Age at onset and neurologic features were important for outcome prediction in ATM. Steroid therapy did not associate with better outcome.

Background DNA methylation of gene promoters is associated with transcriptional inactivation. Changes in DNA methylation can lead to differences in gene expression levels and thereby influence disease development. We hypothesized that epigenetics underlies the pathogenesis of minimal change nephrotic syndrome (MCNS). Methods Genome-wide DNA methylation changes between relapse and remission in monocytes (n06) and naive T helper cells (Th0s) (n04) isolated from patients with MCNS were investigated using the microarray-based integrated analysis of methylation by isochizomers (MIAMI) method. We confirmed the MIAMI results using bisulfite-pyrosequencing analysis. Expression analysis was performed using quantitative real-time PCR. Results Three gene loci (GATA2, PBX4, and NYX) were significantly less methylated in Th0s during relapse than in remission, compared to none in monocytes. In addition, the distance distribution from the regression line of all probes in MIAMI was significantly different between monocytes and Th0s. The mRNA levels of the three genes in Th0s were not significantly different between relapse and remission. Conclusions Our results demonstrate that the change in DNA methylation patterns from remission to relapse in MCNS occurs predominantly in Th0s rather than in monocytes and suggest that epigenetic regulation in Th0s underlies the pathogenesis of MCNS.

Minimal change nephrotic syndrome (MCNS) in children is frequently associated with allergy and immunoglobulin E production. T helper subtype 2 cytokines, such as interleukin (IL)-4 and IL-13, may have an important role in the development of atopy. We investigated the association of genetic variations of IL-4 receptor alpha chain (IL-4Ralpha), IL-13 and signal transducer and activator of transcription 6 (STAT6) genes with MCNS. We analyzed these polymorphisms in 85 Japanese children (55 males, 30 females) with MCNS and 127 healthy controls with neither allergic nor renal diseases. Genomic DNA was extracted from peripheral blood leukocytes. The single nucleotide polymorphisms of IL-4Ralpha (Ile50Val) and IL-13 (R130Q) were detected by primer-specific polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism analysis, respectively. GT repeat polymorphism in STAT6 gene exon 1 was investigated by fragment length analysis. A significant difference in allelic frequencies in the STAT6 gene was detected between the MCNS and control groups. There was no significant difference between the two groups for genetic variations of IL-4Ralpha and IL-13 genes. We found a significant difference in IL-4Ralpha gene polymorphism between MCNS subgroups divided according to the number of relapses. These results suggested that the genetic variation in the first exon of the STAT6 gene may be associated with a predisposition to MCNS and that the genetic variation in the IL-4Ralpha gene may be associated with its clinical course.

Congenital nephrotic syndrome of the Finnish type (CNF) is a rare autosomal recessive disorder. The incidence of CNF is relatively high in Finland but considerably lower in other countries. We encountered a male newborn with CNF, associated with compound heterozygous mutations in nephrosis 1, congenital, Finnish type (NPHS1). The patient was admitted to hospital as a preterm infant. Physical and laboratory findings fulfilled the diagnostic criteria of nephrotic syndrome, and were compatible with a diagnosis of CNF, but there was no family history of the disease. On genetic analysis of NPHS1 a paternally derived heterozygous frame-shift mutation caused by an 8 bp deletion, resulting in a stop codon in exon 16 (c.2156-2163 delTGCACTGC causing p.L719DfsX4), and a novel, maternally derived nonsense mutation in exon 15 (c.1978G>T causing p.E660X) were identified. Early genetic diagnosis of CNF is important for proper clinical management and appropriate genetic counseling.

Joubert syndrome (JS) is an inherited ciliopathy characterized by a distinctive cerebellar and brain stem malformation which is known as the “molar tooth sign” on axial brain images, hypotonia, and developmental delay. Approximately 25–30% of patients with JS have kidney disease and many of them progress to end-stage kidney disease (ESKD). However, there are few reports on the outcomes of renal replacement therapy (RRT) in patients with JS and ESKD. In this study, we clarified the clinical features, treatment, and outcomes of patients with JS who underwent RRT. We retrospectively analyzed the medical records and clinical characteristics of 11 patients with JS who underwent RRT between June 1994 and July 2019. Data are shown as the median (range). Gene analysis was performed in 8 of the 11 cases, and CEP290 mutations were found in four patients, two had TMEM67 mutations, one had a RPGRIP1L mutation, and one patient showed no mutation with the panel exome analysis. Complications in other organs included hydrocephalus in two cases, retinal degeneration in eight cases, coloboma in one case, liver diseases in four cases, and polydactyly in one case. Peritoneal dialysis (PD) was introduced in seven cases, with a median treatment duration of 5.4 (3.4–10.7) years. Hemodialysis was performed using arteriovenous fistula in two cases, and kidney transplantation was performed 9 times in eight cases. Only one of the grafts failed during the observation period of 25.6 (8.2–134.2) months. The glomerular filtration rate at the final observation was 78.1 (41.4–107.7) mL/min/1.73 m2. The median age at the final observation was 13.4 (5.6–25.1) years, and all patients were alive except one who died of hepatic failure while on PD. Any type of RRT modality can be a treatment option for patients with JS and ESKD.