Analysis of the ratio of urinary beta-2-microglobulin to total protein concentration in children with isolated tubulointerstitial disease.

Background: Proteinuria is broadly classified into glomerular and tubular proteinuria. Urinary beta-2-microglobulin (β2-MG) is known as a marker for detecting tubulointerstitial diseases. However, tubulointerstitial damage can also lead to an increase in urinary β2-MG level in some patients with glomerular diseases.

An infant case of pseudohypoaldosteronism type1A caused by a novel NR3C2 variant.

Pseudohypoaldosteronism type1A (PHA1A) is the renal form of pseudohypoaldosteronism with autosomal dominant inheritance. PHA1A is caused by haploinsufficiency of the mineralocorticoid receptor, which is encoded by NR3C2. We encountered an infant who was diagnosed with PHA1A due to hyponatremia, hyperkalemia, and poor weight gain in the neonatal period.

A case with neonatal hyperinsulinemic hypoglycemia: It is a characteristic complication of Sotos syndrome.

Sotos syndrome (SoS, OMIM #117550) is an overgrowth syndrome. Deletions or intragenic mutations of the NSD1 , which is located at chromosome 5q35, are responsible for more than 75% of SoS. Conventionally, neonatal hypoglycemia was reported briefly as one of the infrequent symptoms of SoS.

Clinical characterization and identification of duplication breakpoints in a Japanese family with Xq28 duplication syndrome including MECP2.

Xq28 duplication syndrome including MECP2 is a neurodevelopmental disorder characterized by axial hypotonia at infancy, severe intellectual disability, developmental delay, mild characteristic facial appearance, epilepsy, regression, and recurrent infections in males. We identified a Japanese family of Xq28 duplications, in which the patients presented with cerebellar ataxia, severe constipation, and small feet, in addition to the common clinical features. The 488-kb duplication spanned from L1CAM to EMD and contained 17 genes, two pseudo genes, and three microRNA-coding genes.

Methylxanthines inhibit late-onset circulatory collapse in preterm infants.

Background: Several drugs, when used chronically in very preterm infants, are considered to be associated with the development of late-onset circulatory collapse (LCC), which can lead to neurodevelopmental impairment. Despite its clinical importance, conclusive risk factors for LCC have yet to be identified. The aim of the present study was to investigate the relationship between LCC and diuretics, methylxanthines, levothyroxine, and sodium chloride.

Prevalence of hepatitis E virus infection in Japanese children.

Background: Recently, sporadic cases of acute hepatitis and fulminant hepatitis caused by hepatitis E virus (HEV) have been reported in Japan. However, few reports have addressed the issue of HEV infection during childhood.

Methods: This study included 5 patients with fulminant hepatitis, 30 patients with acute hepatitis, and 309 patients without history of hepatic dysfunction or hepatitis in childhood as control.