每日一题_2023.05.22

A physician is asked to evaluate a 5-year-old girl who has developed a mass in her neck. During the interview, he learns that the mass appeared within the past few months and has been enlarging; however, it causes no pain or discomfort. The mass is in the midline of the neck just inferior to the hyoid bone. Laboratory tests reveal a triiodothyronine level of 150 ng/dL, a thyroxine level of 8.0 μg/dL, and a thyroid-stimulating hormone level of 1 μU/ mL. A CT scan of the neck is performed and the doctor recommends surgery. Which of the following is the most likely diagnosis?

一名医生被要求评估一名颈部有肿块的5岁女孩。在采访中，他了解到，肿块是近几个月出现的，并且一直在扩大;然而，它不会引起疼痛或不适。肿块位于颈部中线，就在舌骨下方。实验室检查显示三碘甲状腺原氨酸水平为150 ng/dL，甲状腺素水平为8.0 μg/dL，促甲状腺激素水平为1 μU/ mL，进行了颈部CT扫描，医生建议手术。下列哪一项是最可能的诊断?

(A) Branchial cleft cyst鳃裂囊肿

(B) Dermoid cyst皮样囊肿

(C) Ectopic thyroid gland异位甲状腺

(D) Enlarged pyramidal lobe of the thyroid 甲状腺锥体叶增大

(E) Lipoma 脂肪瘤

(F) Thyroglossal duct cyst甲状舌管囊肿

答案解析：

甲状腺起源于咽底的甲状腺憩室。在发育过程中向下进入颈部，但仍然通过甲状舌管与舌头相连。甲状舌管最终消失，在舌根处留下一个小腔(盲肠孔)。甲状腺的锥体叶可以被认为是导管的尾部。偶尔，部分导管上皮存在颈部并可能形成囊肿。甲状舌管囊肿通常无疼痛或轻微压痛，出现在颈部中线。它们通常出现在舌骨上方或下方，但也可能出现在舌根和甲状腺之间的任何地方。如果甲状腺正常，建议手术切除甲状舌管囊肿以预防感染。在此例中，正常的三碘甲状腺原氨酸、甲状腺素和促甲状腺激素(TSH)水平表明甲状腺正常，并通过CT扫描证实。

正确答案：E