1

Introduction

Fourth branchial cleft anomalies are very rare, accounting for less than 1% of all branchial anomalies. They typically arise as a tract from the hypopharynx and usually present as a lower neck abscess. Based on embryologic analysis, it has been theorized that a complete fourth branchial fistula would extend inferiorly into the mediastinum before rising back into the neck . No reports have previously described a tract extending into the chest. We present a case of a male infant presenting with respiratory distress and pneumomediastinum that resulted from a fourth branchial cleft anomaly.

2

Case report

A 4-month-old white male infant presented to the emergency department with respiratory distress. Additional history obtained included decreased oral intake and urine output over several days before presentation. Further questioning revealed the patient had significant regurgitation of feedings for at least 2 months. History of trauma or caustic ingestion was denied by both parents. There was no history of intubation or nasogastric tube placement. The patient’s medical history was notable for failure to thrive based on his weight being less than fifth percentile for his age.

Physical examination was notable for a fever of 102°F and weight less than the 5th percentile for age. Respirations were mildly labored, and the patient exhibited some retractions. There was obvious anterior neck swelling without palpable crepitus. Auscultation of the chest revealed bilateral rales. White blood cell count was 25 200 (21% bands, 61% segs). The patient required blow-by oxygen to maintain his saturation to more than 90%. A chest radiograph was obtained, which was consistent with pneumomediastinum. A skeletal series showed no evidence of bony trauma.

The patient was admitted to the pediatric critical care unit and stabilized with appropriate intravenous fluids and antibiotics. A nasogastric tube was placed (the patient’s neck swelling and radiographic changes were present before tube placement). During this period, neck and chest computed tomographic scans ( Fig. 1 ) were obtained that showed multiple air-fluid levels in the retropharyngeal space extending inferiorly into the mediastinum to the level of the aortic arch. An esophagram ( Fig. 2 ) displayed extrusion of contrast from the hypopharynx.

Axial computed tomography just above level of carina.

Lateral view of esophagram.

After review of the neck and chest computed tomographic scans as well as the esophagram, an otolaryngologist and pediatric surgeon were consulted. The pediatric surgeon felt that open drainage of the mediastinal fluid collection was not indicated. The patient was taken to the operating room urgently by the otolaryngologist for direct visualization of the hypopharynx. In the right piriform apex, a 5-mm opening was seen in the mucosa with a lined tract extending inferiorly into the mediastinum ( Figs. 3 and 4 ). The sinus opening was then cauterized extensively with silver nitrate.

Sinus tract opening in the right piriform apex.

Sinus tract opening (bottom) with nasogastric tube passing into esophagus (top left).

Postoperatively, the patient remained NPO with nasogastric tube feedings. Fifteen days later, repeat endoscopy was performed that showed complete closure of the sinus tract with a small amount of granulation tissue, which was again cauterized. Closure of the tract was confirmed 11 days later with a repeat esophagram as well as a third endoscopy, after which the patient was restarted on oral feeds without any problems. After more than 1 year of follow-up, he continues to gain weight and develop appropriately.