[Pediatric Thyroiditis Secondary to Fourth Branchial Arch Anomaly: A Case Series]

A fourth branchial cleft remnant is relatively rare and often misdiagnosed, primarily presenting as a sinus with an opening in the pyriform sinus, known as pyriform sinus fistula. Confirmation of the diagnosis is achieved through either a barium swallow test, or direct rigid laryngoscopy. We present our experience in diagnosing this anomaly.

The series comprised 6 children, 4 boys and 2 girls 1-13 years of age, all with left cervical infection. Five patients presented with a primary episode of cervical infection, while in one case, it was a second infection. Diagnosis was confirmed in all cases by direct visualization of the tract opening in the left pyriform sinus. Treatment involved endoscopic cauterization of the fistula by diathermy for all patients. One child experienced a recurrent infection post-diathermic treatment and had a second successful cauterization.

We retrospectively reviewed six children referred to our medical center between the years 2020 and 2023, due to cervical infection who had a final diagnosis of fourth branchial cleft sinus.

A fourth branchial arch anomaly is a relatively rare diagnosis that may mimic thyroiditis. Diagnosing this anomaly can be challenging and requires direct visualization of the fistulae in the pyriform sinus. Familiarity with this diagnosis is essential for enabling efficient and prompt diagnosis and treatment.