Carvalho Cunha Nelson, Gomes Leonor, Bastos Margarida
Serviço de Endocrinologia, Diabetes e Metabolismo, Centro Hospitalar e Universitario de Coimbra EPE, Coimbra, Portugal.
Faculdade de Medicina da Universidade de Coimbra, Coimbra, Portugal.
BMJ Case Rep. 2019 Jul 19;12(7):e229430. doi: 10.1136/bcr-2019-229430.
The elevation of thyroid hormone with a normal or elevated thyroid-stimulation hormone (TSH) occurs uncommonly. This set a diagnosis challenge between TSH-secreting pituitary adenoma and resistance to thyroid hormone (RTH). We report a case of a young female patient with palpitations, with elevated thyroid hormone and non-suppressed TSH. TSH receptor antibody was undetectable. Thyroid ultrasound revealed mild heterogeneous goitre, and MRI revealed a microadenoma with 7.5 mm length in pituitary's left lobe. Pituitary hormones were within normal ranges. The thyrotropin-releasing hormone stimulation test showed normal TSH elevation, consistent with RTH. The genetic test revealed a mutation in heterozygosity in THRB gene (G344R) confirming RTH-beta. No pituitary surgery or thyroidectomy was performed nor were prescribed any antithyroid drugs. Inappropriate secretion of TSH requires a high level of clinical suspicion and the proper laboratory, genetic and radiological studies to conduct a correct diagnosis and prevent unnecessary and potential harmful therapies.
甲状腺激素升高而甲状腺刺激激素（TSH）正常或升高的情况并不常见。这给促甲状腺激素分泌型垂体腺瘤和甲状腺激素抵抗（RTH）之间的诊断带来了挑战。我们报告一例年轻女性患者，有心悸症状，甲状腺激素升高且TSH未被抑制。未检测到TSH受体抗体。甲状腺超声显示轻度不均匀性甲状腺肿，MRI显示垂体左叶有一个长7.5毫米的微腺瘤。垂体激素在正常范围内。促甲状腺激素释放激素刺激试验显示TSH正常升高，符合RTH。基因检测显示THRB基因杂合突变（G344R），确诊为RTH-β。未进行垂体手术或甲状腺切除术，也未开任何抗甲状腺药物。TSH的不适当分泌需要高度的临床怀疑以及适当的实验室、基因和放射学研究，以做出正确诊断并防止不必要的和潜在有害的治疗。
