Extensive Esophageal Duplication in New Zealand Adult Male Demonstrated on Endoscopy and Barium Swallow With Valsalva Maneuver

This case report details the diagnosis of an extensive tubular esophageal duplication in a New Zealand adult patient. A 48‐year‐old man presented to a regional hospital with fever and respiratory symptoms; initial noncontrast CT imaging suggested the impression of a fluid‐filled structure possibly representing a hiatal hernia. However, subsequent upper gastrointestinal endoscopy (OGD) revealed an unexpected second lumen in the fundus. The mucosa lining this secondary lumen notably appeared similar to small bowel mucosa, suggesting possible esophageal duplication opening distally at the gastroesophageal junction, representing a rare congenital anomaly. This endoscopic observation prompted targeted advanced imaging based on radiology multidisciplinary meeting (MDM) discussion. Barium swallow with dynamic Valsalva maneuver definitively confirmed the diagnosis, demonstrating reflux contrast illumination into an extensive tubular esophageal duplication, supported by cross‐sectional imaging. The manuscript is accompanied by two high‐quality figures, showing the condition demonstrated by color upper GI endoscopic images and key selected frames from a barium swallow esophagram and computed tomography of the chest, abdomen, and pelvis (CTCAP). This case highlights the essential role of endoscopy in identifying key internal anatomic features which, when combined with dynamic imaging, are vital for diagnosing rare congenital entities in patients presenting with nonspecific adult symptoms.