With the advances in technology and medical knowledge, new diseases are being identified and investigated. Esophageal motility disorders have been re-defined using high-resolution manometry and their pathogenesis are being better understood. The use of opioid analgesics is increasing worldwide, particularly in the United States, but their chronic use can cause opioid-induced esophageal dysfunction, which mimics spastic motor disorders, including achalasia type 3 or 2 and esophagogastric junction outflow obstruction. Eosinophilic esophagitis is identified by eosinophilic infiltration confirmed on a pathological examination. The condition is often associated with esophageal motility abnormalities. On the other hand, recent studies have suggested that muscle-predominant eosinophilic infiltration, eosinophilic esophageal myositis, might manifest as spastic motor disorders, including achalasia or jackhammer esophagus. Lymphocytic esophagitis is an unusual esophageal condition, which is confirmed by the increased number of lymphocytes in the esophageal epithelium. Although several reports have supported the existence of lymphocytic esophagitis, it is still unclear whether lymphocytic esophagitis is a distinct disease entity or another spectrum of other esophageal diseases, such as gastroesophageal reflux disease or eosinophilic esophagitis. This review presents evidence and reports on the emerging issues in esophageal motility disorders, including opioid-induced esophageal dysfunction, eosinophilic esophagitis with eosinophilic esophageal myositis, and lymphocytic esophagitis.
Keywords: Eosinophilic esophageal myositis; Eosinophilic esophagitis; Esophageal dysfunction; Lymphocytic esophagitis; Opioid-induced esophageal dysfunction.