced arterial compliances in our patients. The association between SAEI and serum phosphorus suggests that SAEI derived from DPWA can potentially be an early non-invasive, operator-independent, and volume-independent marker of CVD in adolescents and young adults receiving HD. Longitudinal studies with a larger sample size are needed to confirm our observation and speculation. [ABSTRACT FROM AUTHOR]