A 12-year-old boy is brought to the office due to a left neck mass. One month ago, he had a fever and upper respiratory tract infection symptoms. A week later, he noticed a painful lump in the left side of his neck. He also has leakage of fluid from a hole below the mass. On examination, there is a cystic left neck mass and a small pit anterior to the sternocleidomastoid muscle that is leaking mucopurulent fluid. Which of the following is the most likely diagnosis of this lesion?

Question

A 12-year-old boy is brought to the office due to a left neck mass.  One month ago, he had a fever and upper respiratory tract infection symptoms.  A week later, he noticed a painful lump in the left side of his neck.  He also has leakage of fluid from a hole below the mass.  On examination, there is a cystic left neck mass and a small pit anterior to the sternocleidomastoid muscle that is leaking mucopurulent fluid.  Which of the following is the most likely diagnosis of this lesion?

Quizplus · Accepted Answer

11ec25c8_d650_5bb9_bc81_57738fcc23e3_MD0003_00 This child with a lateral, cystic neck mass has a branchial cleft cyst (BCC). The branchial apparatus is an embryologic structure, composed of paired arches separated by clefts, which forms many face and neck structures. Abnormalities in the embryologic development of these structures can lead to cysts, sinuses, fistulae, and/or cartilaginous remnants along the paths of development. branchial cleft cyst cysts Abnormalities most often arise from the second branchial arch, which forms structures in the face and upper neck. Therefore, BCCs are most often located between the internal and external carotid arteries, anterior to the sternocleidomastoid muscle and inferior to the mandible. Surgical resection of the entire cyst and any associated fibrous tract remnants is curative. Similar to a thyroglossal duct cyst (TDC), which is also formed from incomplete involution of an embryologic remnant, a BCC is often detected when it becomes secondarily infected after an upper respiratory tract infection (URI), leading to erythema, tenderness, and sometimes drainage of fluid from a sinus tract. However, a TDC is located in the midline because the path of thyroid descent is from the base of tongue to its location in the midline lower neck (Choice E). thyroglossal duct cyst secondarily infected (Choice A) Actinomyces lymphadenitis can present as a submandibular mass with a draining sinus tract. However, it typically occurs after dental infections or trauma in immunosuppressed patients and the sinus tracts drain sulfur granules. (Choice C) A cystic hygroma is formed from dilated lymphatic vessels and presents as a lateral, cystic neck mass. However, it occurs most commonly in the posterior triangle of the neck and is typically diagnosed at birth or on prenatal ultrasound. cystic hygroma (Choice D) A laryngocele is an outpouching of the laryngeal mucosa that can be congenital or acquired. If it protrudes through the thyrohyoid membrane, it can present as a lateral neck mass. It characteristically enlarges with Valsalva maneuver due to inflation with air. Acquired laryngoceles are classically seen in glassblowers or trumpet players due to repeated, intense oropharyngeal pressure. Educational objective: A branchial cleft cyst is a congenital neck mass that often presents in later childhood after an upper respiratory tract infection. It is typically located inferior to the mandible and anterior to the sternocleidomastoid muscle. References: Correlation between pre-operative diagnosis and post-operative pathology reading in pediatric neck masses-a review of 281 cases. (http://www.ncbi.nlm.nih.gov/pubmed/25479698)

A 12-Year-Old Boy Is Brought to the Office Due to a Left