Atrophic autoimmune thyroiditis (AAT) is a type of autoimmune hypothyroidism without goiter. TSH receptor-blocking antibodies (TSBAb) are involved in its etiology in adults. Reportedly, this disease is extremely rare in children. In this study, we aimed to investigate the prevalence of TSBAb during AAT onset in children using a commercially available cell-based bioassay TSAb kit. We conducted a multicenter retrospective observational study. We collected data of patients with AAT who were < 15 yr old, enrolled in a collaborative research group, and diagnosed since July 2003. AAT was defined as acquired autoimmune hypothyroidism without thyroid enlargement. Eighteen patients (including 15 females) whose TSH receptor antibody (TRAb) or TSBAb levels were measured within a year from the initial visit were included. The median age at diagnosis was 9.3 years, and the estimated time between onset and diagnosis was 2.6 yr. The positive rate for either TSBAb or TRAb was 38.8% (95% confidence interval: 18.3–59.5%). There were no significant differences in age, the estimated time between onset and diagnosis, and FT4 levels at diagnosis between the TSBAb-positive and -negative groups. Unlike previous reports, we showed that the prevalence of TSBAb-positivity in childhood-onset AATs is not rare, as in adults.

This multicenter prospective cohort study followed up Japanese children who had just started GH therapy using a drug delivery device (GROWJECTOR® L) linked to a newly developed smartphone application and analyzed precise medication adherence data stored in GROWJECTOR® L to evaluate the usefulness of the application in improving GH therapy adherence over a 24-wk observation period. Moreover, a questionnaire survey on GH therapy and the smartphone application was conducted, and factors affecting adherence to GH therapy were assessed. This study enrolled 60 children with short stature who had GH deficiency or Turner syndrome or were small for gestational age from 28 Japanese medical institutions and analyzed 57 of them. The median and mean adherence rates after 24 wk of observation were 96% and 93%, respectively. Although adherence rates were significantly lower from wk 16 to wk 20 than from wk 1 to wk 4, cumulative adherence rates remained high throughout the observation period. The questionnaire analysis revealed that most patients actively used the application. Overall, our results suggest that active discussion regarding the development of healthcare systems that contribute toward improving the patient quality of life is warranted.

Mauriac syndrome is a rare and underdiagnosed complication of type 1 diabetes mellitus (T1DM). It is characterized by growth retardation, delayed puberty, Cushingoid features, hepatomegaly, and increased transaminase levels. The term glycogenic hepatopathy has been used to describe patients with poorly controlled T1DM and glycogen overload in the hepatocytes but without all the features of Mauriac syndrome. Although rare, glycogenic hepatopathy is reported to be the main cause of hepatomegaly in young patients with T1DM. We report two cases of glycogenic hepatopathy in children with poorly controlled T1DM. Both children had hepatomegaly, elevated liver enzyme levels, and elevated lactate levels. A liver biopsy confirmed the diagnosis of glycogenic hepatopathy in both patients. In conclusion, hepatomegaly with elevated liver enzymes, negative infective and metabolic screenings and persistently elevated plasma lactate levels should raise the suspicion of glycogenic hepatopathy in poorly controlled T1DM. Early diagnosis and improvement in glycemic control are the mainstays of treatment, which can prevent long-term complications.

Complete androgen insensitivity syndrome (CAIS) is caused by mutations in the androgen receptor gene. Patients with this syndrome have a 46,XY karyotype, male gonads, and normal female external genitalia. While the pre-pubertal risk of developing gonadal tumors is low in these patients, it increases with age. Most gonadal tumors arise from germ cells; stromal cell tumors are uncommon. Herein, we report a CAIS patient with a feminizing Sertoli cell tumor. The patient presented at 8 yr of age with breast enlargement and growth acceleration, concomitant with elevated serum estradiol levels and suppressed serum gonadotropin levels; these findings were inconsistent with CAIS. The patient underwent gonadectomy at 10 yr of age, and histology demonstrated presence of a non-malignant Sertoli cell tumor in the right gonad. We conclude that this is the first reported case of CAIS with accelerated onset of puberty resulting from a Sertoli cell tumor.

Vitamin D deficiency is a major cause of hypocalcemic seizures in infants. Chronic enteropathy can cause both malnutrition and vitamin deficiency disorders, such as celiac disease, in Western Caucasians. However, gluten-related disorders are considered uncommon in most Asian countries, and there have been no reports of any infant being diagnosed with a gluten-related disorder in Japan. Here, we describe a case where a Japanese infant, with non-celiac gluten sensitivity, presented with hypocalcemic seizures resulting from a vitamin D deficiency. In this case, an eight-month-old boy had an afebrile seizure, and blood tests revealed both hypocalcemia and prolonged prothrombin time resulting in his transfer to our hospital. The presence of fatty stools and evidence of multiple vitamin deficiencies indicated some form of fat malabsorption. His laboratory and histological findings showed enteropathy, and he was thus diagnosed with non-celiac gluten sensitivity. Therefore, he was treated with a gluten-free diet supplemented with vitamins. This case suggests that infants with a vitamin D deficiency caused by celiac disease or non-celiac gluten sensitivity should be carefully monitored when they are given oral supplements of vitamin D, to prevent any adverse side-effects associated with the varied roles of vitamin D in the immune response.