Department of Diabetes, Endocrinology and Metabolism, Kawasaki Medical School, Japan.
Department of Diabetic Medicine, Kurashiki Central Hospital, Japan.
Medicine (Baltimore). 2021 Dec 30;100(52):e28414. doi: 10.1097/MD.0000000000028414.
Syndrome of inappropriate secretion of thyroid-stimulating hormone (SITSH) is a rare cause of hyperthyroidism. Thyroid-stimulating hormone (TSH) levels are usually normal or high, and triiodothyronine (FT3) and free thyroxine (FT4) levels are usually high in subjects with SITSH.
A 37-year-old woman had experienced galactorrhea and menstrual disorder for a couple of years before. She had undergone infertility treatment in 1 year before, hyperthyroidism was detected and she was referred to our institution.
She was suspected of having SITSH and was hospitalized at our institution for further examination. The data on admission were as follows: FT3, 4.62 pg/mL; FT4, 1.86 ng/dL; TSH, 2.55 μIU/mL. Although both FT3 and FT4 levels were high, TSH levels were not suppressed, which is compatible with SITSH. In addition, in brain contrast-enhanced magnetic resonance imaging, nodular lesions were observed in the pituitary gland with a diameter of approximately 10 mm. In the thyrotropin-releasing hormone load test, TSH did not increase at all, which was also compatible with TSH-secreting pituitary adenoma. In the octreotide load test, the TSH levels were suppressed. Based on these findings, we diagnosed this subject as SITSH.
Hardy surgery was performed after the final diagnosis. In TSH staining of the resected pituitary adenoma, many TSH-producing cells were observed. These findings further confirmed the diagnosis of pituitary adenoma producing TSH.
Approximately 2 months after the operation, TSH, FT3, and FT4 levels were normalized. Approximately 3 months after the operation, she became pregnant without any difficulty.
We should consider the possibility of SITSH in subjects with galactorrhea, menstrual disorders, or infertility. In addition, we should recognize that it is very important to repeatedly examine thyroid function in subjects with galactorrhea, menstrual disorder, or infertility.
促甲状腺激素（TSH）不适当分泌综合征（SITSH）是一种罕见的甲状腺功能亢进症病因。患有 SITSH 的患者的 TSH 水平通常正常或升高，三碘甲状腺原氨酸（FT3）和游离甲状腺素（FT4）水平通常升高。
一位 37 岁女性，数年前曾出现溢乳和月经紊乱，1 年前因不孕接受治疗时发现患有甲状腺功能亢进症，后转至我院就诊。
考虑为 SITSH，收住我院进一步检查。入院时的检查数据如下：FT3，4.62pg/mL；FT4，1.86ng/dL；TSH，2.55μIU/mL。尽管 FT3 和 FT4 水平均升高，但 TSH 并未受到抑制，符合 SITSH 表现。此外，垂体对比增强磁共振成像显示垂体有直径约 10mm 的结节性病变。促甲状腺激素释放激素负荷试验中，TSH 无任何增加，也符合促甲状腺激素分泌垂体腺瘤的表现。奥曲肽负荷试验中，TSH 水平受到抑制。基于这些发现，诊断该患者为 SITSH。
最终确诊后进行了 Hardy 手术。切除的垂体腺瘤 TSH 染色中观察到许多 TSH 分泌细胞，进一步证实了垂体腺瘤分泌 TSH 的诊断。
术后约 2 个月，TSH、FT3 和 FT4 水平恢复正常。术后约 3 个月，她顺利怀孕。
对于有溢乳、月经紊乱或不孕的患者，应考虑 SITSH 的可能性。此外，对于有溢乳、月经紊乱或不孕的患者，应认识到反复检查甲状腺功能非常重要。
