著者

Keisuke Nagasaki Akie Nakamura Takeru Yamauchi Hotaka Kamasaki Yosuke Hara Junko Kanno Satomi Koyama Yoshiaki Ohtsu Ikuko Takahashi Shigeru Suzuki Kenichi Kashimada Toshihiro Tajima

出版者

The Japanese Society for Pediatric Endocrinology

雑誌

Clinical Pediatric Endocrinology (ISSN:09185739)

巻号頁・発行日

vol.30, no.2, pp.79-84, 2021 (Released:2021-04-03)

参考文献数

16

被引用文献数

2

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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.

著者

Yujiro Nakano Chikara Komiya Hitomi Shimizu Hiroyuki Mishima Kumiko Shiba Kazutaka Tsujimoto Kenji Ikeda Kenichi Kashimada Sumito Dateki Koh-ichiro Yoshiura Yoshihiro Ogawa Tetsuya Yamada

出版者

The Japan Endocrine Society

雑誌

Endocrine Journal (ISSN:09188959)

巻号頁・発行日

vol.67, no.11, pp.1099-1105, 2020 (Released:2020-11-28)

参考文献数

27

被引用文献数

3 3

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Sitosterolemia is caused by homozygous or compound heterozygous gene mutations in either ATP-binding cassette subfamily G member 5 (ABCG5) or 8 (ABCG8). Since ABCG5 and ABCG8 play pivotal roles in the excretion of neutral sterols into feces and bile, patients with sitosterolemia present elevated levels of serum plant sterols and in some cases also hypercholesterolemia. A 48-year-old woman was referred to our hospital for hypercholesterolemia. She had been misdiagnosed with familial hypercholesterolemia at the age of 20 and her serum low-density lipoprotein cholesterol (LDL-C) levels had remained about 200–300 mg/dL at the former clinic. Although the treatment of hydroxymethylglutaryl-CoA (HMG-CoA) reductase inhibitors was ineffective, her serum LDL-C levels were normalized by ezetimibe, a cholesterol transporter inhibitor. We noticed that her serum sitosterol and campesterol levels were relatively high. Targeted analysis sequencing identified a novel heterozygous ABCG5 variant (c.203A>T; p.Ile68Asn) in the patient, whereas no mutations were found in low-density lipoprotein receptor (LDLR), proprotein convertase subtilisin/kexin type 9 (PCSK9), or Niemann-Pick C1-like intracellular cholesterol transporter 1 (NPC1L1). While sitosterolemia is a rare disease, a recent study has reported that the incidence of loss-of-function mutation in the ABCG5 or ABCG8 gene is higher than we thought at 1 in 220 individuals. The present case suggests that serum plant sterol levels should be examined and ezetimibe treatment should be considered in patients with hypercholesterolemia who are resistant to HMG-CoA reductase inhibitors.