. Congenital adrenal hyperplasia is a category of disorders characterized by impaired adrenocortical steroidogenesis. The most frequent disorder of congenital adrenal hyperplasia is 21-hydroxylase deficiency, which is caused by pathogenic variants of CAY21A2 and is prevalent between 1 in 18,000 and 20,000 in Japan. The clinical guidelines for 21-hydroxylase deficiency in Japan have been revised twice since a diagnostic handbook in Japan was published in 1989. On behalf of the Japanese Society for Pediatric Endocrinology, the Japanese Society for Mass Screening, the Japanese Society for Urology, and the Japan Endocrine Society, the working committee updated the guidelines for the diagnosis and treatment of 21-hydroxylase deficiency published in 2014, based on recent evidence and knowledge related to this disorder. The recommendations in the updated guidelines can be applied in clinical practice considering the risks and benefits to each patient.

Hypophosphatasia is a rare inherited disorder caused by deficient tissue-nonspecific alkaline phosphatase activity. It is classified into 6 subtypes, and the perinatal lethal form of hypophosphatasia is the most severe. Patients with this form suffer from various symptoms, including respiratory failure, premature craniosynostosis, rachitic changes in the metaphyses, convulsions and hypercalcemia. This report presents 6 cases of the perinatal lethal form of hypophosphatasia. All of the patients showed shortening of the long bones in utero in ultrasonographic examinations. Two of the six patients died at birth because they could not establish spontaneous breathing. Three of the remaining four patients also died before 1 yr of age. The major cause of death was respiratory failure due to hypoplastic lung. All of the patients, except for the two who died at birth, experienced convulsions in their clinical courses. Vitamin B6 therapy effectively reduced the frequency and severity of convulsions. However, it could not always make the patients convulsion free. Three patients underwent a genetic analysis. The 1559delT mutation, which abolishes Alkaline Phosphatase (ALP) activity, was a hot spot. A homozygous 1559delT mutation was observed in two patients. However, they differed in severity of symptoms. Although a good genotype-phenotype correlation has been reported in hypophosphatasia, the genotype alone does not always predict the life span of the patients. These cases therefore suggested the importance of genetic counseling.

Objective We recently reported cases of adipsic hypernatremia caused by autoantibodies against the subfornical organ in patients with hypothalamic‐pituitary lesions. This study aimed to clarify the clinical features of newly identified patients with adipsic hypernatremia whose sera displayed immunoreactivity to the mouse subfornical organ. Design Observational cohort study of patients diagnosed with adipsic hypernatremia in Japan, United States, and Europe. Methods The study included 22 patients with adipsic hypernatremia but without overt structural changes in the hypothalamic‐pituitary region and congenital disease. Antibody response to the mouse subfornical organ was determined using immunohistochemistry. The clinical characteristics were compared between the patients with positive and negative antibody responses. Results Antibody response to the mouse subfornical organ was detected in the sera of 16 patients (72.7%, female/male ratio, 1:1, 12 pediatric and 4 adult patients). The prolactin levels at the time of diagnosis were significantly higher in patients with positive subfornical organ (SFO) immunoreactivity than in those with negative SFO immunoreactivity (58.9 ± 33.5 vs. 22.9 ± 13.9 ng/ml, p < .05). Hypothalamic disorders were found in 37.5% of the patients with positive SFO immunoreactivity. Moreover, six patients were diagnosed with rapid‐onset obesity with hypothalamic dysfunction, hypoventilation, and autonomic dysregulation/neural tumor syndrome after the diagnosis of adipsic hypernatremia. Plasma renin activity levels were significantly higher in patients with serum immunoreactivity to the Nax channel. Conclusions The patients with serum immunoreactivity to the SFO had higher prolactin levels and hypothalamic disorders compared to those without the immunoreactivity. The clinical characteristics of patients with serum immunoreactivity to the subfornical organ included higher prolactin levels and hypothalamic disorders, which were frequently associated with central hypothyroidism and the presence of retroperitoneal tumors.

Cytochrome P450 oxidoreductase deficiency (PORD) is a disorder of steroidogenesis that causes various symptoms such as skeletal malformations, disorders of sex development, and adrenal insufficiency. The aim of this study was to elucidate the clinical characteristics, especially age at diagnosis and treatment, of PORD from the perinatal period to adulthood in Japan. The first questionnaire was sent to 183 council members of the Japanese Society for Pediatric Endocrinology on 1 September 2018. The response rate was 65%, and a total of 39 patients with PORD were examined at 20 hospitals. The second questionnaire was sent in November 2018 to the council members examining these 39 patients with PORD. The response rate was 77%, and we received clinical information on 30 of the 39 patients. The two novel clinical findings were the age at diagnosis and the treatment of Japanese patients with PORD. In many cases, PORD can be diagnosed at <3 months of age. Hydrocortisone as the primary treatment during infancy can be used daily or in stressful situations; however, because patients with PORD generally have mild to moderate adrenal insufficiency, some might be able to avoid hydrocortisone treatment. Patients with PORD should be carefully followed up, and treatment should be optimized as for patients with other types of adrenal insufficiency. Other characteristics in the present study were similar to those described in previous reports.