Complicated foregut duplication cyst presenting as broncho-oesophageal fistula

Oesophageal duplication cysts are a subtype of foregut cysts, associated with the presence of ectopic gastric mucosa. Gastric acid secreted by this mucosa can lead to complications. We report one such unusual case of complication leading to the formation of broncho-oesophageal fistula in a duplication cyst. A girl in her middle childhood presented with a long-duration cough and multiple respiratory infections. On investigation, a right-sided paraoesophageal air-filled cystic lesion was identified, with a possible communication with the airway, confirmed by an oral contrast study. On further workup, a positive uptake was noted on Meckel's scan, signifying the presence of ectopic gastric mucosa. The findings were confirmed surgically and on histopathology and were consistent with a duplication cyst with broncho-oesophageal fistula. An unexplained upper respiratory tract symptomatology should mandate imaging, which would enable early detection and appropriate surgical management of such cysts in infancy and childhood.