HNF1B mutations, one of the most common causes of congenital anomalies of the kidney and urinary tract, manifest as various renal and extrarenal phenotypes. We analyzed the genotype-phenotype correlations in 14 pediatric patients with HNF1B mutations. Genetic studies revealed total gene deletion in six patients (43%). All patients had bilateral renal abnormalities, primarily multiple renal cysts. Twelve patients exhibited progressive renal functional deterioration, and six of them progressed to kidney failure. The annual reduction in estimated glomerular filtration rate was−2.1 mL/min/1.73 m². Diabetes developed in five patients (36%), including one patient with new-onset diabetes after transplantation. Neurological deficits were noted in three patients (21%), one with total gene deletion and two with missense mutations. Pancreatic abnormalities were more frequent in patients with missense mutations than in patients with other types of mutations. Genotype showed no significant correlation with renal outcomes or other extrarenal manifestations. The HNF1B scores at the times of onset and genetic diagnosis were <8 in two patients and one patient, respectively. Diagnosis of HNF1B mutations is clinically difficult because of extreme phenotypic variability and incomplete penetrance. Furthermore, some phenotypes develop with age. Therefore, patient age should be taken into consideration to increase the diagnostic rate, because some phenotypes develop with age.

Kim MY, et al. J Korean Med Sci. 2018 Dec;34(1):e4. https://doi.org/10.3346/jkms.2019.34.e4

With an increasing aging population, the mean age of patients with end-stage kidney disease (ESKD) is globally increasing. However, the current clinical status of elderly patients undergoing hemodialysis (HD) is rarely reported in Korea. The current study analyzed the clinical features and trends of older patients undergoing HD from the Korean Renal Data System (KORDS) database. The patients were divided into three groups according to age: <65 years (the young group), n = 50,591 (35.9%); 65–74 years (the younger-old group), n = 37,525 (26.6%); and ≥75 years (the older-old group), n = 52,856 (37.5%). The proportion of older-old group undergoing HD significantly increased in incidence and decreased in prevalence from 2013 to 2022. The median levels of hemoglobin, serum creatinine, albumin, calcium, phosphorus, and intact parathyroid hormone significantly decreased in the older-old group. The proportions of arteriovenous fistula creation and left forearm placement showed decreased trends with age. Although the utilization of low surface area dialyzers increased with age, the dialysis adequacy, including urea reduction ratio and Kt/V was within acceptable range in the older-old group on HD. Over the past 20 years, the mortality rate in the older-old group has increased, with cardiovascular diseases decreasing and infectious diseases increasing. The incidence of elderly patients undergoing HD has increased over time, but the high mortality of the older-old group needs to be solved. Therefore, it is imperative to develop holistic strategies based on age and individual needs for patients with ESKD.

Kang S, et al. J Korean Med Sci. 2019 Jun;34(24):e173. https://doi.org/10.3346/jkms.2019.34.e173

Korean Renal Data System (KORDS) is a nationwide end-stage renal disease (ESRD) registry database operated by the Korean Society of Nephrology (KSN). Diabetes mellitus is currently the leading cause of ESRD in Korea; this article provides an update on the trends and characteristics of diabetic ESRD patients. The KORDS Committee of KSN collects data on dialysis centers and patients through an online registry program. Here, we analyzed the status and trends in characteristics of diabetic chronic kidney disease stage 5D (CKD 5D) patients using data from 2001 to 2021. In 2021, the dialysis adequacy of hemodialysis (HD) was lower in diabetic CKD 5D patients than in nondiabetic CKD 5D patients, while that of peritoneal dialysis (PD) was similar. Diabetic CKD 5D patients had a higher proportion of cardiac and vascular diseases and were more frequently admitted to hospitals than nondiabetic CKD 5D patients, and the leading cause of death was cardiac disease. From 2001 to 2020, diabetic CKD 5D patients had a higher mortality rate than nondiabetic CKD 5D patients, but in 2021 this trend was reversed. Diabetic PD patients had the highest mortality rate over 20 years. The mortality rate of diabetic HD patients was higher than that of nondiabetic HD patients until 2019 but became lower starting in 2020. There was a decreasing trend in mortality rate in diabetic CKD 5D patients, but cardiac and vascular diseases were still prevalent in diabetic CKD 5D patients with frequent admissions to hospitals. More specialized care is needed to improve the clinical outcomes of diabetic CKD 5D patients.

Background: This study investigated the clinical characteristics and kidney outcomes of childhood-onset lupus nephritis (LN), and risk factors associated with prognosis. Methods: We enrolled 216 patients with histologically diagnosed LN during childhood. The Korean Society of Pediatric Nephrology organized a retrospective cohort study of childhood-onset LN in 13 major pediatric nephrology centers in South Korea. Results: The mean age at kidney biopsy was 13.2 ± 3.22 years. The main forms of presentation were nephrotic syndrome and/or hematuria in 152 patients (70.4%), and the most common histological finding was World Health Organization (WHO) class IV in 138 patients (63.9%), followed by WHO class III in 34 patients (15.7%). In the outcome analysis, the mean follow-up period of the patients was 7.8 ± 5.11 years. At last follow-up, 32 patients (14.8%) developed advanced chronic kidney disease (CKD). Male sex and failure to achieve remission at 12 months of treatment were significant risk factors for developing advanced CKD (hazard ratio of 2.57 and 2.29, respectively). Conclusion: Our study demonstrated the clinical characteristics and long-term outcomes of patients with childhood-onset LN. Male sex and failure to achieve remission in the first year of treatment were predictive of advanced CKD. Therefore, prompt awareness and close monitoring of these high-risk patients are needed, which may further improve the prognosis of children with LN.