Eosinophilic esophagitis is a rare allergic condition that is difficult to diagnose. The condition is known for inflammation and the growth of many white blood cells in the esophagus. The Pathology team performs a biopsy of the esophagus to study the cells of the esophageal wall. If eosinophilic esophagitis is detected, more tests will be performed to figure out allergic triggers and causes.