What histological findings are associated with eosinophilic esophagitis?

Eosinophilic esophagitis is characterized histologically by the significant infiltration of eosinophils within the esophageal epithelium. The presence of sheets or clusters of eosinophils is a hallmark finding and indicates an allergic or inflammatory response. Along with this eosinophilic infiltration, patients often exhibit linear furrows due to chronic inflammation and remodeling of the esophageal tissue. These histopathological features are pivotal for diagnosing eosinophilic esophagitis, as they reflect the underlying pathophysiological process whereby allergen exposure leads to immune-mediated esophageal inflammation.

The presence of lymphocytes in the mucosa may also be observed, but it is not the defining feature for eosinophilic esophagitis—lymphocytes are more commonly associated with other conditions. The formation of cysts within the epithelium is not a noted finding for eosinophilic esophagitis and suggests a different pathological process. Similarly, the presence of neutrophils and ulcers is indicative of acute inflammatory conditions, such as infections or reflux esophagitis, and does not typically occur in eosinophilic esophagitis. The prominent eosinophilic infiltration, along with associated structural changes like