論文種別 症例報告
言語種別 英語
査読の有無 その他(不明)
表題 Adrenal insufficiency influences the pattern of thyrotoxicosis toward triiodothyronine predominance.
掲載誌名 正式名:JCEM case reports
略  称:JCEM Case Rep
ISSNコード:27551520/27551520
掲載区分国外
巻・号・頁 4(7),pp.luag149
著者・共著者 Azusa Maruoka, Kumiko Nishimura, Chika Mukai, Kazuhisa Takahashi, Junichiro Irie, Nagaoki Toyoda
発行年月 2026/06
概要 Serum-free thyroxine (FT4) levels are typically higher than free triiodothyronine (FT3) levels at the onset of thyrotoxicosis in patients with painless thyroiditis, reflecting the high ratio of stored thyroid hormone in the thyroid gland. We report a case of a 58-year-old man with painless thyroiditis and adrenal insufficiency caused by isolated adrenocorticotropin (ACTH) deficiency (IAD). Upon admission, the FT3 level was high, while the FT4 level was within the normal range. Likewise, the FT3/FT4 ratio was high. Therefore, the diagnosis of triiodothyronine (T3) thyrotoxicosis was made. He was diagnosed with painless thyroiditis because he did not have neck pain, and 99mTechnetium-thyroid scintigraphy revealed low thyroid uptake. The FT3/FT4 ratio fell after the increased serum cortisol level via daily administration of tetracosactide acetate. The elevated FT3/FT4 ratio in this patient could be explained by increased T4 to T3 conversion in a low-cortisol state. It has been suggested that destructive thyroiditis, accompanied by a high FT3/FT4 ratio, is a valuable indicator of the accompaniment of adrenal deficiency.
DOI 10.1210/jcemcr/luag149
PMID 42245472