Graves' Disease with Thymic Hyperplasia: The Response of the Thyroid Function, Thyrotropin Receptor Autoantibody, and Thymic Size to Thiamazole Treatment

• Published in: Internal Medicine Vol. 61; no. 18; pp. 2753 - 2757
• Main Authors: Tsukada, Daichi, Iizuka, Katsumi, Takao, Ken, Liu, Yanyan, Kubota, Sodai, Okamoto-Kubota, Saki, Sakurai, Teruaki, Imaizumi, Toshinori, Sakai, Mayu, Kato, Takehiro, Mizuno, Masami, Hirota, Takuo, Suwa, Tetsuya, Horikawa, Yukio, Yamamoto, Mayumi, Kubota, Sumihisa, Yabe, Daisuke
• Format: Journal Article
• Language: English
• Published: Tokyo The Japanese Society of Internal Medicine 15-09-2022; Japan Science and Technology Agency
• Subjects: Autoantibodies; Autoimmunity; Case Report; Graves' disease; Hyperplasia; Internal medicine; Magnetic resonance imaging; sIL-2R; soluble interleukin-2 receptor; thymic hyperplasia; Thymus; Thyroid; Thyroid-stimulating hormone; Thyrotoxicosis
• ISSN: 0918-2918; 1349-7235
• DOI: 10.2169/internalmedicine.8710-21

We treated a 22-year-old woman suffering from Graves' disease and thymic hyperplasia. She was referred to our institution for a close investigation of thyrotoxicosis and thymic mass. Thyroid tests and magnetic resonance imaging resulted in a diagnosis of Graves' disease and thymic hyperplasia. The thyroid function and thyroid-stimulating hormone receptor antibody (TRAb) were normalized one and five months after thiamazole initiation, respectively. The thymic size began to decrease after 1 month and was further decreased after 5 months; it was normalized after 12 months. The correlation between TRAb titers and the thymic size (R2=0.99) suggested that the patient's autoimmunity might have contributed to the thymic hyperplasia.