Case Report
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World J Diabetes. Oct 15, 2013; 4(5): 227-230
Published online Oct 15, 2013. doi: 10.4239/wjd.v4.i5.227
Sequential elevation of autoantibodies to thyroglobulin and glutamic acid decarboxylase in type 1 diabetes
Eiji Kawasaki, Jun-ichi Yasui, Masako Tsurumaru, Haruko Takashima, Toshiyuki Ikeoka, Fumi Mori, Satoru Akazawa, Ikuko Ueki, Masakazu Kobayashi, Hironaga Kuwahara, Norio Abiru, Hironori Yamasaki, Atsushi Kawakami
Eiji Kawasaki, Toshiyuki Ikeoka, Department of Metabolism/Diabetes and Clinical Nutrition, Nagasaki University Hospital, Nagasaki 852-8501, Japan
Jun-ichi Yasui, Haruko Takashima, Fumi Mori, Satoru Akazawa, Ikuko Ueki, Masakazu Kobayashi, Hironaga Kuwahara, Norio Abiru, Atsushi Kawakami, First Department of Internal Medicine, Nagasaki University Graduates School of Biomedical Sciences, Nagasaki 852-8501, Japan
Masako Tsurumaru, Clinical Research Center, Nagasaki University Hospital, Nagasaki 852-8501, Japan
Hironori Yamasaki, Center for Health and Community Medicine, Nagasaki University, Nagasaki 852-8521, Japan
Author contributions: Kawasaki E performed research and wrote the paper; Yasui J, Tsurumaru M, Takashima H, Ikeoka T, Mori F, Akazawa S, Ueki I, Kobayashi M, Kuwahara H, Abiru N, Yamasaki H and Kawakami A contributed to the discussion and reviewed the manuscript.
Correspondence to: Eiji Kawasaki, MD, PhD, Department of Metabolism/Diabetes and Clinical Nutrition, Nagasaki University Hospital, 1-7-1 Sakamoto, Nagasaki 852-8501, Japan. eijikawa@nagasaki-u.ac.jp
Telephone: +81-95-8197550 Fax: +81-95-8197552
Received: June 25, 2013
Revised: August 1, 2013
Accepted: August 16, 2013
Published online: October 15, 2013
Processing time: 112 Days and 14.7 Hours
Abstract

We have previously reported the high levels of glutamic acid decarboxylase 65 autoantibodies (GAD65A) in patients with type 1 diabetes and autoimmune thyroid disease. Here we describe a 32-year-old Japanese female with a thirteen-year history of type 1 diabetes whose levels of GAD65A were elevated just after the emergence of anti-thyroid autoimmunity. At 19 years of age, she developed diabetic ketoacidosis and was diagnosed with type 1 diabetes. She had GAD65A, insulinoma-associated antigen-2 autoantibodies (IA-2A), and zinc transporter-8 autoantibodies (ZnT8A), but was negative for antibodies to thyroid peroxidase (TPOAb) and thyroglobulin (TGAb) at disease onset. ZnT8A and IA-2A turned negative 2-3 years after the onset, whereas GAD65A were persistently positive at lower level (approximately 40 U/mL). However, just after the emergence of TGAb at disease duration of 12.5 years, GAD65A levels were reelevated up to 5717 U/mL in the absence of ZnT8A and IA-2A. Her thyroid function was normal and TPOAb were consistently negative. She has a HLA-DRB1*03:01/*04:01-DQB1*02:01/*03:02 genotype. Persistent positivity for GAD65A might be associated with increased risk to develop anti-thyroid autoimmunity.

Keywords: Autoimmune thyroid disease, Case report, Glutamic acid decarboxylase autoantibodies, Type 1 diabetes

Core tip: This paper describes a case of type 1 diabetes whose levels of glutamic acid decarboxylase 65 autoantibodies (GAD65A) were reelevated just after the emergence of anti-thyroid autoimmunity at disease duration of 12.5 years without any clinical signs of thyroid dysfunction. This case report suggests that persistent positivity for GAD65A is associated with increased risk to develop anti-thyroid autoimmunity.