Review article: gastric emptying in functional gastrointestinal disorders.

Although delayed gastric emptying has been described in several functional gastrointestinal disorders, and appears to be especially common in functional dyspepsia, the relationship of this finding to symptoms and basic pathophysiology is difficult to define. The delineation of the interactions between delayed gastric emptying, on the one hand, and symptom pathogenesis, on the other, has been hampered by several factors. These include the limitations of the methodology itself, the extent of overlap between the various functional disorders and the sensitivity of gastric emptying to factors external to the stomach, be they elsewhere within the gastrointestinal tract, in the central nervous system or in the environment. In many instances, delayed gastric emptying is an epiphenomenon, reflecting the overlap between inadequately defined functional syndromes, shared pathophysiology or the activation of physiological interactions between the various organs of the gut. In others, it may imply a truly diffuse motor disorder. The disappointments attendant on attempts to alleviate symptoms through approaches designed to accelerate gastric emptying should therefore not come as a surprise. Pending the definition of the true significance of delayed gastric emptying in all functional gastrointestinal disorders, caution should be exerted in the interpretation of this finding in a patient with functional symptoms.