Kidney-resident macrophages limit toxin-induced inflammation through their hallmark functions.

Introduction: The inflammatory phenotype of acute kidney injury (AKI), characterized by interstitial infiltration of immune cells, arises due to nephrotoxic agents. However, it does not pose the same risk of occurrence and progression for everyone, suggesting that the amplification or attenuation of disease depends on the unique immunological status of each kidney. Here, our study investigated the regulatory role of kidney-resident macrophages (KRMs) in the induction and progression of toxin-induced AKI.

Impact of early life antibiotic exposure on the preschool developmental status: a nationwide population-based study.

Objective: Growing concerns exist about the potential adverse effects of early antibiotic exposure on neurodevelopmental outcomes. However, large-scale studies exploring these implications in early childhood are rare.

Design: A nationwide, population-based retrospective cohort study using data from the Korean National Health Insurance System and the National Health Screening Program for Infants and Children (NHSPIC) between 2015 and 2022.

Evaluation of acute kidney injury in preterm infants using serum creatinine decline in comparison with KDIGO criteria.

Background: Acute kidney injury (AKI) is commonly observed in critically ill neonates; however, early identification of AKI in the first week of life is challenging due to the influence of maternal serum creatinine (SCr). An alternative criterion proposed by Gupta et al. based on SCr decline may identify additional infants at risk beyond the KDIGO definition.

Trends in antibiotic resistance of urinary tract infections in young children, 2010-2023.

Background: Urinary tract infections (UTI) are the leading cause of severe bacterial infection in children under 24 months. Increasing antimicrobial resistance, particularly to third-generation cephalosporins, is a growing concern. This study examines recent resistance trends in young children with UTI in Korea.

Persistent hyperparathyroidism after kidney transplantation in children.

Background: Persistent hyperparathyroidism after kidney transplantation (KT) has been reported in up to 50% of adult recipients, but pediatric data remain limited. We evaluated the prevalence, skeletal manifestations, and risk factors for persistent hyperparathyroidism in children following KT.

Methods: In this retrospective cohort study, 107 pediatric KT recipients (58% male; median age 10.

External validation of the international immunoglobulin A nephropathy (IgAN) prediction tool in Korean children with IgAN.

Background: The International IgA nephropathy (IgAN) Prediction Tool was recently updated to predict the risk of a 30% decline in estimated glomerular filtration rate (eGFR) or kidney failure in children with IgAN. We aimed to evaluate the clinical performance of this tool in a Korean cohort of children with IgAN.

Methods: We calculated the predicted risk for biopsy-proven IgAN children from 20 Korean centers.

Long-term kidney outcomes in patients with Kabuki syndrome.

Background: This study assessed the clinical features, prevalence of kidney and urinary manifestations, and progression of chronic kidney disease (CKD) in patients with Kabuki syndrome (KS).

Methods: This retrospective cohort study enrolled patients with KS who visited a single tertiary center from 2003 to 2023.

Results: Sixty-five patients (28 boys) were diagnosed with KS at a median age of 2.

Intrarenal reflux is linked to subsequent kidney scarring: a retrospective study.

Background: This study investigates whether intrarenal reflux (pyelotubular backflow) is associated with kidney scarring in children with urinary tract infection (UTI).

Methods: We retrospectively reviewed 441 children diagnosed with UTI who underwent voiding cystourethrography (VCUG) and a technetium-99 m dimercaptosuccinic acid (DMSA) scan more than 3 months after the UTI. Intrarenal reflux was identified on VCUG.

Inflammatory Milieu by Crosstalk between Glomerulus and Proximal Tubular Cells in Type 2 Diabetes Mellitus Kidney Disease.

Background: Due to the limited availability of therapeutic agents for type 2 diabetic kidney disease (T2DKD), there is a need for further knowledge derived from experimental models and innovative techniques. In addressing this issue, single-cell RNA sequencing (scRNA-seq) has been exclusively applied to a genetically modified diabetic kidney disease model, but not to an induced model representing T2DKD. Herein, we analyzed scRNA-seq and other experiments from an induced T2DKD model and validated the results in human-derived biospecimens.

Single-cell transcriptomics in a child with coenzyme Q10 nephropathy: potential of single-cell RNA sequencing in pediatric kidney disease.

Background: Coenzyme Q10 (CoQ10) nephropathy is a well-known cause of hereditary steroid-resistant nephrotic syndrome, primarily impacting podocytes. This study aimed to elucidate variations in individual cell-level gene expression in CoQ10 nephropathy using single-cell transcriptomics.

Methods: We conducted single-cell sequencing of a kidney biopsy specimen from a 5-year-old boy diagnosed with a CoQ10 nephropathy caused by a compound heterozygous COQ2 mutation complicated with immune complex-mediated glomerulonephritis.

Association between Exclusive Breastfeeding and the Incidence of Childhood Nephrotic Syndrome.

Objective: To assess the relationship between breastfeeding and the risk of developing nephrotic syndrome using a population-based nationwide birth cohort in Korea.

Study Design: This nationwide cohort study utilized data from the National Health Information Database and the National Health Screening Program for Infants and Children. The study included all children born between January 1, 2010, and December 31, 2018, who underwent their first health screening, which included a specific questionnaire on breastfeeding between 4 and 6 months of age.

Decreased incidence of peritoneal dialysis-associated peritonitis in young children.

Aim: Peritonitis is the most common complication of peritoneal dialysis (PD). This study aimed to investigate changes in the incidence, risk factors, microbiology, and clinical outcomes of PD-associated peritonitis in the past decades.

Methods: This was a retrospective study that included children who initiated chronic PD at our institution between 2000 and 2017.

Increasing trend in hypertension prevalence among Korean adolescents from 2007 to 2020.

Background: The purpose of this study was to examine the prevalence of hypertension in Korean adolescents, its long-term trends, and factors associated with the development of hypertension.

Methods: Data of the Korea National Health and Nutrition Examination Survey (KNHANES) from 2007 to 2020 were combined into three time periods (2007-2011, 2012-2016, and 2017-2020). A total of 11,146 Korean adolescents aged 10-18 were included in the analysis.

Effects of urinary tract infection during the first years of life in subsequent growth: a nationwide comparative matched cohort study.

Background: Although various childhood illnesses are known to influence growth status, the impact of urinary tract infections (UTI) on subsequent childhood growth remains unclear. This study was conducted to examine the association between UTI during infancy and growth status at 30-36 months.

Methods: Nationwide population-based matched cohort study was done using data from the Korean National Health Insurance System (NHIS) and the Korean National Health Screening Program for Infants and Children (NHSPIC) between January 2018 and December 2020.

Baseline characteristics of participants enrolled in the KoreaN cohort study for Outcomes in patients With Pediatric Chronic Kidney Disease (KNOW-Ped CKD).

Background: We developed the KoreaN cohort study for Outcomes in patients With Pediatric Chronic Kidney Disease (KNOW-Ped CKD) as a subcohort of KNOW-CKD to investigate the different characteristics of pediatric CKD between countries and races.

Methods: Children aged younger than 18 years with stage 1 ~ 5 CKD were recruited at seven major pediatric nephrology centers in Korea. Blood and urine samples, as well as demographic and clinical data, were collected.

Clinical Relevance of Fluid Volume Status Assessment by Bioimpedance Spectroscopy in Children Receiving Maintenance Hemodialysis or Peritoneal Dialysis.

Bioimpedance spectroscopy (BIS) is a noninvasive method used to evaluate body fluid volume status in dialysis patients, but reports on its effectiveness in pediatrics are scarce. We investigated the correlation between BIS and clinical characteristics and identified the changes in patients whose dialysis prescription was modified based on BIS. The medical records of children on maintenance dialysis who had undergone BIS between 2017 and 2019 were reviewed.

Out-of-Hospital Cohort Treatment of Coronavirus Disease 2019 Patients with Mild Symptoms in Korea: an Experience from a Single Community Treatment Center.

The outbreak of Coronavirus Disease 2019 (COVID-19) caused a worldwide pandemic. Less than 6 weeks after the first confirmed cases in Korea, the patient number exceeded 5,000, which overcrowded limited hospital resources and forced confirmed patients to stay at home. To allocate medical resources efficiently, Korea implemented a novel institution for the purpose of treating patients with cohort isolation out of hospital, namely the Community Treatment Center (CTC).

Acute kidney injury predicts all-cause mortality in patients with cancer.

Background: Acute kidney injury (AKI) is a critical issue in cancer patients because it is not only a morbid complication but also able to interrupt timely diagnostic evaluation or planned optimal treatment. However, the impact of AKI on overall mortality in cancer patients remains unclear.

Methods: We conducted a retrospective cohort study of 67 986 cancer patients, from 2004 to 2013 to evaluate the relationship between AKI and all-cause mortality.

Acute Kidney Injury in Pediatric Cancer Patients.

Objective: To analyze the incidence of acute kidney injury (AKI) in the first year after cancer diagnosis in children and to evaluate the short-term and long-term effects on renal function and proteinuria.

Study Design: Retrospective review of medical records was done on children who were diagnosed and treated for cancer at Seoul National University Hospital between 2004 and 2013. AKI was defined according to the Kidney Disease: Improving Global Outcomes criteria.

Three cases of multicentric carpotarsal osteolysis syndrome: a case series.

Background: Multicentric carpotarsal osteolysis syndrome (MCTO) is characterized by progressive destruction and disappearance of the carpal and tarsal bones associated with nephropathy. MCTO is caused by loss-of-function mutations in the MAF bZIP transcription factor B (MAFB) gene.

Case Presentation: This report describes three unrelated patients with MAFB mutations, including two male and one female patient.