Neck masses are a common finding in the pediatric population, with a broad differential diagnosis resulting in real diagnostic challenges. They are most frequently caused by reactive lymphadenopathy, infectious lymphadenitis, or congenital anomalies of the neck. This case report describes a 16-year-old female presenting to the pediatric emergency department with 5 weeks of right-sided neck mass. Based on her history, physical examination, and prolonged clinical course, the differential diagnosis included infectious, congenital, and neoplastic causes. The patient was ultimately diagnosed with a branchial cleft cyst and referred to a pediatric head and neck surgeon.

中文翻译：

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青春期女性的慢性侧颈部肿块

颈部肿块是儿科人群中的常见发现，广泛的鉴别诊断导致真正的诊断挑战。它们最常由反应性淋巴结病、传染性淋巴结炎或颈部先天性异常引起。本病例报告描述了一名 16 岁女性因右侧颈部肿块 5 周就诊于儿科急诊科。根据病史、体格检查和延长的临床病程，鉴别诊断包括感染性、先天性和肿瘤性病因。该患者最终被诊断出患有鳃裂囊肿，并转诊给儿科头颈外科医生。