Functional esophageal disorders.
Functional esophageal disorders represent processes accompanied by typical esophageal symptoms (heartburn, chest pain, dysphagia, globus) that are not explained by structural disorders, histopathology-based motor disturbances, or gastroesophageal reflux disease. Gastroesophageal reflux disease is the preferred diagnosis when reflux esophagitis or excessive esophageal acid exposure is present or when symptoms are closely related to acid reflux events or respond to antireflux therapy. A singular, well-defined pathogenetic mechanism is unavailable for any of these disorders; combinations of sensory and motor abnormalities involving both central and peripheral neural dysfunction have been invoked for some. Treatments remain empirical, although the efficacy of several interventions has been established in the case of functional chest pain. Management approaches that modulate central symptom perception or amplification often are required once local provoking factors (eg, noxious esophageal stimuli) have been eliminated. Future research directions include further determination of fundamental mechanisms responsible for symptoms, development of novel management strategies, and definition of the most cost-effective diagnostic and treatment approaches.