Eosinophilic esophagitis (e-o-sin-o-FILL-ik uh-sof-uh-JIE-tis) is a chronic immune system disease in which a type of white blood cell (eosinophil) builds up in the lining of the tube that connects your mouth to your stomach (esophagus). This buildup, which is a reaction to foods, allergens or acid reflux, can inflame or injure the esophageal tissue. Damaged esophageal tissue can lead to difficulty swallowing or cause food to get stuck when you swallow.
Eosinophilic esophagitis has been identified only since the early 90s, but is now considered a major cause of digestive system (gastrointestinal) illness. Research is ongoing and will likely lead to revisions in the diagnosis and treatment of eosinophilic esophagitis.